Power storage module and power storage device

Abstract

The invention relates to a power storage module and a power storage device. The power storage module includes a first stack and a second stack arranged alternately in a first direction, the first stack including a plurality of first unit cells arranged in the first direction, and the second stack including a plurality of second unit cells arranged in a vertical direction orthogonal to the first direction.

Description

Technical Field

[0001] The present disclosure relates to a power storage module and a power storage device including the power storage module. Background Art

[0002] As a conventional power storage module, a configuration in which a plurality of unit cells are arranged in a predetermined one direction is disclosed in International Publication No. 2020 / 134054. Summary of the Invention

[0003] In a configuration in which a plurality of unit cells are arranged in one direction as in International Publication No. 2020 / 134054, the side surfaces of the unit cells having the largest area are arranged in the first direction. When a predetermined unit cell generates heat, the side surface expands in the first direction, and heat is sequentially transferred to the unit cells from the side closer to the first unit cell 211 that generates heat to the side farther from the first unit cell 211 that generates heat. As a result, it is possible to transfer heat to a large range in the first direction to a plurality of unit cells.

[0004] The present disclosure has been made in view of the above problems, and an object of the present disclosure is to provide a power storage module and a power storage device including the power storage module that can suppress heat transfer to the entire power storage module when a predetermined unit cell generates heat.

[0005] The power storage module according to the present disclosure includes a first laminate and a second laminate that are alternately arranged in the first direction. The first laminate includes a plurality of first unit cells arranged in the first direction. The second laminate includes a plurality of second unit cells arranged in the up-and-down direction orthogonal to the first direction.

[0006] Generally, when a unit cell generates heat, the central portion (abdomen) of the unit cell expands and heat is transferred to an adjacent unit cell.

[0007] According to the above configuration, by alternately arranging the first laminate and the second laminate having different lamination directions, it is possible to make the orientation of the abdomen of the first unit cell included in the first laminate different from the orientation of the abdomen of the second unit cell included in the second laminate. As a result, heat transfer between the first laminate and the second laminate can be suppressed.

[0008] In the power storage module based on the present disclosure described above, it is possible that the first laminate is arranged at both ends in the first direction in the first laminate and the second laminate alternately arranged in the first direction.

[0009] According to the above configuration, the first laminate in which the abdomens of the first unit cells are arranged in the first direction is arranged at both ends in the first direction, so that heat can be easily dissipated to the outside in the first direction.

[0010] The electricity storage device based on the present disclosure includes the above-described electricity storage module and a cooler that cools the above-described first laminate and the above-described second laminate.

[0011] According to the above configuration, the cooler can cool the first laminate and the second laminate.

[0012] In the electricity storage device based on the present disclosure, it is possible that the cooler is arranged to meander in the vertical direction while passing through any gap in the gap between the first laminate and the second laminate and extend in the first direction.

[0013] According to the above configuration, by arranging the cooler to meander in the vertical direction and extend in the first direction, it is possible to cool the upward or downward facing surfaces of the second unit cells included in the second laminate laminated in the vertical direction using the cooler. In addition, it is also possible to cool the surfaces of the first unit cells facing any direction in the first direction using the cooler.

[0014] In the electricity storage device based on the above present disclosure, it is possible that each of the first laminate and the second laminate includes a plurality of side surfaces arranged around an axis orthogonal to the first direction and the vertical direction. In this case, it is possible that the cooler is meanderingly arranged to cool two of the plurality of side surfaces of the first laminate and two of the plurality of side surfaces of the second laminate.

[0015] According to the above configuration, by arranging the cooler in a meandering manner, it is possible to cool the first laminate and the second laminate substantially uniformly. Thereby, it is possible to suppress the generation of heat distribution in the first laminate and the second laminate.

[0016] The above and other objects, features, aspects, and advantages of the present invention will become apparent from the following detailed description of the present invention understood in association with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of a vehicle equipped with the electricity storage device of Embodiment 1.

[0018] Figure 2 It is a diagram showing a state where the electricity storage device of Embodiment 1 is fixed to a vehicle.

[0019] Figure 3 It is a schematic exploded perspective view of the electricity storage device of Embodiment 1.

[0020] Figure 4 It is a schematic perspective view showing the electricity storage module and the cooler in the electricity storage device of Embodiment 1.

[0021] Figure 5 This is a schematic diagram showing the movement of heat in the case of predetermined unit cell heating in the energy storage module of Embodiment 1.

[0022] Figure 6 This is a schematic diagram showing the movement of heat in the case of predetermined unit cell heating in the energy storage module of the comparative mode.

[0023] Figure 7 This is a schematic diagram when observing the energy storage module and the cooler from one side in the second direction in the energy storage device of Embodiment 2.

[0024] Figure 8 This is a schematic plan view when observing the energy storage module and the cooler from above in the energy storage device of Embodiment 2. Detailed Embodiments

[0025] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, in the embodiments shown below, the same or common parts are denoted by the same reference numerals in the drawings, and their description will not be repeated.

[0026] (Embodiment 1)

[0027] Figure 1 This is a schematic diagram of a vehicle equipped with the energy storage device of Embodiment 1. Figure 2 This is a diagram showing the situation where the energy storage device of Embodiment 1 is fixed to the vehicle. Refer to Figure 1 and Figure 2 , the vehicle 1 of Embodiment 1 will be described.

[0028] The vehicle 1 is a hybrid vehicle capable of traveling using the power of at least one of a motor and an engine, or an electric vehicle that travels by using the driving force obtained from electric energy.

[0029] The vehicle 1 includes a vehicle body 2, front wheels 3, rear wheels 4, and an energy storage device 10. The vehicle body 2 includes a frame member 5. The energy storage device 10 has an upper surface 10a. This upper surface 10a also functions as a floor member that defines the vehicle interior.

[0030] The frame member 5 includes a pair of side members 6 and a pair of side sills 7. The pair of side sills 7 are arranged on both end sides in the width direction of the vehicle 1. The pair of side members 6 are arranged inside the pair of side sills 7 at a distance. The pair of side members 6 and the pair of side sills 7 extend along the front-rear direction of the vehicle 1.

[0031] A pair of longitudinal beams 6 are separated in the width direction of the vehicle 1. The main body 35 of the power storage device 10 is disposed in the gap between the pair of longitudinal beams 6. A gap is provided between the main body 35 and the pair of longitudinal beams 6. Thus, even when a side collision occurs to the vehicle 1, the impact input to the power storage device 10 can be suppressed.

[0032] Fixed portions 36 are provided on both side surfaces of the main body 35 in the width direction of the vehicle 1. The fixed portions 36 are fixed to the pair of longitudinal beams 6 by fastening connection members 8.

[0033] The frame member 5 further includes a transverse member 9. The transverse member 9 is disposed above the power storage device 10 so as to span from one sill 7 to the other sill 7. The upper surface 10a of the power storage device 10 is fixed to the transverse member 9.

[0034] In addition, in the above description, an example is illustrated in which the frame member 5 includes a pair of longitudinal beams 6 and a pair of sills 7, but it is not limited thereto. A pair of sills 7 may also have the functions of a pair of longitudinal beams 6. In this case, the pair of longitudinal beams 6 can be omitted, and the above-described fixed portions 36 can also be fixed to the pair of sills 7.

[0035] Figure 3 It is a schematic exploded perspective view of the power storage device of Embodiment 1. Refer to Figure 3 , and the detailed configuration of the power storage device 10 will be described.

[0036] The power storage device 10 includes a plurality of power storage modules 20, a housing case 30, a partition member 40, and a cooler 50 (refer to Figure 4 ).

[0037] The plurality of power storage modules 20 are arranged and disposed in a second direction (DR2 direction) orthogonal to the first direction (DR1 direction) and the vertical direction. In addition, the vertical direction is orthogonal to the first direction. The first direction is parallel to the left-right direction of the vehicle 1, for example, in the mounted state where the power storage device 10 is mounted on the vehicle 1. The second direction is parallel to the front-rear direction of the vehicle 1 in the above-mounted state. The vertical direction is parallel to the vertical direction and parallel to the up-down direction of the vehicle 1.

[0038] The power storage module 20 includes a plurality of unit cells. Busbar modules are respectively provided on one side and the other side of the power storage module 20 in the first direction, and the plurality of unit cells are connected in series through the busbar modules. In addition, the plurality of power storage modules 20 are also connected in series.

[0039] The housing case 30 includes an upper member 31 and a lower member 32. The lower member 32 has a substantially box-shaped form that opens upward. The lower member 32 includes a main body portion 35 and a fixed portion 36. The main body portion 35 has a bottom wall portion 321, a first wall portion 322, a second wall portion 323, and side wall portions 324, 325. The first wall portion 322, the second wall portion 323, and the side wall portions 324, 325 are provided so as to stand up from the periphery of the bottom wall portion 321.

[0040] The first wall portion 322 and the second wall portion 323 face each other in the second direction. The side wall portions 324, 325 face each other in the first direction. The fixed portion 36 is provided on the outer surfaces of the side wall portions 324, 325.

[0041] The partition member 40 is provided so as to partition the accommodation space inside the housing case 30. Specifically, the partition member 40 is provided so as to extend in the first direction and divides the accommodation space of the housing case 30 in the second direction. The partition member 40 divides the area where the power storage module 20 is disposed. The power storage modules 20 are respectively disposed in the areas partitioned by the partition member 40.

[0042] The upper member 31 has a substantially flat plate shape. The upper member 31 covers the plurality of power storage modules 20 and closes the open space of the lower member 32. A sealing member may be filled in the gap between the upper member 31 and the power storage module 20. The sealing member may have insulation properties.

[0043] Figure 4 It is a schematic perspective view of the power storage module and the cooler in the power storage device according to Embodiment 1.

[0044] As Figure 4 shown, the power storage module 20 includes a plurality of first stacked bodies 21 and a plurality of second stacked bodies 22. The number of the first stacked bodies 21 and the second stacked bodies 22 can be appropriately set according to the size of the vehicle 1. In addition, the number of the first stacked bodies 21 and the second stacked bodies 22 is not limited to a plurality, and may be a single one.

[0045] The plurality of first stacked bodies 21 and the plurality of second stacked bodies 22 are alternately arranged in the first direction. The first stacked body 21 includes a plurality of first unit cells 211 arranged in the first direction. The second stacked body 22 includes a plurality of second unit cells 212 arranged in the vertical direction.

[0046] The first unit cell 211 and the second unit cell 212 have a long strip shape with the second direction as the length direction. The first unit cell 211 has a flat rectangular parallelepiped shape with a thickness in the first direction. The second unit cell 212 has a flat rectangular parallelepiped shape with a thickness in the vertical direction.

[0047] The first unit cell 211 and the second unit cell 212 can be composed of the same unit cell. In this case, the number of components can be reduced and the manufacturing cost can be lowered. In addition, "the same" also means including manufacturing errors such as tolerances. Alternatively, the first unit cell 211 and the second unit cell 212 can be composed of different unit cells.

[0048] The first unit cell 211 and the second unit cell 212 are, for example, secondary batteries such as nickel-metal hydride batteries or lithium-ion batteries. The first unit cell 211 and the second unit cell 212 can use a liquid electrolyte or a solid electrolyte. The first unit cell 211 and the second unit cell 212 can also be rechargeable capacitors.

[0049] The first unit cell 211 and the second unit cell 212 each have a first end face and a second end face on one side and the other side in the second direction. The first end faces of the first unit cell 211 and the second unit cell 212 face the side wall portion 324. The second end faces of the first unit cell 211 and the second unit cell 212 face the side wall portion 325.

[0050] The first stacked body 21 is disposed at both ends of the power storage module 20 in the first direction. That is, in the first stacked body 21 and the second stacked body 22 alternately arranged in the first direction, the first stacked body 21 is disposed at both ends in the first direction. In such a case, the center portion (abdomen) of the side face having the largest area in the first unit cell 211 described later is exposed in the gap between the side wall portions 324 and 325, so that heat is easily dissipated to the outside in the first direction. Thereby, the heat dissipation performance of the power storage module 20 can be improved.

[0051] The cooler 50 is disposed, for example, below the power storage module 20. The cooler 50 is arranged to be able to cool the power storage module 20. Specifically, for example, a refrigerant flow path for flowing a refrigerant for cooling the power storage module 20 is provided inside the cooler 50. The cooler 50 has a shape that expands in a plane direction orthogonal to the vertical direction. Alternatively, the cooler 50 can also be disposed above the power storage module 20.

[0052] The cooler 50 can be in direct contact with the power storage module 20 or can be in thermal contact with the power storage module 20 via a highly thermally conductive heat conduction member. The heat conduction member can be an adhesive containing a silicone-based resin, an acrylic-based resin, a polyurethane resin, or an epoxy resin.

[0053] Figure 5 It is a schematic diagram showing the movement of heat in the case where a predetermined unit cell in the power storage module of Embodiment 1 generates heat.

[0054] As Figure 5As shown, in the first stack 21, the sides of the first unit cell 211 with the largest area are arranged in the first direction. On the other hand, in the second stack 22, the sides of the second unit cell 212 with the largest area are arranged in the vertical direction.

[0055] When the unit cell generates heat, the central part (abdomen) of the side with the largest area expands in the thickness direction (the first direction in the first unit cell 211 and the vertical direction in the second unit cell 212), thereby transferring heat to the adjacent unit cells.

[0056] In the present embodiment, by alternately arranging the first stack 21 and the second stack 22 with different stacking directions, it is possible to make the orientation of the abdomen of the first unit cell 211 included in the first stack 21 different from the orientation of the abdomen of the second unit cell 212 included in the second stack 22.

[0057] Therefore, when the first unit cell 211 in the predetermined first stack 21 generates heat (when generating heat at the position shown by F in the figure), in this first stack 21, heat is transferred as shown by the arrow AR1. However, the abdomen of the first unit cell 211 arranged at both ends in the first direction does not approach the abdomen of the second unit cell 212 of the second stack 22, but approaches the side with a small area in the second unit cell 212. Thereby, heat transfer from the first stack 21 to the second stack 22 is suppressed. Moreover, since the abdomen of the second stack 22 faces the vertical direction, it is difficult for heat to be transferred from the second stack 22 to the first unit cell 211 located at a position on the side opposite to the first stack 21 including the first unit cell 211 that generates heat. In this way, heat transfer can be suppressed between the first stack 21 and the second stack 22, and heat transfer to the entire power storage module 20 can be suppressed.

[0058] (Comparative method)

[0059] Figure 6 It is a schematic diagram showing the movement of heat when a predetermined unit cell generates heat in the power storage module of the comparative method. Refer to Figure 6 and explain the movement of heat in the power storage module 20X of the comparative method.

[0060] As Figure 6As shown, the power storage module 20X of the comparison method does not include the second laminate 22 and is formed by arranging a plurality of first unit cells 211 in the first direction. In such a case, among the plurality of first unit cells 211, the sides of the first unit cell 211 having the largest area are continuously arranged in the first direction. Therefore, when a predetermined first unit cell 211 generates heat (when generating heat at the position shown by F in the figure), heat is transferred sequentially from the side closer to the heat-generating first unit cell 211 to the first unit cell 211 located on the side farther from the heat-generating first unit cell 211 via the side having the largest area as indicated by the arrow AR2. Thus, in the comparison method, heat transfer to the entire power storage module 20X is easier than in Embodiment 1.

[0061] (Embodiment 2)

[0062] Figure 7 is a schematic view when observing the power storage module and the cooler from one side in the second direction in the power storage device of Embodiment 2. Figure 8 is a schematic plan view when observing the power storage module and the cooler from above in the power storage device of Embodiment 2. Refer to Figure 7 and Figure 8 , the power storage device 10A of Embodiment 2 will be described.

[0063] As Figure 7 and Figure 8 shown, in the case where the power storage device 10A of Embodiment 2 is compared with the power storage device 10 of Embodiment 1, the configuration of the cooler 50A is different. Other configurations are substantially the same.

[0064] The first laminate 21 includes a plurality of sides 21a, 21b, 21c, 21d arranged around an axis orthogonal to the first direction (DR1 direction) and the vertical direction. In addition, the axis orthogonal to the first direction and the vertical direction is parallel to the second direction. Sides 21a, 21b face each other in the vertical direction, and sides 21c, 21d face each other in the first direction.

[0065] The second laminate 22 includes a plurality of sides 22a, 22b, 22c, 22d arranged around an axis orthogonal to the first direction and the vertical direction. Sides 22a, 22b face each other in the vertical direction, and sides 22c, 22d face each other in the first direction.

[0066] The cooler 50A is meanderingly arranged in such a manner as to cool two sides out of the plurality of sides 21a, 21b, 21c, 21d of the first stack 21 and two sides out of the plurality of sides 22a, 22b, 22c, 22d of the second stack 22. The two sides mentioned above refer to sides that are orthogonal to each other. The sides 21c, 21d are constituted by the sides with the largest area among the sides of the first unit cell 211. The sides 22a, 22b are constituted by the sides with the largest area among the sides of the second unit cell 212.

[0067] The cooler 50A has a plurality of first cooling portions 51, a plurality of second cooling portions 52, and a plurality of third cooling portions 53. The first cooling portions 51, the second cooling portions 52, and the third cooling portions 53 are arranged so as to extend in the second direction. Refrigerant flow paths through which refrigerant can flow are provided in the first cooling portions 51, the second cooling portions 52, and the third cooling portions 53, and the refrigerant flows in each cooling portion as indicated by the arrows in Figure 8 the figure.

[0068] The plurality of first cooling portions 51 are arranged at intervals in the first direction. The first stack 21 and the second stack 22 are arranged between two adjacent first cooling portions 51 in the first direction. The first cooling portion 51 is arranged in the gap so as to skip one of the gaps between the plurality of first stacks 21 and second stacks 22 arranged in the first direction. The first cooling portion 51 cools the side 21c of the first stack 21 and the side 22d of the second stack 22.

[0069] The plurality of second cooling portions 52 are arranged above the first stack 21 and the second stack 22. The plurality of third cooling portions 53 are arranged below the first stack 21 and the second stack 22. The plurality of second cooling portions 52 and the plurality of third cooling portions 53 are arranged such that two second cooling portions 52 and two third cooling portions 53 are alternately arranged vertically along the first direction.

[0070] By arranging the cooler 50A in a meandering manner in this way, the first stack 21 and the second stack 22 can be cooled substantially uniformly. Thereby, it is possible to suppress the generation of thermal distribution within the first stack 21 and the second stack 22.

[0071] In addition, in the above description, the case where the cooler 50A is meanderingly arranged so as to cool both side surfaces of the first stacked body 21 and both side surfaces of the second stacked body 22 is illustrated, but it is not limited thereto. The cooler may be arranged in such a way that it meanders in the vertical direction while passing through any one of the gaps between the first stacked body 21 and the second stacked body 22 and extends in the first direction. Thereby, the cooler can cool the upward or downward facing surfaces of the second unit cells 212 included in the second stacked body 22 stacked in the vertical direction. In addition, the cooler can also cool the surfaces of the first unit cells 211 facing any direction in the first direction.

[0072] For example, the first cooling portions 51 may be respectively arranged in the gaps between the mutually adjacent first stacked body 21 and the second stacked body 22, and the cooler may be meanderingly arranged so as to cool three of the plurality of side surfaces 21a, 21b, 21c, 21d of the first stacked body 21 and three of the plurality of side surfaces 22a, 22b, 22c, 22d of the second stacked body 22. In this case, the first stacked body 21 and the second stacked body 22 can also be cooled substantially uniformly.

[0073] (Other modification examples)

[0074] In the above-described Embodiments 1 and 2, the case where the first direction in which the first stacked body 21 and the second stacked body 22 are alternately arranged is parallel to the width direction of the vehicle 1 is illustrated, but it is not limited thereto. The above-mentioned first direction may also be parallel to the left-right direction of the vehicle 1 in the above-described mounted state. In this case, the above-mentioned second direction is parallel to the front-rear direction of the vehicle 1 in the above-described mounted state.

[0075] The embodiments of the present invention have been described, but it should be considered that the disclosed embodiments are illustrative in all respects and not restrictive. The scope of the present invention is shown by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A power storage module, The power storage module includes a first laminate and a second laminate alternately arranged in a first direction. The first laminate includes a plurality of first unit cells arranged along the first direction. The second laminate includes a plurality of second unit cells arranged along the up-and-down direction orthogonal to the first direction.

2. The power storage module according to claim 1, In the first laminate and the second laminate alternately arranged in the first direction, the first laminate is arranged at both ends in the first direction.

3. A power storage device, The power storage device includes the power storage module according to claim 1 or 2 and a cooler for cooling the first laminate and the second laminate.

4. The power storage device according to claim 3, The cooler is arranged to meander in the up-and-down direction while passing through any of the gaps between the first laminate and the second laminate and extend in the first direction.

5. The power storage device according to claim 4, Each of the first laminate and the second laminate includes a plurality of side surfaces arranged around an axis orthogonal to the first direction and the up-and-down direction. The cooler is meanderingly arranged to cool two of the plurality of side surfaces of the first laminate and two of the plurality of side surfaces of the second laminate.

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