Power storage device

Abstract

To provide a power storage device that allows a reduction in mass of a restraint member.SOLUTION: A power storage device 1 include a plurality of power storage modules 100, a conductive member 200, a pair of restraint members 300, and an adhesive member 400. Each power storage module includes an overlapping region R10 that overlaps with the pair of restraint members in a stacking direction, and a non-overlapping region R20 that does not overlap with the pair of restraint members in the stacking direction. Each power storage module 100 includes a direct contact region R1 that is in direct contact with the conductive member, and an indirect contact region R2 that is in contact with the power storage module adjacent to that power storage module or the conductive member, with the adhesive member 400 interposed therebetween. The overlapping region R10 includes the direct contact region R1, and the non-overlapping region R20 includes the indirect contact region R2.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to an electricity storage device. [Background technology]

[0002] JP 2019-216073 A discloses an energy storage device including an energy storage module stack configured by stacking a plurality of energy storage modules via conductive plates, and a restraining section that applies a restraining load to the energy storage module stack. The restraining section has a pair of restraining plates that sandwich the energy storage module stack in the stacking direction. The restraining plates are rectangular plates having an area slightly larger than the areas of the energy storage modules and the conductive plates when viewed from the stacking direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-216073 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the energy storage device described in JP 2019-216073 A, the larger the electrodes in the energy storage module, the larger the device as a whole becomes, and the increase in mass of the restraint portion in particular becomes significant.

[0005] An object of the present disclosure is to provide an electricity storage device that allows for a reduction in the mass of a restraining member. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, an energy storage device includes a plurality of stacked energy storage modules, each of which includes a plurality of stacked electrodes; a conductive member provided between a pair of adjacent energy storage modules and which connects the pair of energy storage modules; a pair of restraining members which restrain the plurality of energy storage modules and the conductive member from both sides in a stacking direction of the plurality of energy storage modules; and an adhesive member which bonds the energy storage module and the conductive member, wherein the plurality of energy storage modules have overlapping regions which overlap with the pair of restraining members in the stacking direction and non-overlapping regions which do not overlap with the pair of restraining members in the stacking direction, and each energy storage module has a direct contact region in direct contact with the conductive member and an indirect contact region in contact with the storage module adjacent to the storage module or the conductive member via the adhesive member, wherein the overlapping region includes the direct contact region and the non-overlapping region includes the indirect contact region. Effect of the Invention

[0007] According to the present disclosure, it is possible to provide an electricity storage device that allows the mass of a restraining member to be reduced. [Brief description of the drawings]

[0008] [Figure 1] 1 is a perspective view illustrating a schematic configuration of an electricity storage device according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Diagram 3] FIG. 2 is a cross-sectional view illustrating a bipolar electrode. [Figure 4] FIG. 2 is a cross-sectional view illustrating a monopolar electrode. [Diagram 5] FIG. 11 is a cross-sectional view that illustrates a schematic modification of the electricity storage device. [Figure 6] FIG. 13 is a perspective view showing a schematic modification of the restraining member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure will now be described with reference to the accompanying drawings, in which the same or corresponding components are designated by the same reference numerals.

[0010] Fig. 1 is a perspective view showing a schematic diagram of an energy storage device according to an embodiment of the present disclosure. Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1. As shown in Figs. 1 and 2, the energy storage device 1 includes a plurality of energy storage modules 100, a plurality of conductive members 200, a pair of restraining members 300, an adhesive member 400, and an elastic member 500.

[0011] The multiple energy storage modules 100 are stacked on one another. In the example shown in Fig. 2, the multiple energy storage modules 100 include four energy storage modules 100. The outer shape of each energy storage module 100 in a plan view is formed into a rectangular shape. Each energy storage module 100 includes multiple stacked electrodes.

[0012] Each electrode may be formed of a bipolar electrode 110 shown in Fig. 3. The bipolar electrode 110 has a current collecting foil 111, a positive electrode active material layer 112 provided on one surface of the current collecting foil 111, and a negative electrode active material layer 113 provided on the other surface of the current collecting foil 111. In this case, the electricity storage module 100 is formed by alternately stacking the bipolar electrodes 110 and the separators 130.

[0013] Alternatively, each electrode may be formed of a monopolar electrode 120 as shown in Fig. 4. The positive or negative monopolar electrode 120 has a current collecting foil 121 and an active material layer 122 provided on the current collecting foil. In this case, the power storage module 100 is formed by stacking the positive monopolar electrode 120 and the negative monopolar electrode 120 with a separator 130 interposed therebetween.

[0014] As shown in Figs. 2 to 4, the outermost surface of each power storage module 100 in the stacking direction of the multiple electrodes is formed of an electrode.

[0015] Each conductive member 200 is provided between a pair of adjacent power storage modules 100. Each conductive member 200 electrically connects the pair of power storage modules 100. In the example shown in Fig. 2, the plurality of conductive members 200 includes five conductive members 200. In this embodiment, the plurality of conductive members 200 includes two coolers 210 and three conductive plates 220.

[0016] Each cooler 210 is disposed between the storage module 100 disposed on the outermost side in the stacking direction (the vertical direction in FIG. 2 ) of the multiple storage modules 100 and the storage module 100 adjacent to the storage module 100. A flow path through which a cooling liquid (such as water) can flow is provided within the cooler 210.

[0017] The current-carrying plates 220 are disposed below the lowest power storage module 100, above the highest power storage module 100, and between the power storage module 100 stacked in the second layer from the bottom and the power storage module 100 stacked in the third layer from the bottom. Each current-carrying plate 220 may be formed in a flat plate shape.

[0018] The pair of restraining members 300 restrain the plurality of power storage modules 100 and the conductive members 200 from both sides in the stacking direction. The pair of restraining members 300 includes a lower restraining member 310 and an upper restraining member 320.

[0019] The lower restraining member 310 supports the multiple energy storage modules 100 from below. In this embodiment, the lower restraining member 310 is configured by the bottom of a lower case 315 that houses the multiple energy storage modules 100. The outer shape of the bottom in a plan view is larger than the outer shape of the energy storage modules 100 in a plan view. As shown in FIG. 2, the energy storage device 1 has an upper case 330 that houses the multiple energy storage modules 100 together with the lower case 315. Note that the upper case 330 is not shown in FIG. 1.

[0020] The upper restraining member 320 is disposed above the multiple power storage modules 100. The upper restraining member 320 restrains the peripheral edges of the multiple power storage modules 100 in a plan view. As shown in Fig. 1, the upper restraining member 320 is formed in a quadrangular ring shape.

[0021] As shown in Fig. 2, the multiple energy storage modules 100 have overlapping regions R10 and non-overlapping regions R20. The overlapping regions R10 are regions that overlap with the pair of restraining members 300 in the stacking direction. In this embodiment, the overlapping regions R10 are substantially configured as regions that overlap with the upper restraining member 320 in the stacking direction. The non-overlapping regions R20 are regions that do not overlap with the pair of restraining members 300 in the stacking direction. Note that in Fig. 2, the overlapping regions R10 are indicated by dashed lines, and the non-overlapping regions R20 are indicated by dashed lines.

[0022] In this embodiment, the cooler 210 has a central portion 212 formed in the non-overlapping region R20. The current-carrying plate 220 has a central portion 222 formed in the non-overlapping region R20.

[0023] The adhesive member 400 bonds the power storage module 100 and the conductive member 200. The adhesive member 400 may be made of a conductive adhesive material or an insulating adhesive material.

[0024] The elastic member 500 is provided between the power storage module 100 that is arranged outermost in the stacking direction among the multiple power storage modules 100, and at least one of the pair of restraining members 300. As shown in Fig. 2, the elastic member 500 is provided between the uppermost power storage module 100 and the upper restraining member 320. More specifically, the elastic member 500 is provided between the current-carrying plate 220 on the uppermost power storage module 100 and the upper restraining member 320. The elastic member 500 is preferably formed into a shape that fits within the overlapping region R10.

[0025] 2, each energy storage module 100 has a direct contact region R1 and an indirect contact region R2. The direct contact region R1 is a region of the energy storage module 100 that directly contacts the conductive member 200. The indirect contact region R2 is a region of the energy storage module 100 that contacts an adjacent energy storage module 100 or a conductive member 200 via an adhesive member 400.

[0026] The overlapping region R10 includes the direct contact region R1. In this embodiment, the overlapping region R10 includes only the direct contact region R1. However, the overlapping region R10 may also include a part of the indirect contact region R2. Also, a part of the direct contact region R1 may be formed in the non-overlapping region R20.

[0027] The non-overlapping region R20 includes the indirect contact region R2. In this embodiment, the non-overlapping region R20 includes only the indirect contact region R2. However, the non-overlapping region R20 may include a part of the direct contact region R1. Also, a part of the indirect contact region R2 may be formed in the overlapping region R10.

[0028] As described above, the energy storage device 1 in this embodiment has the non-overlapping region R20, which reduces the mass of the restraining member 300 and also reduces the overall outer shape of the energy storage device 1. Furthermore, the overlapping region R10 includes the direct contact region R1, which ensures conduction between a pair of adjacent energy storage modules 100, and the non-overlapping region R20 includes the indirect contact region R2, which effectively fixes the pair of adjacent energy storage modules 100 to each other.

[0029] 5, the conductive member 200 does not have to have the central portions 212, 222. In this case, the adjacent power storage modules 100 are in contact with each other via the adhesive member 400 in the non-overlapping region R20.

[0030] As shown in FIG. 6, a pair of restraining members 300 may restrain the four corners of each power storage module 100.

[0031] It will be appreciated by those skilled in the art that the exemplary embodiments and examples described above are examples of the following aspects.

[0032] [Aspect 1] a plurality of stacked storage modules, each of the plurality of storage modules including a plurality of stacked electrodes; a conductive member provided between a pair of the power storage modules adjacent to each other and electrically connecting the pair of the power storage modules; a pair of restraining members that restrain the plurality of power storage modules and the conductive member from both sides in a stacking direction of the plurality of power storage modules; an adhesive member that adheres the power storage module and the conductive member, The plurality of power storage modules include an overlapping region overlapping the pair of restraining members in the stacking direction; a non-overlapping region that does not overlap with the pair of restraining members in the stacking direction, Each storage module is a direct contact area that directly contacts the conductive member; an indirect contact region that contacts the adjacent power storage module or the conductive member via the adhesive member; the overlap region includes the direct contact region; The non-overlapping region includes the indirect contact region.

[0033] In this energy storage device, since the non-overlapping region is provided, it is possible to reduce the mass of the restraining member or the overall external dimensions of the energy storage device. Furthermore, since the overlapping region includes a direct contact region, electrical continuity between a pair of adjacent energy storage modules is ensured, and since the non-overlapping region includes an indirect contact region, the pair of adjacent energy storage modules is effectively fixed to each other.

[0034] [Aspect 2] 2. The power storage device of claim 1, wherein the overlap region includes only the direct contact region.

[0035] In this embodiment, electrical continuity between a pair of adjacent power storage modules is more reliably ensured.

[0036] [Aspect 3] 3. The power storage device according to aspect 1 or 2, wherein the pair of restraining members restrain peripheral portions of the power storage modules in a plan view.

[0037] In this embodiment, even if the area of ​​each power storage module is increased, the mass of the restraining member or the overall external dimensions of the power storage device are reduced.

[0038] [Aspect 4] Each of the energy storage modules is formed in a rectangular shape in a plan view, 3. The power storage device according to aspect 1 or 2, wherein the pair of restraining members restrain four corners of each power storage module.

[0039] In this embodiment, even if the area of ​​each power storage module is increased, the mass of the restraining member or the overall external dimensions of the power storage device are reduced.

[0040] [Aspect 5] The energy storage device of any one of aspects 1 to 4, further comprising an elastic member provided between an outermost energy storage module in the stacking direction among the plurality of energy storage modules and at least one of the pair of restraining members.

[0041] In this embodiment, the restraining load applied by the restraining member can be adjusted by the elastic member.

[0042] It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be considered as limiting. The scope of the present invention is indicated by the claims, not by the description of the embodiments above, and further includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0043] 1 Energy storage device, 100 Energy storage module, 110 Bipolar electrode, 120 Monopolar electrode, 200 Conductive member, 210 Cooler, 220 Current-carrying plate, 300 Restraint member, 310 Lower restraint member, 315 Lower case, 320 Upper restraint member, 330 Upper case, 400 Adhesive member, 500 Elastic member, R1 Direct contact area, R2 Indirect contact area, R10 Overlap area, R20 Non-overlap area.

Claims

1. a plurality of stacked storage modules, each of the plurality of storage modules including a plurality of stacked electrodes; a conductive member provided between a pair of the power storage modules adjacent to each other and electrically connecting the pair of the power storage modules; a pair of restraining members that restrain the plurality of power storage modules and the conductive member from both sides in a stacking direction of the plurality of power storage modules; an adhesive member that adheres the power storage module and the conductive member, The plurality of power storage modules include an overlapping region overlapping the pair of restraining members in the stacking direction; a non-overlapping region that does not overlap with the pair of restraining members in the stacking direction, Each storage module is a direct contact area that directly contacts the conductive member; an indirect contact region that contacts the adjacent power storage module or the conductive member via the adhesive member; the overlap region includes the direct contact region; The non-overlapping region includes the indirect contact region.

2. The power storage device according to claim 1 , wherein the overlapping region includes only the direct contact region.

3. The power storage device according to claim 1 , wherein the pair of restraining members restrain peripheral portions of the power storage modules in a plan view.

4. Each of the energy storage modules is formed in a rectangular shape in a plan view, The power storage device according to claim 1 , wherein the pair of restraining members restrain four corners of each power storage module.

5. The energy storage device according to claim 1 , further comprising an elastic member provided between an outermost energy storage module in the stacking direction among the plurality of energy storage modules and at least one of the pair of restraining members.

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