Power storage device

Abstract

To provide a power storage device capable of reducing a crash stroke while avoiding an increase in the size of a vehicle.SOLUTION: A power storage device includes at least one power storage module 100 including a power storage stack 110 including a plurality of power storage cells 101 arranged in a line along one direction, and a pair of end plates 120, frame portions 222 arranged on both sides of the power storage module in the one direction, a cross member 230 arranged adjacent to the power storage module in the perpendicular direction and having a shape extending along the one direction, and a connecting member 300 connecting the frame portion and the cross member and connecting the frame portion and the end plate.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] Conventionally, a power storage device mounted on a vehicle or the like is known. For example, JP 2021-172136 A discloses a battery pack including a plurality of battery modules, and a tray and a cover for accommodating the plurality of battery modules. Each battery module has a battery stack consisting of a laminate in which a plurality of battery cells are stacked, and a pair of end plates fixed to both sides of the battery stack. The plurality of battery cells are arranged to be aligned along the width direction of the vehicle. The plurality of battery modules are arranged to be aligned along the front-rear direction of the vehicle. The tray has a bottom plate, four side plates surrounding the plurality of battery modules, and a battery cross member arranged between a pair of battery modules adjacent to each other in the front-rear direction. The battery cross member has a shape extending in the width direction and is connected to a side plate arranged on the right side and a side plate arranged on the left side in the width direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-172136 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a battery pack such as that described in JP 2021-172136 A, it is required to increase the number of storage cells, but in order to do so, it is necessary to reduce the crash stroke (the stroke for absorbing the impact load without damaging the storage cells) when an impact load is input in the arrangement direction of each storage cell. In order to reduce the crash stroke, it is necessary to increase the strength of cross members, etc., which increases the size of the vehicle.

[0005] An object of the present disclosure is to provide an electricity storage device that can reduce the crash stroke while avoiding an increase in the size of a vehicle. [Means for solving the problem]

[0006] A storage device according to one aspect of the present disclosure comprises at least one storage module including a storage stack including a plurality of storage cells arranged in a line along one direction, and a pair of end plates arranged on either side of the storage stack in the one direction, a frame portion arranged on either side of the at least one storage module in the one direction, a cross member arranged adjacent to the at least one storage module in a perpendicular direction perpendicular to both the one direction and the up-down direction, and having a shape extending along the one direction, and a connecting member connecting the frame portion and the cross member and connecting the frame portion and the end plate. Effect of the Invention

[0007] According to the present disclosure, it is possible to provide an electricity storage device that can reduce the crash stroke while avoiding an increase in the size of a vehicle. [Brief description of the drawings]

[0008] [Figure 1] 1 is an exploded perspective view illustrating a schematic configuration of a portion of an electricity storage device according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a perspective view of the electricity storage module. [Diagram 3] FIG. 4 is a perspective view showing a state before the storage module is fixed to the case. [Figure 4] FIG. 2 is a perspective view showing a state in which the electricity storage module is fixed to the case. [Diagram 5] FIG. 5 is a cross-sectional view of VV in FIG. [Figure 6] 13A and 13B are diagrams illustrating schematic diagrams of modified examples of the connection 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] 1 is an exploded perspective view that illustrates a schematic configuration of a power storage device according to an embodiment of the present disclosure, the power storage device 1 being mounted on a vehicle such as an electric car.

[0011] As shown in Fig. 1, the energy storage device 1 includes a plurality of energy storage modules 100, a case 200, and a connection member 300. Only two energy storage modules 100 are shown in Fig. 1. It is to be noted that the energy storage device 1 may include only a single energy storage module 100.

[0012] As shown in FIG. 2, each energy storage module 100 includes an energy storage stack 110, a pair of end plates 120, and a restraining band 130.

[0013] The power storage stack 110 includes a plurality of power storage cells 101 arranged to line up along one direction. In this embodiment, the power storage stack 110 includes 24 power storage cells 101. However, the number of power storage cells 101 is not limited to this. For example, each power storage cell 101 may be a lithium ion battery. Each power storage cell 101 is formed in a rectangular parallelepiped. Each power storage cell 101 is formed to be flat. As shown in FIG. 1, the multiple power storage modules 100 are arranged to line up in an orthogonal direction that is orthogonal to both one direction and the vertical direction.

[0014] In this embodiment, the power storage stack 110 has an intermediate plate 102. The intermediate plate 102 is disposed between a pair of power storage cells 101 disposed in the center among the multiple power storage cells 101. That is, the power storage stack 110 has 12 power storage cells 101 disposed on one side of the intermediate plate 102 and 12 power storage cells 101 disposed on the other side of the intermediate plate 102.

[0015] The pair of end plates 120 are disposed on both sides of the electricity storage stack 110 in one direction. Each end plate 120 is made of metal (aluminum, etc.). As shown in FIGS. 2 to 5, each end plate 120 has a plate body 122 and a protrusion 124.

[0016] The plate body 122 faces the electricity storage stack 110 in one direction. The plate body 122 is formed in a substantially flat plate shape.

[0017] The protruding portion 124 has a shape that protrudes outward in one direction from the plate body 122. As shown in Figures 2 and 3, the protruding portion 124 is formed with an insertion hole 124h through which a fastening member B1 (see Figure 4) such as a bolt can be inserted.

[0018] The restraint bands 130 restrain the electricity storage stack 110 from both sides in one direction. As shown in FIGS. 2 to 4, the restraint bands 130 have a pair of side restraint portions 132, a lower restraint portion 134, and an upper restraint portion 136.

[0019] Each side restraint portion 132 is disposed on a side of the power storage stack 110 in the orthogonal direction. Each side restraint portion 132 is made of metal or the like. As shown in Fig. 1 and Fig. 2, each side restraint portion 132 has a restraint portion main body 132a and a flange portion 132b.

[0020] The restraining portion main body 132a restrains the electricity storage stack 110 from both sides in one direction. The restraining portion main body 132a has a shape extending from one end of the electricity storage stack 110 to the other end in one direction. The restraining portion main body 132a is formed in a flat plate shape. The restraining portion main body 132a covers the side of the electricity storage stack 110 in the orthogonal direction. An insulating sheet may be disposed between the restraining portion main body 132a and the electricity storage stack 110. As shown in FIGS. 2 to 5, the restraining portion main body 132a is connected to the side of the plate main body 122 by a fastening member B32.

[0021] 1 and 2, the flange portion 132b has a shape that protrudes outward in the perpendicular direction from the restraint portion main body 132a. The flange portion 132b is connected to a cross member 230, which will be described later.

[0022] The lower restraining portion 134 is disposed below the power storage stack 110, and restrains the power storage stack 110 from both sides in one direction. The lower restraining portion 134 has a shape extending from one end of the power storage stack 110 to the other end in one direction. The lower restraining portion 134 is disposed below the power storage stack 110 and in the center of the power storage stack 110 in the perpendicular direction. The lower restraining portion 134 is made of metal or the like. An insulating sheet may be disposed between the lower restraining portion 134 and the lower surface of the power storage stack 110. The lower restraining portion 134 is connected to the lower surface of the plate body 122 by a fastening member not shown.

[0023] The upper restraining portion 136 is disposed above the power storage stack 110 and restrains the power storage stack 110 from both sides in one direction. The upper restraining portion 136 has a shape extending from one end of the power storage stack 110 to the other end in one direction. The upper restraining portion 136 is disposed above the power storage stack 110 and in the center of the power storage stack 110 in the perpendicular direction. The upper restraining portion 136 is provided with an exposure port for exposing the pressure release valve of each power storage cell 101. The upper restraining portion 136 is made of metal or the like. An insulating sheet may be disposed between the upper restraining portion 136 and the lower surface of the power storage stack 110. As shown in FIG. 2 and FIG. 3, the upper restraining portion 136 is connected to the upper surface of the plate main body 122 by a fastening member B36.

[0024] The case 200 houses a plurality of power storage modules 100. The case 200 has a lower case 200L and an upper case 200U (see FIG. 5). Note that the upper case 200U is not shown in FIG.

[0025] The lower case 200L has a shape that opens upward. The lower case 200L is made of a metal such as aluminum. The lower case 200L has a bottom wall 210, a peripheral wall 220, and a cross member 230.

[0026] The bottom wall 210 supports from below the multiple power storage modules 100. The bottom wall 210 may be formed in a flat plate shape.

[0027] The peripheral wall 220 stands up from the peripheral edge of the bottom wall 210 and surrounds the multiple power storage modules 100. The peripheral wall 220 includes a frame portion 222.

[0028] The frame portions 222 are disposed on both sides of the power storage module 100 in one direction. The frame portions 222 have a shape extending in an orthogonal direction. As shown in Fig. 5, the frame portion 222 is formed in a hollow shape having a closed cross section. The frame portion 222 is formed by, for example, extrusion molding of aluminum. The frame portion 222 may be fixed to the bottom wall 210 by welding, fastening, or the like. An upper surface 222S of the frame portion 222 is formed flat.

[0029] The cross member 230 is disposed at a position adjacent to the power storage module 100 in the perpendicular direction. The cross member 230 has a shape extending along one direction. As shown in FIG. 1, the cross member 230 separates a pair of power storage modules 100 adjacent to each other in the perpendicular direction. As shown in FIG. 5, both ends of the cross member 230 in one direction are in contact with the inner side surfaces of the frame portion 222. That is, the cross member 230 has a function of reinforcing the frame portion 222.

[0030] As shown in Fig. 5, the cross member 230 has an upper wall 232. The upper wall 232 has an upper surface 232S formed flush with an upper surface 222S of the frame portion 222. As shown in Fig. 5, the flange portion 132b of the side restraint portion 132 is connected to the upper wall 232 by a fastening member B10. An insertion hole 232h through which a fastening member B3 can be inserted is formed at an end portion of the upper wall 232 in one direction.

[0031] The connection member 300 connects the frame portion 222 and the cross member 230, and also connects the frame portion 222 and the end plate 120. The connection member 300 connects each of the end plates 120 and the frame portion 222 of a pair of power storage modules 100 adjacent to each other in the perpendicular direction. As shown in FIG. 3, the connection member 300 has a first arm portion 310, a second arm portion 320, and a cross connection portion 330.

[0032] The first arm 310 connects the protrusion 124 of the end plate 120 of one of a pair of adjacent power storage modules 100 and the frame portion 222. The first arm 310 has a shape extending in a perpendicular direction. As shown in FIG. 3, the first arm 310 is provided with an insertion hole 310h through which a fastening member B1 (see FIG. 4) can be inserted. The fastening member B1 is fixed to the frame portion 222 in a state where it is inserted through the insertion hole 124h formed in the protrusion 124 and the insertion hole 310h formed in the first arm 310.

[0033] The second arm 320 connects the protruding portion 124 of the end plate 120 of the other of the pair of power storage modules 100 and the frame portion 222. The second arm 320 has a shape extending in a perpendicular direction. As shown in FIG. 3, the second arm 320 is provided with an insertion hole 320h through which a fastening member B2 (see FIG. 4) can be inserted. The fastening member B2 is fixed to the frame portion 222 in a state where it is inserted through the insertion hole 124h formed in the protruding portion 124 and the insertion hole 320h formed in the second arm 320.

[0034] The cross connection portion 330 connects the cross member 230 and the frame portion 222. The cross connection portion 330 is formed between the first arm portion 310 and the second arm portion 320. The cross connection portion 330 has a shape extending in one direction. The cross connection portion 330, the first arm portion 310, and the second arm portion 320 are formed on the same plane. The first arm portion 310, the second arm portion 320, and the cross connection portion 330 are formed in a substantially T-shape. As shown in FIG. 3, the cross connection portion 330 is provided with an insertion hole 330h through which the fastening member B3 (see FIG. 4 and FIG. 5) can be inserted. The fastening member B3 is fixed to the upper wall 232 of the cross member 230 in a state where it is inserted through the insertion hole 330h formed in the cross connection portion 330 and the insertion hole 232h (see FIG. 5) formed in the upper wall 232 of the cross member 230.

[0035] In the energy storage device 1 described above, when an impact load is input to the frame portion 222 from a pole P (see FIGS. 4 and 5) provided on the structure 250 arranged on the outside of the frame portion 222 in one direction, the connection member 300 transmits the impact load to the cross member 230 and the end plate 120. Specifically, the impact load is transmitted to the cross member 230 via the cross connection portion 330, and is transmitted to the end plate 120 of each energy storage module 100 via the first arm portion 310 and the second arm portion 320. The load transmitted to the end plate 120 is transmitted to the restraining band 130. That is, in this energy storage device 1, the cross member 230 and the energy storage module 100 bear the impact load, so that the crash stroke is reduced. Therefore, it is possible to increase the number of energy storage cells 101 mounted while avoiding an increase in the size of the vehicle.

[0036] In the above embodiment, since the flange portion 132b of the side restraint portion 132 is connected to the cross connection portion 330, the impact load transmitted to the cross member 230 via the cross connection portion 330 is transmitted to the restraint portion main body 132a via the flange portion 132b. When the cross member 230 and the side restraint portion 132 can bear the impact load, the connection member 300 may be composed of only the cross connection portion 330.

[0037] In the above embodiment, the multiple connection members 300 may be connected to each other. For example, as shown in Fig. 6, the connection member 300 may have a connection portion 340 that connects a second arm portion 320 (represented as "320A" in Fig. 6) arranged on one side of one power storage module 100 in the orthogonal direction to a first arm portion 310 (represented as "310B" in Fig. 6) arranged on the other side of the one power storage module 100 in the orthogonal direction.

[0038] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0039] [Aspect 1] At least one energy storage module including: an energy storage stack including a plurality of energy storage cells arranged in a line along one direction; and a pair of end plates arranged on both sides of the energy storage stack in the one direction; frame portions disposed on both sides of the at least one power storage module in the one direction; a cross member disposed adjacent to the at least one power storage module in a direction perpendicular to both the one direction and the up-down direction, and having a shape extending along the one direction; a connecting member that connects the frame portion and the cross member and also connects the frame portion and the end plate.

[0040] In this energy storage device, when an external impact load is applied in the direction in which the energy storage cells are arranged (the one direction), the connection members transmit the impact load to the cross members and the end plates. In other words, in this energy storage device, the cross members and the energy storage modules bear the impact load, thereby reducing the crash stroke.

[0041] [Aspect 2] the at least one power storage module includes a pair of power storage modules arranged at positions sandwiching the cross member in the perpendicular direction, 2. The energy storage device according to aspect 1, wherein the connection member connects the end plate and the frame portion of each of the pair of energy storage modules.

[0042] In this embodiment, the transmission path of the impact load is increased, so that the crash stroke is further reduced.

[0043] [Aspect 3] Each of the pair of power storage modules further includes a restraining band that restrains the power storage stack from both sides in the one direction; 3. The power storage device according to aspect 2, wherein the restraint band is connected to the end plate.

[0044] In this embodiment, the impact load input to the frame portion is transmitted to the restraint bands via the connection members and the end plates. In other words, the restraint bands in the energy storage module mainly bear the impact load, so that it is possible to reduce the crash stroke while suppressing the transmission of the impact load to each energy storage cell.

[0045] [Aspect 4] The end plate is a plate body facing the electricity storage stack in the one direction; a protruding portion having a shape protruding outward from the plate body in the one direction, the connecting member connects the protruding portion and the frame portion, 4. The power storage device of aspect 3, wherein the restraint band is connected to the plate body.

[0046] [Aspect 5] The connecting member is a first arm portion that connects the protruding portion of the end plate of one of the pair of power storage modules to the frame portion; a second arm portion that connects the protruding portion of the end plate of the other of the pair of energy storage modules to the frame portion; a cross connection portion formed between the first arm portion and the second arm portion, the cross member connecting the cross member and the frame portion.

[0047] [Aspect 6] The cross member has an upper surface formed flush with the frame portion, 6. The power storage device according to aspect 5, wherein the cross connection portion, the first arm portion, and the second arm portion are formed on the same plane.

[0048] 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]

[0049] 1 Energy storage device, 100 Energy storage module, 101 Energy storage cell, 110 Energy storage stack, 120 End plate, 122 Plate body, 124 Protrusion, 130 Restraint band, 132 Side restraint portion, 132a Restraint portion body, 132b Flange portion, 134 Lower restraint portion, 136 Upper restraint portion, 200 Case, 200L Lower case, 200U Upper case, 210 Bottom wall, 220 Peripheral wall, 222 Frame portion, 222S Upper surface, 230 Cross member, 232 Upper wall, 232S Upper surface, 300 Connection member, 310 First arm portion, 320 Second arm portion, 330 Cross connection portion, 340 Connection portion, P Pole.

Claims

1. At least one energy storage module including: an energy storage stack including a plurality of energy storage cells arranged in a line along one direction; and a pair of end plates arranged on both sides of the energy storage stack in the one direction; frame portions disposed on both sides of the at least one power storage module in the one direction; a cross member disposed adjacent to the at least one power storage module in a direction perpendicular to both the one direction and the up-down direction, and having a shape extending along the one direction; a connecting member that connects the frame portion and the cross member and also connects the frame portion and the end plate, the at least one power storage module includes a pair of power storage modules arranged at positions sandwiching the cross member in the perpendicular direction, the connection member connects each of the end plates of the pair of power storage modules to the frame portion, Each of the pair of power storage modules further includes a restraining band that restrains the power storage stack from both sides in the one direction; The restraint band is connected to the end plate.

2. The end plate is a plate body facing the electricity storage stack in the one direction; a protruding portion having a shape protruding outward from the plate body in the one direction, the connecting member connects the protruding portion and the frame portion, The power storage device according to claim 1 , wherein the restraining band is connected to the plate body.

3. The connecting member is a first arm portion connecting the protruding portion of the end plate of one of the pair of power storage modules to the frame portion; a second arm portion that connects the protruding portion of the end plate of the other of the pair of energy storage modules to the frame portion; The power storage device according to claim 2 , further comprising a cross connection portion formed between the first arm portion and the second arm portion, the cross member being connected to the frame portion.

4. The cross member has an upper surface formed flush with the frame portion, The power storage device according to claim 3 , wherein the cross connection portion, the first arm portion, and the second arm portion are formed on the same plane.

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