Power storage device

Abstract

To provide a power storage device capable of discharging gas discharged from a power storage stack to the outside of a housing case while reducing a decrease in rigidity of the housing case.SOLUTION: A power storage device 10 includes a first power storage stack 21 and a second power storage stack 22, an electrical device 70, and a housing case 30. The housing case 30 is provided with case-side discharge valves 41, 42 capable of discharging gas discharged into the housing case 30. The first power storage stack 21 and the second power storage stack 22 are arranged side by side at an interval in a first direction. The electrical device 70 is arranged in a clearance G between the first power storage stack 21 and the second power storage stack 22, and a space S where the gas discharged from the first power storage stack 21 or the gas discharged from the second power storage stack 22 can flow is provided in the clearance G between the first power storage stack 21 and the second power storage stack 22.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to an electric storage device mounted on a vehicle. [Background technology]

[0002] As a conventional electricity storage device, JP2022-516519A (Patent Document 1) discloses a structure in which a portion of a housing case for housing a plurality of electricity storage stacks is formed from a hollow member, and the hollow portion of the hollow member is used as a flow path for gas discharged from the electricity storage stacks. A number of intake holes are provided in the bottom wall or side wall of the housing case for introducing the gas into the flow path. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2022-516519 Summary of the Invention [Problem to be solved by the invention]

[0004] However, as disclosed in Patent Document 1, when a large number of air intake holes are provided in the bottom wall or side wall of the storage case, there is a concern that the rigidity of the storage case may decrease.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and an object of the present disclosure is to provide an energy storage device that can exhaust gas discharged from the energy storage stack to the outside of the storage case while suppressing a decrease in the rigidity of the storage case. [Means for solving the problem]

[0006] A power storage device according to the present disclosure includes a first power storage stack and a second power storage stack, an electric device for controlling the first power storage stack and the second power storage stack, and a housing case that houses the first power storage stack, the second power storage stack, and the electric device. The housing case is provided with a case-side exhaust valve that can exhaust gas discharged into the housing case. The first power storage stack and the second power storage stack are arranged side by side at a distance from each other in a first direction. The electric device is arranged in a gap between the first power storage stack and the second power storage stack. The gap between the first power storage stack and the second power storage stack is provided with a space through which the gas discharged from the first power storage stack or the gas discharged from the second power storage stack can flow.

[0007] According to the above configuration, gas discharged from the first power storage stack and / or the second power storage stack can be discharged to the outside from the case-side exhaust valve through the gap between the first power storage stack and the second power storage stack in which the electrical equipment is arranged. This eliminates the need to provide the housing case with multiple holes for introducing gas from each power storage stack into the exhaust path, thereby maintaining good rigidity of the housing case.

[0008] In the power storage device according to the present disclosure, the storage case may have a bottom wall and a peripheral wall connected to the bottom wall, and the case-side exhaust valve may be provided in a portion of the peripheral wall facing the gap between the first power storage stack and the second power storage stack.

[0009] According to the above configuration, gas discharged into the space between the first and second power storage stacks can be discharged to the outside of the housing case in the shortest possible time, thereby preventing the first and second power storage stacks from being heated by the gas.

[0010] In the energy storage device according to the present disclosure, the first energy storage stack may include a plurality of first unit cells arranged in a second direction perpendicular to the first direction, and the second energy storage stack may include a plurality of second unit cells arranged in the second direction. Each of the plurality of first unit cells may be provided with a first exhaust valve capable of discharging the gas toward the second energy storage stack. Each of the plurality of second unit cells may be provided with a second exhaust valve capable of discharging the gas toward the first energy storage stack.

[0011] According to the above configuration, gas from the first power storage stack and the second power storage stack can be directly discharged into the space portion.

[0012] In the power storage device according to the present disclosure, the electric device may be disposed at a position not overlapping with the plurality of first exhaust valves and the plurality of second exhaust valves in the first direction.

[0013] According to the above configuration, it is possible to prevent gas from the first power storage stack and the second power storage stack from blowing directly onto the electronic device.

[0014] In the power storage device according to the present disclosure, the electrical device may include a battery ECU and a junction box. The battery ECU may be disposed in the gap at a center portion in a second direction perpendicular to the first direction. The junction box may be disposed alongside the battery ECU in the second direction.

[0015] According to the above configuration, gas tends to accumulate at both end portions in the second direction in the gap between the first power storage stack and the second power storage stack. By disposing the battery ECU in the center in the second direction, it is possible to prevent the battery ECU from being heated by the accumulated gas.

[0016] The energy storage device based on the present disclosure may further include a straightening plate disposed in the gap and directing gas from the first energy storage stack or gas from the second energy storage stack toward both outsides of the electrical equipment in a second direction.

[0017] According to the above configuration, the provision of the rectifying plate can prevent gas from the first power storage stack and the second power storage stack from blowing directly onto the electric device. [Effects of the Invention]

[0018] According to the present disclosure, it is possible to provide an electricity storage device that can exhaust gas discharged from an electricity storage stack to the outside of the accommodating case while suppressing a decrease in the rigidity of the accommodating case. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a schematic diagram showing a vehicle according to a first embodiment. [Figure 2] 2 is a diagram showing a state in which the electricity storage device according to the first embodiment is fixed to a vehicle body. FIG. [Figure 3] 1 is a schematic exploded perspective view of an electricity storage device according to a first embodiment. [Figure 4] 1 is a schematic plan view showing the internal configuration of an electricity storage device according to a first embodiment. [Figure 5] FIG. 5 is a schematic cross-sectional view taken along line VV shown in FIG. [Figure 6] FIG. 10 is a schematic plan view showing the internal configuration of a power storage device according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the embodiments described below, the same or common parts are denoted by the same reference numerals in the drawings, and the description thereof will not be repeated.

[0021] (Embodiment 1) Fig. 1 is a schematic diagram showing a vehicle according to embodiment 1. Fig. 2 is a diagram showing a state in which an electricity storage device according to embodiment 1 is fixed to a vehicle body. Vehicle 1 according to embodiment 1 will be described with reference to Figs. 1 and 2.

[0022] The vehicle 1 is a hybrid vehicle that can run using at least one of the power of a motor and an engine, or an electric vehicle that runs using driving force obtained from electrical energy.

[0023] The vehicle 1 includes a vehicle body 2, front wheels 3, rear wheels 4, and a power storage device 10. The vehicle body 2 includes a frame member 5. The power storage device 10 is disposed below the vehicle body 2. The power storage device 10 is disposed, for example, between the front wheels 3 and the rear wheels 4. Note that a portion of the power storage device 10 may be disposed overlapping at least one of the front wheels 3 and the rear wheels 4 when viewed from the width direction of the vehicle 1. The power storage device 10 has an upper surface 10a. The upper surface 10a may function as a floor member that defines the interior of the vehicle cabin.

[0024] The framework 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 ends of the vehicle 1 in the width direction. The pair of side members 6 are arranged at a distance inside the pair of side sills 7. The pair of side members 6 and the pair of side sills 7 extend along the front-rear direction of the vehicle 1.

[0025] The pair of side members 6 are spaced apart in the width direction of the vehicle 1. A main body 35 of the electricity storage device 10 is disposed in the gap between the pair of side members 6. A gap is provided between the main body 35 and the pair of side members 6. This makes it possible to suppress input of an impact to the electricity storage device 10 even in the event of a side collision of the vehicle 1.

[0026] Fixed portions 36 are provided on both side surfaces of the main body portion 35 in the width direction of the vehicle 1. The fixed portions 36 are fixed to the pair of side members 6 by fastening members 8.

[0027] The framework member 5 also includes a cross framework member 9. The cross framework member 9 is provided above the electricity storage device 10 so as to straddle from one side sill 7 to the other side sill 7. To the cross framework member 9, an upper surface 10a of the electricity storage device 10 is fixed.

[0028] In the above description, the framework member 5 includes a pair of side members 6 and a pair of side sills 7, but is not limited to this. The pair of side sills 7 may also function as the pair of side members 6. In this case, the pair of side members 6 can be omitted, and the above-mentioned fixed portion 36 may be fixed to the pair of side sills 7.

[0029] Fig. 3 is a schematic exploded perspective view of the energy storage device according to embodiment 1. Fig. 4 is a schematic plan view showing the internal configuration of the energy storage device according to embodiment 1. Fig. 5 is a schematic cross-sectional view taken along line IV-IV shown in Fig. 4. Details of the energy storage device 10 will be described with reference to Figs. 3 to 5.

[0030] As shown in FIGS. 3 and 4, the power storage device 10 includes a power storage module 20, a housing case 30, case-side exhaust valves 41 and 42, and an electric device 70.

[0031] The power storage module 20 includes a first power storage stack 21 and a second power storage stack 22. The first power storage stack 21 and the second power storage stack 22 are arranged side by side at a distance in a first direction. Note that the first direction is, for example, parallel to the front-to-rear direction of the vehicle 1 when the power storage device 10 is mounted on the vehicle 1. A gap G is formed between the first power storage stack 21 and the second power storage stack 22.

[0032] The first power storage stack 21 is located on one side in the first direction, and the second power storage stack 22 is located on the other side in the first direction. The first power storage stack 21 and the second power storage stack 22 are electrically connected in series.

[0033] The first power storage stack 21 includes a plurality of first unit cells 210. The plurality of first unit cells 210 are electrically connected in series. The plurality of first unit cells 210 are arranged in a second direction (DR2 direction) perpendicular to the first direction. Note that the second direction is, for example, parallel to the left-right direction of the vehicle 1 in the mounted state.

[0034] The first unit cell 210 has an elongated shape with the longitudinal direction being the first direction, and a flat rectangular parallelepiped shape with a thickness in the second direction.

[0035] The first unit cell 210 includes a housing 211. The housing 211 has a first end face 211a and a second end face 211b arranged in a first direction. The first end face 211a faces the side opposite to the side on which the second power storage stack 22 is located in the first direction. The second end face 211b faces the second power storage stack 22. A first exhaust valve 215 is provided on the second end face 211b.

[0036] The multiple first unit cells 210 are arranged so that each first exhaust valve 215 faces the second power storage stack 22. The first exhaust valve 215 opens when the internal pressure of the housing 211 exceeds a predetermined value, and exhausts gas inside the housing 211 to the outside of the housing 211. Specifically, the first exhaust valve 215 exhausts gas toward the second power storage stack 22 side.

[0037] The second power storage stack 22 includes a plurality of second unit cells 220. The plurality of second unit cells 220 are electrically connected in series. The plurality of second unit cells 220 are arranged in a second direction.

[0038] The second unit cell 220 has a longitudinal shape with the first direction as its longitudinal direction, and a flat rectangular parallelepiped shape with a thickness in the second direction.

[0039] The second unit cell 220 includes a housing 221. The housing 221 has a first end face 221a and a second end face 221b arranged in a first direction. The first end face 221a faces the first power storage stack 21. The second end face 221b faces the opposite side in the first direction to the side on which the first power storage stack 21 is located. A second exhaust valve 225 is provided on the first end face 221a.

[0040] The multiple second unit cells 220 are arranged so that each second exhaust valve 225 faces the first power storage stack 21. The second exhaust valve 225 opens when the internal pressure of the housing 221 exceeds a predetermined value, and exhausts gas inside the housing 221 to the outside of the housing 221. Specifically, the second exhaust valve 225 exhausts gas toward the first power storage stack 21 side.

[0041] A single or multiple electrode bodies 25 are housed inside the casings 211, 221. When a single electrode body 25 is housed inside the casings 211, 221, the electrode body 25 has a shape that extends in the longitudinal direction. The electrode body 25 may be a laminated electrode body in which a negative electrode sheet, a separator, and a positive electrode sheet are laminated, or may be a wound electrode body in which a negative electrode sheet, a separator, and a positive electrode sheet are wound.

[0042] When multiple electrode bodies 25 are housed in the housings 211, 221, the multiple electrode bodies 25 are arranged side by side in the longitudinal direction and connected in series. In this case, too, the electrode body 25 may be a laminated electrode body or a wound electrode body.

[0043] The first unit cell 210 and the second unit cell 220 are secondary batteries such as nickel-metal hydride batteries or lithium-ion batteries. The first unit cell 210 and the second unit cell 220 may use a liquid electrolyte or a solid electrolyte. The first unit cell 210 and the second unit cell 220 may be chargeable and dischargeable capacitors.

[0044] The housing case 30 includes an upper member 31 and a lower member 32 serving as a lower case. The lower member 32 has a generally box-like shape that opens upward. The lower member 32 includes a main body portion 35 and a fixed portion 36.

[0045] The main body 35 has a bottom wall 321, a first wall 322, a second wall 323, and a pair of side walls 324 and 325. The first wall 322, the second wall 323, and the pair of side walls 324 and 325 are provided to stand upright from the periphery of the bottom wall 321. The first wall 322, the second wall 323, and the pair of side walls 324 and 325 form a peripheral wall. The peripheral wall is connected to the periphery of the bottom wall 321.

[0046] The first wall portion 322 and the second wall portion 323 face each other in the first direction. The first wall portion 322 is located on one side in the first direction. The second wall portion 323 is located on the other side in the first direction. The pair of side walls 324, 325 face each other in the second direction. The pair of side walls 324, 325 connect the first wall portion 322 and the second wall portion 323. The side wall portion 324 connects the ends of the first wall portion 322 and the second wall portion 323 that are located on one side in the second direction. The side wall portion 325 connects the ends of the first wall portion 322 and the second wall portion 323 that are located on the other side in the second direction.

[0047] The fixed portion 36 is provided on the outer surfaces of the pair of side wall portions 324, 325. The fixed portion 36 is provided so as to extend discontinuously in the first direction. The portion of the fixed portion 36 located furthest to one side in the first direction is longer in the first direction than the other portions.

[0048] The upper member 31 has a generally plate-like shape. The upper member 31 closes the opening of the lower case 200. The shape of the upper member is not limited to a plate-like shape, and may be a generally box-like shape that opens downward.

[0049] The electric device 70 is disposed in the gap between the first power storage stack 21 and the second power storage stack 22. The electric device 70 includes, for example, a battery ECU (Electronic Control Unit) 71 and a junction box 72. The battery ECU 71 is disposed in the center of the gap in the second direction. The junction box 72 is disposed alongside the battery ECU 71 in the second direction. The junction box 72 is disposed on one side of the battery ECU 71 in the second direction.

[0050] 5, the electric device 70 is disposed at a position that does not overlap with the plurality of first exhaust valves 215 and the plurality of second exhaust valves 225 in the first direction. This makes it possible to prevent gas discharged from the first power storage stack 21 and / or the second power storage stack 22 from directly blowing onto the electric device 70. The plurality of first exhaust valves 215 and the plurality of second exhaust valves 225 are disposed, for example, above the electric device 70.

[0051] 3 and 4 , the peripheral wall of the housing case 30 is provided with case-side exhaust valves 41, 42 that can exhaust gas discharged into the housing case 30 from the first power storage stack 21 and / or the second power storage stack 22. The case-side exhaust valve 41 is provided on the side wall 324. The case-side exhaust valve 42 is provided on the side wall 325.

[0052] The case-side exhaust valves 41 and 42 function as pressure relief valves, and discharge the gas inside the accommodating case 30 to the outside of the accommodating case 30 when the pressure inside the accommodating case 30 exceeds a predetermined pressure.

[0053] A space S is provided in the gap G between the first electricity storage stack 21 and the second electricity storage stack 22, through which gas discharged from at least one of the plurality of first unit cells 210 included in the first electricity storage stack 21 or gas discharged from at least one of the plurality of second unit cells 220 included in the second electricity storage stack 22 can flow. The gas discharged into the space S is discharged to the outside of the housing case 30 through the case-side exhaust valves 41, 42.

[0054] As described above, in the present embodiment, gas can be discharged to the outside from the case-side exhaust valves 41, 42 through the gap G between the first power storage stack 21 and the second power storage stack 22 in which the electric device 70 is arranged. Therefore, compared to a configuration in which an exhaust path for discharging gas is provided inside the accommodating case and a large number of holes are provided in the accommodating case to introduce gas from the plurality of power storage cells included in each power storage stack into the exhaust path, the power storage device 10 according to the present embodiment can maintain good rigidity of the accommodating case 30. In addition, since the processing for providing a large number of holes in the accommodating case is not required, manufacturing costs can be reduced.

[0055] Furthermore, the case-side exhaust valves 41, 42 are provided in portions of the peripheral wall portions that face the gap between the first power storage stack 21 and the second power storage stack 22. That is, the case-side exhaust valves 41, 42 are provided in approximately the center of the pair of side wall portions 324, 325 in the first direction. This allows gas discharged into the space S provided in the gap G between the first power storage stack 21 and the second power storage stack 22 to be discharged to the outside of the accommodation case 30 in the shortest possible time. As a result, heating of the first power storage stack 21 and the second power storage stack 22 by the discharged gas can be suppressed.

[0056] Furthermore, each of the plurality of first unit cells 210 is provided with a first exhaust valve 215 capable of discharging gas toward the second power storage stack 22 side, and each of the plurality of second unit cells 220 is provided with a second exhaust valve 225 capable of discharging gas toward the first power storage stack 21 side. Therefore, gas from the first power storage stack 21 and / or the second power storage stack 22 can be directly discharged into the space S.

[0057] Gas tends to accumulate on both sides in the second direction in the gap G. In the present embodiment, the battery ECU 71 is disposed in the center of the gap G in the second direction, thereby preventing the battery ECU 71 from being heated by the accumulated gas.

[0058] (Embodiment 2) 6 is a schematic plan view showing the internal configuration of the power storage device according to Embodiment 2. With reference to FIG. 6, a power storage device 10A according to Embodiment 2 will be described.

[0059] 6, power storage device 10A according to embodiment 2 differs from power storage device 10 according to embodiment 1 in that it includes a current plate 80. The other configurations are substantially the same.

[0060] The rectifying plate 80 guides the gas from the first power storage stack 21 or the gas from the second power storage stack 22 toward both outer sides of the electric device 70 in the second direction in the gap G between the first power storage stack 21 and the second power storage stack 22. In other words, the rectifying plate 80 guides the gas toward portions of the space S that are located on both outer sides of the electric device 70 in the second direction.

[0061] The rectifying plate 80 includes a first rectifying plate 81 and a second rectifying plate 82. The first rectifying plate 81 is disposed between the first power storage stack 21 and the electric device 70. The second rectifying plate 82 is disposed between the second power storage stack 22 and the electric device 70. In the second direction, the widths of the first rectifying plate 81 and the second rectifying plate 82 are greater than the width of the electric device 70. That is, the first rectifying plate 81 is disposed so as to cover the electric device 70 from one side in the first direction. The second rectifying plate 82 is disposed so as to cover the electric device 70 from the other side in the first direction.

[0062] Both ends of the first current rectifying plate 81 in the second direction are inclined toward the second current rectifying plate 82. Both ends of the second current rectifying plate 82 in the second direction are inclined toward the first current rectifying plate 81.

[0063] Even when configured as described above, the power storage device 10A according to embodiment 2 can achieve substantially the same effects as the power storage device 10 according to embodiment 1. In addition, by providing the rectifying plate 80, it is possible to prevent the gas from the first power storage stack 21 or the gas from the second power storage stack 22 from blowing directly onto the electric device 70.

[0064] In the above-described first and second embodiments, the first direction is parallel to the front-rear direction of the vehicle 1 and the second direction is parallel to the left-right direction of the vehicle 1 in the mounted state, but the present invention is not limited to this. The first direction may be parallel to the left-right direction of the vehicle 1 and the second direction may be parallel to the front-rear direction of the vehicle 1.

[0065] Furthermore, in the above-described first and second embodiments, the case where the case-side exhaust valves 41, 42 are provided in a portion of the peripheral wall of the storage case 30 that faces the gap G between the first power storage stack 21 and the second power storage stack 22 has been described as an example, but the present invention is not limited to this. The case-side exhaust valves 41, 42 may be provided in the first wall 322 or the second wall 323. In this case, an exhaust path for exhausting gas is provided inside the peripheral wall of the storage case 30, and an inlet hole for introducing gas into the exhaust path is provided in a portion of the peripheral wall that faces the gap. In the above configuration, the area where the inlet hole is provided is limited, thereby preventing a decrease in the rigidity of the storage case 30.

[0066] The embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0067] REFERENCE SIGNS LIST 1 vehicle, 2 vehicle body, 3 front wheel, 4 rear wheel, 5 frame member, 6 side member, 7 side sill, 8 fastening member, 9 cross frame member, 10, 10A energy storage device, 10a upper surface, 20 energy storage module, 21 first energy storage stack, 22 second energy storage stack, 25 electrode body, 30 housing case, 31 upper member, 32 lower member, 35 main body portion, 36 fixed portion, 41, 42 case-side exhaust valve, 70 electrical equipment, 71 battery ECU, 72 junction box, 80 rectifier plate, 81 first rectifier plate, 82 second rectifier plate, 200 lower case, 210 first unit cell, 211 housing, 211a first end surface, 211b second end surface, 215 first exhaust valve, 220 second unit cell, 221 housing, 221a First end surface, 221b second end surface, 225 second exhaust valve, 321 bottom wall portion, 322 first wall portion, 323 second wall portion, 324, 325 side wall portion, G gap, S space portion.

Claims

1. a first power storage stack and a second power storage stack; an electric device for controlling the first power storage stack and the second power storage stack; a housing case that houses the first power storage stack, the second power storage stack, and the electrical device, the housing case is provided with a case-side exhaust valve capable of exhausting gas discharged into the housing case, the first power storage stack and the second power storage stack are arranged side by side at an interval in a first direction, the electrical device is disposed in a gap between the first power storage stack and the second power storage stack, A storage device, wherein the gap between the first storage stack and the second storage stack is provided with a space portion through which the gas discharged from the first storage stack or the gas discharged from the second storage stack can flow.

2. the housing case has a bottom wall portion and a peripheral wall portion connected to the bottom wall portion, The power storage device according to claim 1 , wherein the case-side exhaust valve is provided in a portion of the peripheral wall that faces the gap between the first power storage stack and the second power storage stack.

3. the first storage stack includes a plurality of first unit cells arranged in a second direction perpendicular to the first direction, the second storage stack includes a plurality of second unit cells arranged in the second direction, each of the plurality of first unit cells is provided with a first exhaust valve capable of discharging the gas toward the second power storage stack; The power storage device according to claim 1 , wherein each of the second unit cells is provided with a second exhaust valve capable of discharging the gas toward the first power storage stack.

4. The power storage device according to claim 3 , wherein the electrical device is disposed at a position not overlapping with the plurality of first exhaust valves and the plurality of second exhaust valves in the first direction.

5. the electrical equipment includes a battery ECU and a junction box; the battery ECU is disposed in a center portion of the gap in a second direction perpendicular to the first direction, The power storage device according to claim 1 , wherein the junction box is arranged to be aligned with the battery ECU in the second direction.

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