Energy storage module

Abstract

To provide a power storage module capable of limiting the number of storage cells affected by heat conduction from a heat-generating storage cell while avoiding the increase in size.SOLUTION: A battery pack 1 includes a plurality of power storage cells 100 arranged to be lined along one direction, a case 200 that accommodates the plurality of power storage cells, and a plurality of partition members 300 that partitions between a pair of power storage cells adjacent to each other. Each partition member 300 of the plurality of partition members has an energizing part 320 for energizing the power storage cells 100 in contact with the partition member in a direction to be separated from the partition member 300. Each of the partition members 300 is melted at a predetermined temperature.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] For example, International Publication No. 2020 / 137062 discloses a power supply device including a plurality of battery cells and a separator disposed between adjacent battery cells. The separator has a heat insulating sheet and a molded member having higher shape stability than the heat insulating sheet.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the power supply device described in International Publication No. 2020 / 137062, in order to ensure heat insulation between cells, it is necessary to increase the thickness of the heat insulating sheet. As the thickness of the heat insulating sheet increases, the entire device becomes larger.

[0005] An object of the present disclosure is to provide a power storage module capable of limiting the number of power storage cells affected by heat conduction from a heat-generating power storage cell while avoiding an increase in size.

Means for Solving the Problems

[0006] A power storage module according to an aspect of the present disclosure includes a plurality of power storage cells arranged side by side in one direction, a case that houses the plurality of power storage cells, and a plurality of partition members that partition between a pair of adjacent power storage cells. Each of the plurality of partition members has a biasing portion that biases a power storage cell in contact with the partition member in a direction away from the partition member, and each of the partition members melts at a predetermined temperature.

Advantages of the Invention

[0007] According to the present disclosure, it is possible to provide a power storage module capable of limiting the number of power storage cells affected by heat conduction from a heated power storage cell while avoiding an increase in size.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Modes 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 given the same numbers.

[0010] FIG. 1 is a plan view schematically showing a part of a power storage module according to an embodiment of the present disclosure. This power storage module 1 is mounted on a vehicle, for example.

[0011] As shown in FIG. 1, the power storage module 1 of the present embodiment includes a plurality of power storage cells 100, a case 200, and a plurality of partition members 300.

[0012] The plurality of power storage cells 100 are arranged side by side in one direction (the left-right direction in FIG. 1). The plurality of power storage cells 100 include five or more power storage cells 100. Each power storage cell 100 is formed in a rectangular parallelepiped shape. Each power storage cell 100 is formed flat.

[0013] The case 200 houses a plurality of power storage cells 100. The case 200 is formed of resin or metal. As shown in FIG. 2, the case 200 has a case body 201 and a lid portion 250. Note that in FIG. 1, the illustration of the lid portion 250 is omitted.

[0014] As shown in FIGS. 1 and 2, the case body 201 has a shape that opens upward. The case body 201 has a bottom wall 210 and a pair of side walls 220.

[0015] The bottom wall 210 is disposed below each power storage cell 100. The bottom wall 210 supports each power storage cell 100.

[0016] The pair of side walls 220 are disposed on both sides of the plurality of power storage cells 100 in the orthogonal direction (the vertical direction in FIG. 1) that is orthogonal to both the one direction and the vertical direction. As shown in FIG. 2, each side wall 220 has a shape that stands up from the edge of the bottom wall 210 in the orthogonal direction (the left - right direction in FIG. 2).

[0017] The lid portion 250 closes the opening of the case body 201. The lid portion 250 is connected to the upper end portions of the pair of side walls 220.

[0018] Each partition member 300 partitions between a pair of adjacent power storage cells 100. The plurality of partition members 300 includes four or more partition members 300. Each partition member 300 is made of a thermoplastic resin. Each partition member 300 melts at a predetermined temperature. The predetermined temperature is set to the temperature when the power storage cell 100 generates heat due to overcharge or the like. Each partition member 300 has a partition wall 310, a biasing portion 320, and a rib 330.

[0019] The partition wall 310 partitions between a pair of adjacent power storage cells 100. The partition wall 310 is fixed to the case 200. More specifically, the lower end portion of the partition wall 310 is fixed to the bottom wall 210, and the side end portion of the partition wall 310 is fixed to the side wall 220. The partition wall 310 is formed in a flat plate shape.

[0020] The biasing portion 320 biases the power storage cell 100 in contact with the partitioning member 300 including the biasing portion 320 in a direction away from the partitioning member 300. The biasing portion 320 is attached to the surface of the partitioning wall 310 in one direction. The biasing portion 320 is made of an elastic material that can be elastically deformed in one direction. The biasing portion 320 may be formed of a material different from the material forming the partitioning wall 310 (for example, a material that melts at a temperature slightly lower than the predetermined temperature), as long as it is a material that melts at at least the predetermined temperature. The biasing portion 320 is disposed between the partitioning wall 310 and the power storage cell 100 in a compressed state in one direction. As shown in FIG. 2, the biasing portion 320 is formed in a rectangular shape.

[0021] The rib 330 is provided on the partitioning wall 310. More specifically, the rib 330 is fixed to the edge of the surface of the partitioning wall 310 facing the power storage cell 100 in one direction. The rib 330 is fixed to the inner surface of the case 200. As shown in FIG. 1, the distance between a pair of ribs 330 disposed at positions sandwiching the power storage cell 100 in one direction is equal to the dimension of each power storage cell 100 in one direction. For this reason, when each power storage cell 100 is inserted between a pair of partitioning members 300, the power storage cell 100 is effectively guided by the rib 330. The rib 330 may be formed of the same material as the material forming the partitioning wall 310.

[0022] As shown in FIG. 2, the rib 330 has a lower rib 331, a side rib 332, and an upper rib 333.

[0023] The lower rib 331 is disposed between the biasing portion 320 and the bottom wall 210. The lower rib 331 is fixed to the partitioning wall 310 and the bottom wall 210. The lower rib 331 has a shape extending in the orthogonal direction.

[0024] The side rib 332 is disposed between the biasing portion 320 and the side wall 220. The side rib 332 is fixed to the partition wall 310 and the side wall 220. The side rib 332 has a shape extending in the vertical direction. As shown in FIGS. 1 and 2, the length between a pair of side ribs 332 facing each other in the orthogonal direction is smaller than the length of the power storage cell 100 in the orthogonal direction.

[0025] The upper rib 333 is positioned between the biasing portion 320 and the lid portion 250. The upper rib 333 is fixed to the partition wall 310 and the lid portion 250. The upper rib 333 has a shape extending in the orthogonal direction.

[0026] Next, with reference to FIG. 3, in the power storage module 1 described above, a case where a specific power storage cell 100 (hereinafter referred to as "trigger cell 101") among the plurality of power storage cells 100 generates heat will be described.

[0027] When the trigger cell 101 generates heat up to a predetermined temperature due to overcharging or the like, a pair of partition members 300 (partition wall 310, biasing portion 320, and rib 330) in contact with the trigger cell 101 melt. As a result, spaces are formed on both sides of the trigger cell 101 in one direction.

[0028] Then, among the plurality of power storage cells 100, a power storage cell 100 adjacent to the trigger cell 101 (hereinafter referred to as "adjacent cell 102") is biased in a direction approaching the trigger cell 101 by the biasing portion 320 in contact with the adjacent cell 102, as indicated by the arrow in FIG. 3. At this time, the reaction force acting on the biasing portion 320 is received by the partition wall 310 and the rib 330 fixed to the case 200.

[0029] As a result, the distance D between the power storage cell 100 (hereinafter referred to as "second adjacent cell 103") disposed on the side opposite to the side where the trigger cell 101 is located with respect to the adjacent cell 102 among the plurality of power storage cells 100 increases. That is, an air layer (heat insulating layer) is formed between the adjacent cell 102 and the second adjacent cell 103. Even when the plurality of power storage cells 100 are constrained from both sides in one direction, the constraint load acting on the partition wall 310 between the second adjacent cell 103 and the adjacent cell 102 from the second adjacent cell 103 is received by the partition wall 310 and the rib 330. For this reason, the second adjacent cell 103 is prevented from approaching the adjacent cell 102.

[0030] As described above, in this power storage module 1, it is possible to limit the number of power storage cells 100 affected by the heat conduction from the heated power storage cell 100 (trigger cell 101) while avoiding an increase in the size of the entire device.

[0031] In the above-described embodiment, an example in which the biasing portion 320 is attached to the surface of the partition wall 310 in one direction has been described. However, the biasing portion 320 may be attached to the side surface of the power storage cell 100 in one direction by adhesion or the like.

[0032] Further, after the partition member 300 melts, since the distance between the trigger cell 101 and the adjacent cell 102 and the distance between the adjacent cell 102 and the second adjacent cell 103 change, the bus bar connecting the external terminals of a pair of adjacent power storage cells 100 is preferably stretchable in one direction.

[0033] Further, the partition member 300 may not be fixed to the case 200. That is, the partition member 300 may be relatively movable in one direction with respect to the case 200.

[0034] Those skilled in the art will understand that the above-described exemplary embodiments are specific examples of the following aspects.

[0035] The power storage module in the above-described embodiment includes a plurality of power storage cells arranged side by side along one direction, a case that houses the plurality of power storage cells, and a plurality of partition members that partition between a pair of adjacent power storage cells. Each of the plurality of partition members has a biasing portion that biases the power storage cell in contact with the partition member in a direction away from the partition member, and each of the partition members melts at a predetermined temperature.

[0036] In this power storage module, when a specific power storage cell among the plurality of power storage cells generates heat up to a predetermined temperature due to overcharging or the like, a pair of partition members in contact with the specific power storage cell melt. As a result, spaces are formed on both sides of the specific power storage cell in one direction. Then, an adjacent cell, which is a power storage cell adjacent to the specific power storage cell among the plurality of power storage cells, is biased in a direction approaching the specific power storage cell by a biasing portion in contact with the adjacent cell. Thereby, the distance between the second adjacent cell, which is a power storage cell arranged on the side opposite to the side where the specific power storage cell is located with respect to the adjacent cell among the plurality of power storage cells, and the adjacent cell increases. That is, an air layer (heat insulation layer) is formed between the adjacent cell and the second adjacent cell. Therefore, in this power storage module, it is possible to limit the number of power storage cells affected by heat conduction from the power storage cell that has generated heat while avoiding an increase in the size of the entire device.

[0037] Further, each of the partition members is fixed to the case, further has a partition wall that partitions between a pair of adjacent power storage cells, the biasing portion is made of an elastic material that can be elastically deformed in the one direction, and is preferably disposed between the partition wall and the power storage cell in a state compressed in the one direction.

[0038] In this way, when the biasing portion elastically returns, the reaction force acting on the biasing portion from the power storage cell is received by the partition wall, so that the power storage cell is effectively displaced relative to the case.

[0039] In this case, each of the partition members is preferably provided on the surface of the partition wall in the one direction and further has a rib fixed to the case.

[0040] By doing so, the reaction force acting on the biasing portion by the partition wall and the rib can be more reliably received.

[0041] Further, the case has a bottom wall disposed below the plurality of power storage cells, and a pair of side walls disposed on both sides of the plurality of power storage cells in a direction orthogonal to both the one direction and the vertical direction, and the rib is preferably a lower rib disposed between the biasing portion and the bottom wall, and a side rib disposed between the biasing portion and the side wall.

[0042] Further, it is preferable that the distance between the pair of ribs disposed at positions sandwiching the power storage cell in the one direction is equal to the dimension of each power storage cell in the one direction.

[0043] By doing so, when the power storage cell is inserted between the pair of partition members of each power storage cell, the power storage cell is effectively guided by the rib.

[0044] 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 shown 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

[0045] 1 Power storage module, 100 Power storage cell, 200 Case, 201 Case body, 210 Bottom wall, 220 Side wall, 250 Lid portion, 300 Partition member, 310 Partition wall, 320 Biasing portion, 330 Rib, 331 Lower rib, 332 Side rib, 333 Upper rib.

Claims

1. A plurality of power storage cells arranged to be aligned along one direction, A case for housing the plurality of power storage cells, A plurality of partition members for partitioning between a pair of adjacent power storage cells, and The case has a bottom wall disposed below the plurality of power storage cells, and a pair of side walls disposed on both sides of the plurality of power storage cells in a direction orthogonal to both the one direction and the vertical direction, Each of the plurality of partition members has a partition wall fixed to the case and partitioning between a pair of adjacent power storage cells, is made of an elastic material that is elastically deformable in the one direction, and has a biasing portion disposed between the partition wall and the power storage cell in a state of being compressed in the one direction, and a rib provided at an edge of a surface of the partition wall facing the power storage cell in the one direction, The biasing portion biases the power storage cell in contact with the biasing portion in a direction away from the partition wall, A lower end portion of the partition wall is fixed to the bottom wall, and a side end portion of the partition wall is fixed to the side wall, The rib has a lower rib disposed between the biasing portion and the bottom wall and fixed to the bottom wall, and a side rib disposed between the biasing portion and the side wall and fixed to the side wall, The partition wall, the biasing portion, and the rib of each of the partition members are a power storage module that melts at a predetermined temperature.

2. The lower rib is also fixed to the partition wall, and the side rib is also fixed to the partition wall. The power storage module according to claim 1.

3. The case further has a lid portion connected to upper end portions of the pair of side walls, and the rib further has an upper rib disposed between the biasing portion and the lid portion, The above rib is fixed to the partition wall and the lid portion. The power storage module according to claim 1 or 2.

4. The distance between the pair of ribs disposed at positions sandwiching the power storage cell in the one direction is equal to the dimension of each power storage cell in the one direction. The power storage module according to any one of claims 1 to 3.

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