WO2025213951A1 - Battery cell, battery, energy storage device, and electric device - Google Patents

Abstract

A battery cell, a battery, an energy storage device, and an electric device. The battery cell comprises a casing, an electrode assembly, a first electrode terminal, and a first insulating part. The casing has a first wall. The electrode assembly is arranged in the casing. The first electrode terminal is arranged on the first wall and is electrically connected to the electrode assembly, and the first electrode terminal is used for inputting and outputting electric energy. The first insulating part is arranged between the first wall and the first electrode terminal and is used for insulating and isolating the first electrode terminal from the first wall. The battery cell can effectively improve the reliability of the battery.

Description

Battery cells, batteries, energy storage devices and electrical devices

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese patent application No. 202410417335.7 filed on April 8, 2024, entitled “Battery Cell, Battery, Energy Storage Device and Electrical Device,” and the entire contents of the above application are incorporated herein by reference.

Technical Field

The present application relates to the field of battery technology, and in particular to a battery cell, a battery, an energy storage device, and an electrical device.

Background Art

Energy conservation and emission reduction are key to the sustainable development of the automotive industry. Electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of the sustainable development of the automotive industry. For electric vehicles, battery technology is a key factor in their development.

In the development of battery technology, how to improve battery reliability is a technical problem that needs to be solved urgently.

Summary of the Invention

The present application provides a battery cell, a battery, an energy storage device and an electrical device. The technical solution provided in the present application can effectively improve the reliability of the battery.

In a first aspect, the present application provides a battery cell. The battery cell includes a housing, an electrode assembly, a first electrode terminal, and a first insulating portion. The housing has a first wall. The electrode assembly is disposed within the housing. The first electrode terminal is disposed on the first wall and electrically connected to the electrode assembly, and is used for inputting and outputting electrical energy. The first insulating portion is disposed between the first wall and the first electrode terminal to insulate and isolate the first electrode terminal from the first wall.

In the above solution, by providing the first insulating portion between the first wall and the first electrode terminal, the first wall and the first electrode terminal can be effectively insulated and isolated, reducing the risk of internal short circuits in the battery cells due to a short circuit between the first wall and the first electrode terminal, thereby enhancing battery reliability. In particular, in energy storage devices operating at higher voltages, providing the first insulating portion between the first wall and the first electrode terminal can effectively reduce the risk of thermal runaway of the energy storage device due to the remaining battery cells in the battery running out of control, causing the outer casing to be charged with high voltage, resulting in the high voltage electricity flowing through the first wall and the electrode terminal, causing an internal short circuit in the battery cells.

According to some embodiments of the present application, the battery cell further includes a first deformable member electrically connected to the first wall, and the first deformable member is configured to be deformable to contact the first electrode terminal to electrically connect the first electrode terminal to the first wall.

In the above scheme, by providing a first deformable member, when the internal pressure of the battery cell reaches a certain level, for example, a first threshold value, the first deformable member can be deformed to contact the first electrode terminal, thereby electrically connecting the first electrode terminal to the first wall, thereby realizing an internal short circuit in the battery cell, so that the electrical connection components inside the battery cell are melted due to the large current generated by the short circuit, thereby cutting off the charge and discharge circuit of the battery cell, thereby playing a role in overcharge protection, and playing a role in reducing the risk of thermal runaway of the battery cell, thereby making the battery have higher reliability.

According to some embodiments of the present application, the first wall is formed with a first through hole and a second through hole, the first electrode terminal passes through the first through hole, the first deformable member closes the second through hole, and the first deformable member is configured to be deformable to partially pass through the second through hole to contact the first electrode terminal.

In the above scheme, when the internal pressure of the battery cell reaches a certain level, such as the first threshold value, the internal pressure of the battery cell can act on the first deformable member, so that the first deformable member deforms toward the outside of the first wall to effectively contact the first part of the first electrode terminal, thereby effectively realizing an internal short circuit of the battery cell, so that the electrical connection components inside the battery cell are melted due to the large current generated by the short circuit, so as to cut off the charge and discharge circuit of the battery cell, thereby reducing the risk of thermal runaway of the battery cell, and thus making the battery have higher reliability.

According to some embodiments of the present application, along the thickness direction of the first wall, a projection of a first portion of the first electrode terminal located outside the first wall at least partially overlaps with a projection of the first deformable member.

In the above scheme, by arranging the first deformable member corresponding to the first part along the thickness direction of the first wall, it is possible to quickly contact the first part with a smaller deformation amount when the internal pressure of the battery cell reaches a certain level, such as the first threshold value, so that the first electrode terminal and the first wall are quickly electrically connected, thereby effectively realizing an internal short circuit of the battery cell, so that the electrical connection components inside the battery cell are melted due to the large current generated by the short circuit, thereby cutting off the charge and discharge circuit of the battery cell, thereby reducing the risk of thermal runaway of the battery cell, and thus making the battery have higher reliability.

According to some embodiments of the present application, the first wall includes a main body portion and a first reinforcement portion connected to each other, and the first portion is provided on the first reinforcement portion.

In the above scheme, by providing the first reinforcement portion, the overall strength of the first wall can be improved, and the risk of deformation of the first wall due to internal pressure of the battery cell or external impact, which causes the first deformable member to be unable to effectively contact the first part to conduct electricity between the first electrode terminal and the first wall, can be reduced. The first deformable member can effectively contact the first electrode terminal under abuse conditions such as overcharging of the battery cell, thereby effectively playing the role of overcharging protection, reducing the risk of thermal runaway of the battery cell, and making the battery have higher reliability.

According to some embodiments of the present application, the length of the first wall is greater than or equal to 150 mm, and the width of the first wall is greater than or equal to 45 mm.

According to some embodiments of the present application, the first reinforcement portion includes a first protrusion, which protrudes from a surface of the main body portion along the thickness direction of the first wall.

In the above solution, by providing a first protrusion to strengthen the structural strength of the first wall, the risk of deformation of the first wall due to internal pressure of the battery cell or external impact, which causes the first deformable member to be unable to effectively contact the first part to conduct electricity between the first electrode terminal and the first wall, can be effectively reduced, thereby making the battery more reliable.

According to some embodiments of the present application, the first reinforcement portion further includes a first recessed portion, which is arranged on another surface of the main body portion along the thickness direction of the first wall, and the first recessed portion is arranged opposite to the first protruding portion.

In the above scheme, the first recess is provided at a position corresponding to the first protrusion. On the one hand, the difficulty of forming the first protrusion can be reduced and material costs can be saved. On the other hand, if the first recess is on the inner side of the first wall, the space of the first recess can be used to accommodate more active substances or electrolytes, which is beneficial to the improvement of the energy density or charge and discharge performance of the battery cell. If the first recess is on the outer side of the first wall, the space of the first recess can be used to accommodate external structural parts, which is beneficial to the improvement of the battery volume energy density.

According to some embodiments of the present application, the first protrusion is located on the outside of the first wall, and a first positioning groove is formed on the first protrusion. The first positioning groove accommodates the first part to limit the movement of the first part.

In the above scheme, by setting the first positioning groove, the first electrode terminal can be effectively positioned and the displacement of the first electrode terminal can be limited. On the one hand, the risk of the first electrode terminal being separated from the internal electrical connection component of the battery cell and causing internal short circuit of the battery cell is reduced. On the other hand, the first electrode terminal can be effectively cooperated with the first deformable member to play the role of overcharge protection and improve the reliability of the battery.

According to some embodiments of the present application, the first protrusion is located on the outside of the first wall, and along the thickness direction of the first wall, the dimension of the first protrusion protruding from the main body is greater than or equal to 0.1 mm and less than or equal to 5 mm.

In the above solution, by setting the protrusion of the first protrusion from the main body to be greater than or equal to 0.1mm, the structural strength of the first wall can be effectively improved, allowing the first deformable member to effectively contact the first electrode terminal when the internal pressure of the battery cell reaches a certain level, such as the first threshold, to provide overcharge protection, thereby improving the reliability of the battery. By setting the protrusion of the first protrusion from the main body to be less than or equal to 5mm, the space occupied by the first protrusion can be reduced, thereby reducing the impact on the battery's volumetric energy density. To this end, by setting the protrusion of the first protrusion from the main body to be greater than or equal to 0.1mm and less than or equal to 5mm, the reliability of the battery cell's overcharge protection and the battery's volumetric energy density can be balanced.

According to some embodiments of the present application, along the thickness direction of the first wall, the dimension of the first protrusion protruding from the main body is greater than or equal to 0.5 mm and less than or equal to 3 mm.

In the above solution, by setting the protrusion of the first protrusion from the main body to be greater than or equal to 0.5mm, the structural strength of the first wall is further improved, allowing the first deformable member to efficiently contact the first electrode terminal when the internal pressure of the battery cell reaches a certain level, such as the first threshold, thereby providing overcharge protection and thereby improving the reliability of the battery. By setting the protrusion of the first protrusion from the main body to be less than or equal to 3mm, the space occupied by the first protrusion can be effectively reduced, thereby reducing the impact on the battery's volumetric energy density. To this end, by setting the protrusion of the first protrusion from the main body to be greater than or equal to 0.5mm and less than or equal to 3mm, the reliability of the battery cell's overcharge protection and the battery's volumetric energy density can be balanced.

According to some embodiments of the present application, the first insulating portion includes a first insulating member, at least a portion of which is arranged between a first portion of the first electrode terminal located on the outside of the first wall and the first wall, and the first insulating member is formed with a third through hole and a fourth through hole, and along the thickness direction of the first wall, the third through hole is arranged opposite to the first through hole, and the fourth through hole is arranged opposite to the second through hole.

In the above scheme, the first insulating member has a simple structure. On the one hand, the first electrode terminal is allowed to pass through the third through hole, so that the first electrode terminal is electrically connected to the electrode assembly and external charging and discharging is realized. The first deformable member is allowed to deform through the fourth through hole so as to contact the first part to realize overcharge protection. On the other hand, the first insulating member can effectively insulate and isolate the first part and the first wall, reducing the risk of internal short circuit of the battery cell due to short circuit between the first part and the first wall, thereby making the battery highly reliable.

According to some embodiments of the present application, the first insulating member includes a first body and a first flange, the first body is located between the first part and the first wall, the first flange is arranged on the surface of the first body facing away from the first wall, and the first flange surrounds at least part of the outer peripheral surface of the first part.

In the above solution, by setting the first body and the first flange, the first wall and the first part can be effectively insulated and isolated, so that there is a longer creepage distance between the first part and the first wall, and the first insulating member has higher insulation performance, effectively reducing the risk of internal short circuit of the battery cell due to short circuit between the first wall and the first electrode terminal, so that the battery has high reliability.

According to some embodiments of the present application, the first insulating member further includes a second flange, which is disposed around the third through hole and is located between a hole wall of the first through hole and the first electrode terminal.

In the above solution, by providing the second flange, the hole wall of the first through hole and the first electrode terminal can be effectively insulated and isolated, reducing the risk of the first electrode terminal contacting the hole wall of the first through hole and causing internal short circuit in the battery cell, thereby effectively improving the reliability of the battery.

According to some embodiments of the present application, the battery cell further includes a second electrode terminal, a second insulating portion, and a second deformable member. The second electrode terminal is disposed on the first wall and electrically connected to the electrode assembly. The second electrode terminal is used for input and output of electrical energy, and the second electrode terminal and the first electrode terminal have opposite polarities. The second insulating portion is disposed between the first wall and the second electrode terminal to insulate and isolate the second electrode terminal from the first wall. The second deformable member is electrically connected to the first wall and is configured to be deformable to contact the second electrode terminal to electrically connect the second electrode terminal to the first wall.

In the above scheme, on the one hand, by providing a second insulating portion between the first wall and the second electrode terminal, the first wall and the second electrode terminal can be effectively insulated and isolated, thereby reducing the risk of internal short circuit of the battery cell due to short circuit between the first wall and the second electrode terminal, and making the battery highly reliable; on the other hand, by providing a second deformable member, when the internal pressure of the battery cell reaches a certain level, such as a second threshold value, the second deformable member is deformed to contact the second electrode terminal, thereby electrically connecting the second electrode terminal to the second wall, and cooperating with the short circuit between the first deformable member and the first electrode terminal, the electrical connection component inside the battery cell is not short-circuited. The large current generated by the short circuit causes the fuse to cut off the charge and discharge circuit of the battery cell, thereby playing a role in overcharge protection and reducing the risk of thermal runaway of the battery cell, thereby making the battery have higher reliability; on the other hand, because the first electrode terminal and the second electrode terminal are both insulated and isolated from the first wall under non-abuse conditions, the outer shell of the battery cell can be uncharged, which is conducive to the battery cell forming an energy storage device, so that the risk of ignition and breakdown between two adjacent battery cells in the energy storage device is small. At the same time, by providing the second deformable member, the overcharge protection function can be effectively achieved, so that the energy storage device has high reliability.

According to some embodiments of the present application, the second electrode terminal is a negative electrode terminal, so that the minimum pressure value for deformation of the second deformation member is greater than the minimum pressure value for deformation of the first deformation member.

In the above scheme, when the second electrode terminal is the negative electrode terminal, by making the minimum pressure value that causes the second deforming member to deform greater than the minimum pressure value that causes the first deforming member to deform, the second deforming member can be deformed when the pressure inside the battery cell is greater than that of the first deforming member. On the one hand, the battery cell can have an overcharge protection function. On the other hand, it can reduce the risk of gas production inside the battery cell causing the second deforming member to flip over, resulting in the shell being negatively charged and corroded by the electrolyte under non-overcharge abuse conditions, thereby ensuring the integrity of the shell to a certain extent, reducing the risk of electrolyte leakage, and thus improving the reliability of the battery.

According to some embodiments of the present application, the first wall is formed with a fifth through hole and a sixth through hole, the second electrode terminal passes through the fifth through hole, the second deformable member closes the sixth through hole, and the second deformable member is configured to be deformable to partially pass through the sixth through hole to contact the second electrode terminal.

In the above scheme, when the internal pressure of the battery cell reaches a certain level, such as the second threshold value, the internal pressure of the battery cell can act on the second deformable member, so that the second deformable member deforms toward the outside of the first wall to effectively contact the third part of the second electrode terminal, and cooperates with the first deformable member to contact the first electrode terminal, so that the electrical connection component inside the battery cell is melted due to the large current generated by the short circuit, so as to cut off the charging and discharging circuit of the battery cell, thereby reducing the risk of thermal runaway of the battery cell, and thus making the battery have higher reliability.

According to some embodiments of the present application, along the thickness direction of the first wall, a projection of a third portion of the second electrode terminal located outside the first wall at least partially overlaps with a projection of the second deformable member.

In the above scheme, by arranging the second deformable member corresponding to the third part along the thickness direction of the first wall, when the pressure inside the battery cell reaches a certain level, such as the second threshold, the third part can be quickly contacted with a smaller deformation amount, thereby quickly electrically connecting the second electrode terminal and the first wall, and cooperating with the first deformable member to contact the first electrode terminal, the electrical connection component inside the battery cell is melted due to the large current generated by the short circuit, thereby cutting off the charge and discharge circuit of the battery cell, thereby reducing the risk of thermal runaway of the battery cell, and thus making the battery have higher reliability.

According to some embodiments of the present application, the first wall includes a main body portion and a second reinforcement portion connected to each other, and the third portion of the second electrode terminal located outside the first wall is disposed on the second reinforcement portion.

In the above scheme, by providing a second reinforcement portion, the overall strength of the first wall can be improved, and the risk of deformation of the first wall due to internal pressure of the battery cell or external impact, which causes the second deformable member to be unable to effectively contact the third part to conduct electricity between the second electrode terminal and the first wall, can be reduced. The second deformable member can effectively contact the second electrode terminal under abuse conditions such as overcharging of the battery cell, thereby effectively playing a role in overcharging protection, reducing the risk of thermal runaway of the battery cell, and making the battery have higher reliability.

According to some embodiments of the present application, the second reinforcing portion includes a second protrusion protruding from a surface of the body portion along the thickness direction of the first wall.

In the above solution, by providing a second protrusion to strengthen the structural strength of the first wall, the risk of deformation of the first wall due to internal pressure of the battery cell or external impact, which causes the second deformable member to be unable to effectively contact the third part to conduct electricity between the second electrode terminal and the first wall, can be effectively reduced, thereby making the battery more reliable.

According to some embodiments of the present application, the second reinforcement portion further includes a second recessed portion, which is arranged on another surface of the main body portion along the thickness direction of the first wall, and the second recessed portion is arranged opposite to the second protruding portion.

In the above scheme, a second recess is provided at a position corresponding to the second protrusion. On the one hand, the difficulty of forming the second protrusion can be reduced and material costs can be saved. On the other hand, if the second recess is on the inner side of the first wall, the space of the second recess can be used to accommodate more active substances or electrolytes, which is beneficial to the improvement of the energy density or charge and discharge performance of the battery cell. If the second recess is on the outer side of the first wall, the space of the second recess can be used to accommodate external structural parts, which is beneficial to the improvement of the battery volume energy density.

According to some embodiments of the present application, the second protrusion is located on the outside of the first wall, and a second positioning groove is formed on the second protrusion. The second positioning groove accommodates the third part to limit the movement of the third part.

In the above scheme, by setting the second positioning groove, the second electrode terminal can be effectively positioned and the displacement of the second electrode terminal can be limited. On the one hand, the risk of the second electrode terminal being separated from the internal electrical connection component of the battery cell and causing internal short circuit of the battery cell is reduced. On the other hand, the second electrode terminal can be effectively cooperated with the second deformable member to play the role of overcharge protection and improve the reliability of the battery.

According to some embodiments of the present application, the second protrusion is located on the outside of the first wall, and along the thickness direction of the first wall, the dimension of the second protrusion protruding from the main body is greater than or equal to 0.1 mm and less than or equal to 5 mm.

In the above solution, by setting the protrusion of the second protrusion from the main body to be greater than or equal to 0.1mm, the structural strength of the first wall can be effectively improved, allowing the second deformable member to effectively contact the second electrode terminal when the internal pressure of the battery cell reaches a certain level, such as the second threshold, to provide overcharge protection, thereby improving the reliability of the battery. By setting the protrusion of the second protrusion from the main body to be less than or equal to 5mm, the space occupied by the second protrusion can be reduced, thereby reducing the impact on the battery's volumetric energy density. To this end, by setting the protrusion of the second protrusion from the main body to be greater than or equal to 0.1mm and less than or equal to 5mm, the reliability of the battery cell overcharge protection and the battery's volumetric energy density can be balanced.

According to some embodiments of the present application, along the thickness direction of the first wall, the dimension of the second protrusion protruding from the main body is greater than or equal to 0.5 mm and less than or equal to 3 mm.

In the above solution, by setting the protrusion of the second protrusion from the main body to be greater than or equal to 0.5mm, the structural strength of the first wall is further improved, allowing the second deformable member to effectively contact the second electrode terminal when the internal pressure of the battery cell reaches a certain level, such as the second threshold, to provide overcharge protection, thereby improving the reliability of the battery. By setting the protrusion of the second protrusion from the main body to be less than or equal to 3mm, the space occupied by the second protrusion can be effectively reduced, thereby reducing the impact on the battery's volumetric energy density. To this end, by setting the protrusion of the second protrusion from the main body to be greater than or equal to 0.5mm and less than or equal to 3mm, the reliability of the battery cell overcharge protection and the volumetric energy density of the battery can be balanced.

According to some embodiments of the present application, the second insulating portion includes a second insulating member, at least a portion of which is arranged between the third portion and the first wall, and the second insulating member is formed with a seventh through hole and an eighth through hole. Along the thickness direction of the first wall, the seventh through hole is arranged opposite to the fifth through hole, and the eighth through hole is arranged opposite to the sixth through hole.

In the above scheme, the second insulating member has a simple structure. On the one hand, the second electrode terminal is allowed to pass through the seventh through hole, so that the second electrode terminal is electrically connected to the electrode assembly and external charging and discharging is realized. The second deformable member is allowed to deform through the eighth through hole so as to contact the third part to achieve overcharge protection. On the other hand, the second insulating member can effectively insulate and isolate the third part and the first wall, reducing the risk of internal short circuit of the battery cell due to short circuit between the third part and the first wall, thereby making the battery highly reliable.

According to some embodiments of the present application, the second insulating member includes a second body and a third flange, the second body is located between the third part and the first wall, the third flange is arranged on the surface of the second body facing away from the first wall, and the third flange surrounds at least part of the outer peripheral surface of the third part.

In the above solution, by providing the second body and the third flange, the first wall and the third part can be effectively insulated and isolated, so that there is a longer creepage distance between the third part and the first wall, and the second insulating member has higher insulation performance, effectively reducing the risk of internal short circuit of the battery cell due to short circuit between the first wall and the second electrode terminal, thereby increasing the reliability of the battery.

According to some embodiments of the present application, the second insulating member further includes a fourth flange, which is arranged around the seventh through hole and is located between the hole wall of the fifth through hole and the second electrode terminal.

In the above solution, by providing the fourth flange, the hole wall of the fifth through hole and the second electrode terminal can be effectively insulated and isolated, reducing the risk of the second electrode terminal contacting the hole wall of the fifth through hole and causing internal short circuit in the battery cell, thereby effectively improving the reliability of the battery.

According to some embodiments of the present application, the resistance value of the second insulating portion is greater than or equal to 200 megohms.

In the above solution, by setting the resistance value of the second insulating portion to be greater than or equal to 200 megohms, the high-voltage insulation resistance between the second electrode terminal and the first wall can be effectively improved, which can effectively meet the insulation voltage requirements of the energy storage device and reduce the risk of external voltage breaking through the second insulating portion and conducting the first wall and the second electrode terminal, causing an internal short circuit in the battery cell, thereby making the energy storage device more reliable.

According to some embodiments of the present application, the resistance value of the first insulating portion is greater than or equal to 200 megohms.

In the above solution, by setting the resistance value of the first insulating portion to be greater than or equal to 200 megohms, the high-voltage insulation resistance between the first electrode terminal and the first wall can be effectively improved, which can effectively meet the insulation voltage requirements of the energy storage device and reduce the risk of external voltage breaking through the first insulating portion, connecting the first wall and the first electrode terminal, and causing an internal short circuit in the battery cell, thereby making the energy storage device more reliable.

According to some embodiments of the present application, the housing includes a shell and an end cover, wherein the shell has an opening. The first wall is the end cover, which is connected to the shell and closes the opening.

In the above solution, the shell structure is simple, which facilitates the assembly of battery cells and helps improve battery manufacturing efficiency.

According to some embodiments of the present application, a first insulating layer is provided on the inner wall of the shell.

In the above solution, by providing a first insulating layer inside the shell, the electrolyte inside the shell can be effectively insulated and isolated from the inner wall of the shell, thereby reducing the risk of the shell being corroded by the electrolyte and the risk of electrolytic wire leakage, making the battery more reliable.

According to some embodiments of the present application, the first insulating layer is an insulating coating provided on the inner wall of the shell.

In the above scheme, by providing an insulating coating on the inner wall of the shell, on the one hand, the electrolyte and the shell can be effectively separated, the electrolyte ion path between the motor assembly and the shell can be cut off, and the risk of shell corrosion can be reduced; on the other hand, the first insulating layer can be efficiently formed on the inner wall of the shell by spraying or other methods, so that the manufacturing efficiency of the battery is high; on the other hand, the insulating coating has high mechanical strength, which can effectively reduce the puncture of metal particles introduced by the manufacturing process, resulting in electrical connection between the electrode assembly and the shell, causing the risk of internal short circuit of the battery cell or the risk of corrosion of the shell, so that the battery has high reliability.

According to some embodiments of the present application, along the first direction, the inner wall of the shell includes a blank area and an insulating area connected in sequence, the insulating area is provided with a first insulating layer, the blank area is connected to the first wall, and the first direction is parallel to the first wall and points to the direction of the electrode assembly.

In the above solution, by providing a blank area, the effect of the first insulating layer on the connection between the shell and the first wall can be reduced. For example, the first wall and the shell are welded to each other, and by providing a blank area, the welding quality between the first wall and the shell can be improved, thereby improving the quality of the battery.

According to some embodiments of the present application, along the second direction, the projection of the electrode assembly on the inner wall of the shell does not overlap with the blank area, and the second direction is perpendicular to the first direction.

In the above scheme, by staggering the electrode assembly and the blank area, the risk of internal short circuit of the battery cell or corrosion of the outer shell by the electrolyte due to negative charge caused by overlapping of the electrode assembly and the blank area can be reduced, which can effectively improve the reliability of the battery cell and thus improve the reliability of the battery.

According to some embodiments of the present application, the thickness of the first insulating layer is greater than or equal to 60 μm and less than or equal to 200 μm.

In the above solution, by setting the thickness of the first insulating layer to be greater than or equal to 60μm, the first insulating layer can have high mechanical strength and insulation performance, effectively isolating the shell from the electrolyte, reducing the risk of the shell being corroded by the electrolyte due to negative charge, and thus making the battery more reliable. By setting the thickness of the first insulating layer to be less than or equal to 200μm, the first insulating layer can effectively reduce the internal space occupied by the battery cell, making the battery cell have a higher volumetric energy density, and thus the battery has a higher volumetric energy density. To this end, by setting the thickness of the first insulating layer to be greater than or equal to 60μm and less than or equal to 200μm, both battery reliability and volumetric energy density can be taken into account.

According to some embodiments of the present application, the thickness of the first insulating layer is greater than or equal to 80 μm and less than or equal to 130 μm.

In the above solution, by setting the thickness of the first insulating layer to be greater than or equal to 80μm, the first insulating layer can further have higher mechanical strength and insulation performance, effectively isolating the shell and the electrolyte, reducing the risk of the shell being corroded by the electrolyte due to negative charge, and making the battery more reliable. By setting the thickness of the first insulating layer to be less than or equal to 130μm, the first insulating layer can further reduce the internal space occupied by the battery cell, making the battery cell have a higher volume energy density, and thus the battery has a higher volume energy density. To this end, by setting the thickness of the first insulating layer to be greater than or equal to 80μm and less than or equal to 130μm, it is possible to effectively balance the reliability and volume energy density of the battery.

According to some embodiments of the present application, a second insulating layer is provided on the outer surface of the shell.

In the above solution, by providing a second insulating layer on the outer surface of the shell, the shell can be effectively insulated and protected, reducing the risk of corrosion by the electrolyte due to negative charge of the shell, so that the battery has higher reliability.

In a second aspect, some embodiments of the present application provide a battery, comprising the battery cell provided in the first aspect of claim 1.

In a third aspect, some embodiments of the present application provide an energy storage device comprising the battery cell provided in the first aspect.

In a fourth aspect, some embodiments of the present application provide an electrical device, comprising the battery cell provided in the first aspect, wherein the battery cell is used to provide electrical energy.

Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

FIG1 is a schematic diagram of a vehicle in some embodiments of the present application;

FIG2 is a schematic diagram of an energy storage device in some embodiments of the present application;

FIG3 is an exploded perspective view of a battery in some embodiments of the present application;

FIG4 is an exploded perspective view of a battery cell in some embodiments of the present application;

FIG5 is a perspective exploded view of a partial structure of a battery cell in some embodiments of the present application;

FIG6 is a top view of a partial structure of a battery cell in some embodiments of the present application;

FIG7 is a cross-sectional view taken along the line A-A in FIG6 ;

FIG8 is a schematic diagram of a first wall and a first electrode terminal in some embodiments of the present application;

FIG9 is a schematic diagram of a first deformable member in some embodiments of the present application;

FIG10 is a perspective view of a first wall in some embodiments of the present application;

FIG11 is a schematic diagram of a partial structure of a first wall in some embodiments of the present application;

FIG12 is a schematic diagram of a first wall and a second electrode terminal in some embodiments of the present application;

FIG13 is a schematic diagram of a second deformable member in some embodiments of the present application;

FIG14 is a partial schematic diagram of the first wall in some embodiments of the present application;

FIG15 is a schematic diagram of a housing and an electrode assembly in some embodiments of the present application;

FIG16 is a schematic diagram of a housing and a first insulating layer in some embodiments of the present application;

FIG17 is a schematic diagram of the shell and the first insulating layer in some other embodiments of the present application.

Icons: 10 - battery cell; 11 - housing; 110 - first wall; 111 - housing; 1100 - first through hole; 1101 - second through hole; 1102 - fifth through hole; 1103 - sixth through hole; 110a - body; 110b - first reinforcement; 110b0 - first convex portion; 110b1 - first concave portion; 110b2 - first positioning groove; 110c - second reinforcement; 110c0 - second convex portion; 110c1 - second concave portion; 110c2 - second positioning groove; 12 - electrode assembly; 120 - first electrode tab; 121 - second electrode tab; 123 - first adapter; 124 - second adapter; 13 - first electrode terminal; 130 - first portion; 131 - second portion; 14 - first insulating portion; 140 - first insulating member; 1400 - first body; 14001 - third through hole; 14002 - fourth through hole; 1401 - first flange; 1402 - second flange; 14 1-first sealing portion; 15-first deforming member; 150-first skirt; 151-first flip foil; 152-first electrical connection portion; 16-second electrode terminal; 160-third portion; 161-fourth portion; 17-second insulating portion; 170-second insulating member; 1700-second body; 17001-seventh through hole; 17002-eighth through hole; 1701-third flange; 1702-fourth flange; 171-second sealing portion; 18- Second deformable member; 180-second skirt; 181-second flip foil; 182-second electrical connection portion; 19-first insulating layer; 19a-second insulating layer; 19b-blank area; z-thickness direction of the first wall; y-first direction; x-second direction; 1000-vehicle; 100-battery; 200-controller; 300-motor; 2000-energy storage device; 2001-cabinet; 20-box; 21-first box part; 22-second box part.

DETAILED DESCRIPTION

The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of this application, the term "and/or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and/or B can represent the following three situations: A exists, A and B exist at the same time, and B exists. In addition, the character "/" in this document generally indicates that the associated objects are in an "or" relationship.

In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

In the present application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries or magnesium-ion batteries, etc., which are not limited in the embodiments of the present application. Battery cells may be rectangular or in other shapes, etc., which are not limited in the embodiments of the present application. The battery mentioned in the embodiments of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. The battery generally includes a casing for encapsulating one or more battery cells. The casing can prevent liquids or other foreign matter from affecting the charging or discharging of the battery cells.

A battery cell includes an electrode assembly and an electrolyte. The electrode assembly consists of a positive electrode sheet, a negative electrode sheet, and a separator. A battery cell primarily operates by the movement (e.g., deintercalation) of metal ions between the positive and negative electrode sheets. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive electrode collector. The positive electrode collector not coated with the positive active material layer protrudes from the positive electrode collector coated with the positive active material layer, and the positive electrode collector not coated with the positive active material layer serves as the positive electrode tab. For lithium-ion batteries, for example, the positive electrode current collector can be made of aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. The negative electrode sheet includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative electrode collector. The negative electrode collector not coated with the negative active material layer protrudes from the negative electrode collector coated with the negative active material layer, and the negative electrode collector not coated with the negative active material layer serves as the negative electrode tab. The negative electrode current collector can be made of copper, and the negative electrode active material can be carbon or silicon, among others. To ensure that high currents can flow without fusing, multiple positive electrode tabs are stacked together, and multiple negative electrode tabs are stacked together. The separator can be made of materials such as PP (polypropylene) or PE (polyethylene). Furthermore, the electrode assembly can be a wound or laminated structure, although the embodiments of the present application are not limited thereto.

The battery cell also includes a housing, an electrode assembly and an electrolyte disposed inside the housing. The housing has a first wall, and the first wall is provided with an electrode terminal connected to the electrode assembly, and the electrode terminal is used for input and output of electrical energy.

The development of battery technology must take into account multiple design factors at the same time, such as energy density, cycle life, discharge capacity, charge and discharge rate and other performance parameters. In addition, battery reliability must also be considered.

With the development of battery technology, the operating voltage of batteries is getting higher and higher. For a single battery cell, the high voltage can easily conduct the first wall and the electrode terminal, causing an internal short circuit in the battery cell and affecting the reliability of the battery.

In view of this, in order to improve the problem of short circuit between the first wall and the electrode terminal, which causes an internal short circuit in the battery cell and affects the reliability of the battery, some embodiments of the present application provide a battery cell. The battery cell includes a housing, an electrode assembly, a first electrode terminal and a first insulating portion. The housing has a first wall. The electrode assembly is disposed within the housing. The first electrode terminal is disposed on the first wall and electrically connected to the electrode assembly, and the first electrode terminal is used for input and output of electrical energy. The first insulating portion is disposed between the first wall and the first electrode terminal to insulate and isolate the first electrode terminal from the first wall.

In the above solution, by providing the first insulating portion between the first wall and the first electrode terminal, the first wall and the first electrode terminal can be effectively insulated and isolated, reducing the risk of internal short circuits in the battery cells due to a short circuit between the first wall and the first electrode terminal, thereby enhancing battery reliability. In particular, in energy storage devices operating at higher voltages, providing the first insulating portion between the first wall and the first electrode terminal can effectively reduce the risk of thermal runaway of the energy storage device due to the remaining battery cells in the battery running out of control, causing the outer casing to be charged with high voltage, resulting in the high voltage electricity flowing through the first wall and the electrode terminal, causing an internal short circuit in the battery cells.

The technical solutions described in the embodiments of the present application are applicable to batteries, energy storage devices using batteries, and electrical devices using batteries.

The energy storage device may include an energy storage container, an energy storage cabinet, etc. For example, the energy storage cabinet may include a cabinet body and one or more batteries disposed on the cabinet body.

The electrical device can be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, etc. The vehicle can be a new energy vehicle, which can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, etc. The spacecraft includes airplanes, rockets, space shuttles, and spacecraft, etc. The electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. The electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. The electrical devices in the embodiments of the present application include but are not limited to those mentioned above.

For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device.

FIG1 is a schematic diagram of a vehicle in some embodiments of the present application.

A controller 200, a motor 300, and a battery 100 may be provided inside the vehicle 1000. The controller 200 is used to control the battery 100 to power the motor 300. For example, the battery 100 may be provided at the bottom, front, or rear of the vehicle 1000. The battery 100 may be used to power the vehicle 1000. For example, the battery 100 may serve as an operating power source for the vehicle 1000 and for the circuit system of the vehicle 1000, for example, for the starting, navigation, and operating power requirements of the vehicle 1000. In another embodiment of the present application, the battery 100 may serve not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

Please refer to FIG2 , which is a schematic diagram of an energy storage device in some embodiments of the present application.

The energy storage device 2000 may include a cabinet 2001 and a plurality of batteries 100. The plurality of batteries 100 may be disposed in the cabinet 2001. The plurality of batteries 100 may be connected in series, in parallel, or in a mixed manner.

Please refer to FIG3 , which is a three-dimensional exploded view of the battery 100 in some embodiments of the present application.

The battery 100 includes a battery cell 10 and a housing 20, wherein the battery cell 10 is housed within the housing 20. The housing 20 is used to provide a storage space for the battery cell 10, and the housing 20 can adopt a variety of structures. In some embodiments, the housing 20 can include a first housing portion 21 and a second housing portion 22, wherein the first housing portion 21 and the second housing portion 22 overlap each other, and the first housing portion 21 and the second housing portion 22 jointly define a storage space for accommodating the battery cell 10. The second housing portion 22 can be a hollow structure with one end open, and the first housing portion 21 can be a plate-like structure, with the first housing portion 21 overlapping the open side of the second housing portion 22, so that the first housing portion 21 and the second housing portion 22 jointly define a storage space; the first housing portion 21 and the second housing portion 22 can also be hollow structures with one end open, with the open side of the first housing portion 21 overlapping the open side of the second housing portion 22. Of course, the box body 20 formed by the first box body portion 21 and the second box body portion 22 can be in various shapes, such as a cylinder, a cuboid, etc.

In the battery 100 , there may be one or more battery cells 10 , and each battery cell 10 may be fixed to the case 20 via a connector (such as a bolt), or each battery cell 10 may be fixed to the case 20 by bonding.

Please refer to Figures 4 to 8. Figure 4 is a three-dimensional exploded view of the battery cell 10 in some embodiments of the present application, Figure 5 is a three-dimensional exploded view of the local structure of the battery cell 10 in some embodiments of the present application, Figure 6 is a top view of the local structure of the battery cell 10 in some embodiments of the present application, Figure 7 is a cross-sectional view taken along the A-A direction in Figure 6, and Figure 8 is a schematic diagram of the first wall and the first electrode terminal in some embodiments of the present application.

The battery cell 10 includes a housing 11, an electrode assembly 12, a first electrode terminal 13, and a first insulating portion 14. The housing 11 has a first wall 110. The electrode assembly 12 is disposed within the housing 11. The first electrode terminal 13 is disposed on the first wall 110 and electrically connected to the electrode assembly 12. The first electrode terminal 13 is used for inputting and outputting electrical energy. The first insulating portion 14 is disposed between the first wall 110 and the first electrode terminal 13 to insulate and isolate the first electrode terminal 13 from the first wall 110.

The housing 11 is a component for accommodating the electrode assembly 12. The housing 11 can also be used to accommodate an electrolyte, such as an electrolyte. Referring to Figure 4, in some embodiments, the housing 11 includes a shell 111 and an end cap. A accommodating cavity is formed inside the shell 111, and the accommodating cavity is used to accommodate the electrode assembly 12. The shell 111 has an opening connected to the accommodating cavity. The end cap is covered at the opening of the shell 111 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 12 and the electrolyte. The end cap can be connected to the shell 111 by welding, bonding, clamping or other connection methods. Optionally, the housing 11 may also include a bottom plate, and openings are respectively formed at both ends of the shell 111, one of the openings is closed by the end cap, and the other opening is closed by the bottom plate.

In some embodiments, the material of the shell 11 can be metal or a combination of metal and non-metal. For example, the shell 11 can be made of metal, such as aluminum, copper, iron, steel or aluminum alloy; for example, part of the shell 11 can be made of metal, and the rest can be made of non-metal, such as the end cover of the shell 11 can be made of metal, and the shell 111 or other parts of the shell 11 can be made of non-metallic materials.

In some embodiments, when assembling the battery cell 10, the electrode assembly 12 may be placed in the housing 111 first, and the housing 111 may be filled with electrolyte, and then the end cap may be attached to the opening of the housing 111 to complete the assembly of the battery cell 10. Alternatively, in some embodiments, when assembling the battery cell 10, the electrode assembly 12 may be placed in the housing 111 first, and then the end cap may be attached to the opening of the housing 111, and then the housing 111 may be filled with electrolyte through the injection hole on the end cap, and then the injection hole may be closed to complete the assembly of the battery cell 10.

The housing 11 can have various shapes, such as a cylindrical or prismatic structure. The shape of the housing 11 can be determined based on the specific shape of the electrode assembly 12. For example, if the electrode assembly 12 has a cylindrical structure, a cylindrical housing 11 can be selected. If the electrode assembly 12 has a flat structure, the housing 11 can be square.

First wall 110 is part of the housing 11. It can support first electrode terminal 13, ensuring a stable ground state for electrical energy input and output. In some embodiments, first wall 110 can be part of housing 111, such as a side wall or bottom wall of housing 111. In some embodiments, first wall 110 can serve as an end cap.

The first electrode terminal 13 is a component mounted on the first wall 110. The first electrode terminal 13 is used to electrically connect to the electrode assembly 12 so that current flows into or out of the first electrode tab 120 through the first electrode terminal 13. The polarity of the first electrode terminal 13 and the first electrode tab 120 is the same. In some embodiments, the first electrode terminal 13 is made of a metal material, such as aluminum, copper, iron, aluminum, steel, an alloy, or a composite metal. In some embodiments, the first electrode terminal 13 can be connected to the first electrode tab 120 through a first adapter 123. Exemplarily, the first electrode tab 120 of the electrode assembly 12 is composed of a plurality of first sub-tabs stacked together. After welding one end of the first adapter 123 to the first electrode tab 120, the other end of the first adapter 123 can be welded to the first electrode terminal 13.

The first insulating portion 14 has a high resistance, insulating the first electrode terminal 13 from the first wall 110. For example, referring to FIG5 , the first electrode terminal 13 has an exposed first portion 130. The first insulating portion 14 can be disposed between the outer side of the first wall 110 and the first portion 130 to insulate the first electrode terminal 13 from the first wall 110. In some embodiments, the first insulating portion 14 can cover the outer periphery of the first portion 130 to increase the creepage distance between the first electrode terminal 13 and the first wall 110.

For example, in some embodiments, a first through-hole 1100 is formed in the first wall 110. The first electrode terminal 13 can pass through the first through-hole 1100 to form a first portion 130 on the outside and a second portion 131 on the inside. The first portion 130 is used to connect to an external electrical connection member, and the second portion 131 is used to electrically connect to the electrode assembly 12. The first insulating portion 14 has a third through-hole 14001 formed in correspondence with the first through-hole 1100 for the first electrode terminal 13 to pass through. Alternatively, a major portion of the first insulating portion 14 is located between the first portion 130 and the first wall 110, while some portion of the first insulating portion 14 may be located between the first through-hole 1100 and the first electrode terminal 13. Alternatively, a major portion of the first insulating portion 14 is located between the first portion 130 and the first wall 110, while some portion of the first insulating portion 14 may be located between the first through-hole 1100 and the first electrode terminal 13, with the remaining portion of the first insulating portion 14 further located between the first wall 110 and the second portion 131.

In some embodiments, the first insulating portion 14 may be in a plate shape as a whole, and its two opposite surfaces are relatively flat so as to be stably positioned between the first electrode terminal 13 and the first wall 110 .

In some embodiments, the first insulating portion 14 can be made of a material with a relatively high resistance, such as an organic insulating material, an inorganic insulating material, or a mixed insulating material. For example, in some embodiments of the present application, the material of the first insulating portion 14 can include an insulating PPS (polyphenylene sulfide) material. In other embodiments, the first insulating portion 14 can also be made of other materials with insulating properties, such as polypropylene and polyethylene.

In some embodiments, the resistance value of the first insulating portion 14 can be measured in megohms (MΩ). For example, in the battery cell 10 provided in some embodiments of the present application, the resistance value of the first insulating portion 14 can be greater than or equal to 200 MΩ. In other embodiments, the resistance value of the first insulating portion 14 can be other values, such as 1 MΩ, 10 MΩ, 20 MΩ, 30 MΩ, 40 MΩ, 50 MΩ, 60 MΩ, 70 MΩ, 80 MΩ, 90 MΩ, 100 MΩ, 110 MΩ, 120 MΩ, 130 MΩ…210 MΩ, 220 MΩ, 230 MΩ, etc.

In the above solution, by providing the first insulating portion 14 between the first wall 110 and the first electrode terminal 13, the first wall 110 and the first electrode terminal 13 can be effectively insulated and isolated, reducing the risk of internal short circuits in the battery cells 10 due to a short circuit between the first wall 110 and the first electrode terminal 13, thereby enhancing battery reliability. In particular, in energy storage devices operating at higher voltages, providing the first insulating portion 14 between the first wall 110 and the first electrode terminal 13 can effectively reduce the risk of thermal runaway of the energy storage device due to the remaining battery cells 10 in the battery running out of control, causing the outer casing 11 to be charged with high voltage, resulting in the high voltage electricity flowing through the first wall 110 and the electrode terminal, causing an internal short circuit in the battery cells 10.

According to some embodiments of the present application, please refer to Figures 5, 8, and 9. Figure 9 is a schematic diagram of the first deformable member 15 in some embodiments of the present application. The battery cell 10 also includes the first deformable member 15, which is electrically connected to the first wall 110. The first deformable member 15 is configured to be deformable to contact the first electrode terminal 13 to electrically connect the first electrode terminal 13 to the first wall 110.

The first deformable member 15 is mounted on the first wall 110 and is electrically connected to the first wall 110. In some embodiments, the first deformable member 15 can be made of a metal material, such as aluminum, copper, iron, aluminum, steel, an alloy, or a composite metal. In some embodiments, the first deformable member 15 can be welded to the inner side of the first wall 110.

The first deformable member 15 is a structural member that deforms due to the internal pressure of the battery cell 10. The first deformable member 15 is used to protect the battery cell 10 from overcharge. For example, when the battery cell 10 is subjected to an abuse condition such as overcharge, the internal pressure increases. When the internal pressure reaches a first threshold, the first deformable member 15 deforms to contact the first electrode terminal 13, thereby electrically connecting the first wall 110 and the first electrode terminal 13, short-circuiting the positive and negative electrodes within the battery cell 10.

In some embodiments, the portion of the first deformable member 15 that is deformed by pressure to contact the first electrode terminal 13 may be the inner portion of the first electrode terminal 13 on the first wall 110, or the portion of the first electrode terminal 13 on the outer side of the first wall 110. For example, the first deformable member 15 can be deformed and connected to the second portion 131 when the internal pressure of the battery cell 10 reaches the first threshold value. For another example, the first deformable member 15 can be deformed and connected to the first portion 130 when the internal pressure of the battery cell 10 reaches the first threshold value.

In some embodiments, the first deformable member 15 may be a flip sheet that flips under pressure. For example, referring to Figures 5 and 9 , the first deformable member 15 has a disc-shaped outer profile and comprises, from the outside inward, a first skirt 150, a first flip foil 151, and a first electrical connection portion 152, which are sequentially connected. The first skirt 150 can be connected to the first wall 110. The first flip foil 151 is relatively thin and is designed to deform and flip under pressure. After the first flip foil 151 flips, it can push the first electrical connection portion 152 toward the first electrode terminal 13, thereby bringing the first electrical connection portion 152 into contact with the first electrode terminal 13.

For example, the first wall 110 has a second through hole 1101, and the first skirt 150 is welded to the first wall 110, so that the first deformable member 15 closes the second through hole 1101. In its natural state, the first flip foil 151 is collapsed away from the first wall 110. When the pressure inside the battery cell 10 reaches a certain level, such as a first threshold, the first flip foil 151 flips toward the first wall 110 to push the first electrical connection portion 152, thereby allowing the first electrical connection portion 152 to pass through the second through hole 1101 and contact the first portion 130.

In some embodiments, the first electrode terminal 13 is electrically connected to the first tab 120 via a first adapter 123. The second tab 121 of the electrode assembly 12 can be electrically connected to the outer casing 11. The second tab 121 has opposite polarity to the first tab 120. For example, the second tab 121 is connected to the outer casing 11 directly or via a second adapter 124, or the outer casing 11 is provided with a second electrode terminal 16, which is electrically connected to the outer casing 11, and the second tab 121 is connected to the second electrode terminal 16 directly or via a second adapter 124. When the internal pressure of the battery cell 10 reaches a first threshold, the first deformable member 15 deforms, short-circuiting the first electrode terminal 13 and the outer casing 11. This creates an internal short circuit between the positive and negative electrodes of the battery cell 10. The instantaneous high current generated can melt the electrical connection components within the battery cell 10, severing the charge and discharge circuit of the battery cell 10, thereby providing overcharge protection. The melted electrical connection components may include the first adapter 123 and/or the second adapter 124. Illustratively, the first adapter 123 includes a first fuse portion, and the flow area of the first fuse portion can be smaller than the flow area of the remaining portion of the first adapter 123. This allows the first fuse portion to melt when a relatively large current flows through it, thereby disconnecting the current path between the first tab 120 and the first electrode terminal 13. Illustratively, the second adapter 124 includes a second fuse portion, and the flow area of the second fuse portion can be smaller than the flow area of the remaining portion of the second adapter 124. This allows the second fuse portion to melt when a relatively large current flows through it, thereby disconnecting the current path between the second tab 121 and the second electrode terminal 16 or the housing 11.

In other embodiments, the first electrode terminal 13 is electrically connected to the first electrode tab 120 via a first adapter 123, and the second electrode tab 121 of the electrode assembly 12 can be electrically connected to the second electrode terminal 16. The second electrode tab 121 has an opposite polarity to the first electrode tab 120, and the second electrode terminal 16 can be insulated and mounted to the housing 11, for example, to the first wall 110 of the housing 11. The second electrode tab 121 can be electrically connected to the second electrode terminal 16 via a second adapter 124. A second deformable member 18 is provided corresponding to the second electrode terminal 16. The second deformable member 18 is electrically connected to the housing 11 and is configured to deform to contact the second electrode terminal 16 to electrically connect the second electrode terminal 16 to the housing 11. For example, the second deformable member 18 is configured to deform to contact the second electrode terminal 16 when the internal pressure of the battery cell 10 reaches a second threshold value to electrically connect the second electrode terminal 16 to the housing 11.

When the internal pressure of the battery cell 10 reaches a certain level, such as a first threshold, the first deformable member 15 deforms, short-circuiting the first electrode terminal 13 and the outer shell 11. When the internal pressure of the battery cell 10 reaches a second threshold, the second deformable member 18 deforms, short-circuiting the second electrode terminal 16 and the outer shell 11, thereby short-circuiting the positive and negative electrodes within the battery cell 10 and creating an internal short circuit. The large current generated instantaneously can melt the electrical connection components within the battery cell 10, cutting off the charge and discharge circuit of the battery cell 10, thereby providing overcharge protection. The fused electrical connection components can include the first adapter 123 and/or the second adapter 124. For example, the first adapter 123 has a first fuse portion, the flow area of which can be smaller than the flow area of the remaining portions of the first adapter 123, so that when a large current passes through, the first fuse portion can melt, thereby disconnecting the current path between the first tab 120 and the first electrode terminal 13. Exemplarily, the second adapter 124 has a second fuse portion, and the flow area of the second fuse portion can be smaller than the flow area of the rest of the second adapter 124, so that when a larger current passes through, the second fuse portion can be melted, thereby disconnecting the current path between the second electrode tab 121 and the second electrode terminal 16.

In the above scheme, by providing the first deformable member 15, when the internal pressure of the battery cell 10 reaches a certain level, such as the first threshold value, the first deformable member 15 is deformed to contact the first electrode terminal 13, so that the first electrode terminal 13 is electrically connected to the first wall 110, thereby realizing an internal short circuit of the battery cell 10, so that the electrical connection components inside the battery cell 10 are melted due to the large current generated by the short circuit, thereby cutting off the charge and discharge circuit of the battery cell 10, thereby playing a role of overcharge protection, and playing a role of reducing the risk of thermal runaway of the battery cell 10, thereby making the battery have higher reliability.

According to some embodiments of the present application, please refer to Figures 8, 10 and 11. Figure 10 is a three-dimensional diagram of the first wall 110 in some embodiments of the present application, and Figure 11 is a schematic diagram of the local structure of the first wall 110 in some embodiments of the present application.

The first wall 110 is formed with a first through hole 1100 and a second through hole 1101 through which the first electrode terminal 13 passes. The first deformable member 15 closes the second through hole 1101 and is configured to be deformable to partially pass through the second through hole 1101 and contact the first electrode terminal 13.

In some embodiments, along the thickness direction z of the first wall, the first electrode terminal 13 includes a first portion 130 located outside the first wall 110 and a second portion 131 at least partially located inside the first wall 110. The second portion 131 is used to electrically connect to the electrode assembly 12 of the battery cell 10.

In some embodiments, the first wall 110 may be an end cap of the housing 11 and may be plate-shaped. A first through-hole 1100 and a second through-hole 1101 are formed along the thickness direction z of the first wall 110. The first through-hole 1100 allows the first electrode terminal 13 to pass through, while the second through-hole 1101 allows the first deformable member 15 to pass through.

For example, referring to FIG8 , the first electrode terminal 13 includes a first portion 130 and a second portion 131. The first portion 130 is located outside the first wall 110 and can be flat for electrical connection to external structures. A portion of the second portion 131 is located inside the first wall 110 for electrical connection to the electrode assembly 12, while another portion of the second portion 131 passes through a first through-hole 1100 to connect to the first portion 130. The connection between the second portion 131 and the first portion 130 includes, but is not limited to, welding, bonding, riveting, or screwing. In other embodiments, the first portion 130 can be partially located outside the first wall 110, while another portion of the first portion 130 passes through the first through-hole 1100 to connect to the second portion 131. In other embodiments, the first portion 130 can be partially located outside the first wall 110, while a portion of the second portion 131 is located inside the first wall 110. Another portion of the first portion 130 and another portion of the second portion 131 are located within the first through-hole 1100 and connected to each other.

"First deformable member 15 encloses second through-hole 1101" may mean that first deformable member 15 closes second through-hole 1101, thereby enclosing electrode assembly 12 and electrolyte. In some embodiments, first skirt 150 of first deformable member 15 is disposed around the edge of second through-hole 1101 and welded to the inner side of first wall 110.

In some embodiments, when the internal pressure of the battery cell 10 reaches a first threshold, the first deformation member 15 can be deformed toward the first portion 130 to pass through the second through hole 1101 and contact the first portion 130 .

In some embodiments, the second through hole 1101 can be a stepped hole, which can provide a connection portion for the first skirt 150 of the first deformable member 15, so that the first skirt 150 can be accommodated in the second through hole 1101, reducing the occupation of the internal space of the battery cell 10 by the first deformable member 15.

In the above scheme, when the internal pressure of the battery cell 10 reaches a certain level, such as the first threshold value, the internal pressure of the battery cell 10 can act on the first deformable member 15, so that the first deformable member 15 is deformed toward the outside of the first wall 110 to effectively contact the first part 130 of the first electrode terminal 13, thereby effectively realizing an internal short circuit of the battery cell 10, so that the electrical connection components inside the battery cell 10 are melted due to the large current generated by the short circuit, so as to cut off the charge and discharge circuit of the battery cell 10, thereby reducing the risk of thermal runaway of the battery cell 10, and thus making the battery have higher reliability.

According to some embodiments of the present application, referring to FIG. 8 , along the thickness direction z of the first wall, the projection of the first portion 130 of the first electrode terminal 13 located outside the first wall 110 at least partially overlaps with the projection of the first deformable member 15 .

In some embodiments, the first part 130 is larger in size, and along the thickness direction z of the first wall, a portion of the first part 130 can be set opposite the second part 131 to be connected to the second part 131, and a portion of the first part 130 can be opposite the first deformable member 15 to directly contact the first deformable member 15 when the first deformable member 15 is deformed.

In some embodiments, along the thickness direction z of the first wall, the projection of the first deformable member 15 may entirely fall on the first portion 130. In other embodiments, along the thickness direction z of the first wall, the projection of the first deformable member 15 may partially fall on the first portion 130, while another portion may be offset from the first portion 130.

In the above scheme, by arranging the first deformable member 15 along the thickness direction z of the first wall corresponding to the first part 130, when the internal pressure of the battery cell 10 reaches a certain level, such as the first threshold, it can quickly contact the first part 130 with a smaller deformation amount, thereby quickly electrically connecting the first electrode terminal 13 and the first wall 110, thereby effectively realizing an internal short circuit of the battery cell 10, so that the electrical connection components inside the battery cell 10 are melted due to the large current generated by the short circuit, thereby cutting off the charge and discharge circuit of the battery cell 10, thereby reducing the risk of thermal runaway of the battery cell 10, and thus making the battery have higher reliability.

According to some embodiments of the present application, referring to FIG. 10 and FIG. 11 , the first wall 110 includes a main body portion 110 a and a first reinforcement portion 110 b connected to each other, and the first portion 130 is disposed on the first reinforcement portion 110 b .

In some embodiments, the first reinforcement portion 110b serves to strengthen the overall structural strength of the first wall 110 or to strengthen the local structural strength of the first wall 110, thereby increasing the impact resistance of the first wall 110 and reducing the risk of deformation of the first wall 110. In some embodiments, the first reinforcement portion 110b may be a reinforcing rib, a concave-convex structure, or the like.

In some embodiments, the first wall 110 includes a main body portion 110a and a first reinforcement portion 110b stacked on the surface of the main body portion 110a. The material of the first reinforcement portion 110b is the same as that of the main body portion 110a. The thickness of the first wall 110 is larger at the location of the first reinforcement portion 110b, so that this location has greater structural strength.

In some embodiments, the first wall 110 includes a main body portion 110 a , which is punched to form a convex portion on one side and a concave portion on the other side of the main body portion 110 a , and the portions where the convex portion and the concave portion are located form the first reinforcement portion 110 b .

In other embodiments, the first wall 110 includes a main body portion 110a and a first reinforcement portion 110b, the main body portion 110a is arranged around the edge of the first reinforcement portion 110b, the material of the first reinforcement portion 110b and the material of the main body portion 110a can be the same or different, and the structural strength of the first reinforcement portion 110b is greater than that of the main body portion 110a.

“The first portion 130 is disposed on the first reinforcement portion 110 b ” can be understood as that the portion of the first wall 110 used to support the first portion 130 is the portion of the first wall 110 with greater structural strength.

In the above scheme, by providing the first reinforcement portion 110b, the overall strength of the first wall 110 can be improved, and the risk of deformation of the first wall 110 due to internal pressure of the battery cell 10 or external impact, which causes the first deformable member 15 to be unable to effectively contact the first part 130 to conduct electricity between the first electrode terminal 13 and the first wall 110, can be reduced. The first deformable member 15 can effectively contact the first electrode terminal 13 under abuse conditions such as overcharging of the battery cell 10, thereby effectively playing the role of overcharge protection, reducing the risk of thermal runaway of the battery cell 10, and making the battery have higher reliability.

In some embodiments, the main body portion 110 a may be disposed around an edge of the first reinforcement portion 110 b .

In some embodiments, the first reinforcement portion 110b can be concave or convex relative to the main body portion 110a, such that the structural strength of the first reinforcement portion 110b is greater than that of the main body portion 110a. In other embodiments, the thickness of the first reinforcement portion 110b can be greater than that of the main body portion 110a, such that the structural strength of the first reinforcement portion 110b is greater than that of the main body portion 110a. By setting the structural strength of the first reinforcement portion 110b to be greater than that of the main body portion 110a, the overall strength of the first wall 110 can be effectively improved. Furthermore, the local portion of the first wall 110 corresponding to the first portion 130 can have greater structural strength, allowing the first portion 130 to effectively cooperate with the first deformable member 15, thereby improving the reliability of overcharge protection.

According to some embodiments of the present application, referring to FIG. 6 , the length of the first wall is greater than or equal to 150 mm, and the width of the first wall is greater than or equal to 45 mm.

In some embodiments, the battery cell 10 may be a square battery cell, and the first wall 110 may be an end cap of the outer shell 11. In order to make the battery cell 10 have a larger capacity, the volume of the outer shell 11 may be designed to be larger, and for this purpose, the size of the end cap is larger. In some embodiments, referring to FIG6 , the dimension of the end cap in its length direction is marked as C, that is, the value of the length C of the first wall 110 may be greater than or equal to 150 mm, for example, the value of C is 150 mm, 160 mm, 170 mm, 180 mm, a larger value, or any value between two adjacent values. The dimension of the end cap in its width direction is marked as D, that is, the value of the width D of the first wall 110 may be greater than or equal to 45 mm, for example, the value of D is 45 mm, 55 mm, 65 mm, 75 mm, a larger value, or any value between two adjacent values.

The length direction of the end cap may be the direction of the largest size of the end cap, the width direction of the end cap may be the direction of the smallest size, and the width direction of the end cap, the length direction of the end cap and the thickness direction of the end cap may be perpendicular to each other.

In the above scheme, by providing the first reinforcing portion 110b on the larger first wall 110, the structural strength lost due to the increase in the size of the first wall 110 can be effectively compensated, the overall strength of the first wall 110 can be improved, and the risk of deformation of the first wall 110 due to internal pressure of the battery cell 10 or external impact, which causes the first deformable member 15 to be unable to effectively contact the first portion 130 to conduct electricity between the first electrode terminal 13 and the first wall 110, can be reduced. The first deformable member 15 can effectively contact the first electrode terminal 13 under abuse conditions such as overcharging of the battery cell 10, thereby effectively playing the role of overcharge protection, reducing the risk of thermal runaway of the battery cell 10, and making the battery have higher reliability.

According to some embodiments of the present application, referring to FIG. 10 , the first reinforcement portion 110b includes a first protrusion 110b0 , which protrudes from a surface of the main body portion 110a along the thickness direction z of the first wall.

In some embodiments, the first reinforcement portion 110b includes a first protrusion 110b0 protruding from the surface of the first wall 110. For example, the first protrusion 110b0 protrudes from the outer side of the first wall 110; or the first protrusion 110b0 protrudes from the inner side of the first wall 110.

In some embodiments, the first wall 110 may include a main body 110a, which defines a first reinforcement region. The first protrusion 110b0 may be disposed in the first reinforcement region, and the portion where the first reinforcement region is located may be considered the first reinforcement portion 110b. The first portion 130 may be disposed in the first reinforcement region, for example, the first portion 130 may be disposed on a surface of the first protrusion 110b0 facing away from the main body 110a, or in a portion of the main body 110a facing away from the first protrusion 110b0. In some embodiments, the first protrusion 110b0 and the main body 110a may be separate structures, such as the first protrusion 110b0 being stacked on the main body 110a. The connection between the first protrusion 110b0 and the main body 110a includes, but is not limited to, bonding, welding, riveting, or screwing. In some embodiments, the first protrusion 110b0 and the main body 110a may be a unitary structure, formed integrally by stamping, casting, or other processes.

In the above solution, by providing the first protrusion 110b0 to strengthen the structural strength of the first wall 110, the risk of deformation of the first wall 110 due to internal pressure of the battery cell 10 or external impact, which causes the first deformable member 15 to be unable to effectively contact the first part 130 to conduct electricity between the first electrode terminal 13 and the first wall 110, can be effectively reduced, thereby making the battery have higher reliability.

According to some embodiments of the present application, referring to FIG. 11 , the first reinforcement portion 110b further includes a first recess 110b1 , which is disposed on another surface of the main body portion 110a along the thickness direction z of the first wall, and the first recess 110b1 is disposed opposite to the first protrusion 110b0 .

The first concave portion 110b1 corresponds to the first convex portion 110b0. For example, when the first convex portion 110b0 is located on the outside of the first wall 110, the first concave portion 110b1 is located on the inside of the first wall 110; conversely, when the first convex portion 110b0 is located on the inside of the first wall 110, the first concave portion 110b1 is located on the outside of the first wall 110.

In some embodiments, the first wall 110 may be formed by stamping to form the first convex portion 110b0 and the first concave portion 110b1. For example, along the thickness direction z of the first wall, a punch presses the first wall 110 from the inside to the outside of the first wall 110 to form the first convex portion 110b0 on the outside of the first wall 110 and the first concave portion 110b1 on the inside of the first wall 110.

In some embodiments of the present application, the first recess 110b1 is located on the inner side of the first wall 110, and at least part of the first deformable member 15 and the second portion 131 are located in the first recess 110b1.

In the above scheme, the first recess 110b1 is provided at a position corresponding to the first protrusion 110b0. On the one hand, the difficulty of forming the first protrusion 110b0 can be reduced and material costs can be saved. On the other hand, if the first recess 110b1 is located on the inner side of the first wall 110, the space of the first recess 110b1 can be used to accommodate more active substances or electrolytes, which is beneficial to the improvement of the energy density or charge and discharge performance of the battery cell 10, or the first deformable member 15 and the first electrode terminal 13 can utilize the space of the first recess 110b1 to reduce the occupation of the internal space of the battery cell 10; if the first recess 110b1 is located on the outer side of the first wall 110, the space of the first recess 110b1 can be used to accommodate external structural parts, which is beneficial to the improvement of the battery volume energy density.

According to some embodiments of the present application, referring to Figures 8 and 11 , the first protrusion 110b0 is located outside the first wall 110 and is formed with a first positioning groove 110b2 that receives the first portion 130 to restrict its movement.

In some embodiments, the first protrusion 110 b 0 is located on the outer side of the first wall 110 , and the first portion 130 may be disposed on the first protrusion 110 b 0 .

First positioning groove 110b2 is a groove structure formed in first protrusion 110b0, and first portion 130 is located in first positioning groove 110b2. For example, first protrusion 110b0 has a top surface facing away from electrode assembly 12. First positioning groove 110b2 is a square groove formed in this top surface. Square-shaped first portion 130 and a portion of first insulating portion 14 are located in first positioning groove 110b2. First insulating portion 14 is sandwiched between the groove wall of first positioning groove 110b2 and the outer peripheral surface of first portion 130.

In the above scheme, by setting the first positioning groove 110b2, the first electrode terminal 13 can be effectively positioned and the displacement of the first electrode terminal 13 can be limited. On the one hand, the risk of the first electrode terminal 13 being separated from the internal electrical connection component of the battery cell 10 and causing internal short circuit of the battery cell 10 is reduced. On the other hand, the first electrode terminal 13 can be effectively cooperated with the first deformable member 15 to play the role of overcharge protection and improve the reliability of the battery.

According to some embodiments of the present application, the first protrusion 110b0 is located outside the first wall 110, and along the thickness direction z of the first wall, the dimension of the first protrusion 110b0 protruding from the main body 110a is greater than or equal to 0.1 mm and less than or equal to 5 mm.

In some embodiments, referring to FIG. 11 , along the thickness direction z of the first wall, the first protrusion 110b0 protrudes from the main body 110a by a dimension L1, where L1 is greater than or equal to 0.1 mm and less than or equal to 5 mm. For example, L1 is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, ... 2.9 mm, 3 mm, 3.1 mm, 3.2 mm, 3.3 mm, ... 4.7 mm, 4.8 mm, 4.9 mm, 5 mm, or any value in between.

In the above solution, by setting the protrusion of the first protrusion 110b0 from the main body 110a to be greater than or equal to 0.1mm, the structural strength of the first wall 110 can be effectively improved, allowing the first deformable member 15 to effectively contact the first electrode terminal 13 when the internal pressure of the battery cell 10 reaches a certain level, such as the first threshold, thereby providing overcharge protection and thereby improving the reliability of the battery. By setting the protrusion of the first protrusion 110b0 from the main body 110a to be less than or equal to 5mm, the space occupied by the first protrusion 110b0 can be reduced, thereby reducing its impact on the battery's volumetric energy density. To this end, by setting the protrusion of the first protrusion 110b0 from the main body 110a to be greater than or equal to 0.1mm and less than or equal to 5mm, both the reliability of the battery cell 10's overcharge protection and the battery's volumetric energy density can be achieved.

According to some embodiments of the present application, along the thickness direction z of the first wall, a dimension of the first protrusion 110b0 protruding from the main body 110a is greater than or equal to 0.5 mm and less than or equal to 3 mm.

In some embodiments, along the thickness direction z of the first wall, the first protrusion 110b0 protrudes from the main body 110a by a dimension L1, where L1 is greater than or equal to 0.5 mm and less than or equal to 3 mm. For example, L1 is 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3 mm, or any value in between.

In the above solution, by setting the protrusion of the first protrusion 110b0 from the main body 110a to be greater than or equal to 0.5mm, the structural strength of the first wall 110 is further improved, allowing the first deformable member 15 to efficiently contact the first electrode terminal 13 when the internal pressure of the battery cell 10 reaches the first threshold, thereby providing overcharge protection and improving the reliability of the battery. By setting the protrusion of the first protrusion 110b0 from the main body 110a to be less than or equal to 3mm, the space occupied by the first protrusion 110b0 can be effectively reduced, thereby reducing its impact on the battery's volumetric energy density. To this end, by setting the protrusion of the first protrusion 110b0 from the main body 110a to be greater than or equal to 0.5mm and less than or equal to 3mm, both the reliability of the battery cell 10's overcharge protection and the battery's volumetric energy density can be achieved.

According to some embodiments of the present application, referring to Figures 5, 7 and 8, the first insulating portion 14 includes a first insulating member 140, at least a portion of the first insulating member 140 is arranged between the first portion 130 of the first electrode terminal 13 located on the outside of the first wall 110 and the first wall 110, and the first insulating member 140 is formed with a third through hole 14001 and a fourth through hole 14002. Along the thickness direction z of the first wall, the third through hole 14001 is arranged opposite to the first through hole 1100, and the fourth through hole 14002 is arranged opposite to the second through hole 1101.

In some embodiments, referring to FIG5 , the first insulating member 140 can be considered plate-shaped and is disposed between the first portion 130 and the first wall 110 to insulate and isolate the first portion 130 from the first wall 110. The first insulating member 140 has a third through hole 14001 and a fourth through hole 14002 extending through the first wall along the thickness direction z. The third through hole 14001 is provided corresponding to the first through hole 1100 for the first electrode terminal 13 to pass through. The fourth through hole 14002 is provided corresponding to the second through hole 1101 for the first deformable member 15 to pass through after deformation to contact the first portion 130.

In some embodiments, the third through hole 14001 may be a square hole, a circular hole, or other shapes. The fourth through hole 14002 may be a square hole, a circular hole, or other shapes.

In some embodiments, the third through hole 14001 and the first through hole 1100 may be circular holes, and the diameter of the third through hole 14001 may be smaller than or equal to the diameter of the first through hole 1100. In some embodiments, the fourth through hole 14002 and the second through hole 1101 may be circular holes, and the diameter of the fourth through hole 14002 may be smaller than or equal to the diameter of the second through hole 1101.

For example, in some embodiments of the present application, the material of the first insulating member 140 may include insulating PPS (polyphenylene sulfide). In other embodiments, the first insulating member 140 may also be made of other insulating materials such as polypropylene and polyethylene. For example, in some embodiments of the present application, the resistance of the first insulating member 140 in the battery cell 10 may be greater than or equal to 200 MΩ.

In the above scheme, the first insulating member 140 has a simple structure. On the one hand, the first electrode terminal 13 is allowed to pass through the third through hole 14001, so that the first electrode terminal 13 is electrically connected to the electrode assembly 12 and external charging and discharging is realized. The first deformable member 15 is allowed to deform through the fourth through hole 14002 so as to be able to contact the first part 130 to achieve overcharge protection; on the other hand, the first insulating member 140 can effectively insulate and isolate the first part 130 and the first wall 110, reducing the risk of internal short circuit of the battery cell 10 due to short circuit between the first part 130 and the first wall 110, thereby making the battery highly reliable.

According to some embodiments of the present application, referring to FIG8 , the first insulating member 140 includes a first body 1400 and a first flange 1401 , the first body 1400 is located between the first portion 130 and the first wall 110 , the first flange 1401 is arranged on a surface of the first body 1400 facing away from the first wall 110 , and the first flange 1401 surrounds at least a portion of the outer peripheral surface of the first portion 130 .

In some embodiments, the first body 1400 is sandwiched between the first portion 130 and the first wall 110 , and the first body 1400 is flat in shape. The first flange 1401 is protruded from the surface of the first body 1400 and surrounds the outer circumference of the first portion 130 .

“The first flange 1401 surrounds at least a portion of the outer circumference of the first part 130 ” can be understood as the first flange 1401 being able to completely cover the outer circumference of the first part 130 or the first flange 1401 being able to partially cover the outer circumference of the first part 130 .

In some embodiments, referring to FIG. 8 , the first insulating member 140 wraps the first portion 130 and is located in the first positioning groove 110 b 2 , and the first flange 1401 is located between the outer circumference of the first portion 130 and the groove wall of the first positioning groove 110 b 2 .

In the above scheme, by setting the first body 1400 and the first flange 1401, the first wall 110 and the first part 130 can be effectively insulated and isolated, so that there is a longer creepage distance between the first part 130 and the first wall 110, and the first insulating member 140 has higher insulation performance, effectively reducing the risk of internal short circuit of the battery cell 10 due to short circuit between the first wall 110 and the first electrode terminal 13, so that the reliability of the battery is high.

According to some embodiments of the present application, referring to FIG. 8 , the first insulating member 140 further includes a second flange 1402 . The second flange 1402 is disposed around the third through hole 14001 and is located between the hole wall of the first through hole 1100 and the first electrode terminal 13 .

The second flange 1402 is part of the first insulating member 140. The second flange 1402 is connected to the first body 1400 and disposed around the third through-hole 14001. Along the thickness direction z of the first wall, the second flange 1402 protrudes toward the first through-hole 1100 to cover a portion of the wall of the first through-hole 1100, thereby insulating and isolating the first electrode terminal 13 from the wall of the first through-hole 1100. In some embodiments, the second flange 1402 also serves as a positioning mechanism. By aligning the second flange 1402 with the first through-hole 1100, the first insulating member 140 can be quickly assembled to the first wall 110.

In some embodiments, the second flange 1402 may partially or completely cover the hole wall of the first through hole 1100 .

In the above solution, by providing the second flange 1402, the hole wall of the first through hole 1100 and the first electrode terminal 13 can be effectively insulated and isolated, reducing the risk of the first electrode terminal 13 contacting the hole wall of the first through hole 1100 and causing an internal short circuit in the battery cell 10, thereby effectively improving the reliability of the battery.

In some embodiments, referring to Figures 5 and 8, the first insulating portion 14 may further include a first sealing portion 141. The first sealing portion 141 may be sleeved on the second portion 131, and a portion of the first sealing portion 141 may be clamped between the first through hole 1100 and the second portion 131. Another portion of the first sealing portion 141 may be clamped between the surface of the first wall 110 facing away from the first portion 130 and the second portion 131.

According to some embodiments of the present application, please refer to Figures 4 to 13. Figure 12 is a schematic diagram of the first wall and the second electrode terminal in some embodiments of the present application, and Figure 13 is a schematic diagram of the second deformation member 18 in some embodiments of the present application.

The battery cell 10 also includes a second electrode terminal 16, a second insulating portion 17, and a second deformable member 18. The second electrode terminal 16 is disposed on the first wall 110 and electrically connected to the electrode assembly 12. The second electrode terminal 16 is used for inputting and outputting electrical energy, and the polarity of the second electrode terminal 16 and the first electrode terminal 13 are opposite. The second insulating portion 17 is disposed between the first wall 110 and the second electrode terminal 16 to insulate and isolate the second electrode terminal 16 from the first wall 110. The second deformable member 18 is electrically connected to the first wall 110 and is configured to deform into contact with the second electrode terminal 16 to electrically connect the second electrode terminal 16 to the first wall 110.

The second electrode terminal 16 is a component mounted on the first wall 110. The second electrode terminal 16 is used to electrically connect to the electrode assembly 12, allowing current to flow into or out of the second electrode tab 121 through the second electrode terminal 16. The second electrode terminal 16 and the second electrode tab 121 have the same polarity. In some embodiments, when the first electrode terminal 13 is a positive electrode terminal, the second electrode terminal 16 is a negative electrode terminal. When the first electrode terminal 13 is a negative electrode terminal, the second electrode terminal 16 is a positive electrode terminal.

In some embodiments, the second electrode terminal 16 is made of a metal material, such as aluminum, copper, iron, aluminum, steel, an alloy, or a composite metal. In some embodiments, the second electrode terminal 16 can be connected to the second electrode tab 121 via a second adapter 124. For example, the second electrode tab 121 of the electrode assembly 12 is composed of a plurality of second sub-electrode tabs stacked together. After welding one end of the second adapter 124 to the second electrode tab 121, the other end of the second adapter 124 can be welded to the second electrode terminal 16.

The second insulating portion 17 has a high resistance, insulating the second electrode terminal 16 from the first wall 110. For example, referring to FIG. 5 , the second electrode terminal 16 has an exposed third portion 160. The second insulating portion 17 can be disposed between the outer side of the first wall 110 and the third portion 160 to insulate the second electrode terminal 16 from the first wall 110. In some embodiments, the second insulating portion 17 can cover the outer periphery of the third portion 160 to increase the creepage distance between the second electrode terminal 16 and the first wall 110.

For example, in some embodiments, a fifth through-hole 1102 is formed in the first wall 110. The second electrode terminal 16 can pass through the fifth through-hole 1102 to form a third portion 160 on the outside and a fourth portion 161 on the inside. The third portion 160 is used to connect to an external electrical connection member, and the fourth portion 161 is used to electrically connect to the electrode assembly 12. The second insulating portion 17 has a seventh through-hole 17001 formed therein, corresponding to the fifth through-hole 1102, for the second electrode terminal 16 to pass through. Alternatively, a major portion of the second insulating portion 17 is located between the third portion 160 and the first wall 110, while some portion of the second insulating portion 17 may be located between the fifth through-hole 1102 and the second electrode terminal 16. Alternatively, a major portion of the second insulating portion 17 is located between the third portion 160 and the first wall 110, while some portion of the second insulating portion 17 may be located between the fifth through-hole 1102 and the second electrode terminal 16, and the remaining portion of the second insulating portion 17 may also be located between the first wall 110 and the fourth portion 161.

In some embodiments, the second insulating portion 17 may be in a plate shape as a whole, and its two opposite surfaces are relatively flat so as to be stably positioned between the second electrode terminal 16 and the first wall 110 .

In some embodiments, the second insulating portion 17 can be made of a material with a relatively high resistance, such as an organic insulating material, an inorganic insulating material, or a mixed insulating material. For example, in some embodiments of the present application, the material of the second insulating portion 17 can include an insulating PPS (polyphenylene sulfide) material. In other embodiments, the second insulating portion 17 can also be made of other materials with insulating properties, such as polypropylene and polyethylene.

In some embodiments, the resistance value of the second insulating portion 17 can be measured in megohms (MΩ). For example, in the battery cell 10 provided in some embodiments of the present application, the resistance value of the second insulating portion 17 can be greater than or equal to 200 MΩ. In other embodiments, the resistance value of the second insulating portion 17 can be other values, such as 1 MΩ, 10 MΩ, 20 MΩ, 30 MΩ, 40 MΩ, 50 MΩ, 60 MΩ, 70 MΩ, 80 MΩ, 90 MΩ, 100 MΩ, 110 MΩ, 120 MΩ, 130 MΩ…210 MΩ, 220 MΩ, 230 MΩ, etc.

The second deformable member 18 is mounted on the first wall 110 and is electrically connected to the first wall 110. In some embodiments, the second deformable member 18 can be made of a metal material, such as aluminum, copper, iron, aluminum, steel, an alloy, or a composite metal. In some embodiments, the second deformable member 18 can be welded to the inner side of the first wall 110.

The second deformable member 18 is a structural member that deforms due to the internal pressure of the battery cell 10. The second deformable member 18 is used to protect the battery cell 10 from overcharge. For example, when the battery cell 10 is subjected to an abusive operating condition such as overcharge, the internal pressure increases. When the internal pressure reaches a certain level, such as a second threshold, the second deformable member 18 deforms to contact the second electrode terminal 16, thereby electrically connecting the first wall 110 to the second electrode terminal 16, short-circuiting the positive and negative electrodes within the battery cell 10.

In some embodiments, the portion of the second deformable member 18 that is deformed by pressure to contact the second electrode terminal 16 can be the inner portion of the second electrode terminal 16 on the first wall 110, or the portion of the second electrode terminal 16 on the outer side of the first wall 110. For example, the second deformable member 18 can be deformed and connected to the fourth portion 161 when the internal pressure of the battery cell 10 reaches the second threshold value. For another example, the second deformable member 18 can be deformed and connected to the third portion 160 when the internal pressure of the battery cell 10 reaches the second threshold value.

In some embodiments, the second deformable member 18 may be a flip sheet that flips under pressure. For example, referring to Figures 5 and 13 , the second deformable member 18 has a disc-shaped outer profile and comprises, from the outside inward, a second skirt 180, a second flip foil 181, and a second electrical connection portion 182. The second skirt 180 may be connected to the first wall 110. The second flip foil 181 is relatively thin and is designed to deform and flip under pressure. After the second flip foil 181 flips, it can push the second electrical connection portion 182 toward the second electrode terminal 16, thereby bringing the second electrical connection portion 182 into contact with the second electrode terminal 16.

Illustratively, the first wall 110 has a sixth through hole 1103, and the second skirt 180 is welded to the first wall 110, so that the second deformable member 18 closes the sixth through hole 1103. In its natural state, the second flip foil 181 is collapsed away from the first wall 110. When the internal pressure of the battery cell 10 reaches a second threshold, the second flip foil 181 flips toward the first wall 110 to push the second electrical connection portion 182, thereby allowing the second electrical connection portion 182 to pass through the sixth through hole 1103 and contact the third portion 160.

In some embodiments, when a battery cell 10 is subjected to abuse due to overcharging or other conditions, the internal pressure of the battery cell 10 increases. When the internal pressure of the battery cell 10 reaches a certain level, such as a first threshold, the first deformable member 15 deforms, short-circuiting the first electrode terminal 13 and the outer casing 11. When the internal pressure of the battery cell 10 reaches a second threshold, the second deformable member 18 deforms, short-circuiting the second electrode terminal 16 and the outer casing 11, thereby short-circuiting the positive and negative electrodes within the battery cell 10 and creating an internal short circuit. The resulting high current can melt the electrical connections within the battery cell 10, severing the charge and discharge circuit of the battery cell 10, thereby providing overcharge protection. The fused electrical connections can include the first adapter 123 and/or the second adapter 124. For example, the first adapter 123 has a first fuse portion, the flow area of which can be smaller than the flow area of the remaining portions of the first adapter 123. This allows the first fuse portion to melt when a large current flows, thereby severing the current path between the first tab 120 and the first electrode terminal 13. Exemplarily, the second adapter 124 has a second fuse portion, and the flow area of the second fuse portion can be smaller than the flow area of the rest of the second adapter 124, so that when a larger current passes through, the second fuse portion can be melted, thereby disconnecting the current path between the second electrode tab 121 and the second electrode terminal 16.

In the above solution, on the one hand, by providing the second insulating portion 17 between the first wall 110 and the second electrode terminal 16, the first wall 110 and the second electrode terminal 16 can be effectively insulated and isolated, thereby reducing the risk of internal short circuit of the battery cell 10 due to short circuit between the first wall 110 and the second electrode terminal 16, thereby improving the reliability of the battery; on the other hand, by providing the second deformable member 18, when the internal pressure of the battery cell 10 reaches a certain level, such as the second threshold value, the second deformable member 18 is deformed to contact the second electrode terminal 16, thereby electrically connecting the second electrode terminal 16 to the second wall, and cooperating with the short circuit of the first deformable member 15 and the first electrode terminal 13, the internal pressure of the battery cell 10 is reduced. The electrical connection component is melted due to the large current generated by the short circuit, so as to cut off the charge and discharge circuit of the battery cell 10, thereby playing the role of overcharge protection and reducing the risk of thermal runaway of the battery cell 10, thereby making the battery have higher reliability; on the other hand, because the first electrode terminal 13 and the second electrode terminal 16 are insulated and isolated from the first wall 110 under non-abuse conditions, the shell 11 of the battery cell 10 can be uncharged, so that the battery cell 10 constitutes an energy storage device, which reduces the risk of ignition and breakdown between two adjacent battery cells 10 in the energy storage device. At the same time, by providing the second deformable member 18, the overcharge protection function can be effectively achieved, so that the energy storage device has high reliability.

According to some embodiments of the present application, the second electrode terminal 16 is a negative electrode terminal, so that the minimum pressure value for deforming the second deformable member 18 is greater than the minimum pressure value for deforming the first deformable member 15 .

In some embodiments, when the internal pressure of the battery cell 10 reaches a first threshold, the first deforming member 15 deforms. When the internal pressure of the battery cell 10 reaches a second threshold, the second deforming member deforms. The second threshold may be greater than the first threshold.

In some embodiments, the second electrode terminal 16 is a negative electrode terminal, that is, the second electrode terminal 16 is electrically connected to the negative electrode tab of the electrode assembly 12 .

“The second threshold is greater than the first threshold” can be understood as the second deformable member 18 is less susceptible to deformation than the first deformable member 15 , that is, the second deformable member 18 deforms only when the internal pressure of the battery cell 10 further increases and exceeds the first threshold.

In some embodiments, the manufacturing material or structure of the second deformable member 18 can be modified to make the second deformable member 18 less susceptible to deformation than the first deformable member 15. For example, in some embodiments, the thickness of the second flip foil 181 of the second deformable member 18 is greater than the thickness of the first flip foil 151 of the first deformable member 15, so that the second deformable member 18 deforms to contact the second electrode terminal 16 only when subjected to greater pressure. Alternatively, in some embodiments, a reinforcing structure, such as a reinforcing rib or a reinforcing concave-convex portion, is provided on the second flip foil 181, so that the second deformable member 18 deforms to contact the second electrode terminal 16 only when subjected to greater pressure.

In some embodiments, "the second threshold is greater than the first threshold" can be understood to mean that the second deformable member 18 requires a greater pressure than the first deformable member 15 to contact the second electrode terminal 16. In other words, the second deformable member 18 only contacts the second electrode terminal 16 when the internal pressure of the battery cell 10 further increases and exceeds the first threshold. For example, the distance between the second deformable member 18 and the second electrode terminal 16 can be increased so that the second deformable member 18 requires a greater amount of deformation to contact the second electrode terminal 16. For example, the distance between the second electrical connection portion 182 and the second electrode terminal 16 is greater than the distance between the first electrical connection portion 152 and the first electrode terminal 13; for another example, in a natural state, the second flip foil 181 is further away from the first wall 110 than the first flip foil 151.

In the above scheme, when the second electrode terminal 16 is a negative electrode terminal, by setting the second threshold value to be greater than the first threshold value, the second deformable member 18 can be deformed when the pressure inside the battery cell 10 is greater than that of the first deformable member 15. On the one hand, the battery cell 10 can have an overcharge protection function. On the other hand, it can reduce the risk of gas production inside the battery cell 10 causing the second deformable member 18 to flip over, resulting in the outer shell 11 being negatively charged and corroded by the electrolyte under non-overcharge abuse conditions, thereby ensuring the integrity of the outer shell 11 to a certain extent, reducing the risk of electrolyte leakage, and thus improving the reliability of the battery.

"It can reduce the risk of gas production inside the battery cell 10 causing the second deformable member 18 to flip over, resulting in the shell 11 being negatively charged and corroded by the electrolyte under non-overcharge abuse conditions" can be understood as follows: as the number of charge and discharge times of the battery cell 10 increases, the gas production inside the battery cell 10 also increases. At the end of the life of the battery cell 10, the internal gas is high, resulting in high internal pressure. At this time, the battery is not in an overcharged state, but its internal pressure is too high, which may cause the second deformable member 18 to deform to connect the negative ear of the electrode assembly 12 and the shell 11, making the shell 11 negatively charged. However, the negative charge of the shell 11 will cause an electrochemical reaction with the electrolyte, causing the shell 11 to be corroded, and there is a risk of leakage. To this end, by setting the second threshold value larger than the first threshold value, the probability of the shell 11 being negatively charged due to non-overcharge and other conditions can be reduced, thereby improving the integrity of the shell 11 and improving the reliability of the battery.

In some other embodiments, the magnitude relationship between the first threshold and the second threshold is not limited. For example, the first threshold may be equal to the second threshold.

According to some embodiments of the present application, please refer to Figures 10, 12, and 14. Figure 14 is a partial schematic diagram of the first wall 110 in some embodiments of the present application. The first wall 110 is formed with a fifth through-hole 1102 and a sixth through-hole 1103. The second electrode terminal 16 passes through the fifth through-hole 1102. Along the thickness direction z of the first wall, the second deformable member 18 closes the sixth through-hole 1103. The second deformable member 18 is configured to deform to partially pass through the sixth through-hole 1103 and contact the second electrode terminal 16.

In some embodiments, the first wall 110 may be an end cap of the housing 11 and may be plate-shaped. A fifth through-hole 1102 and a sixth through-hole 1103 are formed along the thickness direction z of the first wall 110. The fifth through-hole 1102 allows the second electrode terminal 16 to pass through, while the sixth through-hole 1103 allows the second deformable member 18 to pass through.

For example, referring to FIG. 12 , the second electrode terminal 16 includes a third portion 160 and a fourth portion 161. The third portion 160 is located outside the first wall 110 and can be flat for electrical connection to external structures. A portion of the fourth portion 161 is located inside the first wall 110 for electrical connection to the electrode assembly 12. Another portion of the fourth portion 161 is connected to the third portion 160 through a fifth through-hole 1102. Connections between the fourth portion 161 and the third portion 160 include, but are not limited to, welding, bonding, riveting, or screwing. In other embodiments, the third portion 160 can be partially located outside the first wall 110, with another portion of the third portion 160 connected to the fourth portion 161 through the fifth through-hole 1102. In other embodiments, the third portion 160 can be partially located outside the first wall 110, while a portion of the fourth portion 161 is located inside the first wall 110. Another portion of the third portion 160 and another portion of the fourth portion 161 are located within the fifth through-hole 1102 and connected to each other.

"Second deformable member 18 closes sixth through hole 1103" may mean that second deformable member 18 closes sixth through hole 1103, thereby enclosing electrode assembly 12 and electrolyte. In some embodiments, second skirt 180 of second deformable member 18 is disposed around the edge of sixth through hole 1103 and welded to the inner side of first wall 110.

In some embodiments, when the internal pressure of the battery cell 10 reaches a certain level, such as a second threshold, the second deformation member 18 can be deformed toward the third portion 160 to pass through the sixth through hole 1103 and contact the third portion 160 .

In some embodiments, the sixth through hole 1103 can be a stepped hole shape, which can provide a connection portion for the second skirt 180 of the second deformable member 18, so that the second skirt 180 can be accommodated in the sixth through hole 1103, reducing the occupation of the internal space of the battery cell 10 by the second deformable member 18.

In the above scheme, when the internal pressure of the battery cell 10 reaches a certain level, such as the second threshold value, the internal pressure of the battery cell 10 can act on the second deformable member 18, so that the second deformable member 18 is deformed toward the outside of the first wall 110 to effectively contact the third part 160 of the second electrode terminal 16, and cooperates with the first deformable member 15 to contact the first electrode terminal 13, so that the electrical connection components inside the battery cell 10 are melted due to the large current generated by the short circuit, so as to cut off the charging and discharging circuit of the battery cell 10, thereby reducing the risk of thermal runaway of the battery cell 10, and thus making the battery have higher reliability.

According to some embodiments of the present application, referring to FIG. 12 , along the thickness direction z of the first wall, the projection of the third portion 160 of the second electrode terminal 16 located outside the first wall 110 at least partially overlaps with the projection of the second deformable member 18 .

In some embodiments, the third part 160 is larger in size, and along the thickness direction z of the first wall, a portion of the third part 160 can be set opposite the fourth part 161 to be connected to the fourth part 161, and a portion of the third part 160 can be opposite the second deforming member 18 to directly contact the second deforming member 18 when the second deforming member 18 is deformed.

In some embodiments, along the thickness direction z of the first wall, the projection of the second deformable member 18 may entirely fall on the third portion 160. In other embodiments, along the thickness direction z of the first wall, the projection of the second deformable member 18 may partially fall on the third portion 160, while another portion may be offset from the third portion 160.

In the above scheme, by arranging the second deformable member 18 along the thickness direction z of the first wall corresponding to the third part 160, when the pressure inside the battery cell 10 reaches a certain level, such as the second threshold, the third part 160 can be quickly contacted with a smaller deformation amount, thereby quickly electrically connecting the second electrode terminal 16 and the first wall 110, and cooperating with the first deformable member 15 to contact the first electrode terminal 13, so that the electrical connection components inside the battery cell 10 are melted due to the large current generated by the short circuit, thereby cutting off the charge and discharge circuit of the battery cell 10, thereby reducing the risk of thermal runaway of the battery cell 10, and thus making the battery have higher reliability.

According to some embodiments of the present application, referring to FIG. 10 , the first wall 110 includes a main body portion 110 a and a second reinforcement portion 110 c connected to each other, and the third portion 160 of the second electrode terminal 16 located outside the first wall 110 is disposed on the second reinforcement portion 110 c.

In some embodiments, the second reinforcement portion 110c is used to strengthen the overall structural strength of the first wall 110 or to strengthen the local structural strength of the first wall 110, thereby enhancing the impact resistance of the first wall 110 and reducing the risk of deformation of the first wall 110. In some embodiments, the second reinforcement portion 110c may be a reinforcing rib, a concave-convex structure, or the like.

In some embodiments, the first wall 110 includes a main body portion 110a and a second reinforcement portion 110c stacked on the surface of the main body portion 110a. The material of the second reinforcement portion 110c is the same as that of the main body portion 110a. The thickness of the first wall 110 is larger at the location of the second reinforcement portion 110c, so that this portion has greater structural strength.

In some embodiments, the first wall 110 includes a main body portion 110 a , which is punched to form a convex portion on one side and a concave portion on the other side of the main body portion 110 a , and the portions where the convex portion and the concave portion are located form the second reinforcement portion 110 c .

In other embodiments, the first wall 110 includes a main body portion 110a and a second reinforcement portion 110c, the main body portion 110a is arranged around the edge of the second reinforcement portion 110c, the material of the second reinforcement portion 110c and the material of the main body portion 110a can be the same or different, and the structural strength of the second reinforcement portion 110c is greater than that of the main body portion 110a.

“The third portion 160 is disposed on the second reinforcement portion 110 c ” can be understood as that the portion of the first wall 110 used to support the third portion 160 is the portion of the first wall 110 with greater structural strength.

In the above scheme, by providing the second reinforcement portion 110c, the overall strength of the first wall 110 can be improved, and the risk of deformation of the first wall 110 due to internal pressure of the battery cell 10 or external impact, which causes the second deformable member 18 to be unable to effectively contact the third part 160 to conduct electricity between the second electrode terminal 16 and the first wall 110, can be reduced. The second deformable member 18 can effectively contact the second electrode terminal 16 under abuse conditions such as overcharging of the battery cell 10, thereby effectively playing the role of overcharge protection, reducing the risk of thermal runaway of the battery cell 10, and making the battery have higher reliability.

In some embodiments, the second reinforcement portion 110 c is less susceptible to deformation than the main body portion 110 a , thereby being able to provide effective support for the third portion 160 .

In some embodiments, the main body portion 110 a may be disposed around an edge of the second reinforcement portion 110 c .

In some embodiments, the second reinforcement portion 110c can be concave or convex relative to the main body portion 110a, such that the structural strength of the second reinforcement portion 110c is greater than that of the main body portion 110a. In other embodiments, the thickness of the second reinforcement portion 110c can be greater than that of the main body portion 110a, such that the structural strength of the second reinforcement portion 110c is greater than that of the main body portion 110a. By setting the structural strength of the second reinforcement portion 110c to be greater than that of the main body portion 110a, the overall strength of the first wall 110 can be effectively improved. Furthermore, the local portion of the first wall 110 corresponding to the third portion 160 can have greater structural strength, allowing the third portion 160 to effectively cooperate with the second deformable member 18, thereby improving the reliability of overcharge protection.

According to some embodiments of the present application, referring to FIG. 10 and FIG. 14 , the second reinforcing portion 110 c includes a second protrusion 110 c 0 , which protrudes from a surface of the main body 110 a along the thickness direction z of the first wall.

In some embodiments, the second reinforcement portion 110c includes a second protrusion 110c0 protruding from the surface of the first wall 110. For example, the second protrusion 110c0 protrudes from the outer side of the first wall 110; or the first protrusion 110b0 protrudes from the inner side of the first wall 110.

In some embodiments, the first wall 110 may include a main body 110a, which defines a second reinforcement region. The second protrusion 110c0 may be disposed in the second reinforcement region, and the portion where the second reinforcement region is located may be considered the second reinforcement portion 110c. The third portion 160 may be disposed in the second reinforcement region. For example, the third portion 160 may be disposed on a surface of the second protrusion 110c0 facing away from the main body 110a, or in a portion of the main body 110a facing away from the second protrusion 110c0. In some embodiments, the second protrusion 110c0 and the main body 110a may be separate structures, such as being stacked on the main body 110a. The connection between the second protrusion 110c0 and the main body 110a includes, but is not limited to, bonding, welding, riveting, or screwing. In some embodiments, the second protrusion 110c0 and the main body 110a may be an integral structure, formed integrally by stamping, casting, or other processes.

In the above solution, by providing the second protrusion 110c0 to strengthen the structural strength of the first wall 110, the risk of deformation of the first wall 110 due to internal pressure of the battery cell 10 or external impact, which causes the second deformable member 18 to be unable to effectively contact the third part 160 to conduct electricity between the second electrode terminal 16 and the first wall 110, can be effectively reduced, thereby making the battery have higher reliability.

According to some embodiments of the present application, the second reinforcement portion 110c further includes a second recess 110c1, which is arranged on another surface of the main body portion 110a along the thickness direction z of the first wall, and the second recess 110c1 is arranged opposite to the second protrusion 110c0.

The second concave portion 110c1 corresponds to the second convex portion 110c0. For example, when the second convex portion 110c0 is located on the outside of the first wall 110, the second concave portion 110c1 is located on the inside of the first wall 110; conversely, when the second convex portion 110c0 is located on the inside of the first wall 110, the second concave portion 110c1 is located on the outside of the first wall 110.

In some embodiments, the first wall 110 may be formed by stamping to form the second convex portion 110c0 and the second concave portion 110c1. For example, along the thickness direction z of the first wall, a punch presses the first wall 110 from the inside to the outside of the first wall 110 to form the second convex portion 110c0 on the outside of the first wall 110 and the second concave portion 110c1 on the inside of the first wall 110.

In some embodiments of the present application, the second recess 110c1 is located on the inner side of the first wall 110 , and at least part of the second deformable member 18 and the fourth portion 161 is located in the second recess 110c1 .

In the above solution, the second recess 110c1 is provided at a position corresponding to the second protrusion 110c0. On the one hand, the difficulty of forming the second protrusion 110c0 can be reduced and material costs can be saved. On the other hand, if the second recess 110c1 is located on the inner side of the first wall 110, the space of the second recess 110c1 can be used to accommodate more active substances or electrolytes, which is beneficial to the improvement of the energy density or charge and discharge performance of the battery cell 10. If the second recess 110c1 is located on the outer side of the first wall 110, the space of the second recess 110c1 can be used to accommodate external structural parts, which is beneficial to the improvement of the battery volume energy density.

According to some embodiments of the present application, referring to FIG. 12 and FIG. 14 , the second protrusion 110c0 is located on the outside of the first wall 110 , and the second protrusion 110c0 is formed with a second positioning groove 110c2 , which accommodates the third portion 160 to limit the movement of the third portion 160 .

In some embodiments, the second protrusion 110 c 0 is located on the outer side of the first wall 110 , and the third portion 160 may be disposed on the second protrusion 110 c 0 .

Second positioning groove 110c2 is a groove structure formed in second protrusion 110c0, and third portion 160 is located in second positioning groove 110c2. Exemplarily, second protrusion 110c0 has a top surface facing away from electrode assembly 12. Second positioning groove 110c2 is a square groove formed in this top surface. The square-shaped third portion 160 and a portion of second insulating portion 17 are located in second positioning groove 110c2. Second insulating portion 17 is sandwiched between the groove wall of second positioning groove 110c2 and the outer peripheral surface of third portion 160.

In the above scheme, by providing the second positioning groove 110c2, the second electrode terminal 16 can be effectively positioned and the displacement of the second electrode terminal 16 can be limited. On the one hand, the risk of the second electrode terminal 16 being separated from the internal electrical connection component of the battery cell 10 and causing internal short circuit of the battery cell 10 is reduced. On the other hand, the second electrode terminal 16 can be effectively matched with the second deformable member 18 to play the role of overcharge protection and improve the reliability of the battery.

According to some embodiments of the present application, the second protrusion 110c0 is located outside the first wall 110, and along the thickness direction z of the first wall, the dimension of the second protrusion 110c0 protruding from the main body 110a is greater than or equal to 0.1 mm and less than or equal to 5 mm.

In some embodiments, referring to FIG. 14 , along the thickness direction z of the first wall, the second protrusion 110c0 protrudes from the main body 110a by a dimension L2, where L2 is greater than or equal to 0.1 mm and less than or equal to 5 mm. For example, L2 is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, ... 2.9 mm, 3 mm, 3.1 mm, 3.2 mm, 3.3 mm, ... 4.7 mm, 4.8 mm, 4.9 mm, 5 mm, or any value in between.

In the above solution, by setting the protrusion of the second protrusion 110c0 from the main body 110a to be greater than or equal to 0.1 mm, the structural strength of the first wall 110 can be effectively improved, allowing the second deformable member 18 to effectively contact the second electrode terminal 16 when the internal pressure of the battery cell 10 reaches the second threshold, thereby providing overcharge protection and improving the reliability of the battery. By setting the protrusion of the second protrusion 110c0 from the main body 110a to be less than or equal to 5 mm, the space occupied by the second protrusion 110c0 can be reduced, thereby reducing the impact on the battery's volumetric energy density. To this end, by setting the protrusion of the second protrusion 110c0 from the main body 110a to be greater than or equal to 0.1 mm and less than or equal to 5 mm, both the reliability of the overcharge protection of the battery cell 10 and the volumetric energy density of the battery can be achieved.

According to some embodiments of the present application, along the thickness direction z of the first wall, a dimension of the second protrusion 110c0 protruding from the main body 110a is greater than or equal to 0.5 mm and less than or equal to 3 mm.

In some embodiments, along the thickness direction z of the first wall, the second protrusion 110c0 protrudes from the main body 110a by a dimension L2, where L2 is greater than or equal to 0.5 mm and less than or equal to 3 mm. For example, L2 is 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3 mm, or any value in between.

In the above solution, by setting the protrusion of the second protrusion 110c0 from the main body 110a to be greater than or equal to 0.5mm, the structural strength of the first wall 110 is further improved, allowing the second deformable member 18 to effectively contact the second electrode terminal 16 when the internal pressure of the battery cell 10 reaches the second threshold, thereby providing overcharge protection and improving the reliability of the battery. By setting the protrusion of the second protrusion 110c0 from the main body 110a to be less than or equal to 3mm, the space occupied by the second protrusion 110c0 can be effectively reduced, thereby reducing the impact on the battery's volumetric energy density. To this end, by setting the protrusion of the second protrusion 110c0 from the main body 110a to be greater than or equal to 0.5mm and less than or equal to 3mm, the reliability of the overcharge protection of the battery cell 10 and the volumetric energy density of the battery can be balanced.

According to some embodiments of the present application, referring to Figures 5, 7 and 11, the second insulating portion 17 includes a second insulating member 170, at least a portion of the second insulating member 170 is arranged between the third portion 160 and the first wall 110, and the second insulating member 170 is formed with a seventh through hole 17001 and an eighth through hole 17002. Along the thickness direction z of the first wall, the seventh through hole 17001 is arranged opposite to the fifth through hole 1102, and the eighth through hole 17002 is arranged opposite to the sixth through hole 1103.

In some embodiments, referring to FIG5 , the second insulating member 170 can be considered plate-shaped and is disposed between the third portion 160 and the first wall 110 to insulate and isolate the third portion 160 from the first wall 110. The second insulating member 170 has a seventh through hole 17001 and an eighth through hole 17002 extending through the first wall along the thickness direction z. The seventh through hole 17001 is provided corresponding to the fifth through hole 1102 for allowing the second electrode terminal 16 to pass through. The eighth through hole 17002 is provided corresponding to the sixth through hole 1103 for allowing the second deformable member 18 to pass through after deformation to contact the third portion 160.

In some embodiments, the seventh through hole 17001 may be a square hole, a circular hole, or other shapes. The eighth through hole 17002 may be a square hole, a circular hole, or other shapes.

In some embodiments, the seventh through hole 17001 and the fifth through hole 1102 may be circular holes, and the diameter of the seventh through hole 17001 may be smaller than or equal to the diameter of the fifth through hole 1102. In some embodiments, the eighth through hole 17002 and the sixth through hole 1103 may be circular holes, and the diameter of the eighth through hole 17002 may be smaller than or equal to the diameter of the sixth through hole 1103.

For example, in some embodiments of the present application, the material of the second insulating member 170 may include insulating PPS (polyphenylene sulfide). In other embodiments, the second insulating member 170 may also be made of other insulating materials such as polypropylene and polyethylene. For example, in some embodiments of the present application, the resistance of the second insulating member 170 in the battery cell 10 may be greater than or equal to 200 MΩ.

In the above scheme, the second insulating member 170 has a simple structure. On the one hand, the second electrode terminal 16 is allowed to pass through the seventh through hole 17001, so that the second electrode terminal 16 is electrically connected to the electrode assembly 12 and external charging and discharging is realized. The second deformable member 18 is allowed to deform through the eighth through hole 17002 so as to be able to contact the third part 160 to achieve overcharge protection; on the other hand, the second insulating member 170 can effectively insulate and isolate the third part 160 and the first wall 110, reducing the risk of internal short circuit of the battery cell 10 due to short circuit between the third part 160 and the first wall 110, so that the reliability of the battery is high.

According to some embodiments of the present application, referring to FIG. 12 , the second insulating member 170 includes a second body 1700 and a third flange 1701, the second body 1700 is located between the third portion 160 and the first wall 110, the third flange 1701 is arranged on a surface of the second body 1700 facing away from the first wall 110, and the third flange 1701 surrounds at least a portion of the outer peripheral surface of the third portion 160.

In some embodiments, the second body 1700 is sandwiched between the third portion 160 and the first wall 110 , and the second body 1700 is flat. The third flange 1701 is protruded from the surface of the second body and surrounds the outer circumference of the third portion 160 .

“The third flange 1701 surrounds at least a portion of the outer circumference of the third part 160 ” can be understood as the third flange 1701 can completely cover the outer circumference of the third part 160 or the third flange 1701 can partially cover the outer circumference of the third part 160 .

In some embodiments, referring to FIG. 12 , the second insulating member 170 wraps the third portion 160 and is located in the second positioning groove 110 c 2 , and the third flange 1701 is located between the outer circumference of the third portion 160 and the wall of the first positioning groove.

In the above scheme, by setting the second body 1700 and the third flange 1701, the first wall 110 and the third part 160 can be effectively insulated and isolated, so that there is a longer creepage distance between the third part 160 and the first wall 110, and the second insulating member 170 has higher insulation performance, effectively reducing the risk of internal short circuit of the battery cell 10 due to short circuit between the first wall 110 and the second electrode terminal 16, so that the reliability of the battery is high.

According to some embodiments of the present application, referring to FIG. 12 , the second insulating member 170 further includes a fourth flange 1702 . The fourth flange 1702 is disposed around the seventh through hole 17001 and is located between the hole wall of the fifth through hole 1102 and the second electrode terminal 16 .

The fourth flange 1702 is part of the second insulating member 170. It is connected to the second body 1700 and disposed around the seventh through-hole 17001. Along the thickness direction z of the first wall, the fourth flange 1702 protrudes toward the fifth through-hole 1102 to cover a portion of the wall of the fifth through-hole 1102, thereby insulating and isolating the second electrode terminal 16 from the wall of the fifth through-hole 1102. In some embodiments, the fourth flange 1702 also serves as a positioning mechanism. By aligning the fourth flange 1702 with the fifth through-hole 1102, the second insulating member 170 can be quickly assembled to the first wall 110.

In some embodiments, the fourth flange 1702 may partially or completely cover the hole wall of the fifth through hole 1102 .

In the above solution, by providing the fourth flange 1702, the hole wall of the fifth through hole 1102 and the second electrode terminal 16 can be effectively insulated and isolated, reducing the risk of the second electrode terminal 16 contacting the hole wall of the fifth through hole 1102 and causing an internal short circuit in the battery cell 10, thereby effectively improving the reliability of the battery.

In some embodiments, referring to Figures 5 and 12, the second insulating portion 17 may further include a second sealing portion 171, which may be sleeved on the fourth portion 161, with a portion of the second sealing portion 171 clamped between the fifth through hole 1102 and the fourth portion 161, and another portion of the second sealing portion 171 clamped between the surface of the first wall 110 facing away from the third portion 160 and the fourth portion 161.

According to some embodiments of the present application, the resistance value of the second insulating portion 17 is greater than or equal to 200 megohms.

In some embodiments, a second insulating portion 17 having a resistance greater than or equal to 200 megohms may be provided between the first wall 110 and the second electrode terminal 16. That is, in some embodiments, the resistance of the second insulating portion 17 may be 200 megohms, 210 megohms, 220 megohms, or greater.

In some embodiments, the resistance of the second insulating portion 17 can be measured by a multimeter test method, a bridge measurement method, a volt-ampere method, an ohmmeter method, etc. In some embodiments, the resistance of the second insulating portion 17 can be measured by a megohmmeter.

In the above scheme, by setting the resistance value of the second insulating portion 17 to be greater than or equal to 200 megohms, the high-voltage insulation resistance between the second electrode terminal 16 and the first wall 110 can be effectively improved, which can effectively meet the insulation voltage requirements of the energy storage device and reduce the risk of external voltage breaking through the second insulating portion 17 and conducting the first wall 110 and the second electrode terminal 16, causing an internal short circuit in the battery cell 10, so that the energy storage device has higher reliability.

According to some embodiments of the present application, the resistance of the first insulating portion 14 is greater than or equal to 200 megohms.

In some embodiments, a first insulating portion 14 having a resistance greater than or equal to 200 megohms may be provided between the first wall 110 and the first electrode terminal 13. That is, in some embodiments, the resistance of the first insulating portion 14 may be 200 megohms, 210 megohms, 220 megohms, or greater.

In some embodiments, the resistance of the first insulating portion 14 can be measured using a multimeter, bridge measurement, volt-ampere method, ohmmeter method, etc. In some embodiments, the resistance of the second insulating portion 14 can be measured using a megohmmeter.

In the above solution, by setting the resistance value of the first insulating part 14 to be greater than or equal to 200 megohms, the high-voltage insulation resistance between the first electrode terminal 13 and the first wall 110 can be effectively improved, which can effectively meet the insulation voltage requirements of the energy storage device and reduce the risk of external voltage breaking through the first insulating part 14 to conduct the first wall 110 and the first electrode terminal 13, causing an internal short circuit in the battery cell 10, so that the energy storage device has higher reliability.

According to some embodiments of the present application, please refer to Figures 4 and 15. Figure 15 is a schematic diagram of the housing 111 and electrode assembly 12 in some embodiments of the present application. The housing 11 includes a housing 111 and an end cap. The housing 111 has an opening. The first wall 110 is the end cap, which is connected to the housing 111 and closes the opening.

In some embodiments, the housing 11 includes a shell 111 and an end cap. A housing cavity is formed inside the shell 111, and the housing cavity is used to accommodate the electrode assembly 12. The shell 111 has an opening connected to the housing cavity. The end cap is covered on the opening of the shell 111 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 12 and the electrolyte. The end cap can be connected to the shell 111 by welding, bonding, clamping or other connection methods. Optionally, the shell 11 may further include a bottom plate, and openings are formed at both ends of the shell 111, one of the openings is closed by the end cap, and the other opening is closed by the bottom plate.

In some embodiments, the material of the shell 11 can be metal or a combination of metal and non-metal. For example, the shell 11 can be made of metal, such as aluminum, copper, iron, steel or aluminum alloy; for example, part of the shell 11 can be made of metal, and the rest can be made of non-metal, such as the end cover of the shell 11 can be made of metal, and the shell 111 or other parts of the shell 11 can be made of non-metallic materials.

In some embodiments of the present application, the housing 111 may be an aluminum shell.

In some embodiments, the end cap, the first electrode terminal 13 , the second electrode terminal 16 , the first insulating portion 14 , the second insulating portion 17 and other structures may be assembled into an end cap assembly first, and then the end cap assembly may be assembled to the housing 111 .

In the above solution, the housing 11 has a simple structure, which facilitates the assembly of the battery cell 10 and helps improve the battery manufacturing efficiency.

According to some embodiments of the present application, please refer to Figures 15 and 16. Figure 16 is a schematic diagram of the shell 111 and the first insulating layer 19 in some embodiments of the present application.

The inner wall of the housing 111 is provided with a first insulating layer 19 .

The first insulating layer 19 is provided on the inner wall of the shell 111, and can insulate and protect the inner wall of the shell 111. In some embodiments, at the end of the life of the battery cell 10, due to the gas generation caused by the internal charge and discharge cycle of the battery cell 10, there is a false touch event that triggers the first deformable member 15 or the second deformable member 18. If the outer shell 11 is negatively charged due to the deformation of the first deformable member 15 or the second deformable member 18, the outer shell 11 will be electrochemically corroded, and the lithium of the negative electrode will be embedded in the outer shell 11. After the outer shell 11 is embedded with lithium, its volume expands to form a porous structure, which eventually causes corrosion and leakage, thereby causing insulation failure and even worse problems. To this end, a first insulating layer 19 is provided on the inner wall of the shell 111, which can cut off the ion path between the outer shell 11 and the negative electrode, thereby cutting off the electrochemical corrosion reaction.

In some embodiments, during the process of assembling the electrode assembly 12 in the shell 111, there is a situation where metal particles pierce the diaphragm of the electrode assembly 12 due to the manufacturing process, causing the metal particles to conduct electricity between the shell 111 and the negative electrode. For this reason, a first insulating layer 19 is provided on the inner wall of the shell 111. The first insulating layer 19 plays a protective role and can improve the problem of metal particles conducting electricity between the shell 111 and the negative electrode.

In some embodiments, the inner wall of the housing 111 includes the inner surface of the side wall of the housing 111 and also includes the inner surface of the bottom wall of the housing 111 .

In some embodiments, the first insulating layer 19 is a layered structure provided on the inner wall of the housing 111 and has insulating properties. For example, the first insulating layer 19 can be a coating or a thin plate-like, layered structure provided on the inner wall of the housing 111.

In the above solution, by providing a first insulating layer 19 inside the shell 111, the electrolyte inside the shell 111 can be effectively insulated and isolated from the inner wall of the shell 111, thereby reducing the risk of the shell 111 being corroded by the electrolyte and the risk of electrolytic wire leakage, so that the battery has higher reliability.

According to some embodiments of the present application, the first insulating layer 19 is an insulating coating provided on the inner wall of the housing 111 .

In some embodiments, the insulating coating material may include epoxy resin, polyurethane, acrylic resin, polyimide, phenolic resin, etc. The first insulating layer 19 may be coated on the inner wall of the housing 111 by dipping, spraying, electroplating, anodizing, etc.

In the above scheme, by providing an insulating coating on the inner wall of the shell 111, on the one hand, the electrolyte and the shell 111 can be effectively separated, the electrolyte ion path between the motor assembly and the shell 111 can be cut off, and the risk of corrosion of the shell 111 can be reduced; on the other hand, the first insulating layer 19 can be efficiently formed on the inner wall of the shell 111 by spraying or the like, so that the manufacturing efficiency of the battery is high; on the other hand, the insulating coating has high mechanical strength, which can effectively reduce the puncture of metal particles introduced by the manufacturing process, resulting in the electrode assembly 12 and the shell 11 being electrically connected to each other, causing the risk of internal short circuit of the battery cell 10 or the risk of corrosion of the shell 11, so that the reliability of the battery is high.

According to some embodiments of the present application, please refer to Figure 16. Along the first direction y, the inner wall of the shell 111 includes a blank area 19b and an insulating area connected in sequence, the insulating area is provided with a first insulating layer 19, the blank area 19b is connected to the first wall 110, and the first direction y is parallel to the first wall 110 and points to the direction of the electrode assembly 12.

In some embodiments, the first direction y may be parallel to the direction of the first wall 110 pointing toward the electrode assembly 12 , and the first direction y may be the thickness direction z of the first wall.

In some embodiments, along the first direction y, the inner wall of the housing 111 includes a blank area 19b and an insulating area, which are connected in sequence. The blank area 19b may not be provided with the first insulating layer 19, and the blank area 19b may be connected to the first wall 110, for example, by welding the blank area 19b to the outer peripheral surface of the first wall 110. Along the first direction y, the insulating area is located below the first wall 110 and is provided with the first insulating layer 19. Exemplarily, the housing 111 includes side walls and a bottom wall, the first wall 110 being an end cap, the blank area 19b being formed at the top of the inner surface of the side wall, and the insulating area being formed at the remaining position of the inner surface of the side wall and the inner surface of the bottom wall.

In some embodiments, the size of the blank area 19b in the first direction y can be greater than or equal to 5 mm, that is, it can be understood that the blank area 19b can provide the end cover with an area greater than or equal to 5 mm in the first direction y to facilitate welding of the shell 111 and the end cover.

In some embodiments, the blank area 19b may be formed by applying glue to set a non-coating area before preparing the insulating coating, or by cleaning the blank area 19b later through a laser cleaning process.

In the above solution, by providing the blank area 19b, the effect of the first insulating layer 19 on the connection between the housing 111 and the first wall 110 can be reduced. For example, the first wall 110 and the housing 111 are welded to each other, and by providing the blank area 19b, good welding quality can be achieved between the first wall 110 and the housing 111, thereby improving the quality of the battery.

According to some embodiments of the present application, along the second direction x, the projection of the electrode assembly 12 on the inner wall of the shell 111 does not overlap with the blank area 19 b , and the second direction x is perpendicular to the first direction y.

The second direction x is perpendicular to the first direction y. In some embodiments, the first direction y is considered to be the height direction, and the second direction x can be the horizontal direction. "Along the second direction x, the projection of the electrode assembly 12 on the inner wall of the housing 111 does not overlap with the blank area 19b" can be understood to mean that the blank area 19b is located on the side of the electrode assembly 12 closest to the end cap.

In the above scheme, by staggering the electrode assembly 12 and the blank area 19b, the risk of the electrode assembly 12 and the blank area 19b overlapping and causing internal short circuit in the battery cell 10 or the risk of the outer shell 11 being corroded by the electrolyte due to negative charge can be reduced, which can effectively improve the reliability of the battery cell 10 and thus improve the reliability of the battery.

According to some embodiments of the present application, the thickness of the first insulating layer 19 is greater than or equal to 60 μm and less than or equal to 200 μm.

16 , the thickness of the first insulating layer 19 is M, and the value of M can be greater than or equal to 60 μm and less than or equal to 200 μm. For example, the value of M can be 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, ..., 180 μm, 190 μm, 200 μm, or any value between two adjacent values.

In the above solution, by setting the thickness of the first insulating layer 19 to be greater than or equal to 60μm, the first insulating layer 19 can have high mechanical strength and insulation properties, effectively isolating the housing 111 from the electrolyte, reducing the risk of the housing 111 being corroded by the electrolyte due to negative charge, and thus making the battery more reliable. By setting the thickness of the first insulating layer 19 to be less than or equal to 200μm, the first insulating layer 19 can effectively reduce the internal space occupied by the battery cell 10, making the battery cell 10 have a higher volumetric energy density, and thus making the battery have a higher volumetric energy density. To this end, by setting the thickness of the first insulating layer 19 to be greater than or equal to 60μm and less than or equal to 200μm, both battery reliability and volumetric energy density can be taken into account.

According to some embodiments of the present application, the thickness of the first insulating layer 19 is greater than or equal to 80 μm and less than or equal to 130 μm.

The thickness of the first insulating layer 19 is M, which may be greater than or equal to 80 μm and less than or equal to 130 μm. For example, M may be 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, or any value between two adjacent values.

In the above solution, by setting the thickness of the first insulating layer 19 to be greater than or equal to 80 μm, the first insulating layer 19 can further have higher mechanical strength and insulation performance, effectively isolating the housing 111 from the electrolyte, reducing the risk of the housing 111 being corroded by the electrolyte due to negative charge, and thus making the battery more reliable. By setting the thickness of the first insulating layer 19 to be less than or equal to 130 μm, the first insulating layer 19 can further reduce the space occupied by the first insulating layer 19 in the internal space of the battery cell 10, so that the battery cell 10 has a higher volumetric energy density, and the battery has a higher volumetric energy density. To this end, by setting the thickness of the first insulating layer 19 to be greater than or equal to 80 μm and less than or equal to 130 μm, it is possible to effectively balance the reliability and volumetric energy density of the battery.

According to other embodiments of the present application, please refer to Figure 17, which is a schematic diagram of the housing 111 and the first insulating layer 19 in other embodiments of the present application. The outer surface of the housing 111 is provided with a second insulating layer 19a.

In some embodiments, the outer surface of the shell 111 is the surface of the shell 111 that contacts the outside world. For example, the outer surface of the shell 111 includes the outer surface of the side wall of the shell 111 and the outer surface of the bottom wall of the shell 111 .

In some embodiments, the second insulating layer 19a is a layered structure provided on the outer surface of the housing 111 and has insulating properties. For example, the second insulating layer 19a can be a coating or a thin plate-like, layered structure provided on the outer surface of the housing 111.

For example, the second insulating layer 19a may be an insulating coating, and the insulating coating may be made of epoxy resin, polyurethane, acrylic resin, polyimide, phenolic resin, etc. The second insulating layer 19a may be coated on the outer surface of the housing 111 by dipping, spraying, electroplating, anodizing, or other processes.

In the above solution, by providing a second insulating layer 19a on the outer surface of the shell 111, the shell 111 can be effectively insulated and protected, reducing the risk of corrosion by the electrolyte due to negative charge of the shell 111, so that the battery has higher reliability.

According to some embodiments of the present application, a battery is further provided, comprising the battery cell 10 described above. Referring to FIG3 , the battery 100 includes the battery cell 10 and a housing 20 , wherein the battery cell 10 is housed within the housing 20 . The housing 20 is used to accommodate the battery cell 10 and can have various structures.

In the battery 100 , there may be one or more battery cells 10 , and each battery cell 10 may be fixed to the case 20 via a connector (such as a bolt), or each battery cell 10 may be fixed to the case 20 by bonding.

According to some embodiments of the present application, an energy storage device is further provided, and the energy storage device includes the battery cell 10 described above.

In some embodiments, battery cells 10 are first formed into a battery, and one or more of these cells are then used in an energy storage device. Referring to Figure 2 , energy storage device 2000 may include a cabinet 2001 and multiple batteries 100. Multiple batteries 100 may be housed within cabinet 2001. Multiple batteries 100 may be connected in series, parallel, or in a hybrid configuration.

According to some embodiments of the present application, an electric device is further provided, comprising the above-described battery cell 10. In some embodiments, the battery cell 10 first forms a battery 100, and one or more batteries 100 are then used in the electric device.

In some embodiments, referring to FIG1 , the electrical device is a vehicle 1000 . A controller 200 , a motor 300 , and a battery 100 may be provided inside the vehicle 1000 . The controller 200 is used to control the battery 100 to supply power to the motor 300 .

According to some embodiments of the present application, a battery cell 10 is provided, see Figures 4 to 17 .

The battery cell 10 includes a housing 11 , an electrode assembly 12 , a first electrode terminal 13 , a first insulating portion 14 , a first deformable member 15 , a second electrode terminal 16 , a second insulating portion 17 , and a second deformable member 18 .

The housing 11 includes a shell 111 and an end cap. The shell 111 has an interior formed with a receiving cavity for receiving the electrode assembly 12. The shell 111 has an opening communicating with the receiving cavity. The end cap closes the opening of the shell 111, so that the electrode assembly 12 is in a closed space.

The end cap includes a main body 110a, a first reinforcement portion 110b, and a second reinforcement portion 110c. The first reinforcement portion 110b includes a first protrusion 110b0 located outside the main body 110a and a first recess 110b1 located inside the main body 110a. The first protrusion 110b0 and the first recess 110b1 are arranged opposite each other in the thickness direction of the end cap. The second reinforcement portion 110c includes a second protrusion 110c0 located outside the main body 110a and a second recess 110c1 located inside the main body 110a. The first protrusion 110b0 is formed with a first positioning groove 110b2, and the second protrusion 110c0 is formed with a second positioning groove 110c2. The first positioning groove 110b2 is formed with a first through hole 1100 and a second through hole 1101, while the second positioning groove 110c2 is formed with a fifth through hole 1102 and a sixth through hole 1103.

In some embodiments, the protrusion height of the first protrusion 110b0 may be greater than or equal to 0.5 mm and less than or equal to 3 mm. In some embodiments, the protrusion height of the second protrusion 110c0 may be greater than or equal to 0.5 mm and less than or equal to 3 mm.

The first electrode terminal 13 is mounted in the first through-hole 1100. Along the thickness of the end cap, the first electrode terminal 13 includes a first portion 130 located on the outside of the end cap and a second portion 131 located at least partially on the inside of the end cap. The first portion 130 is used for electrical connection to external components, while the second portion 131 is electrically connected to the first tab 120 of the electrode assembly 12 via the first adapter 123. The first insulating portion 14 includes a first insulating member 140. In some embodiments, the resistance of the first insulating member 140 is at least 200 megohms or greater. The first insulating member 140 includes a first body 1400, a first flange 1401, and a second flange 1402. The first body 1400 is located between the first portion 130 and the end cap. The first body 1400 is formed with a third through-hole 14001 and a fourth through-hole 14002. The third through-hole 14001 corresponds to the first through-hole 1100 and is provided for the first electrode terminal 13 to pass through. The fourth through-hole 14002 corresponds to the second through-hole 1101. The first flange 1401 is disposed on the surface of the first body 1400 away from the end cap and surrounds the outer circumference of the first portion 130. The second flange 1402 is disposed around the third through hole 14001 and is located between the hole wall of the first through hole 1100 and the first electrode terminal 13.

The first deformable member 15 is welded to the inner side of the end cap and seals the second through-hole 1101. The first deformable member 15 may be a flip tab. The first deformable member 15 is configured to deform to partially pass through the second through-hole 1101 and contact the first portion 130. For example, the first deformable member 15 is configured to deform to partially pass through the second through-hole 1101 and contact the first portion 130 when the internal pressure of the battery cell 10 reaches a first threshold.

The second electrode terminal 16 is mounted in the fifth through-hole 1102. Along the thickness of the end cap, the second electrode terminal 16 includes a third portion 160 located on the outside of the end cap and a fourth portion 161 located at least partially on the inside of the end cap. The fourth portion 161 is connected to the second tab 121 of the electrode assembly 12 via the second adapter 124. The second insulating portion 17 includes a second insulating member 170. In some embodiments, the resistance of the second insulating member 170 is at least 200 megohms or greater. The second insulating member 170 includes a second body 1700, a third flange 1701, and a fourth flange 1702. The second body 1700 is located between the third portion 160 and the end cap. The second body 1700 is formed with a seventh through-hole 17001 and an eighth through-hole 17002. The seventh through-hole 17001 corresponds to the fifth through-hole 1102 and is provided for the second electrode terminal 16 to pass through. The eighth through-hole 17002 corresponds to the sixth through-hole 1103. The third flange 1701 is disposed on the surface of the second body 1700 away from the end cap and surrounds the outer circumference of the third portion 160. The fourth flange 1702 is disposed around the seventh through hole 17001 and is located between the hole wall of the fifth through hole 1102 and the second electrode terminal 16.

The second deformable member 18 is welded to the inner side of the end cap and closes the sixth through hole 1103. The second deformable member 18 can be a flip tab. The second deformable member 18 is configured to deform when the internal pressure of the battery cell 10 reaches a first level, such as a second threshold, so as to partially pass through the sixth through hole 1103 and contact the third portion 160.

In some embodiments, when the second electrode terminal 16 is a negative electrode terminal, the second threshold value may be greater than the first threshold value.

In some embodiments, when a battery cell 10 is subjected to abuse due to overcharging or other conditions, the internal pressure of the battery cell 10 increases. When the internal pressure of the battery cell 10 reaches a certain level, such as a first threshold, the first deformable member 15 deforms, short-circuiting the first electrode terminal 13 and the outer casing 11. When the internal pressure of the battery cell 10 reaches a second threshold, the second deformable member 18 deforms, short-circuiting the second electrode terminal 16 and the outer casing 11, thereby short-circuiting the positive and negative electrodes within the battery cell 10 and creating an internal short circuit. The resulting high current can melt the electrical connections within the battery cell 10, severing the charge and discharge circuit of the battery cell 10, thereby providing overcharge protection. The fused electrical connections can include the first adapter 123 and/or the second adapter 124. For example, the first adapter 123 has a first fuse portion, the flow area of which can be smaller than the flow area of the remaining portions of the first adapter 123. This allows the first fuse portion to melt when a large current flows, thereby severing the current path between the first tab 120 and the first electrode terminal 13. Exemplarily, the second adapter 124 has a second fuse portion, and the flow area of the second fuse portion can be smaller than the flow area of the rest of the second adapter 124, so that when a larger current passes through, the second fuse portion can be melted, thereby disconnecting the current path between the second electrode tab 121 and the second electrode terminal 16.

In the above solution, the provision of the first insulating portion 14 and the second insulating portion 17 effectively insulates and isolates the end cap from the first electrode terminal 13, as well as the second electrode terminal 16. This reduces the risk of internal short circuits in the battery cell 10 due to short circuits between the end cap and the electrode terminal, thereby enhancing battery reliability. In particular, in energy storage devices with higher operating voltages, the provision of the first insulating portion 14 and the second insulating portion 17 effectively reduces the risk of thermal runaway of the energy storage device due to the runaway of the remaining battery cells 10 in the battery, which could cause the outer casing 11 to be charged with high voltage, leading to high voltage conduction between the end cap and the electrode terminal, and thus causing internal short circuits in the battery cell 10.

In some embodiments, the inner wall of the housing 111 is provided with a first insulating layer 19, which may be an insulating coating. The insulating coating may be made of epoxy resin, polyurethane, acrylic resin, polyimide, phenolic resin, etc. The first insulating layer 19 may be applied to the inner wall of the housing 111 by a process such as dipping, spraying, electroplating, or anodizing.

In some embodiments, the insulation resistance of the first insulating layer 19 can meet 1000V, 5s, >1GΩ. In some embodiments, the first insulating layer 19 is an insulating coating, which can meet the following conditions: electrolyte resistance at 60°C without swelling.

In some embodiments, to ensure higher welding quality between the end cap and the shell 111, the interior of the shell 111 can be set in a blank area 19b, where the first insulating layer 19 is not set, and the blank area 19b and the end cap are welded to each other.

In the above scheme, by providing an insulating coating on the inner wall of the shell 111, on the one hand, the electrolyte and the shell 111 can be effectively separated, the electrolyte ion path between the motor assembly and the shell 111 can be cut off, and the risk of corrosion of the shell 111 can be reduced; on the other hand, the first insulating layer 19 can be efficiently formed on the inner wall of the shell 111 by spraying or the like, so that the manufacturing efficiency of the battery is high; on the other hand, the insulating coating has high mechanical strength, which can effectively reduce the puncture of metal particles introduced by the manufacturing process, resulting in the electrode assembly 12 and the shell 11 being electrically connected to each other, causing the risk of internal short circuit of the battery cell 10 or the risk of corrosion of the shell 11, so that the reliability of the battery is high.

The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims (40)

A battery cell, comprising: a housing having a first wall; an electrode assembly, disposed in the housing; a first electrode terminal, disposed on the first wall and electrically connected to the electrode assembly, the first electrode terminal being used for input and output of electrical energy; The first insulating portion is provided between the first wall and the first electrode terminal, and is used for insulating and isolating the first electrode terminal from the first wall. The battery cell according to claim 1, further comprising: A first deformable member is electrically connected to the first wall, and the first deformable member is configured to be deformable to contact the first electrode terminal to electrically connect the first electrode terminal to the first wall. The battery cell according to claim 2, wherein: The first wall is formed with a first through hole and a second through hole, the first electrode terminal passes through the first through hole, the first deformable member closes the second through hole, and the first deformable member is configured to be deformable to partially pass through the second through hole and contact the first electrode terminal. The battery cell according to claim 2 or 3, wherein: Along the thickness direction of the first wall, a projection of a first portion of the first electrode terminal located outside the first wall at least partially overlaps with a projection of the first deformable member. The battery cell according to any one of claims 1 to 4, wherein: The length of the first wall is greater than or equal to 150 mm, and the width of the first wall is greater than or equal to 45 mm. The battery cell according to any one of claims 1 to 5, wherein: The first wall includes a main body portion and a first reinforcement portion connected to each other, and a first portion of the first electrode terminal located outside the first wall is disposed on the first reinforcement portion. The battery cell according to claim 6, wherein: The first reinforcement portion includes a first protrusion along a thickness direction of the first wall. The first protrusion protrudes from one surface of the body portion along the thickness direction of the first wall. The battery cell according to claim 7, wherein: The first reinforcement portion further includes a first recessed portion. The first recessed portion is disposed on the other surface of the main body portion along a thickness direction of the first wall, and the first recessed portion is disposed opposite to the first protruding portion. The battery cell according to claim 7 or 8, wherein the first protrusion is located on the outside of the first wall, and the first protrusion is formed with a first positioning groove, and the first positioning groove accommodates the first part to limit the movement of the first part. The battery cell according to any one of claims 7 to 9, wherein: The first convex portion is located on the outer side of the first wall. Along the thickness direction of the first wall, the dimension of the first convex portion protruding from the main body portion is greater than or equal to 0.1 mm and less than or equal to 5 mm. The battery cell according to any one of claims 7 to 10, wherein: Along the thickness direction of the first wall, a dimension of the first protrusion protruding from the main body is greater than or equal to 0.5 mm and less than or equal to 3 mm. The battery cell according to claim 3, wherein: The first insulating portion includes a first insulating member, at least a portion of which is arranged between a first portion of the first electrode terminal located on the outside of the first wall and the first wall, and the first insulating member is formed with a third through hole and a fourth through hole. Along the thickness direction of the first wall, the third through hole is arranged opposite to the first through hole, and the fourth through hole is arranged opposite to the second through hole. The battery cell according to claim 12, wherein: The first insulating member includes a first body and a first flange. The first body is located between the first part and the first wall. The first flange is arranged on a surface of the first body away from the first wall. The first flange surrounds at least a portion of the outer circumference of the first part. The battery cell according to claim 13, wherein: The first insulating member further includes a second flange, which is disposed around the third through hole and is located between a hole wall of the first through hole and the first electrode terminal. The battery cell according to any one of claims 2 to 14, further comprising: a second electrode terminal, disposed on the first wall and electrically connected to the electrode assembly, the second electrode terminal being used for inputting and outputting electrical energy, and having opposite polarity to the first electrode terminal; a second insulating portion, provided between the first wall and the second electrode terminal, for insulating and isolating the second electrode terminal from the first wall; a second deformable member electrically connected to the first wall, wherein the second deformable member is configured to be deformable so as to contact the second electrode terminal to electrically connect the second electrode terminal to the first wall. The battery cell according to claim 15, wherein The second electrode terminal is a negative electrode terminal, so that a minimum pressure value causing deformation of the second deformable member is greater than a minimum pressure value causing deformation of the first deformable member. The battery cell according to any one of claims 15-16, wherein: The first wall is formed with a fifth through hole and a sixth through hole, the second electrode terminal passes through the fifth through hole, the second deformable member closes the sixth through hole, and the second deformable member is configured to be deformable to partially pass through the sixth through hole and contact the second electrode terminal. The battery cell according to claim 17, wherein: Along the thickness direction of the first wall, a projection of a third portion of the second electrode terminal located outside the first wall at least partially overlaps with a projection of the second deformable member. The battery cell according to claim 17 or 18, wherein: The first wall includes a main body portion and a second reinforcement portion connected to each other, and a third portion of the second electrode terminal located outside the first wall is disposed on the second reinforcement portion. The battery cell according to claim 19, wherein: The second reinforcement portion includes a second protrusion protruding from one surface of the body portion in the thickness direction of the first wall. The battery cell according to claim 20, wherein The second reinforcement portion further includes a second recessed portion. The second recessed portion is provided on the other surface of the main body portion along the thickness direction of the first wall, and the second recessed portion is provided opposite to the second protruding portion. The battery cell according to claim 20 or 21, wherein: The second protrusion is located on the outer side of the first wall. The second protrusion is formed with a second positioning groove. The second positioning groove accommodates the third part to limit the movement of the third part. The battery cell according to any one of claims 20 to 22, wherein: The second convex portion is located on the outer side of the first wall. Along the thickness direction of the first wall, the dimension of the second convex portion protruding from the main body portion is greater than or equal to 0.1 mm and less than or equal to 5 mm. The battery cell according to claim 23, wherein Along the thickness direction of the first wall, a dimension of the second protrusion protruding from the main body is greater than or equal to 0.5 mm and less than or equal to 3 mm. The battery cell according to any one of claims 17 to 24, wherein: The second insulating portion includes a second insulating member, at least a portion of which is arranged between the third portion of the second electrode terminal located on the outside of the first wall and the first wall, and the second insulating member is formed with a seventh through hole and an eighth through hole. Along the thickness direction of the first wall, the seventh through hole is arranged opposite to the fifth through hole, and the eighth through hole is arranged opposite to the sixth through hole. The battery cell according to claim 25, wherein The second insulating member includes a second body and a third flange. The second body is located between the third part and the first wall. The third flange is arranged on the surface of the second body away from the first wall. The third flange surrounds at least part of the outer circumference of the third part. The battery cell according to claim 26, wherein The second insulating member further includes a fourth flange, which is disposed around the seventh through hole and is located between a hole wall of the fifth through hole and the second electrode terminal. The battery cell according to any one of claims 15 to 27, wherein: The resistance value of the second insulating portion is greater than or equal to 200 megohms. The battery cell according to any one of claims 1 to 28, wherein: The resistance value of the first insulating portion is greater than or equal to 200 megohms. The battery cell according to any one of claims 1 to 29, wherein: The housing comprises a shell and an end cover, wherein the shell has an opening; The first wall is the end cover, which is connected to the shell and closes the opening. The battery cell according to claim 30, wherein: The inner wall of the shell is provided with a first insulating layer. The battery cell according to claim 31, wherein The first insulating layer is an insulating coating provided on the inner wall of the shell. The battery cell according to claim 31 or 32, wherein: Along the first direction, the inner wall of the shell includes a blank area and an insulating area connected in sequence, the insulating area is provided with the first insulating layer, the blank area is connected to the first wall, and the first direction is parallel to the first wall and points to the direction of the electrode assembly. The battery cell according to claim 33, wherein Along a second direction, a projection of the electrode assembly on the inner wall of the shell does not overlap with the blank area, and the second direction is perpendicular to the first direction. The battery cell according to any one of claims 31 to 34, wherein: The thickness of the first insulating layer is greater than or equal to 60 μm and less than or equal to 200 μm. The battery cell according to any one of claims 31 to 35, wherein: The thickness of the first insulating layer is greater than or equal to 80 μm and less than or equal to 130 μm. The battery cell according to any one of claims 30 to 36, wherein: A second insulating layer is provided on the outer surface of the shell. A battery comprising the battery cell according to any one of claims 1 to 37. An energy storage device, comprising the battery cell according to any one of claims 1 to 37. An electrical device, comprising a battery cell according to any one of claims 1 to 37, wherein the battery cell is used to provide electrical energy.