JP7293747B2 - power storage device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an electric storage device having an exterior body that accommodates a power storage element, and that includes an exterior body having a first exterior body and a second exterior body that are joined to each other.

2. Description of the Related Art Conventionally, a power storage device is known that includes an exterior body in which a power storage element is housed, the exterior body having a first exterior body and a second exterior body that are joined to each other. For example, in Patent Document 1, box-shaped first and second battery pack main bodies (exterior bodies) in which batteries (electrical storage elements) are housed are combined with the first battery pack main body (first exterior body). Consists of a projection formed on the edge of the second battery pack main body (second exterior body) and a recess formed on the edge of the first battery pack body (first exterior body) combined with the projection. A battery pack (power storage device) is disclosed.

JP-A-2000-294212

However, in the above-described conventional power storage device, the first exterior body and the second exterior body cannot be effectively joined, and the bondability between the first exterior body and the second exterior body may deteriorate. There is a problem. In other words, in the above-described conventional power storage device, the convex portion of the second exterior body is inserted into the concave portion of the first exterior body. , and found that the bondability between the first exterior body and the second exterior body may deteriorate. For example, if the recess is deep or narrow, it becomes difficult to inject an adhesive into the recess, or chemical cleaning or surface treatment of the bottom surface of the recess, which is the bonding portion, becomes difficult. becomes difficult. In such a case, the first exterior body and the second exterior body cannot be effectively joined, and the bondability between the first exterior body and the second exterior body is lowered.

The present invention has been made in view of the above problems, and provides an electricity storage device capable of improving bonding between a first exterior body and a second exterior body of an exterior body in which an energy storage element is housed. for the purpose.

To achieve the above object, a power storage device according to one aspect of the present invention includes a power storage element and an exterior body that houses the power storage element, wherein the exterior bodies are bonded to each other. It has a first exterior body and a second exterior body, and the first exterior body includes a groove portion into which the second exterior body is inserted, and a protrusion that protrudes from the bottom surface of the groove portion and is joined to the second exterior body. and

According to this, in the power storage device, the exterior body has a first exterior body and a second exterior body that are joined together, and the first exterior body protrudes from the bottom surface of the groove into which the second exterior body is inserted. It has a projecting portion that is joined to the second exterior body. In this way, the projection that protrudes from the bottom surface of the groove is provided on the first exterior body, and the projection is joined to the second exterior body. As a result, it is possible to increase the area of the joint portion of the first exterior body with the second exterior body, so that it is possible to improve the joint strength between the first exterior body and the second exterior body. In addition, it becomes easy to apply an adhesive to the tip portion of the projecting portion, and to chemically clean or surface-treat the tip portion. As a result, the bonding between the first exterior body and the second exterior body can be effectively performed, so that the bondability between the first exterior body and the second exterior body can be improved.

Further, the second exterior body may have a recess into which the projecting portion is inserted and joined to the projecting portion.

According to this, the second armor has a recess into which the protrusion of the first armor is inserted and joined to the protrusion. In this way, since the second exterior body has the concave portion that is joined to the projecting portion of the first exterior body, it is possible to increase the bonding area between the first exterior body and the second exterior body. , it is possible to improve the bonding strength between the first exterior body and the second exterior body. In addition, by inserting the protruding portion of the first exterior body into the recessed portion of the second exterior body, the gap between the first exterior body and the second exterior body can be reduced, thereby improving the sealing performance. can be made As a result, it is possible to improve the bondability between the first exterior body and the second exterior body.

Further, the first exterior body may have a plurality of the projecting portions arranged side by side in the extending direction of the groove portion.

According to this, since the first exterior body has a plurality of protrusions arranged in the extending direction of the groove, the first exterior body and the second exterior body are joined by the plurality of protrusions. As a result, the bonding strength between the first exterior body and the second exterior body can be improved, so that the bondability between the first exterior body and the second exterior body can be further improved.

Further, the projecting portion may have a wide portion wider than the tip portion closer to the bottom surface of the groove than the tip portion.

According to this, the protruding portion of the first exterior body has a wide portion wider than the tip portion closer to the root side (bottom side of the groove portion) than the tip portion. In this way, since the protruding portion of the first exterior body is formed to have a wider width from the tip side toward the root side, it becomes easier to apply the adhesive to the protruding portion, and the protruding portion can be easily removed. Easier to chemically clean and surface treat. As a result, it is possible to improve the bondability between the first exterior body and the second exterior body.

Further, the first exterior body may have a plurality of protrusions arranged side by side in a direction crossing the extending direction of the groove when viewed from the extending direction of the groove.

According to this, since the first exterior body has a plurality of protrusions arranged in a direction intersecting with the extending direction of the groove, the first exterior body and the second exterior body are separated by the plurality of protrusions. spliced. As a result, the bonding strength between the first exterior body and the second exterior body can be improved, so that the bondability between the first exterior body and the second exterior body can be further improved.

Further, the first exterior body may have a plurality of the projections arranged at non-rotationally symmetrical positions when viewed from the direction in which the first exterior body and the second exterior body are arranged.

According to this, the first exterior body has a plurality of protrusions arranged at non-rotationally symmetrical positions. In this way, in the first armor, since the plurality of projections are arranged at positions that are not rotationally symmetrical, when the first armor and the second armor are joined together, it is possible to It is possible to prevent the second exterior body from being arranged in the wrong direction. As a result, it is possible to easily perform the work of joining the first exterior body and the second exterior body, so that it is possible to improve the bondability between the first exterior body and the second exterior body.

The present invention can be realized not only as such a power storage device, but also as an exterior body (first exterior body and second exterior body).

According to the power storage device of the present invention, it is possible to improve the bondability between the first exterior body and the second exterior body of the exterior body in which the energy storage element is housed.

1 is a perspective view showing an appearance of a power storage device according to an embodiment; FIG. FIG. 2 is an exploded perspective view showing each component when the power storage device according to the embodiment is exploded; FIG. 4 is a perspective view showing a configuration of a small lid and a lid body of the exterior lid according to the embodiment; 4 is a cross-sectional view showing the configuration of a small lid and a lid body of the exterior lid according to the embodiment; FIG. FIG. 7 is a cross-sectional view showing the configuration of a lid body of an exterior lid according to Modification 1 of the embodiment; FIG. 11 is a cross-sectional view showing the configuration of a lid body of an exterior lid according to Modification 2 of the embodiment; FIG. 11 is a plan view showing the configuration of a lid body of an exterior lid according to Modification 3 of the embodiment;

Hereinafter, power storage devices according to embodiments (and modifications thereof) of the present invention will be described with reference to the drawings. It should be noted that the embodiments described below are all comprehensive or specific examples. Numerical values, shapes, materials, components, arrangement positions and connection forms of components, manufacturing processes, order of manufacturing processes, and the like shown in the following embodiments are examples, and are not intended to limit the present invention. In addition, among the constituent elements in the following embodiments, constituent elements that are not described in independent claims representing the highest concept will be described as arbitrary constituent elements. Also, in each drawing, dimensions and the like are not strictly illustrated.

In the following description and drawings, the direction in which the energy storage elements are arranged or the direction in which the long side surfaces of the container of the energy storage elements face each other is defined as the X-axis direction. The Y-axis direction is defined as the direction in which a pair of electrode terminals (positive electrode side and negative electrode side) in one storage element are arranged, or the direction in which the short sides of the container of the storage element face each other. The Z-axis direction is the alignment direction of the exterior main body and the lid of the exterior body of the power storage device, the alignment direction of the first exterior body and the second exterior body, the alignment direction of the container body and the lid of the storage element, or the vertical direction. defined as These X-axis direction, Y-axis direction, and Z-axis direction are directions that cross each other (perpendicularly in this embodiment). Although the Z-axis direction may not be the vertical direction depending on the mode of use, the Z-axis direction will be described below for convenience of explanation. Further, in the following description, for example, the positive direction of the X-axis indicates the direction of the arrow of the X-axis, and the negative direction of the X-axis indicates the opposite direction to the positive direction of the X-axis. The same applies to the Y-axis direction and the Z-axis direction.

(Embodiment)
[1 General description of power storage device 10]
First, a general description of power storage device 10 in the present embodiment will be given. FIG. 1 is a perspective view showing the appearance of power storage device 10 according to the present embodiment. FIG. 2 is an exploded perspective view showing each component when power storage device 10 according to the present embodiment is exploded.

Power storage device 10 is a device capable of charging electricity from the outside and discharging electricity to the outside, and has a substantially rectangular parallelepiped shape in the present embodiment. For example, the power storage device 10 is a battery module (assembled battery) used for power storage, power supply, and the like. Specifically, the power storage device 10 is, for example, an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), an automobile such as a gasoline automobile, a motorcycle, a watercraft, a snowmobile, or an agricultural vehicle. Machinery, construction machinery, electric railcars such as electric trains, monorails, linear motor cars, etc., for driving or starting engines, or for stationary batteries used for home use or generators etc.

As shown in FIG. 1, the power storage device 10 includes an exterior body 100. As shown in FIG. etc. are accommodated. Note that the power storage device 10 monitors spacers arranged between the power storage elements 400 , wiring for voltage measurement of the power storage elements 400 , wiring for temperature measurement, thermistors, and the charge state and discharge state of the power storage elements 400 . A circuit board, an electric device such as a relay, etc. may be provided for this purpose.

The exterior body 100 is a box-shaped (substantially rectangular parallelepiped) container (module case) that constitutes the exterior body of the power storage device 10 . That is, the exterior body 100 is arranged outside the plurality of power storage elements 400, the busbar frame 600, the plurality of busbars 700, and the like, and places the power storage elements 400 and the like in predetermined positions to protect them from impacts and the like. In addition, the exterior body 100 is made of, for example, polycarbonate (PC), polypropylene (PP), polyethylene (PE), polystyrene (PS), polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)), polyethylene terephthalate. Talat (PET), polybutylene terephthalate (PBT), polyether ether ketone (PEEK), tetrafluoroethylene/perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyether sulfone (PES), ABS resin , or formed of an insulating member or the like such as a composite material thereof. The exterior body 100 thereby prevents the power storage element 400 and the like from coming into contact with an external metal member or the like. Note that the exterior body 100 may be formed of a conductive member such as metal as long as the insulation of the power storage element 400 and the like is maintained.

Here, the exterior body 100 has an exterior body main body 200 that constitutes the main body of the exterior body 100 and an exterior body lid 300 that constitutes the lid of the exterior body 100 . The exterior body main body 200 is a bottomed rectangular cylindrical housing (casing) having an opening, and accommodates the power storage element 400 and the like. The exterior cover 300 is a flat rectangular member that is joined to the exterior body 200 by heat sealing or the like to close the opening of the exterior body 200 . A positive electrode external terminal 330 and a negative electrode external terminal 340 are provided on the outer cover body 300 . Power storage device 10 charges electricity from the outside and discharges electricity to the outside through positive electrode external terminal 330 and negative electrode external terminal 340 .

In addition, the outer cover body 300 has a small lid 310 on the upper surface (the surface on the Z-axis positive direction side) on the positive electrode external terminal 330 side, and has a small lid 310a on the negative electrode external terminal 340 side. ing. The small lid 310 is a plate-shaped member having a rectangular shape when viewed from above (as seen from the positive direction of the Z axis), and the small lid 310a has a shape in which a portion of the rectangular shape protrudes into a rectangular shape when viewed from above. It is a plate member having. That is, the small lid 310 has a rotationally symmetrical shape, and the small lid 310a has a non-rotationally symmetrical shape. A portion of the exterior lid 300 to which the small lids 310 and 310a are attached (a portion of the exterior lid 300 other than the small lids 310 and 310a) is referred to as a lid body 320 . That is, the lid main body 320 has openings at positions on the positive electrode external terminal 330 side and at positions on the negative electrode external terminal 340 side, and the lid main body 320 and the small lids 310 and 310a are joined at the positions of the openings. As a result, the openings are closed by the small lids 310 and 310a.

The opening of the lid main body 320 connects, for example, a bus bar (not shown) connected to the bus bar 700 and a bus bar (not shown) connected to the positive external terminal 330 or the negative external terminal 340. It is used as an opening for work to expose the connection part and perform bolt fastening. The opening of the lid body 320 can also be used as a connector for connecting control wiring or the like, or an opening for accessing a housing space housing a valve or the like for discharging the exhaust gas from the electric storage element 400. can.

Here, the lid main body 320 is an example of a first exterior body, and the small lids 310 and 310a are an example of a second exterior body. The lid body main body 320 and the exterior body main body 200 can also be used as an example of the first exterior body. The exterior body main body 200, the small lids 310 and 310a of the exterior body lid body 300, and the lid body body 320 may all be made of the same material, or any of them may be made of a different material. may be A detailed description of the configurations of the small lids 310 and 310a of the exterior lid body 300 and the lid body body 320 will be given later.

The storage element 400 is a secondary battery (single battery) capable of charging and discharging electricity, more specifically, a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. . The power storage element 400 has a flat rectangular parallelepiped (rectangular) shape, and in the present embodiment, 16 power storage elements 400 are arranged side by side in the X-axis direction. In addition, the shape of the electric storage element 400, the arrangement direction of the electric storage element 400, the number, etc. are not limited. Moreover, the storage element 400 is not limited to a non-aqueous electrolyte secondary battery, and may be a secondary battery other than a non-aqueous electrolyte secondary battery, or may be a capacitor. Also, the power storage device 400 may be a primary battery that allows the stored electricity to be used without being charged by the user, instead of a secondary battery. Furthermore, power storage element 400 may be a battery using a solid electrolyte. Also, the storage element 400 can be a laminated storage element.

Specifically, the power storage element 400 includes a container 410 and a pair of electrode terminals 420 (positive electrode side and negative electrode side). Further, an electrode body, a pair of current collectors, an electrolytic solution (non-aqueous electrolyte), and the like are accommodated inside the container 410, but illustration of these is omitted. The container 410 is a rectangular parallelepiped (square) container, and is made of, for example, a metal such as stainless steel, aluminum, an aluminum alloy, iron, or a plated steel plate. The electrode terminal 420 is a terminal (positive electrode terminal and negative electrode terminal) that is electrically connected to the positive electrode plate and the negative electrode plate of the electrode assembly via the current collector, and is made of, for example, aluminum or an aluminum alloy. .

The electrode assembly is a power storage element (power generation element) formed by laminating a positive electrode plate, a negative electrode plate, and a separator. The positive electrode plate is formed by forming a positive electrode active material layer on a positive electrode base material layer, which is a long belt-shaped collector foil made of metal such as aluminum or an aluminum alloy. The negative electrode plate is formed by forming a negative electrode active material layer on a negative electrode base material layer, which is a long band-shaped collector foil made of a metal such as copper or a copper alloy. As the active material used for the positive electrode active material layer and the negative electrode active material layer, any known material can be appropriately used as long as it can intercalate and deintercalate lithium ions. The current collectors are members (positive electrode current collector and negative electrode current collector) having conductivity and rigidity electrically connected to the electrode terminal 420 and the electrode body. The positive electrode current collector is made of aluminum, an aluminum alloy, or the like, like the positive electrode substrate layer of the positive electrode plate, and the negative electrode current collector is made of copper, a copper alloy, or the like, like the negative electrode substrate layer of the negative electrode plate. It is As the electrolytic solution, there is no particular limitation on the type as long as it does not impair the performance of the storage element 400, and various types can be selected.

The busbar frame 600 is a rectangular plate-like member that insulates the busbar 700 from other members and regulates the position of the busbar 700 . Specifically, the busbar 700 is placed on the busbar frame 600 and positioned, and the busbar frame 600 is placed on the plurality of power storage elements 400 and positioned with respect to the plurality of power storage elements 400 . As a result, bus bar 700 is positioned with respect to multiple power storage elements 400 . The busbar frame 600 is made of an insulating material such as PC, PP, PE, PS, PPS, PPE (including modified PPE), PET, PBT, or ABS resin. It may be made of any material.

The bus bar 700 is a rectangular plate-shaped member arranged above the plurality of storage elements 400 and electrically connecting the electrode terminals of the plurality of storage elements 400 . Bus bar 700 is also connected to positive external terminal 330 and negative external terminal 340 via another bus bar (not shown). Bus bar 700 is formed of a conductive member made of metal such as aluminum, aluminum alloy, copper, copper alloy, or the like. In the present embodiment, bus bar 700 connects four power storage elements 400 in parallel to form four power storage element groups, and connects the four power storage element groups in series. In addition, bus bar 700 connects positive external terminal 330 to the positive terminals of four energy storage elements 400 in the energy storage element group arranged on the positive external terminal 330 side (X-axis plus direction side). The same applies to the negative electrode side. Bus bar 700 may connect all 16 power storage elements 400 in series, or may have another configuration.

[2 Description of Configurations of Small Lids 310 and 310a of Exterior Lid 300 and Lid Body 320]
Next, the configurations of the small lids 310 and 310a of the exterior lid body 300 and the lid body body 320 will be described in detail. Specifically, the configuration of the joints between the small lids 310 and 310a and the lid body 320 will be described in detail below. Although the shape of the small lid 310 and the small lid 310a are different when viewed from above, the structure of the joint portion with the lid main body 320 is the same. Description of is omitted.

FIG. 3 is a perspective view showing the configuration of the small lid 310 and the lid body 320 of the exterior lid 300 according to the present embodiment. Specifically, FIG. 3 is a perspective view showing the configuration when the small lid 310 is removed from the lid body 320 (or before the small lid 310 and the lid body 320 are joined). FIG. 4 is a cross-sectional view showing the configuration of the small lid 310 and the lid body 320 of the exterior lid 300 according to the present embodiment. Specifically, FIG. 4(a) is a cross-sectional view showing the configuration when the small lid 310 and the lid main body 320 shown in FIG. 3 are cut along line IVa-IVa, and FIG. 4(b). [Fig. 4] is a sectional view showing a configuration when the small lid 310 and the lid main body 320 shown in Fig. 3 are cut along line IVb-IVb. 4(c) and 4(d) are sectional views showing the structure when the small lid 310 and the lid body 320 of FIGS. 4(a) and 4(b) are joined together.

As shown in FIGS. 3 and 4, the small lid 310 has a small lid projecting portion 311 projecting in the negative Z-axis direction from the outer edge portion of a rectangular shape when viewed in the Z-axis direction. Specifically, the small lid 310 protrudes in the negative Z-axis direction from the entire circumference of the outer edge portion and is recessed in the positive Z-axis direction on a rectangular annular side wall extending along the outer edge portion. A small lid projecting portion 311 is formed by forming the concave portion 312 . In this embodiment, a plurality of small lid protruding portions 311 and a plurality of small lid recessed portions 312 are alternately arranged along the entire circumference of the side wall.

Here, the small lid concave portion 312 is a concave portion into which a body projection portion 324 of the lid body body 320 described later is inserted and joined to the body projection portion 324. It has a shape recessed in a semicircular shape in the positive direction. Therefore, the small lid projecting portion 311 has a shape projecting so that the width becomes narrower in the negative Z-axis direction.

The lid main body 320 has an outer wall portion 321 , an inner wall portion 322 , and a groove portion 323 formed between the outer wall portion 321 and the inner wall portion 322 . The outer wall portion 321 is a wall portion that surrounds the outer periphery of the groove portion 323 and is formed in a rectangular and annular shape when viewed from the Z-axis direction. The outer wall portion 321 is formed so that the surface on the Z-axis positive direction side is at the same height as the surface of the lid body 320 on the Z-axis positive direction side. The inner wall portion 322 is a wall portion that surrounds the inner periphery of the groove portion 323 that is arranged inside the outer wall portion 321 and formed in a rectangular and annular shape when viewed from the Z-axis direction. The inner wall portion 322 is formed to have a lower height in the Z-axis direction than the outer wall portion 321 . The heights of the outer wall portion 321 and the inner wall portion 322 are not particularly limited, and may be different from the heights described above. For this reason, the above height is preferable.

The groove portion 323 is a groove surrounded by the outer wall portion 321 and the inner wall portion 322 and having a rectangular shape and an annular shape when viewed from the Z-axis direction. That is, the groove portion 323 is a groove surrounded by the outer wall portion 321, the inner wall portion 322, and the groove bottom surface 323a (see FIG. 4) which is the bottom surface arranged on the Z-axis negative direction side. In the present embodiment, the groove bottom surface 323a is a flat surface (flat surface) parallel to the XY plane. With such a configuration, the small lid 310 is inserted into the groove portion 323 . Specifically, the small lid projecting portion 311 and the small lid recessed portion 312 of the small lid 310 are inserted into the groove portion 323 . In the present embodiment, the small lid protruding portion 311 is inserted until its tip abuts against the groove bottom surface 323a via an adhesive, and is joined to the groove bottom surface 323a.

Further, the lid main body 320 has a main body protruding portion 324 that protrudes from the groove bottom surface 323 a of the groove portion 323 and is joined to the small lid 310 . Specifically, the lid main body 320 has a plurality of main body protruding portions 324 arranged side by side in the extending direction of the groove portion 323 (the Y-axis direction in FIG. 4). In other words, a plurality of main body projecting portions 324 are arranged side by side over the entire circumference of the groove portion 323 . In the present embodiment, the plurality of lid bodies 320 are arranged side by side at regular intervals while being integrated with the outer wall portion 321 and the inner wall portion 322 of the groove portion 323 .

Here, the body protruding portion 324 has a front end portion 324a arranged on the Z-axis positive direction side, and a wide portion 324b arranged on the groove bottom surface 323a side (Z-axis negative direction side) of the groove portion 323 from the front end portion 324a. , (see FIG. 4). The wide portion 324b is formed to be wider than the tip portion 324a in the extending direction of the groove portion 323 (the Y-axis direction in FIG. 4). In other words, the body projecting portion 324 is a projecting portion projecting so that the width becomes narrower toward the Z-axis plus direction. Specifically, the body projecting portion 324 has a semicircular projecting shape corresponding to the small lid concave portion 312 of the small lid 310 . With such a configuration, the main body protrusion 324 is inserted into the small lid recess 312 and joined to the small lid recess 312 . In other words, the small lid protrusion 311 is inserted between two adjacent main body protrusions 324 and joined to the two main body protrusions 324 .

The connection between the small lid 310 and the lid main body 320 is performed as follows. First, the inside of the groove 323 of the lid body 320 is surface-treated so that it can be easily joined to the small lid 310 . For example, the inner surface of the groove 323 is exposed to media such as oxygen radicals for plasma treatment or corona treatment, or sandblasted by spraying a fine abrasive to increase the wettability of the inner surface of the groove 323. , fine unevenness is formed on the inner surface of the groove 323 . Here, the effect of the surface treatment in the groove portion 323 of the lid body 320 is higher in the portion closer to the Z-axis plus direction side. Therefore, in the body projecting portion 324, the tip portion 324a is formed to have higher wettability than the wide portion 324b, and the wide portion 324b is formed to have higher wettability than the groove bottom surface 323a. Alternatively, the tip portion 324a is formed with an uneven portion that is rougher than the wide portion 324b, and the wide portion 324b is formed with an uneven portion that is rougher than the groove bottom surface 323a.

Next, the surface of the plurality of small lid projections 311 and the plurality of small lid recesses 312 of the small lid 310, or the inner surface of the groove 323 of the lid body 320 (the plurality of body projections 324, the groove bottom surface 323a, the outer wall 321 and the surface of the inner wall portion 322) is coated with an adhesive. Then, as shown in FIG. 4, the plurality of small lid projecting portions 311 and the plurality of small lid recessed portions 312 of the small lid 310 are inserted into the groove portion 323 of the lid body 320, and the plurality of body projecting portions 324 and the groove bottom surface are inserted into the groove portion 323 of the lid body 320. 323a, the outer wall portion 321 and the inner wall portion 322 are bonded together. Thus, the exterior body 100 (the exterior body lid 300) has the lid body body 320 (first exterior body) and the small lid 310 (second exterior body) that are joined together.

[3 Explanation of effects]
As described above, according to power storage device 10 according to the embodiment of the present invention, exterior body 100 includes lid body main body 320 (first exterior body) and small lid 310 (second exterior body) that are joined to each other. have. The lid main body 320 has a main body projecting portion 324 that protrudes from a groove bottom surface 323 a of a groove portion 323 into which the small lid 310 is inserted and is joined to the small lid 310 . In this way, the lid main body 320 is provided with the main body projecting portion 324 projecting from the groove bottom surface 323 a of the groove portion 323 , and the main body projecting portion 324 is joined to the small lid 310 . As a result, the area of the joining portion of the lid body 320 and the small lid 310 can be increased. In addition, it becomes easy to apply an adhesive to the front end portion 324a of the main body projecting portion 324, and to chemically clean or surface-treat the front end portion 324a. For example, when the front end portion 324a of the main body projecting portion 324 is subjected to surface treatment, the front end portion 324a can be easily applied with a medium (oxygen radicals, abrasive for sandblasting, etc.) that contributes to the surface treatment. In addition, since the processing instrument may be arranged so that the medium contacts the tip portion 324 a , the processing instrument can be arranged at a position that is not too close to the lid main body 320 . Therefore, the lid main body 320 can be prevented from coming into contact with the processing instrument or being thermally affected by the processing instrument, and the front end portion 324a of the main body projecting portion 324 can be easily surface-treated. As a result, the lid body main body 320 and the small lid 310 can be effectively joined together, so that the bondability between the lid body body 320 and the small lid 310 can be improved.

It should be noted that improving the bondability means performing the bonding effectively and improving the efficiency of the bonding. For example, improving bonding means improving the bonding strength, improving the sealing (airtightness) of the bonded part, and facilitating the bonding work (facilitating the application of adhesive). facilitating chemical cleaning and surface treatment, preventing misplacement, etc.).

In addition, the small lid 310 has a small lid concave portion 312 into which the body projecting portion 324 of the lid body 320 is inserted and joined to the body projecting portion 324 . Since the small lid 310 has the small lid concave portion 312 that is joined to the main body projecting portion 324 of the lid main body 320 in this way, the joint area between the lid main body 320 and the small lid 310 can be increased. Therefore, the bonding strength between the lid body main body 320 and the small lid 310 can be improved. In addition, by inserting the main body projecting portion 324 of the lid main body 320 into the small lid concave portion 312 of the small lid 310, the gap between the lid main body 320 and the small lid 310 can be reduced. can improve sexuality. As a result, the bondability between the lid body main body 320 and the small lid 310 can be improved.

In addition, since the lid main body 320 has a plurality of main body projecting portions 324 arranged in the extending direction of the groove portion 323, the lid main body 320 and the small lid 310 are joined by the plurality of main body projecting portions 324. . As a result, the joint strength between the lid body main body 320 and the small lid 310 can be improved, so that the bondability between the lid body body 320 and the small lid 310 can be further improved.

Further, the body protruding portion 324 of the lid body 320 has a wide portion 324b wider than the tip portion 324a on the root side (on the side of the groove bottom surface 323a of the groove portion 323) than the tip portion 324a. As described above, the main body projecting portion 324 of the lid body 320 is formed to have a wider width from the tip portion 324a side toward the base side, so that the adhesive can be easily applied to the main body projecting portion 324. Also, chemical cleaning or surface treatment of the main body protrusion 324 is facilitated. Further, when the surface treatment is performed from the Z-axis positive direction side to the Z-axis negative direction side, the surface-treated area increases. As a result, the bondability between the lid body main body 320 and the small lid 310 can be improved.

[4 Description of modified example]
(Modification 1)
Next, Modification 1 of the above embodiment will be described. FIG. 5 is a cross-sectional view showing the configuration of lid bodies 320A to 320C of the exterior lid according to Modification 1 of the present embodiment. Specifically, FIGS. 5A to 5C are diagrams corresponding to the lid main body 320 in FIG. 4B.

First, as shown in (a) of FIG. 5, in a lid body main body 320A in this modified example, unlike the lid body body 320 in the above-described embodiment, a plurality of body projecting portions 324 are spaced apart along a groove portion 323. They are arranged side by side with no space between them. In this manner, the main body protrusion 324 may be arranged at any position. The small lid protrusion 311 and the small lid recess 312 of the small lid 310 have shapes corresponding to the intervals between the main body protrusions 324 . Since other configurations are the same as those of the above-described embodiment, detailed description thereof will be omitted.

Further, as shown in (b) of FIG. 5, in a lid body main body 320B in this modified example, unlike the lid body body 320 in the above-described embodiment, a body protruding portion 325 protruding in a triangular shape is arranged. Further, as shown in (c) of FIG. 5, a lid main body 320C in this modification has a distal end portion 326a in which the upper surface of the distal end portion 324a of the lid main body 320 in the above-described embodiment is flattened. A body protrusion 326 is arranged. Thus, the main body protrusion may have any shape. The small lid protrusion 311 and the small lid recess 312 of the small lid 310 have shapes corresponding to the intervals between the main body protrusions. Since other configurations are the same as those of the above-described embodiment, detailed description thereof will be omitted.

As described above, according to the power storage device according to this modification, the same effects as those of the above-described embodiment can be obtained. In particular, as in this modified example, the body projecting portion provided on the lid body (and the small lid projecting portion and the small lid recessed portion of the small lid) can take various shapes and arrangements.

(Modification 2)
Next, Modification 2 of the above embodiment will be described. FIG. 6 is a cross-sectional view showing the configuration of lid bodies 320D to 320F of the exterior lid according to Modification 2 of the present embodiment. Specifically, FIGS. 6A to 6C are diagrams corresponding to the lid main body 320 in FIG. 4A.

First, as shown in (a) of FIG. 6, a lid main body 320D in this modified example has a main body projecting portion 327 that is spaced apart from the outer wall portion 321 and the inner wall portion 322 . In addition, as shown in FIG. 6(b), the lid main body 320E in this modified example has a main protruding portion 327 that is integrated with the outer wall portion 321 and arranged with a gap from the inner wall portion 322. are doing. In this way, the main body projecting portion may be arranged in any position and shape (thickness) in the width direction (the X-axis direction in FIG. 6) of the groove portion 323 as well. The small lid protrusion 311 and the small lid recess 312 of the small lid 310 have positions and shapes corresponding to the positions and shapes of the main body protrusions. Since other configurations are the same as those of the above-described embodiment, detailed description thereof will be omitted.

Furthermore, as shown in (c) of FIG. 6 , the lid main body 320F in this modified example has a plurality of (two in this modified example) main body projections arranged at intervals from the outer wall portion 321 and the inner wall portion 322. It has a portion 328 . That is, when viewed from the extending direction of the groove portion 323 (the Y-axis direction in FIG. 6), the plurality of main body projecting portions 328 extend in a direction intersecting the extending direction of the groove portion 323 (the width direction of the groove portion 323, the X-axis direction in FIG. 6). direction).

In addition, the plurality of body projecting portions 328 may be arranged at the same position in the extending direction of the groove portion 323, or may be arranged at different positions. Further, the body projecting portion 328 may be integrated with the outer wall portion 321 and the inner wall portion 322 . In this manner, a plurality of main body projecting portions may be arranged in the width direction of the groove portion 323 . The small lid protrusions 311 and the small lid recesses 312 of the small lid 310 have shapes corresponding to the number of main body protrusions. Since other configurations are the same as those of the above-described embodiment, detailed description thereof will be omitted.

As described above, according to the power storage device according to this modification, the same effects as those of the above-described embodiment can be obtained. In particular, since the lid main body 320F in this modified example has a plurality of main body projecting portions 328 arranged in a direction intersecting the extending direction of the groove portion 323, the lid main body 320F and the small lid 310 are arranged in the plurality of protruding portions. It is joined by a body protrusion 328 . As a result, for example, by arranging a plurality of body projecting portions 328 at different positions in the extending direction of the groove portion 323, sealing performance (airtightness) between the lid body body 320F and the small lid 310 can be improved. ) can be improved, and the bonding strength can be improved. Therefore, it is possible to further improve the bondability between the lid main body 320 and the small lid 310 .

(Modification 3)
Next, Modification 3 of the above embodiment will be described. FIG. 7 is a plan view showing the configuration of a lid body 320G of an exterior lid according to Modification 3 of the present embodiment. Specifically, FIG. 7 corresponds to a view when the lid body 320 in FIG. 3 is viewed from the Z-axis plus direction.

As shown in FIG. 7, the lid main body 320G in this modification includes a plurality of main bodies arranged at non-rotationally symmetrical positions when viewed from the direction in which the lid main body 320G and the small lid 310 are arranged (the Z-axis direction). It has a protrusion 324 . In other words, the plurality of main body projecting portions 324 are arranged so as not to be in the same arrangement position when rotated around the center position (center of gravity position) of the area surrounded by the groove portion 323 . The small lid protrusion 311 and the small lid recess 312 of the small lid 310 have shapes corresponding to the positions of the main body protrusion. Since other configurations are the same as those of the above-described embodiment, detailed description thereof will be omitted.

As described above, according to the power storage device according to this modification, the same effects as those of the above-described embodiment can be obtained. In particular, the lid main body 320G in this modified example has a plurality of main body protruding portions 324 arranged at non-rotationally symmetrical positions. In this way, in the lid body 320G, the plurality of body projecting portions 324 are arranged at non-rotationally symmetrical positions. On the other hand, it is possible to suppress arranging the small lid 310 in the wrong direction. As a result, the joining work between the lid body main body 320G and the small lid 310 can be easily performed, so that the bondability between the lid body body 320G and the small lid 310 can be improved.

In the above-described embodiment, the small lid 310a has a non-rotationally symmetrical shape as described above. Therefore, in the small lid 310a, it is possible to prevent the main body projecting portion 324 from being arranged in a non-rotationally symmetrical position, thereby preventing it from being arranged in the wrong direction.

(Other modifications)
Although the power storage device according to the present embodiment and its modification has been described above, the present invention is not limited to the above-described embodiment and its modification. In other words, the embodiments disclosed this time and their modifications are illustrative in all respects and are not restrictive, and the scope of the present invention is indicated by the scope of the claims, and equivalents to the scope of the claims. All changes in meaning and scope are included.

For example, in the above-described embodiment and its modification, the lid body has a plurality of body projecting portions arranged side by side in the extending direction of the groove portion 323 . However, the lid body may have only one body protrusion, and the small lid 310 may have only one small lid recess 312 corresponding to the one body protrusion. .

In the above-described embodiment and its modification, the small lid 310 has the small lid projecting portion 311 and the small lid recessed portion 312 formed on the side wall. However, the small lid 310 has a rectangular side wall in which the small lid protrusion 311 and the small lid recess 312 are not formed, and the side wall is inserted into the groove 323 of the lid body and joined to the main body protrusion. You may decide to do so.

In addition, in the above-described embodiment and its modification, the surface treatment is applied to the main body protrusion of the lid main body, but the main body protrusion may not be subjected to the surface treatment.

Further, in the above-described embodiment and its modification, the body protruding portion of the lid body body is formed to have a wider width from the tip side toward the root side. However, the body protruding portion of the lid body may be formed with the same width on the tip side and the root side, or may be wider on the tip side than on the root side.

Further, in the above embodiment and its modified example, the lid main body and the small lid 310 are joined by being adhered with an adhesive. However, the lid main body and the small lid 310 may be joined by adhesion other than adhesive such as double-sided tape, or may be joined by a method other than adhesion such as welding (thermal welding). can be In this way, since the lid main body has a projecting portion that is joined to the small lid 310, the joint area can be increased, so the joint strength between the lid main body and the small lid 310 is improved. can be achieved, and the bondability between the lid main body 320 and the small lid 310 can be improved.

Further, in the above-described embodiment and its modification, the lid body of the exterior lid body is an example of the first exterior body, and the small lid is an example of the second exterior body. However, the small lid may be an example of the first exterior body, and the lid main body may be an example of the second exterior body. That is, the small lid may have a groove and a projecting portion projecting from the bottom surface of the groove, and the lid body may be inserted into the groove and joined to the projecting portion. Alternatively, the exterior body main body may be an example of the first exterior body, and the exterior lid body may be an example of the second exterior body. The body main body may be an example of the second exterior body. That is, when the exterior body is composed of two or more members, any two of the two or more members can be used as the first exterior body and the second exterior body. However, if the bonding area between the first exterior body and the second exterior body is large, it takes time for the adhesive to harden, etc., so the two members with the small bonding area are used as the first exterior body and the second exterior body. is preferred.

In addition, in the above-described embodiment and its modification, the plurality of power storage elements 400 are inserted into the exterior body 100 without being restrained. It may be inserted into the exterior body 100 .

Moreover, the form constructed by arbitrarily combining the constituent elements included in the above embodiment and its modifications is also included in the scope of the present invention.

Moreover, the present invention can be realized not only as such a power storage device, but also as an exterior body (first exterior body and second exterior body).

INDUSTRIAL APPLICABILITY The present invention can be applied to a power storage device having a power storage element such as a lithium ion secondary battery.

10 Power storage device 100 Exterior body 200 Exterior body main body 300 Exterior body lid body 310, 310a Small lid 311 Small lid protrusion 312 Small lid recess 320, 320A, 320B, 320C, 320D, 320E, 320F, 320G Lid body 321 Outer wall 322 inner wall portion 323 groove portion 323a groove bottom surface 324, 325, 326, 327, 328 main body protrusion portion 324a, 326a tip portion 324b wide portion 400 power storage element

Claims (9)

A power storage device comprising a power storage element and an exterior body housing the power storage element,
The exterior body has a first exterior body and a second exterior body that are joined to each other,
The first exterior body is
a groove into which the second exterior body is inserted;
a protrusion that protrudes from the bottom surface of the groove and is joined to the second exterior body ,
The protruding portion and the second exterior body are bonded to each other by adhesion or welding at their opposing surfaces.
storage device. A power storage device comprising a power storage element and an exterior body housing the power storage element,
The exterior body has a first exterior body and a second exterior body that are joined to each other,
The first exterior body is
a groove into which the second exterior body is inserted;
a protrusion that protrudes from the bottom surface of the groove and is joined to the second exterior body ,
The first exterior body is
Having a plurality of protrusions arranged side by side in a direction crossing the extending direction of the groove when viewed from the extending direction of the groove
storage device. The power storage device according to claim 1 or 2 , wherein the second exterior body has a recess into which the protrusion is inserted and joined to the protrusion. Of the walls on both sides of the groove, the wall located inside the first exterior body is lower in height in the projection direction of the projection than the wall located outside the first exterior body.
The electricity storage device according to any one of claims 1 to 3. When viewed from the direction in which the walls on both sides of the groove are arranged, the edge of at least one of the walls on both sides of the groove in the direction in which the protrusion overlaps the protrusion.
The electricity storage device according to any one of claims 1 to 4. In the projecting part, the tip part in the projecting direction of the projecting part has higher wettability than the root part, or rough irregularities are formed.
The electricity storage device according to any one of claims 1 to 5. The protrusion is spaced apart from at least one of the walls on both sides of the groove.
The power storage device according to any one of claims 1 to 6. The power storage device according to any one of claims 1 to 7 , wherein the first exterior body has a plurality of the projecting portions arranged side by side in the extending direction of the groove portion. The first exterior body is
The power storage device according to any one of claims 1 to 8 , wherein the power storage device has a plurality of protrusions arranged at rotationally asymmetric positions when viewed from the direction in which the first exterior body and the second exterior body are arranged. .

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