Electric storage device

Abstract

To provide a power storage device which can protect power storage cells from a load inputted to a case in the vertical direction.SOLUTION: A power storage device comprises: a plurality of power storage stacks 100; a case; and a protection structure 300 which protects a plurality of power storage cells 110 from a load inputted to the case in the vertical direction. The case has a bottom wall 212, a top wall, and a peripheral wall. The protection structure 300 has: a cross member 310; and a load transmission member 320 disposed on the cross member 310. The load transmission member 320 has at least one contact part 327 which can be compressed and deformed in the perpendicular direction, and which also comes into contact with a pair of the power storage stacks 100 adjacent to each other in the perpendicular direction when they are compressed.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a power storage device.

Background Art

[0002] For example, Japanese Patent Application Laid-Open No. 2014-24488 discloses a battery unit including a battery case having a battery tray and a battery cover, a plurality of batteries disposed in the battery case, and a battery bracket that is a single plate and fixed to the battery tray. The battery tray has a bottom wall, a plurality of ribs erected on the bottom wall, and a plurality of partition walls erected on the bottom wall.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the battery unit described in Japanese Patent Application Laid-Open No. 2014-24488, when a vertical load is applied to the case, there is a concern that the load is transmitted to the power storage cells.

[0005] An object of the present disclosure is to provide a power storage device capable of protecting power storage cells from a load applied in the vertical direction to the case.

Means for Solving the Problems

[0006] A power storage device according to an aspect of the present disclosure includes a plurality of power storage cells arranged so as to be aligned in one direction, and a plurality of power storage stacks arranged so as to be aligned in an orthogonal direction orthogonal to both the one direction and the vertical direction, a case that houses the plurality of power storage stacks, and a protection structure provided in the case for protecting the plurality of power storage cells from a load input in the vertical direction with respect to the case. The case has a bottom wall disposed below the plurality of power storage stacks, a top wall disposed above the plurality of power storage stacks, and a peripheral wall that connects a peripheral edge of the bottom wall and a peripheral edge of the top wall and surrounds the plurality of power storage stacks. The protection structure includes a cross member disposed between a pair of the power storage stacks adjacent to each other in the orthogonal direction on the bottom wall, having a shape extending in the one direction and connected to the peripheral wall, and a load transmission member disposed on the cross member. The load transmission member is compressibly deformable in the orthogonal direction and has at least one contact portion that contacts a pair of the power storage stacks adjacent to each other in the orthogonal direction in a compressed state.

Advantages of the Invention

[0007] According to the present disclosure, it is possible to provide a power storage device capable of protecting power storage cells from a load input in the vertical direction with respect to a case.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0009] Embodiments of the present disclosure will be described with reference to the drawings. In the drawings referred to below, the same or corresponding members are denoted by the same reference numerals.

[0010] FIG. 1 is a perspective view schematically showing the configuration of an energy storage device according to an embodiment of the present disclosure. This energy storage device 1 is mounted on a vehicle, for example.

[0011] As shown in FIGS. 1 to 3, the energy storage device 1 includes a plurality of energy storage stacks 100, a case 200, and a protection structure 300.

[0012] As shown in FIG. 1, each energy storage stack 100 has a plurality of energy storage cells 110 arranged side by side in one direction. Examples of the energy storage cell 110 include a lithium-ion battery. Each energy storage cell 110 is formed in a rectangular parallelepiped shape. As shown in FIG. 1, the plurality of energy storage stacks 100 are arranged side by side in a direction orthogonal to both the one direction and the vertical direction.

[0013] Each energy storage stack 100 has a first unit stack 101, a second unit stack 102, and an intermediate plate 103.

[0014] The first unit stack 101 is arranged on one side in the one direction. The first unit stack 101 includes some of the plurality of energy storage cells 110. The first unit stack 101 may include an end plate. The end plate is arranged outside the outermost energy storage cell 110 in the one direction.

[0015] The second unit stack 102 is disposed on the other side in one direction. The second unit stack 102 includes power storage cells 110 other than those included in the first unit stack 101 among the plurality of power storage cells 110. In the present embodiment, the number of power storage cells 110 included in the second unit stack 102 is the same as the number of power storage cells 110 included in the first unit stack 101. The second unit stack 102 may include an end plate disposed outside the power storage cells 110 in one direction.

[0016] The intermediate plate 103 is disposed between the first unit stack 101 and the second unit stack 102. The intermediate plate 103 is disposed at the center of the power storage stack 100 in one direction. The intermediate plate 103 is made of a synthetic resin or the like.

[0017] The case 200 houses a plurality of power storage stacks 100. The case 200 has a lower case 210 and an upper case 220 (see FIG. 3). Note that in FIGS. 1 and 2, the illustration of the upper case 220 is omitted.

[0018] The lower case 210 has a shape that opens upward. The lower case 210 is made of metal, synthetic resin, or the like. The lower case 210 has a bottom wall 212, a lower surrounding wall 214, and a lower flange 216.

[0019] The bottom wall 212 is disposed below the plurality of power storage stacks 100. As shown in FIGS. 2 and 3, a raised portion 212a that bulges upward is formed at the central portion of the bottom wall 212 in one direction. The top of the raised portion 212a is formed flat. As shown in FIG. 3, the intermediate plate 103 is placed on the raised portion 212a.

[0020] The lower surrounding wall 214 stands up from the peripheral edge of the bottom wall 212 and surrounds the lower periphery of the plurality of power storage stacks 100.

[0021] The lower flange 216 has a shape that projects outward from the upper end of the lower surrounding wall 214.

[0022] The upper case 220 has a shape that opens downward. The upper case 220 houses a plurality of power storage stacks 100 together with the lower case 210. The upper case 220 is made of metal, synthetic resin, or the like. The upper case 220 has a top wall 222, an upper surrounding wall 224, and an upper flange 226.

[0023] The top wall 222 is disposed above the plurality of power storage stacks 100. The top wall 222 may be formed in a flat plate shape. A gap is formed between the top wall 222 and each power storage stack 100.

[0024] The upper surrounding wall 224 extends downward from the peripheral edge of the top wall 222 and surrounds the periphery of the upper portions of the plurality of power storage stacks 100. The upper surrounding wall 224 and the lower surrounding wall 214 together form a peripheral wall. The peripheral walls 214, 224 connect the peripheral edge of the bottom wall 212 and the peripheral edge of the top wall 222 and surround the periphery of the plurality of power storage stacks 100.

[0025] The upper flange 226 has a shape that projects outward from the lower end of the upper surrounding wall 224. The upper flange 226 is fixed to the lower flange 216 by bolts or the like.

[0026] The protective structure 300 is provided inside the case 200 and protects the plurality of power storage cells 110 from the load input in the vertical direction with respect to the case 200. As shown in FIG. 3, the length of the protective structure 300 in the vertical direction is larger than the length of the plurality of power storage cells 110 in the vertical direction. As shown in FIG. 4, the protective structure 300 is disposed between a pair of intermediate plates 103 adjacent to each other in the orthogonal direction. In the present embodiment, the protective structure 300 has a cross member 310 and a load transmission member 320. In FIG. 3, the first unit stack 101, the second unit stack 102, and the intermediate plate 103 are shown by a two-dot chain line, and in FIG. 4, the illustration of the first unit stack 101 and the second unit stack 102 is omitted. Also, actually, after the power storage stack 100 is assembled to the lower case 210, the load transmission member 320 is placed on the cross member 310, but in FIG. 2, for the sake of explanation, the state before each power storage stack 100 is accommodated in the lower case 210 is shown.

[0027] The cross member 310 is disposed on the bottom wall 212. The cross member 310 has a shape extending in one direction and is connected to the lower surrounding wall 214. That is, the cross member 310 has a function of reinforcing the lower surrounding wall 214. The cross section of the cross member 310 in a plane orthogonal to the one direction is formed in a shape convex upward. The upper surface of the cross member 310 is preferably formed flat. The cross member 310 is disposed between a pair of power storage stacks 100 adjacent to each other in the orthogonal direction. That is, the cross member 310 partitions between a pair of power storage stacks 100 adjacent to each other in the orthogonal direction.

[0028] The load transmission member 320 is disposed on the cross member 310. The load transmission member 320 transmits the load input downward with respect to the top wall 222 to the cross member 310. The load transmission member 320 transmits the load input upward with respect to the bottom wall 212 to the top wall 222. The load transmission member 320 is made of a synthetic resin or the like. As shown in FIG. 4, the load transmission member 320 is disposed between a pair of intermediate plates 103 adjacent to each other in the orthogonal direction.

[0029] As shown in FIGS. 2 and 3, the load transmission member 320 has a transmission member main body 320A and a pair of positioning members 320B. The transmission member main body 320A has a first column portion 321, a second column portion 322, and a connecting portion 323.

[0030] The first column portion 321 is disposed on the cross member 310. The upper end portion of the first column portion 321 may be in contact with the ceiling wall 222 or may be spaced apart from the ceiling wall 222. As shown in FIG. 3, a first engaging portion 321a is provided at the lower end portion of the first column portion 321, and the first engaging portion 321a is attached to a first mounting hole (not shown) provided on the upper surface of the cross member 310. In FIG. 3, the first engaging portion 321a should actually be shown by a dashed line but is shown by a solid line.

[0031] The second column portion 322 is disposed on the cross member 310. The second column portion 322 is disposed at a position spaced apart from the first column portion 321 in one direction. The upper end portion of the second column portion 322 may be in contact with the ceiling wall 222 or may be spaced apart from the ceiling wall 222. As shown in FIG. 3, a second engaging portion 322a is provided at the lower end portion of the second column portion 322, and the second engaging portion 322a is attached to a second mounting hole (not shown) provided on the upper surface of the cross member 310. In FIG. 3, the second engaging portion 322a should actually be shown by a dashed line but is shown by a solid line.

[0032] The connecting portion 323 connects the first column portion 321 and the second column portion 322. As shown in FIGS. 3 and 4, the connecting portion 323 is disposed between a pair of intermediate plates 103 adjacent to each other in the orthogonal direction. The connecting portion 323 is provided with a through hole 323h penetrating the connecting portion 323 in the orthogonal direction.

[0033] Each positioning member 320B is located within the through-hole 323h of the connecting portion 323 and is fixed to the connecting portion 323. By contacting a pair of power storage stacks 100 that are adjacent to each other in the orthogonal direction with the transmission member body 320A interposed therebetween, each positioning member 320B determines the position of the transmission member body 320A between these power storage stacks 100. As shown in FIG. 3, each positioning member 320B has a central portion 326 and a contact portion 327.

[0034] As shown in FIGS. 3 and 5, the central portion 326 sandwiches the connecting portion 323.

[0035] The contact portion 327 is connected to the upper end portion of the central portion 326. The contact portion 327 is compressibly deformable in the orthogonal direction (the left-right direction in FIG. 4). Specifically, the contact portion 327 has a shape that gradually curves upward and convex downward as it separates from the central portion 326 in the orthogonal direction. The contact portion 327 is supported by the central portion 326 in a cantilever beam shape. The contact portion 327 is in contact with a pair of power storage stacks 100 that are adjacent to each other in the orthogonal direction in a state of being compressed in the orthogonal direction. The contact portion 327 receives a load input in the orthogonal direction with respect to the peripheral walls 214 and 224.

[0036] As described above, in the power storage device 1 of the present embodiment, when a downward load is input to the top wall 222, the load is transmitted to the bottom wall 212 via the protection structure 300, and when an upward load is input to the bottom wall 212, the load is transmitted to the top wall 222 via the protection structure 300. Therefore, it is suppressed that a load input in the vertical direction to the case 200 is transmitted to the power storage cell 110.

[0037] Furthermore, since the load transmission member 320 has the contact portion 327 that contacts the pair of power storage stacks 100 in a compressed state, it is suppressed that the load transmission member 320 is relatively displaced with respect to the power storage stack 100 and the cross member 310 due to vibration or the like. For this reason, the generation of abnormal noise due to the load transmission member 320 colliding with the power storage stack 100 or the cross member 310 is suppressed.

[0038] In addition, by inserting the first engaging portion 321a and the second engaging portion 322a into the respective mounting holes of the cross member 310, the assembly of the load transmission member 320 to the cross member 310 is completed, so that the assembly of the load transmission member 320 to the cross member 310 becomes easy. Further, the centering in the orthogonal direction during the assembly of the load transmission member 320 becomes easy.

[0039] It is understood by those skilled in the art that the above-described exemplary embodiments are specific examples of the following aspects.

[0040] The power storage device in the above embodiment includes a plurality of power storage cells arranged so as to be aligned in one direction, and a plurality of power storage stacks arranged so as to be aligned in an orthogonal direction orthogonal to both the one direction and the vertical direction, a case for housing the plurality of power storage stacks, and a protection structure provided in the case for protecting the plurality of power storage cells from a load input in the vertical direction with respect to the case. The case has a bottom wall disposed below the plurality of power storage stacks, a top wall disposed above the plurality of power storage stacks, and a peripheral wall connecting a peripheral edge of the bottom wall and a peripheral edge of the top wall and surrounding the plurality of power storage stacks. The protection structure includes a cross member disposed on the bottom wall and between a pair of the power storage stacks adjacent to each other in the orthogonal direction, having a shape extending in the one direction and connected to the peripheral wall, and a load transmission member disposed on the cross member. The load transmission member is compressibly deformable in the orthogonal direction and has at least one contact portion that contacts a pair of the power storage stacks adjacent to each other in the orthogonal direction in a compressed state.

[0041] In this power storage device, when a downward load is input to the top wall, the load is transmitted to the bottom wall through the protection structure, and when an upward load is input to the bottom wall, the load is transmitted to the top wall through the protection structure. Therefore, the load input in the vertical direction with respect to the case is suppressed from being transmitted to the power storage cells.

[0042] Furthermore, since the load transfer member has a contact portion that contacts the pair of power storage stacks in a compressed state, relative displacement of the load transfer member with respect to the power storage stacks and the cross member due to vibration or the like is suppressed. For this reason, generation of abnormal noise due to the load transfer member colliding with the power storage stacks or the cross member is suppressed.

[0043] Also, the length of the protection structure in the vertical direction is preferably greater than the length of the plurality of power storage cells in the vertical direction.

[0044] Also, it is preferable that the at least one contact portion includes a pair of contact portions arranged at positions spaced apart from each other in the one direction.

[0045] Also, it is preferable that the load transfer member further includes a first column portion, a second column portion arranged at a position spaced apart from the first column portion in the one direction, and a connecting portion that connects the first column portion and the second column portion.

[0046] In this aspect, it becomes possible to transfer a vertical load at positions spaced apart from each other in one direction by the first column portion and the second column portion. Furthermore, since the first column portion and the second column portion are connected by the connecting portion, the handling of the load transfer member becomes easier compared to the case where the first column portion and the second column portion are configured as separate members.

[0047] Also, it is preferable that the at least one contact portion is connected to the connecting portion.

[0048] It should be noted that the embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of claims rather than the description of the above embodiments, and further includes all modifications within the meaning and scope equivalent to the scope of claims.

Explanation of Reference Numerals

[0049] 1 Energy storage device, 100 Energy storage stack, 101 First unit stack, 102 Second unit stack, 103 Intermediate plate, 110 Energy storage cell, 200 Case, 210 Lower case, 212 Bottom wall, 212a Protrusion, 214 Lower surrounding wall, 216 Lower flange, 220 Upper case, 222 Top wall, 224 Upper surrounding wall, 226 Upper flange, 300 Protection structure, 310 Cross member, 320 Load transmission member, 320A Transmission member main body, 320B Positioning member, 321 First column portion, 321S First outer surface, 322 Second column portion, 322S Second outer surface, 323 Connecting portion, 326 Central portion, 327 Contact portion.

Claims

1. including a plurality of power storage cells arranged side by side in one direction, and a plurality of power storage stacks arranged side by side in a direction orthogonal to both the one direction and the vertical direction; a case for housing the plurality of power storage stacks; a protection structure provided in the case for protecting the plurality of power storage cells from a load input in the vertical direction with respect to the case, and the case includes a bottom wall disposed below the plurality of power storage stacks; a top wall disposed above the plurality of power storage stacks; a peripheral wall connecting a peripheral edge of the bottom wall and a peripheral edge of the top wall and surrounding the plurality of power storage stacks; the protection structure includes a cross member disposed between a pair of the power storage stacks adjacent to each other in the orthogonal direction on the bottom wall, having a shape extending in the one direction and connected to the peripheral wall; a load transmission member disposed on the cross member, and the load transmission member is compressibly deformable in the orthogonal direction and has at least one contact portion that contacts a pair of the power storage stacks adjacent to each other in the orthogonal direction in a compressed state; a length of the protection structure in the vertical direction is greater than a length of the plurality of power storage cells in the vertical direction; the at least one contact portion includes a pair of contact portions disposed at positions spaced apart from each other in the one direction, a power storage device.

2. the load transmission member includes a first column portion; a second column portion disposed at a position spaced apart from the first column portion in the one direction; and a connecting portion connecting the first column portion and the second column portion, the power storage device according to claim 1.

3. the at least one contact portion is connected to the connecting portion, the power storage device according to claim 2.

Images