CN223006817U - Winding needle and winding equipment - Google Patents

Abstract

The application discloses a roll needle and winding equipment, roll needle includes: an inner needle; at least two outer needles surrounding the inner needle along the circumference of the inner needle, the outer needles being movably disposed at the circumferential side of the inner needle along the radial direction of the inner needle; the first structural member is propped against the outer needle and can move relative to the outer needle along the axial direction of the inner needle so as to push the outer needle to be far away from the inner needle along the radial direction of the inner needle; according to the winding needle, the outer needle is pushed to be far away from the inner needle along the radial direction of the inner needle through the first structural member, so that the effect of expanding the outer diameter of the winding needle is achieved; simultaneously, the first structural part can be separated from the outer needle, and at the moment, the electrode assembly can apply pressure to the winding needle so that the outer needle can be close to the inner needle along the radial direction of the inner needle, thereby achieving the effect of reducing the outer diameter of the winding needle; the outer diameter of the winding needle can be increased or reduced, so that the outer diameter of the winding needle can be adjusted in the winding process of the electrode assembly, and the occurrence of dislocation of the tab is reduced.

Description

Winding needle and winding equipment

Technical Field

The application relates to the technical field of battery processing, in particular to a winding needle and winding equipment.

Background

Energy conservation and emission reduction are key to sustainable development of the automobile industry, and electric vehicles become an important component of sustainable development of the automobile industry due to the energy conservation and environmental protection advantages of the electric vehicles. For electric vehicles, battery technology is an important factor in the development of the electric vehicles.

Winding of the electrode assembly is a very important process during battery processing, and the electrode assembly is generally required to be wound through a winding needle. The current winding needle is easy to have the condition of dislocation of the tab in the winding process, so that the yield of the electrode assembly is lower.

Disclosure of utility model

In view of the above, the present application provides a winding needle and a winding apparatus, which can alleviate the problem of low yield caused by dislocation of tabs during winding of an electrode assembly.

In a first aspect, an embodiment of the present application provides a winding needle, including:

an inner needle;

At least two outer needles surrounding the inner needle along the circumference of the inner needle, the outer needles being movably disposed at the circumferential side of the inner needle along the radial direction of the inner needle;

The first structural member is propped against the outer needle and can move relative to the outer needle along the axial direction of the inner needle so as to push the outer needle to be far away from the inner needle along the radial direction of the inner needle.

In the technical scheme of the embodiment, the outer needle which surrounds the inner needle and can move along the radial direction of the inner needle is arranged, the first structural member which is propped against the outer needle is arranged, the outer needle is pushed to be away from the inner needle along the radial direction of the inner needle by the first structural member, so that the effect of expanding the outer diameter of the winding needle is achieved, meanwhile, the first structural member can be separated from the outer needle, at the moment, under the action of tension in the winding process of the electrode assembly, the electrode assembly can apply pressure to the winding needle to enable the outer needle to be close to the inner needle along the radial direction of the inner needle, so that the effect of reducing the outer diameter of the winding needle is achieved, and the outer diameter of the winding needle can be increased or reduced, so that the outer diameter of the winding needle can be adjusted in the winding process of the electrode assembly, and the occurrence of polar lug dislocation is reduced.

In some embodiments, the winding needle further comprises an elastic member disposed in the winding needle, one end of the elastic member being connected to the outer needle, and the other end of the elastic member being connectable to the inner needle or the other outer needle, the elastic member being adapted to apply a force to the outer needle directed in the direction of the inner needle.

In the technical scheme of this embodiment, apply the force of pointing to the needle direction in to the outer needle through the elastic component to make the elastic component can hold outer needle pressure in first structure, and make first structure can cooperate the elastic component to drive outer needle along the radial of interior needle be close to or keep away from interior needle motion, thereby make the book needle have the function of enlarging the external diameter and reducing the external diameter, and then the condition that the electrode assembly winding in-process utmost point ear dislocation of better reduction appears of being convenient for.

In some embodiments, the first structural member includes a first bevel inclined relative to the axis of the inner needle and forming a first angle with the axis of the inner needle, the first bevel being held against the outer needle such that the outer needle is movable along the first bevel relative to the first structural member.

In the technical scheme of the embodiment, the first structural member comprises a first inclined surface, the first inclined surface is abutted against the outer needle, at the moment, the first structural member can move to push the outer needle to move along the first inclined surface in a direction away from the inner needle, and meanwhile, under the action of tension of the elastic piece or the electrode assembly, the outer needle can also be close to the inner needle along the first inclined surface when the first structural member moves reversely, so that the outer diameter of the winding needle can be enlarged or reduced.

In some embodiments, the first included angle ranges from 40 ° to 50 °.

The technical scheme of the embodiment provides the included angle range of some first inclined planes so as to limit the distance that the outer needle can radially move along the inner needle through the included angle of the first inclined planes, so that the change of the outer diameter of the winding needle can be regulated by the shorter distance of the movement of the first structural member, the regulation of the outer diameter of the winding needle can have higher response speed, and meanwhile, the resistance between the first structural member and the outer needle can be reduced, thereby reducing the friction loss between the first structural member and the outer needle and prolonging the service life of the winding needle.

In some embodiments, the length of the first inclined plane ranges from 3mm to 5mm.

The technical scheme of the embodiment provides the length range of some first inclined planes so as to limit the distance that the outer needle can radially move along the inner needle through the length of the first inclined planes, thereby limiting the change range of the outer diameter of the winding needle and reducing the occurrence of the condition of dislocation of the tab in the winding process of the electrode assembly.

In some embodiments, the winding needle further comprises a second structural member, the second structural member and the first structural member are respectively arranged at two opposite ends of the inner needle along the axial direction of the inner needle, the second structural member is abutted against the outer needle at least along the axial direction of the inner needle, and the first structural member can move relative to the second structural member along the axial direction of the inner needle.

In the technical scheme of the embodiment, the first structural member and the second structural member are arranged at two ends of the inner needle, the first structural member and the second structural member can respectively prop against two ends of the outer needle, and the outer needle can always prop against the second structural member in the process of moving the first structural member and pushing the outer needle to move along the radial direction of the inner needle so as to support the outer needle together by the cooperation of the second structural member and the first structural member, so that the stability of the outer needle in the moving process can be improved, and the situation that the outer needle is inclined in the moving process is reduced.

In some embodiments, the second structural member includes a second bevel, the second bevel bearing against the outer needle, the second bevel forming a second angle with the axis of the inner needle;

The projection of the intersection of the plane of the second inclined plane and the plane of the first inclined plane along the radial direction of the inner needle is positioned in the middle area of the inner needle.

In the technical scheme of the embodiment, the second inclined plane is arranged on the second structural member, the intersection of the second inclined plane and the first inclined plane is located in the middle area of the inner needle, so that the inclined directions of the first inclined plane and the second inclined plane are opposite, and in the process that the first structural member moves and pushes the outer needle to move, the outer needle can be always abutted to the second inclined plane and move along the second inclined plane, so that the outer needle is supported by the second inclined plane, and the stability of the movement of the outer needle is improved.

In some embodiments, the second included angle is equal to the first included angle.

In the technical scheme of this embodiment, make the inclination of second inclined plane and first inclined plane the same to make first structure motion and promote outer needle in-process that removes, outer needle can be all the time in the butt and along second inclined plane motion of second inclined plane, with the outer needle of support through the second inclined plane, thereby further improve outer needle motion's stability, reduce outer needle and appear crooked etc. condition in the motion process.

In some embodiments, the outer needle is provided with two third structural members, the two third structural members are arranged at two ends of the outer needle along the axial direction of the inner needle, and the two third structural members are respectively propped against the first structural member and the second structural member.

In the technical scheme of this embodiment, set up two third structures on the outer needle to support respectively in first structure and second structure, so that first structure and second structure can all be through third structure bearing outer needle, thereby can increase the stability of outer needle motion in-process, reduce the outer needle and appear crooked etc. condition in the motion in-process.

In some embodiments, each of the two third structures includes a third ramp, one of the two third ramps being parallel to and abutting the adjacent first ramp, and the other of the two third ramps being parallel to and abutting the adjacent second ramp.

In the technical scheme of the embodiment, the third inclined plane is arranged on the third structural member, and the two third inclined planes are respectively parallel to the adjacent first inclined plane or second inclined plane, so that the third structural member is in surface contact with the first structural member and the second structural member, the stability of contact between the third structural member and the first structural member and between the third structural member and the second structural member can be improved, the stability of the outer needle in the movement process can be further improved, and the conditions of skew and the like of the outer needle in the movement process are reduced.

In some embodiments, the first structural member is fixedly connected to the inner needle, and the winding needle further comprises a drive assembly for driving the inner needle to move axially along the inner needle to push the outer needle radially away from the inner needle through the first structural member.

The technical scheme of this embodiment provides some concrete structures that drive first structure moved, drives the motion of interior needle through drive assembly to drive first structure motion through interior needle, so that first structure can promote outer needle motion, thereby reaches the effect of adjusting the needle external diameter.

In some embodiments, the outer needles are provided with air inlet holes, at least two outer needles can enclose an air flow space, the air flow space is communicated with the air inlet holes, and the air flow space is used for being communicated with the air suction device so as to form negative pressure in the air flow space.

In the technical scheme of the embodiment, the air extractor can extract the air in the air flow space out of the winding needle so as to form negative pressure in the air flow space, and the negative pressure in the air flow space can adsorb the electrode assembly near the air inlet hole on the outer needle so as to achieve the effect of fixing the electrode assembly.

In some embodiments, there are at least two air inlet holes, and the at least two air inlet holes are evenly arranged on the outer needle.

In the technical scheme of the embodiment, at least two air inlets are formed, so that the outer needle can be provided with at least two positions for adsorbing the electrode assemblies, the stability of fixing the electrode assemblies can be improved, the fixing effect can be improved, and the at least two air inlets are uniformly distributed, so that the adsorption force applied to the electrode assemblies can be relatively uniform, and the deformation and other anomalies possibly caused by uneven stress of the electrode assemblies are reduced.

In some embodiments, the aperture range of the air inlet holes is 1 mm-2 mm, and the distance between two adjacent air inlet holes is 2 mm-4 mm.

The technical scheme of the embodiment provides the aperture range and the interval range of a plurality of air inlets, so that the air inlets can be used for stably adsorbing the electrode assembly, and the occurrence of the condition that the electrode assembly or the diaphragm enters the air inlets to cause deformation of the electrode assembly can be reduced.

In some embodiments, the negative pressure ranges from-50 KPa to-75 KPa.

The technical scheme of the embodiment provides the range of negative pressure in some airflow spaces, so that the winding needle can not only stably adsorb the electrode assembly, but also reduce the occurrence of the condition that the electrode assembly or the diaphragm enters the air inlet hole to cause the deformation of the electrode assembly.

In some embodiments, the inner needle is provided with an air flow channel communicated with the air flow space, and one end of the air flow channel is used for being communicated with the air suction device so as to suck the air in the air flow space out of the winding needle through the air flow channel.

In the technical scheme of the embodiment, the air flow channel is formed in the inner needle, so that the air extractor can extract the air in the air flow space through the air flow channel and form negative pressure, the air extractor can extract the air from the air flow space conveniently, meanwhile, the arrangement difficulty of each structure in the winding needle is reduced, and the space is saved.

In some embodiments, the outer needle comprises a middle part, two ends of the middle part along the axial direction of the inner needle are connected with end parts, the end parts are propped against the first structural part, the air inlet hole is at least arranged on the middle part, and the air flow space is at least formed between the middle parts of different outer needles.

In the technical scheme of the embodiment, the outer needle comprises a middle part and an end plate, so that the end part can be abutted against the first structural part, the first structural part can push the outer needle to move, the air inlet hole is formed in the middle part, and the electrode assembly can be fixed by the winding needle nearby the middle part, so that the electrode assembly can be fixed more stably by the winding needle.

In some embodiments, the thickness of the intermediate portion ranges from 5mm to 8mm.

The technical scheme of the embodiment provides thickness ranges of some intermediate parts, so that the intermediate parts not only have stronger strength, but also can reduce occupation of space so that air flow can be smoothly extracted out of the winding needle from the air flow space, and simultaneously, the weight of the outer needle can be reduced.

In some embodiments, the end portions are detachably connected to the intermediate portion.

In the technical scheme of this embodiment, tip detachably connects in the middle part can be convenient for the installation, change and the maintenance of outer needle, simultaneously, also is convenient for the whole equipment of rolling up the needle.

In some embodiments, a lower trough is also arranged on the peripheral side surface of the outer needle, and at least one end of the lower trough is communicated with a space outside the winding needle in the axial direction of the inner needle.

In the technical scheme of the embodiment, the blanking groove is arranged on the outer needle, so that the blanking device can conveniently enter the wound electrode assembly and take the electrode assembly off the winding needle.

In a second aspect, some embodiments of the present application also provide a winding apparatus comprising the winding needle provided by some embodiments of the first aspect.

The foregoing description is only an overview of the present application, and is intended to be implemented in accordance with the teachings of the present application in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present application more readily apparent.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the accompanying drawings. In the drawings:

Fig. 1 is a schematic perspective view of a winding needle according to some embodiments of the present application.

Fig. 2 is a schematic front view of a winding needle according to some embodiments of the present application.

Fig. 3 is a schematic cross-sectional view at A-A in fig. 2.

Fig. 4 is a partially enlarged schematic view at B in fig. 3.

Fig. 5 is an enlarged partial schematic view of fig. 3 at B in another embodiment.

Fig. 6 is an enlarged partial schematic view at C in fig. 3.

The meaning of the labels in the figures is:

100. a winding needle;

10. an inner needle 101, an air flow passage;

20. An outer needle, 201, an airflow space, 21, a middle part, 211, an air inlet hole, 22, an end part, 221, a third structural part, 2211, a third inclined plane, 222, a convex part, 23 and a blanking groove;

30. 31, a first inclined plane;

40. an elastic member;

50. A base, 51, a second structural member, 511, a second inclined surface, 52, a cavity, 53 and an interface;

60. and a drive assembly.

Detailed Description

Embodiments of the technical scheme of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical aspects of the present application, and thus are merely examples, and are not intended to limit the scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs, the terms used herein are for the purpose of describing particular embodiments only and are not intended to be limiting of the application, and the terms "comprising" and "having" and any variations thereof in the description of the application and the claims and the above description of the drawings are intended to cover non-exclusive inclusions.

In the description of embodiments of the present application, the technical terms "first," "second," and the like are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship. In the description of the embodiments of the present application, the meaning of "plurality" is two or more unless explicitly defined otherwise.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

In the description of the embodiment of the present application, the term "and/or" is merely an association relationship describing the association object, and indicates that three relationships may exist, for example, a and/or B, and may indicate that a exists alone, while a and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

In the description of the embodiments of the present application, the term "plurality" means two or more (including two), and similarly, "plural sets" means two or more (including two), and "plural sheets" means two or more (including two).

In the description of the embodiments of the present application, the orientation or positional relationship indicated by the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationship shown in the drawings, and are merely for convenience of description and simplification of the description, and do not indicate or imply that the apparatus or element referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "fixed" and the like are to be construed broadly and include, for example, fixed connection, detachable connection, or integral therewith, mechanical connection, electrical connection, direct connection, indirect connection via an intermediary, communication between two elements, or interaction between two elements. The specific meaning of the above terms in the embodiments of the present application will be understood by those of ordinary skill in the art according to specific circumstances.

Currently, the application of power batteries is more widespread from the development of market situation. The power battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles, electric automobiles, and the like, and a plurality of fields such as military equipment, aerospace, and the like. With the continuous expansion of the application field of the power battery, the market demand of the power battery is also continuously expanding.

Winding of the electrode assembly is a very important process in the battery production process, and the electrode assembly is generally required to be wound through a winding needle. The current winding needle is easy to generate the condition of electrode lug dislocation in the winding process, the current flowing area is easy to be reduced due to the electrode lug dislocation, even the current cannot normally flow, so that the battery capacity is reduced, the electrode lug dislocation also easily causes the too high voltage of partial areas to influence the service life of the battery, the electrode lug dislocation also easily causes the conditions of welding short circuit, off-welding and the like, namely the electrode lug dislocation easily has negative influence on the capacity, service life and safety performance of an electrode assembly.

The dislocation of the tab may be caused by various reasons, such as insufficient equipment precision, deviation of tab materials and dimensions, uneven thickness of the pole piece, etc. The electrode assembly is wound on the winding needle, and the circumference of the outermost layer of the electrode assembly is gradually increased along with the increase of the winding number of the electrode assembly in the process of winding the electrode assembly on the winding needle, and the spacing of the electrode lugs on the electrode assembly is approximately the same, so that dislocation among the electrode lugs of each layer is easily caused.

Based on the above consideration, in order to alleviate the problem of dislocation of the tab in the winding process of the electrode assembly, the embodiment of the application provides a winding needle, which comprises an inner needle and at least two outer needles arranged around the inner needle, wherein a first structural member is arranged, so that the first structural member can move along the axial direction of the inner needle and can push the outer needles to move away from the inner needle along the radial direction of the inner needle, thereby expanding the outer diameter of the winding needle.

In the winding needle, the first structural member can move in one direction along the axial direction of the inner needle to abut against the outer needle and push the outer needle to move so as to enlarge the outer diameter of the winding needle, and along with the winding of the electrode assembly, the first structural member can move in the other direction along the axial direction of the inner needle to separate from the outer needle, and at the moment, under the action of the tension of the winding of the electrode assembly, the outer needle can move in the direction close to the inner needle and is pressed and held on the first structure, so that the outer diameter of the winding needle is reduced, the circumference of the outermost ring of the electrode assembly is correspondingly reduced, and the situation of dislocation of the tab is relieved.

The winding needle and the winding device provided by the embodiment of the application can be wound to form a cylindrical electrode assembly, and also can be wound to form a prismatic electrode assembly or electrode assemblies with other shapes. The electrode assembly formed by the winding apparatus may be used as a component of an electrochemical reaction occurring in a battery cell that may be used in an electric device using a battery as a power source or various energy storage systems using a battery as an energy storage element. The power device may be, but is not limited to, a cell phone, tablet, notebook computer, electric toy, electric tool, battery car, electric car, ship, spacecraft, etc. Among them, the electric toy may include fixed or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric plane toys, and the like, and the spacecraft may include planes, rockets, space planes, and spacecraft, and the like.

The following examples are given by taking a winding apparatus for forming square electrode assemblies according to some embodiments of the present application as an example for convenience of explanation.

In a first aspect, fig. 1-3, some embodiments of the present application provide a winding needle 100, the winding needle 100 comprising an inner needle 10, an outer needle 20, and a first structural member 30. Wherein, there are at least two outer needles 20, and at least two outer needles 20 surround the inner needle 10 along the circumference of the inner needle 10, the first structural member 30 is abutted against the outer needles 20, and the first structural member 30 can move relative to the outer needles 20 along the axial direction of the inner needle 10 to push the outer needles 20 away from the inner needle 10 along the radial direction of the inner needle 10.

In fig. 1 to 3, the direction of the X axis is the axial direction of the winding needle 100 and the axial direction of the inner needle 10, the radial direction of the winding needle 100 is the direction perpendicular to the axial direction of the winding needle 100, for example, the directions of the Y axis and the Z axis are both the radial direction of the winding needle 100 and the radial direction of the inner needle 10, the circumferential direction of the inner needle 10 is the direction around the X axis, and the circumferential direction of the inner needle 10 is also parallel to the plane of the Y axis and the Z axis.

The inner needle 10 refers to a structure of the winding needle 100 inside the winding needle 100, the inner needle 10 is used for driving the winding needle 100 to rotate, the inner needle 10 can be connected with an external driving structure (such as a motor, etc.) and rotate along with the winding needle, namely the external driving structure can drive the winding needle 100 to rotate by driving the inner needle 10 to rotate, the shape of the inner needle 10 can be cylindrical, prismatic or other, and the material of the inner needle 10 can comprise plastics, metals or other materials.

The outer needles 20 refer to a structure of the rolling needle 100, which is in contact with the electrode assembly, the outer needles 20 may be at least two, or three or more, the outer needles 20 may be disposed around the inner needle 10 along the circumferential direction of the inner needle 10, i.e., the outer needles 20 may be spliced to form a sidewall structure of the rolling needle 100 so that the electrode assembly may be wound around the sidewall structure, and the outer needles 20 may cover part of the inner needle 10 at least along the circumferential direction of the inner needle 10 so that the electrode assembly may be wound around the sidewall structure formed by the outer needles 20.

The shape of the outer needle 20 can affect the shape of the winding needle 100 because the at least two outer needles 20 surround the inner needle 10 and are combined to form the sidewall structure of the winding needle 100, and accordingly, the outer needle 20 may have an arc-shaped sheet structure, the winding needle 100 may have a cylindrical structure, the outer needle 20 may have a flat plate structure, the winding needle 100 may have a prismatic structure, and the outer needle 20 may have a shape.

The material of the outer needle 20 may include plastic, metal or other materials, and the material of the outer needle 20 and the material of the inner needle 10 may be the same or different.

The outer needle 20 is movably arranged at the circumference side of the inner needle 10 along the radial direction of the inner needle 10, namely, the outer needle 20 can move relative to the inner needle 10 to approach or separate from the inner needle 10 along the radial direction of the inner needle 10, the outer needle 20 can be directly connected with the inner needle 10 in a sliding manner, and can also move along the radial direction of the inner needle 10 by limiting the guiding structure, for example, a guide rail, a guide shaft or other structures with guiding capability, and the outer needle 20 can move along the guide rail, the guide shaft or other guiding structures, so that the outer needle 20 moves along the radial direction of the inner needle 10.

The first structural member 30 refers to a member capable of moving relative to the inner needle 10 in the winding needle 100, the first structural member 30 may be disposed on the inner needle 10 and move relative to the inner needle 10, or may be disposed on other structures of the winding needle 100 and move relative to the inner needle 10, for example, the first structural member 30 may be a rod-shaped structure, a sheet-shaped structure or other shaped structure disposed on one side of the inner needle 10, or the first structural member 30 may be a ring-shaped structure, a tubular structure or other shaped structure sleeved on the inner needle 10, and the material of the first structural member 30 may include plastics, metals or other materials.

The first structural member 30 is movable relative to the outer needle 20 in the axial direction X of the inner needle 10, and the first structural member 30 abuts against the outer needle 20 such that the first structural member 30 movement can push the outer needle 20 away from the inner needle 10 in the radial direction Y of the inner needle 10. In some embodiments, the first structural member 30 may be a wedge, the outer needle 20 is abutted against a slope of the wedge, and the wedge can move along the slope of the wedge along the axial direction of the inner needle 10 by pushing the outer needle 20 along the slope of the wedge to move away from the inner needle 10, in other embodiments, the first structural member 30 may be a connecting rod, one end of the connecting rod can move along the axial direction of the inner needle 10, the other end of the connecting rod is abutted against the outer needle 20, and one end of the connecting rod can push the other end of the connecting rod away from the inner needle 10 along the axial direction of the inner needle 10, and it is understood that the first structural member 30 may also comprise other structures, but is not limited to the two structures.

The first structural member 30 may abut against the edge of the outer needle 20 in the axial direction X of the inner needle 10, or a structural member may be provided on the side of the outer needle 20 facing the inner needle 10, and the first structural member 30 may abut against the structural member.

Because there are at least two outer needles 20, there may be only one first structural member 30 abutting each outer needle 20, there may be two or more first structural members 30 so that each outer needle 20 corresponds to at least one first structural member 30, and it will be appreciated that in the case of a plurality of first structural members 30, the plurality of first structural members 30 should be capable of moving synchronously to bring the outer needles 20 into synchronous movement.

Movement of the first structural member 30 in the axial direction X of the inner needle 10 may be achieved by a variety of structures. In some embodiments, the inner needle 10 is provided with a sliding groove extending along the axial direction X of the inner needle 10, at least part of the first structural member 30 can be accommodated in the sliding groove and slide along the sliding groove, in other embodiments, the inner needle 10 can be provided with a guiding shaft extending along the axial direction X of the inner diameter, the guiding shaft passes through the first structural member 30, the first structural member 30 can slide along the guiding shaft, and in still other embodiments, the inner needle 10 can pass through the first structural member 30 directly, even if the first structural member 30 is sleeved on the inner needle 10, so that the first structural member 30 can slide along the axial direction X of the inner needle 10.

It will be appreciated that movement of the first structural member 30 in one direction (e.g., right movement in the X-axis direction in fig. 3) may urge the outer needle 20 away from the inner needle 10 to increase the outer diameter of the winding needle 100, but movement of the first structural member 30 in the other direction (e.g., left movement in the X-axis direction in fig. 3) may result in disengagement of the outer needle 20 from the first structural member 30, wherein the first structural member 30 is less likely to move the outer needle 20, and wherein during winding of the electrode assembly around the winding needle 100, the outer diameter of the winding needle 100 is reduced by the pressure exerted by the electrode assembly around the winding needle 100, wherein, for example, tension on the electrode assembly may exert a pressure on the winding needle 100 in the direction of the inner needle 10, and wherein movement of the first structural member 30 in the other direction (e.g., left movement in the X-axis direction in fig. 3) may disengage the outer needle 20 from the first structural member 30, and wherein the pressure generated by the electrode assembly may not provide support to the outer needle 20 in the direction toward the inner needle 10 and re-abut the first structural member 30, thereby achieving the effect of reducing the outer diameter of the winding needle 100.

In the process of winding the electrode assembly around the winding needle 100, the outer diameter of the winding needle 100 can be gradually reduced along with the increase of the winding number of the electrode assembly so as to reduce the occurrence of the dislocation of the tab at the outermost layer of the electrode assembly, and in the process of winding the electrode assembly, the outer diameter of the winding needle 100 can be increased or reduced according to the situation so as to relieve the dislocation of the tab under the condition of the dislocation of the tab caused by other reasons.

In this embodiment, the outer needle 20 is pushed away from the inner needle 10 along the radial direction of the inner needle 10 by the first structural member 30, so that the effect of expanding the outer diameter of the winding needle 100 can be achieved, meanwhile, the first structural member 30 can be separated from the outer needle 20, at this time, under the action of tension in the winding process of the electrode assembly, the electrode assembly can apply pressure to the winding needle 100, so that the outer needle 20 can be close to the inner needle 10 along the radial direction of the inner needle 10, the effect of reducing the outer diameter of the winding needle 100 can be achieved, the outer diameter of the winding needle 100 can be increased or reduced, so that the outer diameter of the winding needle 100 can be adjusted in the winding process of the electrode assembly, different situations can be adapted, and the situation of dislocation of the tab can be relieved.

Referring to fig. 2 and 3, in some embodiments, the winding needle 100 further includes an elastic member 40 provided in the winding needle 100, one end of the elastic member 40 is connected to the outer needle 20, and the other end of the elastic member 40 can be connected to the inner needle 10 or the other outer needle 20, and the elastic member 40 is used to apply a force directed in the direction of the inner needle 10 to the outer needle 20.

The elastic member 40 is an elastic structure in the winding needle 100, the elastic member 40 may include a spring, a rubber strip or other elastic structures, and the material of the elastic member 40 may include metal, rubber or other elastic materials.

The elastic element 40 is disposed in the winding needle 100, that is, the elastic element 40 is disposed between at least two outer needles 20, the elastic element 40 is configured to apply a force directed toward the inner needle 10 to the outer needles 20, when the first structural member 30 moves and has a tendency to separate from the outer needles 20, the elastic element 40 can drive the outer needles 20 to move toward the inner needles 10 to approach the inner needles 10 and abut against the first structural member 30, and when the first structural member 30 moves leftwards, for example, as shown in fig. 3, the first structural member 30 has a tendency to separate from the outer needles 20, and at this time, the elastic element 40 can drive the outer needles 20 to move toward the inner needles 10 and can press the outer needles 20 against the first structural member 30.

The elastic member 40 is in a stretched state when the outer needle 20 moves in a direction away from the inner needle 10 and applies a force to the outer needle 20 toward the inner needle 10, and the elastic member 40 may be in a stretched state or in an unstressed natural state when the outer needle 20 is located at a position closest to the inner needle 10.

One end of the elastic member 40 is connected to the outer needle 20, the other end of the elastic member 40 may be connected to the inner needle 10, one end of the elastic member 40 may be connected to the outer needle 20, the other end of the elastic member 40 may be connected to another outer needle 20, the outer needle 20 may be connected to each outer needle 20 in case that there are three or more outer needles 20, since the plurality of outer needles 20 are disposed around the circumference of the inner needle 10, the force applied from the elastic member 40 to each outer needle 20 may intersect on the axis of the inner needle 10 in case that the elastic member 40 is connected to each outer needle 20, and the elastic member 40 may be connected to both the inner needle 10 and each outer needle 20, for example, the middle of the elastic member 40 is sleeved on the inner needle 10 and connected to each outer needle 20 at the edges, respectively.

Depending on the material of the elastic member 40, the elastic member 40 may be connected to the corresponding outer needle 20 and inner needle 10 by welding, gluing, or the like, or may be connected to the corresponding outer needle 20 and inner needle 10 by screwing, hooking, or the like.

The elastic member 40 is a rubber ring, and a hanging portion is disposed on one side of each outer needle 20 facing the inner needle 10, the hanging portion of each outer needle 20 is distributed along the circumferential side of the inner needle 10, at this time, the rubber ring surrounds all the hanging portions, each hanging portion can extend into the rubber ring and prop against the inner wall of the rubber ring, under the condition that the outer needle 20 moves in a direction away from the inner needle 10, the rubber ring is deformed, under the condition that the first structural member 30 has a tendency to separate from the outer needle 20, the rubber ring has a tendency to recover and makes each outer needle 20 move in a direction approaching to the inner needle 10, so as to press and hold the outer needle 20 on the first structural member 30, thereby achieving the effect of reducing the outer diameter of the winding needle 100.

In this embodiment, the elastic member 40 applies force to the outer needle 20 in the direction of the inner needle 10, so that the elastic member 40 can press the outer needle 20 against the first structural member 30, and the first structural member 30 can cooperate with the elastic member 40 to drive the outer needle 20 to move along the radial direction of the inner needle 10 toward or away from the inner needle 10, so that the winding needle 100 has the functions of expanding the outer diameter and shrinking the outer diameter, and the winding needle 100 does not need to rely on the pressure of winding an electrode assembly to realize the shrinking of the outer diameter, thereby facilitating the better reduction of the dislocation of tabs in the winding process of the electrode assembly.

Referring to fig. 2-5, in some embodiments, the first structure 30 includes a first bevel 31, the first bevel 31 being inclined relative to the axis of the inner needle 10 and forming a first angle with the axis of the inner needle 10, the first bevel 31 abutting the outer needle 20 such that the outer needle 20 is movable along the first bevel 31 relative to the first structure 30.

The first inclined plane 31 is an inclined plane arranged on the first structural member 30, the first inclined plane 31 is inclined relative to the axis of the inner needle 10, the first inclined plane 31 and the axis of the inner needle 10 can form a first included angle, namely an included angle shown as an angle a in fig. 4 and 5, the inclined directions of the first inclined plane 31 can be various, the inclined directions of the first inclined plane 31 are different, and the movement directions required by the first structural member 30 to push the outer needle 20 away from the inner needle 10 are also different.

For example, one end of the first inclined surface 31 faces the inside of the winding needle 100, the other end of the first inclined surface 31 may be inclined in a direction away from the axis of the inner needle 10 toward the outside of the winding needle 100, and the movement of the first structural member 30 toward the inside of the winding needle 100 may push the outer needle 20 to move away from the inner needle 10, and referring to fig. 4, the right end of the first inclined surface 31 faces the inside of the winding needle 100, and the left end of the first inclined surface 31 is inclined to the left and the upper side, and the movement of the first structural member 30 to the right may push the outer needle 20 to move upward along the first inclined surface 31 to move away from the inner needle 10.

For example, one end of the first inclined surface 31 faces the inside of the winding needle 100, the other end of the first inclined surface 31 may also incline in a direction toward the outside of the winding needle 100 and toward the axis of the inner needle 10, and at this time, the movement of the first structural member 30 toward the outside of the winding needle 100 may push the outer needle 20 to move away from the inner needle 10, and referring to fig. 5, the right end of the first inclined surface 31 faces the inside of the winding needle 100, and the left end of the first inclined surface 31 inclines downward and leftward, and at this time, the movement of the first structural member 30 leftward may push the outer needle 20 to move upward along the first inclined surface 31 to move away from the inner needle 10.

In this embodiment, the first structural member 30 includes the first inclined surface 31, and the first inclined surface 31 abuts against the outer needle 20, at this time, the first structural member 30 moves to push the outer needle 20 along the first inclined surface 31 to move away from the inner needle 10, and at the same time, under the action of the tension of the elastic member 40 or the electrode assembly, the outer needle 20 can also approach the inner needle 10 along the first inclined surface 31 when the first structural member 30 moves reversely, so that the outer diameter of the winding needle 100 can be enlarged or reduced.

Referring to fig. 2-5, in some embodiments, the first included angle may range from 40 ° to 50 °, for example, the first included angle may range from 40 °, 42 °, 44 °, 45 °, 46 °, 48 °, 50 °, or other values.

The first included angle is the included angle formed by the intersection of the first inclined surface 31 and the axis of the inner diameter, namely the included angle shown as the angle a in fig. 4 and 5.

The angle of the first included angle of the first inclined surface 31 can affect the relationship between the moving distance of the first structural member 30 and the moving distance of the outer needle 20, that is, the greater the angle of the first included angle, the greater the distance the outer needle 20 is pushed to move when the first structural member 30 moves by a unit distance.

The angle range of the first included angle is 40-50 degrees, so that the first structural member 30 can move quickly to drive the outer needle 20 to move on the radial Y of the inner needle 10, the outer diameter adjustment of the winding needle 100 can have quick response speed, the friction resistance between the first inclined surface 31 and the outer needle 20 is small, the friction loss is reduced, and the service life is prolonged.

For example, the angle of the first included angle may be 50 °, and at this time, the first structural member 30 may be moved by a smaller distance, i.e. may push the outer needle 20 to move by a larger distance, so that the movement of the first structural member 30 may quickly drive the outer needle 20 to move in the radial direction Y of the inner needle 10, thereby enabling the outer diameter adjustment of the winding needle 100 to have a faster response speed.

Illustratively, the angle of the first included angle may be 45 °, which may enable a faster response speed for outer diameter adjustment of the winding needle 100, and may also reduce friction between the outer needle 20 and the first bevel 31, thereby reducing friction losses.

For example, the angle of the first included angle may be 40 °, and the frictional resistance between the first inclined surface 31 and the outer needle 20 is smaller, and the frictional loss is lower.

In this embodiment, the included angle of the first inclined surface 31 limits the distance that the outer needle 20 can move along the radial direction of the inner needle 10, so that the first structural member 30 can move a short distance to adjust the change of the outer diameter of the winding needle 100, so that the adjustment of the outer diameter of the winding needle 100 can have a fast response speed, and meanwhile, the resistance between the first structural member 30 and the outer needle 20 can be reduced, thereby reducing the friction loss between the first structural member 30 and the outer needle 20 and prolonging the service life of the winding needle 100.

Referring to fig. 2-5, in some embodiments, the length of the first incline 31 ranges from 3mm to 5mm, and exemplary lengths of the first incline 31 may be 3mm, 3.5mm, 4mm, 4.5mm, 5mm, or other values.

The length of the first inclined plane 31 is the length of the first inclined plane 31 at the inclination angle, i.e. the dimension indicated by L1 in fig. 4 and 5.

The length of the first inclined surface 31 can affect the relationship between the moving distance of the first structural member 30 and the moving distance of the outer needle 20, i.e., the larger the length of the first inclined surface 31, the larger the maximum distance the outer needle 20 can move.

The length range of the first inclined surface 31 is 3 mm-5 mm, so that the first inclined surface 31 can meet the requirement of outer diameter size adjustment, and the size of the first structural member 30 can be reduced, and the space requirement of the first structural member 30 can be reduced.

For example, the length of the first inclined surface 31 may be 3mm, and the angle of the first included angle may be 50 °, and at this time, the first structural member 30 may be moved a small distance, i.e. may push the outer needle 20 to move a large distance, so that the first structural member 30 may move quickly to drive the outer needle 20 to move in the radial direction Y of the inner needle 10, so that the outer diameter adjustment of the winding needle 100 may have a quick response speed.

By way of example, the length of the first inclined surface 31 may be 4mm and the angle of the first included angle may be 45 °, which may enable the outer diameter adjustment of the winding needle 100 to have a faster response speed and may also reduce the friction between the outer needle 20 and the first inclined surface 31, thereby reducing friction loss.

For example, the length of the first inclined surface 31 may be 5mm, and the angle of the first included angle may be 40 °, at which time the friction resistance between the first inclined surface 31 and the outer needle 20 is smaller and the friction loss is lower.

The technical solution of this embodiment provides a range of lengths of the first inclined planes 31, so that the distance that the outer needle 20 can move along the radial direction of the inner needle 10 is limited by the length of the first inclined planes 31, thereby limiting the range of variation of the outer diameter of the winding needle 100, and reducing the occurrence of dislocation of tabs in the winding process of the electrode assembly.

Referring to fig. 2 to 6, in some embodiments, the winding needle 100 further includes a second structural member 51, the second structural member 51 and the first structural member 30 are respectively disposed at opposite ends of the inner needle 10 along the axial direction of the inner needle 10, the second structural member 51 is abutted against the outer needle 20 at least along the axial direction of the inner needle 10, and the first structural member 30 is capable of moving relative to the second structural member 51 along the axial direction of the inner needle 10.

The second structural member 51 refers to a structure of the winding needle 100 for supporting the outer needle 20 in cooperation with the first structural member 30, the second structural member 51 may be connected to the inner needle 10 or connected to other structures of the winding needle 100, the second structural member 51 may be a separate member, the second structural member 51 may be a rod-shaped structure or a block-shaped structure or a structure with other shapes, and the material of the second structural member 51 may include plastics, metals or other materials.

The second structural members 51 are abutted against the outer needles 20, and therefore, at least two outer needles 20 are arranged, and only one second structural member 51 can be abutted against each outer needle 20, two or more second structural members 51 can be arranged, so that each outer needle 20 can correspond to at least one second structural member 51, and in the condition that the second structural members 51 are matched with the first structural members 30, at least two supported parts are arranged on each outer needle 20, so that the outer needles 20 can move along the radial direction of the inner needle 10 relatively stably.

The second structural member 51 abuts the outer needle 20 at least in the axial direction X of the inner needle 10, i.e. the second structural member 51 is capable of exerting at least one force on the outer needle 20 in the axial direction X of the inner needle 10 and directed towards the outer needle 20, which force is capable of balancing the force exerted by the first inclined surface 31 on the outer needle 20 by the first inclined surface 31 in parallel to the axial direction X of the inner needle 10 and limiting the movement of the second structural member 51 in the axial direction X of the inner needle 10 in order to allow a better movement of the outer needle 20 in the radial direction Y of the inner needle 10 in case the first structural member 30 moves in the axial direction X of the inner needle 10 and pushes the outer needle 20.

The first structural member 30 and the second structural member 51 are respectively located at two ends of the inner needle 10 along the axial direction X of the inner needle 10, so that the first structural member 30 and the second structural member 51 respectively support two opposite sides of the outer needle 20, thereby better improving the stability of the outer needle 20 in the moving process and reducing the occurrence of skew and other conditions.

The first structural member 30 is movable relative to the second structural member 51 along the axial direction X of the inner needle 10, and the second structural member 51 may be fixed relative to the winding needle 100 or movable relative to the winding needle 100 on the basis that the first structural member 30 is movable.

In this embodiment, the first structural member 30 and the second structural member 51 are disposed at two ends of the inner needle 10, and the first structural member 30 and the second structural member 51 can respectively abut against two ends of the outer needle 20, and in the process that the first structural member 30 moves and pushes the outer needle 20 to move along the radial direction of the inner needle 10, the outer needle 20 can always abut against the second structural member 51, so that the second structural member 51 cooperates with the first structural member 30 to support the outer needle 20 together, thereby increasing stability of the outer needle 20 in the moving process, and reducing skew and other situations of the outer needle 20 in the moving process.

Referring to fig. 2-6, in some embodiments, the second structure 51 includes a second bevel 511, the second bevel 511 abutting against the outer needle 20, the second bevel 511 forming a second angle with the axis of the inner needle 10, and a projection of the plane of the second bevel 511 intersecting the plane of the first bevel 31 along the radial direction Y of the inner needle 10 being in a central region of the inner needle 10.

The second inclined plane 511 is an inclined plane disposed on the second structural member 51, and the second inclined plane 511 and the axis of the inner needle 10 can form a second included angle, that is, the second inclined plane 511 is inclined relative to the axis of the inner needle 10, and the second included angle is an included angle shown as an angle a in fig. 4 and 5.

The intersection of the plane where the second inclined plane 511 is located and the plane where the first inclined plane 31 is located means that the second inclined plane 511 is not parallel to the first inclined plane 31, and the projection of the intersection of the second inclined plane 511 and the first inclined plane 31 along the radial direction Y of the inner needle 10 is located in the middle area of the inner needle 10, namely, the inclined direction of the first inclined plane 31 is opposite to the inclined direction of the second inclined plane 511, and the middle area of the inner needle 10 is the area between the first structural member 30 and the second structural member 51 along the axial direction X of the inner needle 10.

In this embodiment, the second inclined plane 511 is disposed on the second structural member 51, and the intersection of the second inclined plane 511 and the first inclined plane 31 is located in the middle area of the inner needle 10, so that the inclined directions of the first inclined plane 31 and the second inclined plane 511 are opposite, and in the process of moving the first structural member 30 and pushing the outer needle 20, the outer needle 20 can be always abutted against the second inclined plane 511 and move along the second inclined plane 511, so that the outer needle 20 is supported by the second inclined plane 511, and the stability of the movement of the outer needle 20 is improved.

Referring to fig. 2-6, in some embodiments, the second included angle is equal to the first included angle.

The second angle being equal to the first angle means that the inclination angles of the second inclined plane 511 and the first inclined plane 31 are the same, and the first structural member 30 and the second structural member 51 are both abutted against the outer needle 20, so that when one end of the outer needle 20 abutted against the first inclined plane 31 moves along the first inclined plane 31, one end of the outer needle 20 abutted against the second inclined plane 511 can synchronously move along the second inclined plane 511, and the outer needle 20 can be relatively stable and not easy to skew in the moving process, thereby being convenient for providing support for the electrode assembly and reducing the abnormal conditions such as deformation and the like of the electrode assembly in the winding process.

The second inclined surface 511 can provide a force parallel to the axial direction X of the inner needle 10 to the outer needle 20, which can limit the movement of the outer needle 20 in the axial direction X of the inner needle 10, and at the same time, the second inclined surface 511 can provide a force parallel to the radial direction Y of the inner needle 10 to the outer needle 20, which can play a role in supporting and supporting the outer needle 20, thereby further reducing the occurrence of skew of the outer needle 20 during the movement and improving the stability of the movement of the outer needle 20.

For example, one end of the first inclined surface 31 faces the inside of the winding needle 100, the other end of the first inclined surface 31 may be inclined in a direction facing the outside of the winding needle 100 and away from the axis of the inner needle 10, while one end of the second inclined surface 511 faces the inside of the winding needle 100, the other end of the second inclined surface 511 may be inclined in a direction facing the outside of the winding needle 100 and away from the axis of the inner needle 10, while the first structural member 30 moves closer to the second structural member 51 to push the outer needle 20 more smoothly away from the inner needle 10, referring to fig. 4 and 6, the right end of the first inclined surface 31 faces the inside of the winding needle 100, the left end of the first inclined surface 31 is inclined to the left and the left end of the second inclined surface 511 faces the inside of the winding needle 100, and the right end of the second inclined surface 511 is inclined to the right and upward, while the first structural member 30 moves rightward to push the outer needle 20 more stably upward along the first inclined surface 31 and the second inclined surface 511 to move away from the inner needle 10.

In this embodiment, the inclination angle of the second inclined plane 511 is the same as that of the first inclined plane 31, so that the outer needle 20 can always abut against the second inclined plane 511 and move along the second inclined plane 511 in the process of moving the first structural member 30 and pushing the outer needle 20, so as to support the outer needle 20 through the second inclined plane 511, thereby further improving the stability of the movement of the outer needle 20 and reducing the occurrence of skew and the like of the outer needle 20 in the movement process.

Referring to fig. 2 to 6, in some embodiments, two third structural members 221 are disposed on the outer needle 20, and the two third structural members 221 are disposed at two ends of the outer needle 20 along the axial direction of the inner needle 10, where the two third structural members 221 respectively abut against the first structural member 30 and the second structural member 51.

The third structural member 221 refers to a structure on the outer needle 20 for abutting against the first structural member 30, the third structural member 221 may be fixedly connected to the outer needle 20 by welding, bonding, integral molding or other methods, or may be detachably connected to the outer needle 20 by screwing, clamping or other methods, the third structural member 221 may be a rod-shaped structure, a block-shaped structure or other structures, and the material of the third structural member 221 may include plastics, metals or other materials.

Two third structural members 221 are disposed at two ends of the outer needle 20 along the axial direction X of the inner needle 10, and in an example, two third structural members 221 may be disposed at two ends of the outer needle 20 along the axial direction X of the inner needle 10, and two third structural members 221 may also be disposed at one side of the two ends of the outer needle 20 facing the inner needle 10, and in an example, the third structural members 221 are disposed at one side of the outer needle 20 facing the inner needle 10, i.e., the third structural members 221 are disposed inside the winding needle 100, so that one side of the outer needle 20 facing the outside can be smoother, thereby reducing damage to the electrode assembly during winding of the electrode assembly around the winding needle 100.

In the case that the winding needle 100 includes the first structural member 30 and the second structural member 51, and the first structural member 30 and the second structural member 51 are respectively located at two opposite ends of the inner needle 10 along the axial direction X thereof, the two third structural members 221 are respectively located at two ends of the outer needle 20 along the axial direction X of the inner needle 10, so that the two third structural members 221 can be respectively abutted against the first structural member 30 and the second structural member 51, and at this time, the outer needle 20 has two supporting portions, so that the outer needle 20 can move relatively stably, and situations such as skew are not easy to occur.

In this embodiment, two third structural members 221 are disposed on the outer needle 20 and respectively support against the first structural member 30 and the second structural member 51, so that the first structural member 30 and the second structural member 51 can support the outer needle 20 through the third structural member 221, thereby increasing the stability of the outer needle 20 in the moving process and reducing the occurrence of skew and the like of the outer needle 20 in the moving process.

Referring to fig. 2-6, in some embodiments, each of the two third structures 221 includes a third ramp 2211, one of the two third ramps 2211 is parallel to the adjacent first ramp 31 and abuts the first ramp 31, and the other of the two third ramps 2211 is parallel to the adjacent second ramp 511 and abuts the second ramp 511.

The third inclined surface 2211 is an inclined surface provided on the third structural member 221, the third inclined surface 2211 is parallel to the first inclined surface 31, and the third inclined surface 2211 abuts against the first inclined surface 31, so that the first structural member 30 moves along the axial direction X of the inner needle 10, and the outer needle 20 can be pushed to move along the radial direction Y of the inner needle 10 by the first inclined surface 31 and the third inclined surface 2211.

For example, one ends of the first inclined surface 31 and the third inclined surface 2211 may each face the inside of the winding needle 100, the other ends of the first inclined surface 31 and the third inclined surface 2211 may each be inclined in a direction toward the outside of the winding needle 100 away from the axis of the inner needle 10, and referring to fig. 4, the right ends of the first inclined surface 31 and the third inclined surface 2211 each face the inside of the winding needle 100, and the left ends of the first inclined surface 31 and the third inclined surface 2211 each are inclined to the upper left, at which time the first structural member 30 moves rightward to push the outer needle 20 upward along the first inclined surface 31 to be away from the inner needle 10.

For example, one end of the first inclined surface 31 and one end of the third inclined surface 2211 face the inside of the winding needle 100, the other end of the first inclined surface 31 and the other end of the third inclined surface 2211 can also incline in a direction toward the outside of the winding needle 100 and close to the axis of the inner needle 10, referring to fig. 5, the right end of the first inclined surface 31 and the right end of the third inclined surface 2211 face the inside of the winding needle 100, and the left end of the first inclined surface 31 and the left end of the third inclined surface 2211 incline downward and leftward, at this time, the first structural member 30 moves leftward and can push the outer needle 20 to move upward along the first inclined surface 31 to be far away from the inner needle 10.

The third inclined surface 2211 of one adjacent to the first structural member 30 of the two third structural members 221 is parallel to the adjacent first inclined surface 31, the third inclined surface 2211 is abutted against the first inclined surface 31 and is in surface contact with the first inclined surface 31, the third inclined surface 2211 of the other adjacent to the second structural member 51 of the two third structural members 221 is parallel to the adjacent second inclined surface 511, the third inclined surface 2211 is abutted against the second inclined surface 511 and is in surface contact with the second inclined surface 511, and the arrangement enables the two third structural members 221 to be in surface contact with the first structural member 30 and the second structural member 51, so that the stability of movement of the third structural member 221 relative to the first structural member 30 and the second structural member 51 is further improved, the movement stability of the outer needle 20 is further improved, and the conditions of skew and the like of the outer needle 20 are reduced.

Meanwhile, the surface contact of the third structural member 221 with the first structural member 30 and the second structural member 51 can reduce the stress concentration at the contact part, so that the damage of the first structural member 30, the second structural member 51 and the third structural member 221 is reduced, and the service life of the winding needle 100 is prolonged.

In this embodiment, the third inclined surface 2211 is disposed on the third structural member 221, and the two third inclined surfaces 2211 are respectively parallel to the adjacent first inclined surfaces 31 or second inclined surfaces 511, so that the third structural member 221 is in surface contact with the first structural member 30 and the second structural member 51, so that the stability of contact between the third structural member 221 and the first structural member 30 and between the third structural member 221 and the second structural member 51 can be increased, the stability of the outer needle 20 in the moving process can be further increased, and the situation that the outer needle 20 is askew in the moving process can be reduced.

Referring to fig. 2 and 3, in some embodiments, the first structure 30 is fixedly connected to the inner needle 10, and the winding needle 100 further comprises a driving assembly 60, wherein the driving assembly 60 is used for driving the inner needle 10 to move along the axial direction of the inner needle 10 so as to push the outer needle 20 away from the inner needle 10 along the radial direction of the inner needle 10 through the first structure 30.

The driving component 60 refers to a structure in the winding needle 100 for driving the inner needle 10 to move, and the driving component 60 can comprise a cylinder, an electric telescopic cylinder or other linear feeding structures, and also can comprise a gear rack structure matched with a motor, a crank block structure matched with a motor or other structures.

The driving unit 60 may be disposed inside the winding needle 100 or outside the winding needle 100, and the driving unit 60 is disposed at one side outside the winding needle 100 in the axial direction of the inner needle 10, for example.

The first structural member 30 is fixedly connected to the inner needle 10, so that the driving assembly 60 drives the inner needle 10 to move and can drive the first structural member 30 to move synchronously, and the driving assembly 60 can be arranged outside the winding needle 100 instead of inside the winding needle 100 due to the fact that the size of the winding needle 100 is usually smaller, so that the arrangement difficulty of the driving assembly 60 is reduced, and the requirement on the internal space of the winding needle 100 can be reduced.

In this embodiment, the driving assembly 60 drives the inner needle 10 to move, and the inner needle 10 drives the first structural member 30 to move, so that the first structural member 30 can push the outer needle 20 to move, thereby achieving the effect of adjusting the outer diameter of the winding needle 100.

Referring to fig. 2 and 3, in some embodiments, the outer needles 20 are provided with air inlets 211, at least two outer needles 20 can enclose an air flow space 201, the air flow space 201 is communicated with the air inlets 211, and the air flow space 201 is used for being communicated with an air suction device so as to form negative pressure in the air flow space 201.

The air inlet 211 is a hole structure formed on the outer needle 20, air outside the winding needle 100 can enter the winding needle 100 through the air inlet 211, the air inlet 211 can be a square hole, a round hole or a hole structure with other shapes, the air inlet 211 can be a straight hole, a stepped hole, a conical hole or a hole structure with other shapes, one air inlet 211 can be provided, two or more air inlets 211 can be provided, and a plurality of air inlets 211 can be uniformly arranged on the outer needle 20 in an array mode under the condition that two or more air inlets 211 are provided, or the air inlets 211 can be irregularly arranged on the outer needle 20.

At least two outer needles 20 can enclose an air flow space 201, the inner needle 10 is positioned in the air flow space 201, the air flow space 201 can be a cylindrical space, a prismatic space or other shaped space according to the shape of the outer needles 20, and the air flow space 201 is communicated with an air inlet 211 so that air outside the winding needle 100 can enter the air flow space 201 through the air inlet 211.

The airflow space 201 is used to connect with an air extractor, which is a structure for extracting the air in the airflow space 201 out of the winding needle 100, and the air extractor may include a blower, a vacuum pump, or other structures capable of transmitting the air.

The air extraction device can be arranged in the air flow space 201 or outside the winding needle 100, and the air extraction device is arranged outside the winding needle 100 by way of example.

The air extracting device can extract the air in the air flow space 201 out of the winding needle 100 and form negative pressure in the air flow space 201, can extract the air out of the winding needle 100 into the air flow space 201 from the air inlet 211 and extract the air in the air flow space 201 out of the winding needle 100 under the condition that the electrode assembly is not covered on the winding needle 100, and can absorb the contact part of the electrode assembly and the winding needle 100 on the outer needle 20 under the condition that the electrode assembly covers at least part of the winding needle 100, so as to fix the corresponding part of the electrode assembly.

It will be appreciated that the movement of the outer needles 20 in the radial direction Y of the inner needle 10 may cause gaps between adjacent outer needles 20, but because the outer diameter of the winding needle 100 is smaller, the movement distance of the outer needles 20 is smaller, and the gaps between adjacent outer needles 20 are smaller, the winding needle 100 can still better absorb the electrode assembly on the winding needle 100 by increasing the power of the air extractor, and meanwhile, because the electrode assembly is wound, the electrode assembly can cover most of the gaps between the adjacent outer needles 20, thereby further reducing the damage of the negative pressure.

In this embodiment, the air extracting device can extract the air in the air flow space 201 out of the winding needle 100 to form a negative pressure in the air flow space 201, and the negative pressure in the air flow space 201 can adsorb the electrode assembly near the air inlet 211 on the outer needle 20 to achieve the effect of fixing the electrode assembly.

Referring to fig. 2 and 3, in some embodiments, there are at least two air intake holes 211, and the at least two air intake holes 211 are uniformly arranged on the outer needle 20.

There are at least two air intake holes 211, i.e., the number of air intake holes 211 may be two, or three or more.

Under the condition that the electrode assembly is adsorbed on the winding needle 100 under the action of negative pressure, the main stress part of the electrode assembly is a part close to the air inlet hole 211, so that the air inlet hole 211 is uniformly distributed on the outer needle 20, the stress of the electrode assembly is more uniform, the deformation and other conditions possibly caused by the concentrated local stress of the electrode assembly can be reduced, the electrode assembly can be better adsorbed and attached on the outer needle 20, and the occurrence of turnover and other conditions caused by the insufficient local stress of the electrode assembly is reduced.

In this embodiment, at least two air inlets 211 are provided, so that the outer needle 20 can have at least two positions for adsorbing the electrode assembly, thereby improving the stability of fixing the electrode assembly and improving the fixing effect, and at least two air inlets 211 are uniformly arranged, so that the adsorption force applied to the electrode assembly can be relatively uniform, and thus reducing the deformation and other anomalies possibly caused by uneven stress of the electrode assembly.

Referring to fig. 2 and 3, in some embodiments, the aperture of the air intake aperture 211 ranges from 1mm (millimeter) to 2mm, and exemplary apertures of the air intake aperture 211 may be 1mm, 1.2mm, 1.4mm, 1.5mm, 1.6mm, 1.8mm, 2mm, or other values.

The aperture of the air inlet hole 211 is the diameter of the air inlet hole 211, and the dimension shown by R in the figure refers to the aperture of the air inlet hole 211 in fig. 3. The aperture of the air inlet hole 211 is in the range of 1 mm-2 mm, so that the negative pressure in the air flow space 201 can adsorb the electrode assembly near the air inlet hole 211, and the partial deformation of the electrode assembly or the diaphragm is not easy to cause and enter the air inlet hole 211, thereby reducing the damage to the electrode assembly.

The distance between two adjacent air inlets 211 is 2 mm-4 mm, and the distance between two adjacent air inlets 211 may be 2mm, 2.5mm, 3mm, 3.5mm, 4mm or other values, for example.

The distance between the centers of the adjacent two air inlets 211 is set to be the distance between the centers of the adjacent two air inlets 211, and referring to fig. 3, the dimension shown by W in the figure is the distance between the adjacent two air inlets 211, and because the strength of the suction force of the negative pressure in the air flow space 201 to the electrode assembly is related to the total area of each air inlet 211, the distance between the adjacent two air inlets 211 is in the range of 2 mm-4 mm, not only can the electrode assembly be better adsorbed on the outer needle 20, but also the outer needle 20 can have a certain strength, so that the negative influence of the air inlets 211 on the strength of the outer needle 20 can be reduced, and meanwhile, the outer needle 20 can better provide support for the electrode assembly.

For example, the apertures of the air inlet holes 211 may be 1mm, the distance between two adjacent air inlet holes 211 may be 2mm, the apertures of the air inlet holes 211 are smaller, the adsorption force to the electrode assembly is smaller at the position of a single air inlet hole 211, the electrode assembly is less prone to deformation, and the number of air inlet holes 211 is larger at the same time, so that the electrode assembly is adsorbed on the outer needle 20.

By way of example, the aperture of the air inlet hole 211 may be 1.5mm, the distance between two adjacent air inlet holes 211 may be 3mm, the aperture of the air inlet hole 211 is increased at this time, the adsorption force to the electrode assembly is increased at the position of a single air inlet hole 211, the electrode assembly is not easy to deform, and the electrode assembly can be better adsorbed.

For example, the hole diameter of the air inlet hole 211 may be 2mm, the interval between two adjacent air inlet holes 211 may be 4mm, and at this time, the hole diameter of the air inlet hole 211 is larger, and the adsorption force to the electrode assembly is larger at the position of the single air inlet hole 211, so that the electrode assembly can be better adsorbed.

The present embodiment provides a range of aperture and a range of spacing of the air intake holes 211, so that the air intake holes 211 can not only absorb the electrode assembly more stably, but also reduce the occurrence of deformation of the electrode assembly caused by the entering of the electrode assembly or the separator into the air intake holes 211.

In some embodiments, the negative pressure ranges from-50 KPa to-75 KPa, and illustratively, the negative pressure may range from-50 KPa, -505KPa, -60KPa, -65KPa, -70KPa, -75KPa, or other values.

Because the air pressure outside the winding needle 100 is normal atmospheric pressure, the larger the absolute value of the negative pressure is, the better the adsorption performance of the winding needle 100 to the electrode assembly is, and the negative pressure is in the range of-50 KPa to-75 KPa, so that the winding needle 100 can stably adsorb the electrode assembly and can reduce the deformation of the electrode assembly caused by the electrode assembly or the diaphragm entering the air inlet 211.

For example, the negative pressure in the airflow space 201 may be-50 KPa, and the winding needle 100 may not only reduce deformation of the electrode assembly, but also stably adsorb the electrode assembly.

For example, the negative pressure in the airflow space 201 may be-62.5 KPa, and the winding needle 100 may not only reduce deformation of the electrode assembly, but also adsorb the electrode assembly more stably.

For example, the negative pressure in the air flow space 201 may be-50 KPa, and the winding needle 100 can not only absorb the electrode assembly more stably, but also reduce the deformation of the electrode assembly.

The present embodiment provides a range of negative pressure in the airflow space 201, so that the winding needle 100 can not only absorb the electrode assembly more stably, but also reduce the occurrence of deformation of the electrode assembly caused by the electrode assembly or the separator entering the air inlet hole 211.

Referring to fig. 2 and 3, in some embodiments, the inner needle 10 is provided with an airflow channel 101 in communication with the airflow space 201, and one end of the airflow channel 101 is used to communicate with an air extractor, so as to extract the air in the airflow space 201 out of the winding needle 100 through the airflow channel 101.

The air flow channel 101 is a channel structure arranged inside the inner needle 10, the air flow channel 101 can be formed by a pipe fitting embedded in the inner needle 10 or can be directly formed by arranging a hole structure in the inner needle 10, the air flow channel 101 can be of a linear structure or a bending structure, and the cross section of the air flow channel 101 can be square, circular or other shapes along the radial direction of the air flow channel 101.

The air flow channel 101 is communicated with the air flow space 201, one end of the air flow channel 101 is communicated with the air extracting device, so that the air extracting device can draw air in the air flow space 201 into the air flow channel 101 and extract the air in the air flow channel 101 out of the winding needle 100, one end of the air flow channel 101 away from the air extracting device can be directly communicated with the air flow space 201, or one or more through holes can be formed in the side wall of the inner needle 10 facing the outer needle 20, so that the air flow channel 101 is communicated with the air flow space 201 through the through holes.

In this embodiment, the air flow channel 101 is formed in the inner needle 10, so that the air extractor can extract the air in the air flow space 201 through the air flow channel 101 and form negative pressure, thereby facilitating the air extractor to extract the air from the air flow space 201, and the arrangement can also reduce the occupation of the air flow channel 101 to the inner space of the winding needle 100 due to the generally smaller overall size of the winding needle 100, thereby reducing the difficulty in arranging each structure in the winding needle 100 and saving space.

Referring to fig. 2 and 3, in some embodiments, the outer needle 20 includes a middle portion 21, two ends of the middle portion 21 along the axial direction of the inner needle 10 are connected with end portions 22, the end portions 22 are abutted against the first structural member 30, the air inlet hole 211 is at least formed on the middle portion 21, and the air flow space 201 is at least formed between the middle portions 21 of different outer needles 20.

The intermediate portion 21 and the end portion 22 are respectively part of the structure of the outer needle 20, and the end portion 22 is provided at both ends of the intermediate portion 21 in the axial direction X of the inner needle 10.

The middle portion 21 may be an arc-shaped sheet structure, a plane sheet structure or other shape structure according to the shape of the winding needle 100, and the material of the middle portion 21 may include metal, plastic or other materials.

Since the end portions 22 are disposed at both ends of the intermediate portion 21 and are mainly used to abut against the first structural member 30 and the second structural member 51, the electrode assembly is mainly in contact with the intermediate portion 21 during winding, and accordingly the shape of the end portions 22 may be the same as or similar to that of the intermediate portion 21 or may be different from that of the intermediate portion 21, and in order to reduce damage to the electrode assembly, the end portions 22 and the side walls of the intermediate portion 21 facing outward of the winding needle 100 are formed in the same shape, and in the case that the end portions 22 are connected to the intermediate portion 21, the arrangement can reduce misalignment of the side walls of the end portions 22 and the side walls of the intermediate portion 21 at the connection portions therebetween, thereby reducing damage to the electrode assembly.

The end 22 may be detachably connected to the middle portion 21 by screwing, clamping, or the like, or may be fixedly connected to the middle portion 21 by welding, bonding, or integrally molding, or the like, and the material of the end 22 may include metal, plastic, or other materials, and the material of the end 22 may be the same as the material of the middle portion 21, or may be different from the material of the middle portion 21.

The air inlet hole 211 is formed at least in the middle part 21, namely, the air inlet hole 211 can be formed only in the middle part 21, the air inlet hole 211 can be formed in both the middle part 21 and the end part 22, and the air flow space 201 is formed at least between the middle parts 21 of different outer needles 20, namely, the air flow space 201 can be formed only between the middle parts 21 of different outer needles 20, and can be formed between the middle parts 21 and the end parts 22 of different outer needles 20.

In this embodiment, the outer needle 20 includes a middle portion 21 and an end plate so that the end 22 can abut against the first structural member 30 to facilitate the first structural member 30 to push the outer needle 20 to move, and the air inlet hole 211 is opened on the middle portion 21 to facilitate the fixing of the electrode assembly by the winding needle 100 near the middle portion 21 so that the electrode assembly can be more stably fixed by the winding needle 100.

In some embodiments, the thickness of the intermediate portion 21 ranges from 5mm to 8mm, and exemplary thicknesses of the intermediate portion 21 may be 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, or other values.

The thickness of the middle part 21 is the dimension of the middle part 21 in the radial direction Y of the inner needle 10, and the middle part 21 is mainly used for providing support for the electrode assembly in the process of winding the electrode assembly, so that the thickness of the middle part 21 is in the range of 5 mm-8 mm, the middle part 21 can have stronger strength, the occupation of space can be reduced, the air flow can be smoothly extracted out of the winding needle 100 from the air flow space 201, and the weight of the outer needle 20 can be reduced.

For example, the thickness of the middle portion 21 may be 5mm, at which time the thickness of the middle portion 21 is thinner, the overall thickness of the winding needle 100 is lighter, and the air flow space 201 is larger, so that the negative pressure formed by the air suction device can better adsorb the electrode assembly at each air inlet hole 211.

For example, the thickness of the middle portion 21 may be 6.5mm, and at this time, the thickness of the middle portion 21 is increased, the strength of the winding needle 100 is increased, and the middle portion 21 has both stronger strength and better ability to absorb the electrode assembly.

By way of example, the thickness of the middle portion 21 may be 8mm, in which case the thickness of the middle portion 21 is thicker and the strength of the winding needle 100 is stronger, so as to better provide support for the electrode assembly wound around the winding needle 100.

In some embodiments, the end 22 is detachably connected to the middle portion 21, and the end 22 may be detachably connected to the middle portion 21 by screwing, clamping or other means, and by way of example, the end 22 is connected to the middle portion 21 by a bolt, and the bolt connection portion of the end 22 and the middle portion 21 may be located on the side of the outer needle 20 facing the inner needle 10, so as to reduce damage to the electrode assembly by the outer needle 20 during the winding of the electrode assembly.

Because the end portion 22 abuts against the first structural member 30 and the second structural member 51, the outer diameter of the winding needle 100 may be frequently changed during the winding process of the winding needle 100, in which case the end portion 22 is easily worn faster than the middle portion 21, and the end portion 22 is detachably connected to the middle portion 21, so that the installation, replacement and maintenance of the end portion 22 are facilitated, the maintenance cost of the winding needle 100 is reduced, and the overall assembly of the winding needle 100 is facilitated.

In some embodiments, a lower trough 23 is also formed on the circumferential side of the outer needle 20, and at least one end of the lower trough 23 is communicated with a space outside the winding needle 100 in the axial direction of the inner needle 10.

The blanking groove 23 is a groove structure on the winding needle 100 for accommodating the material taking device, the blanking groove 23 is arranged on the peripheral side surface of the outer needle 20, namely, an opening of the blanking groove 23 faces to the outside of the winding needle 100, after the electrode assembly is wound on the outer needle 20, the electrode assembly can seal the opening of the blanking groove 23, the length direction of the blanking groove 23 can be parallel to the axial direction X of the inner needle 10 or can be arranged at an included angle with the axial direction X of the inner needle 10, at least one end of the blanking groove 23 along the axial direction X of the inner needle 10 is communicated with a space outside the winding needle 100 so that the material taking device can enter the blanking groove 23, and the section shape of the blanking groove 23 along the depth direction of the blanking groove 23 can be square, semicircular, trapezoid or other shapes.

In such a winding needle 100, the material taking device can be moved in the direction away from the axis of the inner needle 10 into the lower chute 23 along the axial direction X of the inner needle 10, and can be moved from the opening of the lower chute 23 to the outside of the winding needle 100 to attach the electrode assembly, and after the electrode assembly is attached, the material taking device can be continuously moved in the direction away from the axis of the inner needle 10 and separate the electrode assembly from the outer needle 20 so as to remove the electrode assembly from the outer needle 20.

In the case where the outer needle 20 is formed by splicing the end portion 22 and the intermediate portion 21, a partial structure of the blanking groove 23 may be provided on each of the end portion 22 and the intermediate portion 21 so as to splice to form the complete blanking groove 23 after the end portion 22 is mounted on the intermediate portion 21.

Since the winding needle 100 includes at least two outer needles 20, only one lower feed groove 23 may be provided on each outer needle 20, or two or more lower feed grooves 23 may be provided.

In this embodiment, a discharging groove 23 is provided on the outer needle 20, so that the discharging device is easily introduced into the wound electrode assembly and removed from the winding needle 100.

Referring to fig. 1-6, in some embodiments, a winding needle 100 includes an inner needle 10, an outer needle 20, and a second structural member 51.

The two outer needles 20 are circumferentially arranged on the circumferential side of the inner needle 10 along the circumferential direction of the inner needle 10, the two outer needles 20 can move close to or away from the inner needle 10, the two outer needles 20 can mutually attach and splice to form a cylindrical structure when moving close to the inner needle 10, and an airflow space 201 is formed between the two outer needles 20.

The outer needle 20 comprises a middle part 21 and end parts 22 arranged at two ends of the middle part 21 along the axial direction X of the inner needle 10, a third structural part 221 is arranged on the end parts 22, a third inclined surface 2211 is arranged on the third structural part 221, a plurality of air inlet holes 211 which are uniformly arranged in an array are arranged on the middle part 21, and the air inlet holes 211 are communicated with the air flow space 201.

The side of the outer needle 20 facing the inner needle 10 is provided with hanging parts, and the elastic piece 40 is a rubber ring and surrounds the outside of all the hanging parts, namely, the hanging parts can extend into the rubber ring and prop against the inner wall of the rubber ring.

The inner needle 10 is provided with a first structural member 30, the first structural member 30 is provided with a first inclined surface 31, the first inclined surface 31 is abutted against the third inclined surface 2211, the inner needle 10 can move along the axial direction X of the inner needle, the inner needle 10 is internally provided with an air flow channel 101 along the axial direction X of the inner needle, the air flow channel 101 is communicated with the air flow space 201 through a through hole formed in the inner needle 10, and one end of the air flow channel 101 can extend out of the winding needle 100.

The second structural member 51 is provided with a second inclined surface 511, and the second inclined surface 511 abuts against another third inclined surface 2211.

The second structural member 51 is an independent member, the second structural member 51 is arranged on the base 50, the base 50 is arranged on one side of the winding needle 100 along the axial direction X of the inner needle 10, the second structural member 51 is arranged on the base 50, the inner needle 10 can move relative to the base 50 along the axial direction X of the inner needle, the base 50 is provided with a driving assembly 60 connected with the inner needle 10, and the driving assembly 60 can drive the inner needle 10 to move along the axial direction X of the inner needle.

The base 50 is also provided with a cavity 52, one end of the inner needle 10 extends into the cavity 52 and is communicated with the cavity 52, one end of the inner needle 10 is not easy to deviate from the cavity 52 due to the movement of the inner needle 10 along the axial direction X, the base 50 is also provided with a connector 53 communicated with the cavity 52, and an external air extractor can be communicated with the connector 53.

The movement of the inner needle 10 in the direction approaching the base 50 can push the outer needle 20 to move away from the inner needle 10 in the radial direction Y of the inner needle 10 through the first inclined surface 31, the second inclined surface 511 and the third inclined surface 2211 and deform the elastic member 40, and the movement of the inner needle 10 in the direction approaching the base 50 can make the first inclined surface 31 and the second inclined surface 511 have a tendency to separate from the corresponding third inclined surface 2211, at this time, the third inclined surface 2211 is abutted against the corresponding first inclined surface 31 or the second inclined surface 511 under the action of the elastic member 40 and makes the outer needle 20 move close to the inner needle 10 in the radial direction Y of the inner needle 10.

The external air extractor is started to pump the air in the air flow space 201 into the air flow channel 101 through the through hole, the air in the air flow channel 101 is pumped into the air extractor through the cavity 52 and the interface 53 and finally discharged to the space outside the winding needle 100, so that negative pressure is formed in the air flow space 201, and when the electrode assembly is positioned near the winding needle 100, the negative pressure can adsorb and fix the part of the electrode assembly near the winding needle 100 on the external needle 20, so that the winding of the electrode assembly is facilitated, and slipping and the like in the winding process of the electrode assembly are reduced.

In a second aspect, some embodiments of the present application further provide a winding apparatus, including the winding needle 100 provided in some embodiments of the first aspect, where the tab in the electrode assembly formed by winding with the winding apparatus is not easy to be misplaced, so as to alleviate situations of reduced service life, reduced capacity, safety risk, and the like of the battery, which may be caused by misplacement of the tab.

It should be noted that the above embodiments are only used to illustrate the technical solution of the present application, but not to limit the technical solution of the present application, and although the detailed description of the present application is given with reference to the above embodiments, it should be understood by those skilled in the art that the technical solution described in the above embodiments may be modified or some or all technical features may be equivalently replaced, and these modifications or substitutions do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present application, and all the modifications or substitutions are included in the scope of the claims and the specification of the present application. In particular, the technical features mentioned in the respective embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims (21)

1. A winding needle, comprising:

an inner needle;

at least two outer needles surrounding the inner needle in the circumferential direction of the inner needle, the outer needles being movably provided on the inner needle circumferential side in the radial direction of the inner needle;

The first structural member is propped against the outer needle and can move relative to the outer needle along the axial direction of the inner needle so as to push the outer needle to be far away from the inner needle along the radial direction of the inner needle.

2. The winding needle according to claim 1, further comprising an elastic member provided in the winding needle, one end of the elastic member being connected to the outer needle, and the other end of the elastic member being connectable to the inner needle or the other outer needle, the elastic member being adapted to apply a force directed in the direction of the inner needle to the outer needle.

3. A winding needle according to claim 1 or 2, wherein the first structural member comprises a first inclined surface inclined relative to the axis of the inner needle and forming a first angle with the axis of the inner needle, the first inclined surface being held against the outer needle so that the outer needle can move along the first inclined surface relative to the first structural member.

4. A needle according to claim 3, wherein the first included angle is in the range of 40 ° to 50 °.

5. The winding needle according to claim 3 or 4, wherein the length of the first inclined surface ranges from 3mm to 5mm.

6. The winding needle according to any one of claims 3 to 5, further comprising a second structural member, the second structural member and the first structural member being disposed at opposite ends of the inner needle in the axial direction of the inner needle, respectively, the second structural member being held against the outer needle at least in the axial direction of the inner needle;

the first structural member is movable relative to the second structural member in an axial direction of the inner needle.

7. The winding needle according to claim 6, wherein the second structural member includes a second bevel, the second bevel bearing against the outer needle, the second bevel forming a second angle with the axis of the inner needle;

The projection of the intersection of the plane of the second inclined plane and the plane of the first inclined plane along the radial direction of the inner needle is positioned in the middle area of the inner needle.

8. The needle of claim 7, wherein the second angle is equal to the first angle.

9. The winding needle according to claim 7 or 8, wherein the outer needle is provided with two third structural members, the two third structural members are arranged at two ends of the outer needle along the axial direction of the inner needle, and the two third structural members are respectively abutted against the first structural member and the second structural member.

10. The winding needle according to claim 9, wherein each of said third structural members includes a third bevel, one of said third bevels being parallel to and abutting said first bevel adjacent thereto, and the other of said third bevels being parallel to and abutting said second bevel adjacent thereto.

11. The winding needle according to any one of claims 1 to 10, wherein the first structural member is fixedly connected to the inner needle;

The winding needle further comprises a driving assembly for driving the inner needle to move along the axial direction of the inner needle so as to push the outer needle to be far away from the inner needle along the radial direction of the inner needle through the first structural part.

12. The winding needle according to any one of claims 1 to 11, wherein the outer needle is provided with an air inlet hole;

at least two outer needles can enclose into the air flow space, the air flow space is communicated with the air inlet hole, and the air flow space is used for being communicated with the air extractor to form negative pressure in the air flow space.

13. The winding needle according to claim 12, wherein the number of the air inlet holes is at least two, and the at least two air inlet holes are uniformly distributed on the outer needle.

14. The winding needle according to claim 13, wherein the aperture range of the air inlet holes is 1 mm-2 mm, and the distance between two adjacent air inlet holes is 2 mm-4 mm.

15. The winding needle according to any one of claims 12 to 14, wherein the negative pressure is in the range of-50 KPa to-75 KPa.

16. The winding needle according to any one of claims 12-15, wherein an air flow channel is formed on the inner needle, wherein the air flow channel is communicated with the air flow space, and one end of the air flow channel is used for being communicated with the air suction device so as to suck air in the air flow space out of the winding needle through the air flow channel.

17. The winding needle according to claim 12, wherein the outer needle comprises a middle portion, and both ends of the middle portion along the axial direction of the inner needle are connected with end portions, and the end portions are abutted against the first structural member;

the air inlet hole is at least arranged on the middle part, and the air flow space is at least formed between the middle parts of the different outer needles.

18. The winding needle according to claim 17, wherein the thickness of the intermediate portion ranges from 5mm to 8mm.

19. A needle as claimed in claim 17 or 18, wherein the end portion is detachably connected to the intermediate portion.

20. The winding needle according to any one of claims 1 to 19, wherein a blanking groove is further provided on a peripheral side surface of the outer needle;

At least one end of the blanking groove is communicated with the space outside the winding needle in the axial direction of the inner needle.

21. A winding device comprising a winding needle according to any one of claims 1-20.