Power storage device

Abstract

To provide a power storage device capable of suppressing expansion of a power storage cell to an upper side while suppressing transmission of heat to the upper side of the power storage cell due to gas discharged from the power storage cell.SOLUTION: The power storage device includes a power storage stack including a plurality of power storage cells 100 each having a lower surface 121 and an upper surface 123 and having a safety valve SV disposed on lower surface 121, a support portion supporting the power storage stack from below, an exhaust path 60 provided below the support portion and configured to communicate with a space S located directly below safety valve SV, a cooler 200 disposed below the power storage stack and configured to cool the power storage stack, and a plate-shaped member disposed above the power storage stack and facing upper surface 123 of each of the plurality of power storage cells 100.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

[0002] For example, JP 2022-525014 A discloses a structure in which a power battery pack (electricity storage device) having a plurality of single batteries (electricity storage cells) installed inside a housing case is fixed to the bottom of an electric vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2022-525014 Summary of the Invention [Problem to be solved by the invention]

[0004] In a power storage device, a power storage stack including multiple power storage cells arranged in a storage case may be cooled from below, and such a power storage device may be fixed to a vehicle with the top wall of the storage case functioning as a floor panel.

[0005] In such a case, if any of the multiple storage cells generates heat and expands, there is a concern that the upper surface of the cell will expand, affecting the interior of the vehicle. Furthermore, if no measures are taken, there is a concern that the gas emitted from the heated storage cell will heat up the interior of the vehicle.

[0006] 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 suppress the expansion of the energy storage cell toward the upper side while suppressing the transfer of heat toward the upper side of the energy storage cell due to gas discharged from the energy storage cell. [Means for solving the problem]

[0007] A storage device according to a first aspect of the present disclosure includes a storage stack including a plurality of storage cells, each having a lower surface and an upper surface and a safety valve disposed on the lower surface; a support portion that supports the storage stack from below; an exhaust path that is disposed below the support portion and is capable of communicating with a space located below the safety valve; a cooler that is disposed below the storage stack and cools the storage stack; and a plate-shaped member that is disposed above the storage stack and faces the upper surface of each of the plurality of storage cells.

[0008] According to the above configuration, by providing a safety valve on the lower surface of the energy storage cell and providing an exhaust path below the support portion that supports the energy storage stack, it is possible to prevent gas discharged from the energy storage cell from moving through the upper side of the energy storage stack. This prevents heat transfer to the upper side of the energy storage cell by the gas discharged from the energy storage cell. Furthermore, the gas discharged from the energy storage cell can be cooled by a cooler disposed below the energy storage device. In addition, the plate-shaped member disposed above the energy storage stack prevents the upper surface of each of the multiple energy storage cells from expanding upward.

[0009] In the energy storage device based on the first aspect of the present disclosure, the plurality of energy storage cells may be arranged in a first direction orthogonal to a vertical direction in which the upper surface and the lower surface are aligned. When a direction orthogonal to the vertical direction and the first direction is defined as a width direction of each of the plurality of energy storage cells, the plate-like member may be configured as a restraint band that is arranged along the first direction above at least a central portion in the width direction of the upper surface of each of the plurality of energy storage cells and restrains the energy storage stack from both sides of the energy storage stack in the first direction.

[0010] According to the above configuration, the restraint band can prevent the upper surface of each of the plurality of energy storage cells from expanding upward.

[0011] The energy storage device according to the first aspect of the present disclosure may further include a first outer restraint band and a second outer restraint band arranged along the first direction above both sides in the width direction of the upper surface of each of the plurality of energy storage cells, and restraining the energy storage stack from both sides of the energy storage stack in the first direction. In this case, the restraint band may be disposed between the first outer restraint band and the second outer restraint band in the width direction.

[0012] According to the above configuration, the restraint band arranged between the first outer restraint band and the second outer restraint band in the width direction can effectively prevent the central portion of the upper surface in the width direction from expanding upward.

[0013] In the power storage device based on the first aspect of the present disclosure, the restraint band may entirely cover the upper surface of each of the plurality of power storage cells in the width direction.

[0014] According to the above configuration, it is possible to generally prevent the upper surfaces of the plurality of power storage cells from expanding upward.

[0015] A storage device according to a first aspect of the present disclosure includes a storage stack including a plurality of storage cells, each having a lower surface and an upper surface and a safety valve disposed on the lower surface; a support portion that supports the storage stack from below; an exhaust path that is disposed below the support portion and is capable of communicating with a space located below the safety valve; a cooler that is disposed below the storage stack and cools the storage stack; an upper member that covers the storage stack from above; and an adhesive disposed between the upper member and the upper surface of each of the plurality of storage cells.

[0016] According to the above configuration, by providing a safety valve on the lower surface of the energy storage cell and providing an exhaust path below the support portion that supports the energy storage stack, it is possible to prevent gas discharged from the energy storage cell from moving through the upper side of the energy storage stack. This prevents heat transfer to the upper side of the energy storage cell by the gas discharged from the energy storage cell. Furthermore, the gas discharged from the energy storage cell can be cooled by a cooler disposed below the energy storage device. In addition, the adhesive disposed between the upper surface of each of the multiple energy storage cells and the upper member prevents the upper surface of each of the multiple energy storage cells from expanding upward. Furthermore, the adhesive can suppress vibration of the upper member.

[0017] The power storage device according to the present disclosure may further include a lower case including a bottom wall portion located below the power storage stack. In this case, the support portion may be formed by a part of the bottom wall portion, and the cooler may be disposed below the bottom wall portion.

[0018] According to the above configuration, the exhaust path is provided below the bottom wall portion that constitutes the support portion, so that when gas is exhausted from the energy storage cells, the gas can be exhausted to the outside (below) of the lower case.

[0019] The power storage device according to the present disclosure may include a lower case including a bottom wall portion located below the power storage stack, and a path defining member disposed between the bottom wall portion and the power storage stack and defining the exhaust path together with the bottom wall portion. The cooler may be disposed between the power storage stack and the path defining member. The support portion may include the path defining member and the cooler.

[0020] According to the above configuration, gas discharged downward from the safety valve of the energy storage cell can flow into the space formed between the bottom wall of the lower case and the path defining member. This prevents the discharged gas from flowing upward. In addition, the cooler disposed on the path defining member can cool the gas flowing in the exhaust path. [Effects of the Invention]

[0021] According to the present disclosure, an object of the present disclosure is to provide an energy storage device that can suppress the expansion of the energy storage cell upward while suppressing the transfer of heat to the upper side of the energy storage cell by gas discharged from the energy storage cell. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a diagram showing a vehicle equipped with an electricity storage device according to a first embodiment. [Figure 2] 2 is a perspective view showing the electricity storage device and a frame member according to the first embodiment. FIG. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III shown in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV shown in FIG. [Figure 5] FIG. 1 is a plan view showing a cooler according to a first embodiment. [Figure 6] FIG. 6 is a cross-sectional view taken along line VI-VI shown in FIG. 5. [Figure 7] FIG. 10 is a cross-sectional view showing an electricity storage device according to a second embodiment. [Figure 8] FIG. 10 is a cross-sectional view showing an electricity storage device according to a third embodiment. [Figure 9] FIG. 10 is a cross-sectional view showing an electricity storage device according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0023] 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.

[0024] (Embodiment 1) Fig. 1 is a diagram showing a vehicle equipped with an electricity storage device according to embodiment 1. Fig. 2 is a perspective view showing an electricity storage device and a frame member according to embodiment 1. Fig. 3 is a cross-sectional view taken along line III-III shown in Fig. 2. Fig. 4 is a cross-sectional view taken along line IV-IV shown in Fig. 3.

[0025] 1, a vehicle 1 includes a vehicle body 2 and a power storage device 10. Examples of the vehicle 1 include a hybrid electric vehicle, a plug-in hybrid electric vehicle, and an electric vehicle (battery electric vehicle).

[0026] 1 and 2, the vehicle body 2 includes a frame member 20. The frame member 20 is disposed at the bottom of the vehicle body 2. The frame member 20 has a pair of first frames 21, a pair of second frames 22, a first cross frame 23, and a second cross frame 24.

[0027] The pair of first frames 21 face each other in a first direction. Each first frame 21 has a shape extending along a second direction that is perpendicular to both the first direction and the up-down direction. For example, the first direction may be a direction parallel to the front-to-rear direction of the vehicle 1, and the second direction may be a direction parallel to the left-to-right direction (width direction) of the vehicle 1.

[0028] The pair of second frames 22 face each other in the second direction. Each second frame 22 has a shape extending along the first direction. An end of each second frame 22 in the first direction is connected to the first frame 21. The pair of second frames 22, together with the pair of first frames 21, are formed in a substantially rectangular tubular shape that surrounds the power storage device 10.

[0029] The first cross frame 23 is disposed between the pair of first frames 21 and connects the pair of second frames 22 to each other.

[0030] The second cross frame 24 is disposed between the pair of first frames 21 and connects the pair of second frames 22. The second cross frame 24 is spaced apart from the first cross frame 23 in the first direction. Each of the first cross frame 23 and the second cross frame 24 constitutes, for example, a seat cross.

[0031] The power storage device 10 is attached to a frame member 20. The upper surface of the power storage device 10, that is, an upper wall portion 322 of an upper member 320 described below, may function as a floor panel.

[0032] As shown in FIG. 2, the power storage device 10 is disposed below the first cross frame 23 and the second cross frame 24.

[0033] 1 to 4, the energy storage device 10 includes four energy storage stacks 11 to 14, a first outer restraint band 53A and a second outer restraint band 53B, an exhaust path 60, an adhesive 80, a cooler 200, a housing case 300, a bracket 319, a panel member 330, a reinforcing member 620, an equipment unit 800, a first thermally conductive adhesive 910, and a second thermally conductive adhesive 920. The number of energy storage stacks is not limited to four.

[0034] Each of the power storage stacks 11 to 14 includes a plurality of power storage cells 100. The plurality of power storage cells 100 are arranged in a first direction. Each of the power storage stacks 11 to 14 is formed in the shape of a rectangular parallelepiped that is long in the first direction. As shown in FIG. 2, the four power storage stacks 11 to 14 are arranged side by side along the second direction.

[0035] 3, a pair of end plates 51 are provided on both sides of the plurality of storage cells 100 in the first direction to sandwich the plurality of storage cells 100 from both sides in the first direction. A monitoring unit (Smart Battery Management) 52 is arranged on the outside of each end plate 51 in the first direction.

[0036] The equipment unit 800 is disposed, for example, at an end in the first direction. In this embodiment, the equipment unit 800 is disposed on the rear part of the upper member 320 in the front-rear direction of the vehicle 1. The equipment unit 800 has a junction box 812, an electricity supply unit 814, an electronic control unit 816, a first cooler 822, a second cooler 824, and an equipment cover 830.

[0037] The junction box 812 is disposed above the upper member 320. The junction box 812 houses a relay, a fuse, etc. The junction box 812 is cooled by a first cooler 822 disposed between the junction box 812 and the upper member 320.

[0038] The power supply unit 814 is disposed above the junction box 812. The power supply unit 814 is cooled by a second cooler 824 disposed above the power supply unit 814. The electronic control unit 816 is disposed above the junction box 812.

[0039] The equipment cover 830 houses the junction box 812 , the power supply unit 814 , the electronic control unit 816 , and the second cooler 824 .

[0040] 3 and 4, reinforcing member 620 is disposed on upper member 320. More specifically, reinforcing member 620 is placed on upper wall portion 322. Reinforcing member 620 has a function of dispersing a load that is locally applied from above to power storage device 10 by an occupant of vehicle 1.

[0041] As shown in FIG. 4, each storage cell 100 has an electrode assembly 110, a cell case 120, and a pair of external terminals .

[0042] The electrode assembly 110 may be formed as a wound body in which a positive electrode sheet and a negative electrode sheet are wound with a separator interposed therebetween, or may be formed as a laminate in which a positive electrode sheet and a negative electrode sheet are stacked with a separator interposed therebetween. The electrode assembly 110 is formed in a shape that is long in the second direction.

[0043] The cell case 120 houses the electrode assembly 110. The cell case 120 is formed in a rectangular parallelepiped shape. The cell case 120 is made of a metal such as aluminum. The cell case 120 includes a bottom surface 121, a pair of side surfaces 122, and a top surface 123.

[0044] The upper surface 123 and the lower surface 121 are aligned in the vertical direction. A safety valve SV is provided on the lower surface 121. The pair of side surfaces 122 are aligned in the above-mentioned second direction (width direction) perpendicular to the vertical direction and the first direction. An external terminal 130 is provided on each of the pair of side surfaces 122. The external terminal provided on one of the pair of side surfaces 122 and the external terminal provided on the other of the pair of side surfaces 122 have opposite polarities.

[0045] The plurality of energy storage cells 100 are restrained in the first direction by a first outer restraint band 53A and a second outer restraint band 53B.

[0046] The first outer restraint band 53A restrains the power storage stack from both sides of the power storage stack in the first direction on one side in the second direction. The first outer restraint band 53A has a first portion 53A1 and a second portion 53A2.

[0047] The first portion 53A1 is located on the upper surface 123 side. The first portion 53A1 is routed along the first direction so as to straddle above one side of the upper surface 123 of each of the plurality of energy storage cells 100 in the second direction (width direction).

[0048] The second portion 53A2 is located on the side of the lower surface 121. The second portion 53A2 is routed along the first direction so as to straddle below one side of the lower surface 121 of each of the plurality of energy storage cells 100 in the second direction.

[0049] The second outer restraint band 53B restrains the power storage stack from both sides of the power storage stack in the first direction on the other side in the second direction. The second outer restraint band 53B has a first portion 53B1 and a second portion 53B2.

[0050] The first portion 53B1 is located on the upper surface 123 side. The first portion 53A1 is routed along the first direction so as to straddle the upper side of the other side in the second direction (width direction) of the upper surfaces 123 of the plurality of energy storage cells 100.

[0051] The second portion 53B2 is located on the side of the lower surface 121. The second portion 53B2 is routed along the first direction so as to straddle below the other side of the lower surface 121 of each of the plurality of energy storage cells 100 in the second direction.

[0052] The storage case 300 accommodates therein four power storage stacks 11 to 14. The storage case 300 includes a lower case 310, an upper member 320, and a cross member 360.

[0053] Upper member 320 covers multiple power storage stacks 11-14 from above. Upper member 320 has an upper wall portion 322. Upper wall portion 322 may have a bead formed thereon extending in the second direction. The peripheral edge of upper member 320 is connected to the peripheral edge of lower case 310 by bolts or the like via a sealing member.

[0054] Lower case 310 has a generally box-like shape that opens upward. Lower case 310 has a bottom wall 311 and a peripheral wall 317. Peripheral wall 317 stands upright from the peripheral edge of bottom wall 311. Peripheral wall 317 has a shape that surrounds the lower parts of power storage stacks 11-14. A bracket 319 is fixed to peripheral wall 317 for attaching a panel member 330 (described later).

[0055] The bottom wall portion 311 supports the plurality of power storage stacks 11 to 14. The bottom wall portion 311 includes a pair of mounting portions 312, a bottom wall portion 313, and a connection portion 314 in each region where the power storage stacks 11 to 14 are arranged.

[0056] The pair of mounting portions 312 constitute support portions that support the power storage stack. The pair of mounting portions 312 are positioned apart in the second direction. The power storage stack is placed on the pair of mounting portions 312. A first thermally conductive adhesive 910 is arranged between the pair of mounting portions 312 and the lower surface of the power storage stack (specifically, the lower surface 121 of each of the multiple power storage cells 100).

[0057] The bottom wall portion 313 is located between the pair of mounting portions 312 in the second direction. The bottom wall portion 313 is located at a position lower in the up-down direction than the pair of mounting portions 312. A through hole 313h is provided in the bottom wall portion 313. The connection portion 314 connects the pair of mounting portions 312 and the bottom wall portion 313.

[0058] A space S is formed between the bottom wall portion 313 and the lower surface of the power storage stack. The space S is surrounded by the lower surface of the power storage stack, the bottom wall portion 313, and the connection portion 314. In the region where each power storage stack is arranged, the safety valve SV provided in each of the multiple power storage cells 100 faces the space S. The space S is located directly below each safety valve SV.

[0059] A waterproof sheet 41, a waterproof sealing member 42, an adhesive 44, and a heat insulating member 43 are arranged in the space S. The waterproof sheet 41 is arranged in a state where it covers the through-hole 313h. The waterproof sheet 41 prevents water from entering the space S through the through-hole 313h. The waterproof sheet 41 may be provided to be gas permeable, or may be configured to rupture when gas is discharged from the safety valve SV, thereby allowing the gas to pass through the through-hole 313h.

[0060] The sealing member 42 is disposed above the waterproof sheet 41 and is fixed to the waterproof sheet 41 with an adhesive 44. When viewed from the top and bottom, the sealing member 42 includes a portion surrounding the through-hole 313h and the safety valve SV. This makes it possible to prevent water from spreading within the space S if water enters the space S through the through-hole 313h. If a waterproof adhesive is used for the sealing member 42, the adhesive 44 may be omitted.

[0061] Furthermore, when the sealing member 42 has a covering portion that covers the portion of the waterproof sheet 41 that is located above the through-hole 313h, the covering portion is configured to break or otherwise deform when gas is discharged from the safety valve SV, thereby allowing the gas to pass through the through-hole 313h.

[0062] The heat insulating member 43 is sandwiched between a portion of the underside of the electricity storage stack that is located around the safety valve SV and the sealing member 42. The heat insulating member 43 does not cover the safety valve SV, and the safety valve SV is exposed from the heat insulating member 43. The heat insulating member 43 is made of, for example, mica, which is a natural inorganic mineral solidified by heat pressing. The heat insulating member 43 may cover the safety valve SV, in which case the heat insulating member 43 is provided with a notch or the like that allows it to be broken by gas discharged from the safety valve SV.

[0063] The cross member 360 is fixed to a portion of the bottom wall portion 311 that is located between a pair of power storage stacks adjacent to each other in the second direction. The cross member 360 extends along the first direction. The cross member 360 may be connected to wall portions of the peripheral wall portion 317 that are located on both sides in the first direction. The cross member 360 may be connected to the pair of first frames 21 via brackets (not shown).

[0064] The adhesive 80 is disposed above each of the power storage stacks 11 to 14. Specifically, the adhesive 80 is disposed between each of the power storage stacks 11 to 14 and the upper member 320. The adhesive 80 has a first filling portion 81 that fills the gap between the upper wall portion 322 and the upper surfaces 123 of the multiple power storage cells 100 exposed from the first outer restraint band 53A and the second outer restraint band 53B. The adhesive 80 may also have a second filling portion 82 that fills the gap between the upper wall portion 322 and a first portion 53A1 of the first outer restraint band 53A and a first portion 53B1 of the second outer restraint band 53B.

[0065] In the above description, the first filling portion 81 entirely covers the upper surfaces 123 of the multiple energy storage cells 100 exposed from the first outer restraint band 53A and the second outer restraint band 53B, but this is not limiting. The first filling portion 81 only needs to cover at least one-third of the width of the upper surfaces 123 in the second direction. It is preferable that the first filling portion 81 covers at least the center of the upper surfaces 123. Furthermore, the first outer restraint band 53A and the second outer restraint band 53B may be omitted.

[0066] The panel member 330 is disposed below the lower case 310. The panel member 330 covers the bottom wall portion 311 of the lower case 310 from below. The panel member 330 also covers the cooler 200 from below, and protects the cooler 200. Specifically, the panel member 330 is fixed to the lower case 310 by fastening members 71, 72, etc. Both end sides of the panel member 330 in the second direction are fixed by fastening members 71 to brackets 319 fixed to the peripheral wall portion 317. A portion of the panel member 330 corresponding to a position between a pair of power storage stacks adjacent to each other in the second direction is fixed by fastening members to a portion of the bottom wall portion 311 positioned between the pair of power storage stacks adjacent to each other in the second direction.

[0067] The panel member 330 has a shape in which the portions of its outer surface located below the power storage stacks 11-14 are downwardly convex, and the portions of its inner surface located below the power storage stacks 11-14 are downwardly concave.

[0068] The panel member 330 forms an exhaust path 60 between the bottom wall portion 311 and each of the power storage stacks 11 to 14 below. The exhaust paths 60 formed below each of the power storage stacks 11 to 14 are independent of one another, but this is not limitative and the exhaust paths 60 may be connected to each other. The exhaust path 60 is provided so as to be able to communicate with the space S facing the safety valve SV via the through hole 313h. The exhaust path 60 is a path for discharging gas discharged from the safety valve SV to the outside of the power storage device 10.

[0069] A protective plate 350 is disposed on the inner surface of the panel member 330. The protective plate 350 is disposed below the safety valve SV. The protective plate 350 receives the blast discharged from the safety valve SV. The protective plate 350 is made of, for example, mica, which is a natural inorganic mineral solidified by heat pressing.

[0070] Each exhaust path 60 is provided with a collector 335 that collects foreign matter such as debris contained in the gas discharged into the exhaust path 60. A barrier member 61 is disposed between the cooler 200 and the panel member 330 on at least one side of each exhaust path 60 in the second direction. The barrier member 61 prevents the gas discharged into the exhaust path 60 from spreading in the second direction, for example. The barrier member 61 is made of, for example, silicone foam.

[0071] The cooler 200 is disposed below the plurality of power storage stacks 11 to 14. In the present embodiment, the cooler 200 is disposed outside the housing case 300. Specifically, the cooler 200 is disposed below the bottom wall portion 311 of the lower case 310. The cooler 200 is disposed between the bottom wall portion 311 and the panel member 330. In other words, the cooler 200 is disposed inside the exhaust path 60.

[0072] A second thermally conductive adhesive 920 is disposed between the cooler 200 and the bottom wall portion 311 (more specifically, the pair of mounting portions 312). The cooler 200 cools the multiple power storage stacks 11 to 14. A cooling medium such as oil flows within the cooler 200.

[0073] Fig. 5 is a plan view schematically showing the cooler. Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 5. As shown in Figs. 5 and 6, the cooler 200 has four cooling sections 210, a folded section 220, and a connecting section 230.

[0074] Each cooling section 210 has a shape that extends elongatedly in the first direction. Each cooling section 210 cools one power storage stack. Note that in FIG. 5, each power storage stack 11 to 14 is indicated by a two-dot chain line. As shown in FIG. 4, each cooling section 210 is in contact with the lower surface 121 of each power storage stack 11 to 14 via a second thermally conductive adhesive 920, a pair of mounting sections 312, and a first thermally conductive adhesive 910. The second thermally conductive adhesive 920 and the first thermally conductive adhesive 910 extend along the first direction. Each cooling section 210 may be formed by extrusion molding of a metal such as aluminum. As shown in FIGS. 4 and 5, each cooling section 210 has an upstream flow path 211 and a downstream flow path 212.

[0075] The upstream flow path 211 is provided on the upstream side in the flow direction of the cooling medium. The downstream flow path 212 is provided on the downstream side in the flow direction of the cooling medium. As shown in FIG. 5 , the upstream flow path 211 and the downstream flow path 212 have a shape that extends along a first direction. The upstream flow path 211 and the downstream flow path 212 are adjacent to each other in a second direction. The cooling medium flows through the upstream flow path 211 from one side to the other side in the first direction, and flows through the downstream flow path 212 from the other side to one side in the first direction.

[0076] The turning portion 220 connects the downstream end of the upstream flow passage 211 and the upstream end of the downstream flow passage 212. Therefore, as shown by the arrows in Fig. 5, the cooling medium flows through the upstream flow passage 211, the turning portion 220, and the downstream flow passage 212 in this order.

[0077] The connecting portion 230 connects the four cooling portions 210 to one another. As shown in FIG.

[0078] The connecting portion main body 232 connects the four cooling portions 210 to one another. Therefore, the cooling media that have flowed through each downstream flow path 212 join together inside the connecting portion main body 232. The connecting portion main body 232 may be formed in a substantially rectangular parallelepiped shape.

[0079] The partition wall 234 divides the interior of the connecting portion main body 232 into two spaces. In this embodiment, as shown in FIG. 6, the partition wall 234 divides the interior of the connecting portion main body 232 into upper and lower halves. The upstream ends of the upstream flow paths 211 are connected to the space above the partition wall 234 in the connecting portion main body 232 (hereinafter referred to as the "upstream space S11"), and the downstream ends of the downstream flow paths 212 are connected to the space below the partition wall 234 in the connecting portion main body 232 (hereinafter referred to as the "downstream space S12"). Therefore, the cooling medium that flows into the upstream space S11 flows into each upstream flow path 211. The cooling medium that flows out of each downstream flow path 212 flows into the downstream space S12.

[0080] As shown in FIGS. 5 and 6, an inlet portion 236 and an outlet portion 238 are connected to the connecting portion 230.

[0081] The inlet portion 236 communicates between the upstream space S11 inside the connecting portion main body 232 and the outside of the connecting portion main body 232. Therefore, the cooling medium flows from the outside of the connecting portion main body 232 into the upstream space S11 inside the connecting portion main body 232 through the inlet portion 236. In this embodiment, the inlet portion 236 is connected to the upper surface of the connecting portion main body 232.

[0082] The outflow portion 238 communicates between the downstream space S12 in the connecting portion main body 232 and the outside of the connecting portion main body 232. Therefore, the cooling medium flows out from the downstream space S12 of the connecting portion main body 232 to the outside of the connecting portion main body 232 through the outflow portion 238. In this embodiment, the outflow portion 238 is connected to the upper part of the connecting portion main body 232 and the partition wall 234. Note that the cooling medium flowing out of the connecting portion main body 232 through the outflow portion 238 has a higher temperature than the cooling medium flowing into the connecting portion main body 232 through the inflow portion 236.

[0083] 3 and 4 again, when gas is discharged downward from the safety valve SV due to heat generation or the like in any of the energy storage cells 100, the gas passes through the through-holes 310h and is introduced into the exhaust path 60 located below the pair of mounting portions 312 that support the energy storage stack. The gas introduced into the exhaust path 60 is discharged to the outside from the end side of the exhaust path 60 in the first direction.

[0084] In this way, by providing the safety valve SV on the lower surface 121 of the energy storage cell 100 and providing the exhaust path 60 below the support portion that supports the energy storage stack, it is possible to prevent the gas discharged from the energy storage cell 100 from moving through the upper side of the energy storage stack. This makes it possible to prevent the gas discharged from the energy storage cell 100 from transferring heat to the upper side of the energy storage cell 100. As a result, it is possible to prevent heat from being transferred into the vehicle compartment located above the energy storage device 10. In particular, when the upper wall portion 322 of the energy storage device 10 functions as a floor panel, the above-mentioned effect can be preferably exerted.

[0085] Furthermore, in the present embodiment, the cooler 200 is disposed in the exhaust gas path 60, thereby making it possible to cool the gas discharged from the energy storage cells 100. This also makes it possible to prevent the heat from the gas from being transferred to the vehicle interior located above the energy storage device 10.

[0086] Furthermore, when gas is discharged from the energy storage cells 100, the temperature of the energy storage cells 100 increases, causing the cells to expand. However, as described above, the adhesive 80 disposed above the energy storage stack can prevent the upper surfaces 123 of the multiple energy storage cells 100 from expanding upward. This can prevent the upper wall portion 322 from being deformed by the load caused by the expansion. In particular, when the upper wall portion 322 of the energy storage device 10 functions as a floor panel, it can directly prevent the interior of the vehicle from being deformed by the expansion. The adhesive 80 can also suppress vibration of the upper member 320.

[0087] (Embodiment 2) 7 is a cross-sectional view showing an electricity storage device according to embodiment 2. Note that Fig. 7 shows a cross-sectional view at a position corresponding to Fig. 3.

[0088] 7, energy storage device 10A according to embodiment 2 differs from energy storage device 10 according to embodiment 1 in that a plate-like member 90A is used instead of adhesive 80. The other configurations are substantially the same.

[0089] Each of the plurality of plate-like members 90A is disposed above a corresponding one of the power storage stacks 11 to 14, and faces an upper surface 123 of each of the plurality of power storage cells 100 included in the corresponding power storage stack. The plate-like member 90A is arranged along the first direction above at least a central portion in the second direction of the upper surface 123 of each of the plurality of power storage cells 100, and is composed of restraint bands 53 that restrain the power storage stack from both sides of the power storage stack in the first direction. The restraint bands 53 entirely cover, in the second direction, the upper surface 123 of each of the plurality of power storage cells 100 included in the corresponding one of the power storage stacks 11 to 14.

[0090] Even in the case of the above-described configuration, the restraint bands 53 can prevent the upper surfaces 123 of the plurality of energy storage cells 100 from expanding upward. Therefore, the energy storage device 10A according to the second embodiment can achieve substantially the same effects as the energy storage device 10 according to the first embodiment.

[0091] In addition, in embodiment 2, compared to embodiment 1, the adhesive 80 is omitted, and the first portion 53A1 of the first outer restraint band 53A and the first portion 53B1 of the second outer restraint band 53B described above can be integrated into a single restraint band 53, thereby reducing the number of parts and lowering manufacturing costs.

[0092] (Embodiment 3) 8 is a cross-sectional view showing an electricity storage device according to embodiment 3. Note that Fig. 8 shows a cross-sectional view at a position corresponding to Fig. 3.

[0093] 8, energy storage device 10B according to embodiment 3 differs from energy storage device 10 according to embodiment 1 in that a plate-like member 90B is used instead of adhesive 80. The other configurations are substantially the same.

[0094] Each of the plurality of plate-like members 90B is disposed above a corresponding one of the energy storage stacks 11 to 14, and faces an upper surface 123 of each of the plurality of energy storage cells 100 included in each energy storage stack. The plate-like members 90B are configured with restraint bands 53C. The restraint bands 53C are arranged along the first direction above a central portion in the second direction of the upper surface 123 of each of the plurality of energy storage cells 100, and restrain the energy storage stack from both sides in the first direction.

[0095] The restraint band 53C is located between the first portion 53A1 of the first outer restraint band 53A and the first portion 53B1 of the second outer restraint band 53B in the second direction. The restraint band 53C is spaced apart from the first portion 53A1 and the first portion 53B1 in the second direction. On the upper surface 123, the restraint band 53C only needs to cover at least one-third of the width of the upper surface 123 in the second direction. It is preferable that the restraint band 53C cover at least the center of the upper surface 123.

[0096] Even in the case of the above-described configuration, restraint bands 53C can prevent upward expansion of upper surfaces 123 of the plurality of energy storage cells 100. Therefore, energy storage device 10B according to the third embodiment can achieve substantially the same effects as energy storage device 10 according to the first embodiment.

[0097] (Fourth embodiment) 9 is a cross-sectional view showing an electricity storage device according to embodiment 4. Note that FIG. 9 shows a cross-sectional view at a position corresponding to FIG.

[0098] 9, power storage device 10D according to embodiment 3 differs from power storage device 10 according to embodiment 1 mainly in the shape of lower case 310, the inclusion of path forming member 340, the arrangement of cooler 200, the shape of panel member 330, and the use of both plate-shaped member 90A and adhesive 80D. The other configurations are substantially the same.

[0099] In power storage device 10D according to the third embodiment, bottom wall 311 of lower case 310 has a generally flat plate shape. Bottom wall 311 is disposed below and spaced apart from power storage stacks 11-14. Cooler 200 is housed within lower case 310.

[0100] The plurality of power storage stacks 11-14 are not directly supported by the bottom wall portion 311 of the lower case 310, but are supported by the path forming member 340 and the cooler 200. More specifically, the plurality of power storage stacks 11-14 are supported by a support wall 342 and the cooler 200, which will be described later, and the support wall 342 and the cooler 200 function as supports that support the plurality of power storage stacks 11-14.

[0101] The path forming member 340 is disposed between each of the plurality of power storage stacks 11-14 and the bottom wall portion 311. The path forming member 340 forms an exhaust path 60 together with the bottom wall portion 311. The exhaust path 60 is formed below each of the power storage stacks 11-14. In the present embodiment, a case is exemplified in which the path forming member 340 is configured as a separate member from the lower case 310, but the path forming member 340 may be formed integrally with the lower case 310.

[0102] A through-hole 343h is provided in the path forming member 340. The through-hole 343h is provided below the safety valve SV. The through-hole 343h is located between the path forming member 340 and the lower surface of the electricity storage stack, and connects the space S located below the safety valve to the exhaust path 60.

[0103] The path forming member 340 has a base portion 341 , a support wall 342 , and a connecting portion 343 .

[0104] The base portion 341 is connected to the bottom wall portion 311 of the lower case 310 by welding or the like. The base portion 341 is formed flat.

[0105] The support wall 342 protrudes from the base 341. The support wall 342 supports the cooler 200. That is, the cooler 200 is disposed between the lower surface 121 of the cell casing 120 and the path forming member 340. The cooler 200 is disposed directly below the lower surface 121 with a first thermally conductive adhesive 910 interposed therebetween. The support wall 342 has a first wall portion 342a and a second wall portion 342b.

[0106] The first wall portion 342a supports the upstream flow path 211. More specifically, the first wall portion 342a supports the upstream flow path 211 via the second thermally conductive adhesive 920. The first wall portion 342a is formed in a flat plate shape.

[0107] The second wall portion 342b supports the downstream flow path 212. More specifically, the second wall portion 342b supports the downstream flow path 212 via a second thermally conductive adhesive 920. The second wall portion 342b is formed in a flat plate shape.

[0108] The connecting portion 343 connects the first wall portion 342a and the second wall portion 342b. The connecting portion 343 may be configured as a recess (hereinafter referred to as "recess 343") recessed downward from the support wall 342. The recess 343 forms a single space extending in the first direction (the arrangement direction of the plurality of energy storage cells 100) between the recess 343 and the plurality of energy storage cells 100. Note that the connecting portion 343 may be configured as a protrusion protruding upward from the support wall 342. The recess 343 includes a receiving portion 344 and a connecting portion 345.

[0109] The receiving portion 344 is disposed opposite the SV of the safety valve, and receives the blast discharged from the safety valve SV. The receiving portion 344 is disposed between the safety valve SV and the bottom wall portion 311 of the lower case 310. The receiving portion 344 has a shape that extends in the first direction. The receiving portion 344 is formed in a flat plate shape.

[0110] The receiving portion 344 is spaced upward from the bottom wall portion 311. An elastic member 370 may be disposed between the receiving portion 344 and the bottom wall portion 311. The elastic member 370 has a buffering function that suppresses relative displacement (vibration) of the support wall 342 and the recessed portion 343 with respect to the bottom wall portion 311 due to vibration or the like.

[0111] The connecting portion 345 connects the edge of the receiving portion 344 in the second direction (the direction perpendicular to both the arrangement direction and the up-down direction) to the support wall 342. Each through hole 343h is provided in the connecting portion 345.

[0112] The panel member 330 is provided below the lower case 310. The panel member 330 is joined to the lower surface of the bottom wall portion 311. The panel member 330 has a function of protecting the lower case 310. The panel member 330 may be formed in a flat plate shape.

[0113] The heat insulating member 43 is attached to the lower surface 121 of the cell casing 120 in a state where it covers the safety valve SV. The heat insulating member 43 is provided so as to be breakable by the gas discharged from the safety valve SV.

[0114] Plate-shaped member 90A is configured by the above-mentioned restraint band 53. Adhesive 80D is filled between restraint band 53 and upper wall portion 322.

[0115] In energy storage device 10D according to embodiment 4, when gas is discharged downward from safety valve SV due to a short circuit or the like in any of energy storage cells 100, the gas destroys heat insulating plate 250 and passes through space S located between safety valve SV and receiving portion 344 and through hole 343h, and is introduced into exhaust path 60. The gas introduced into exhaust path 60 is discharged to the outside from the end side of exhaust path 60 in the first direction.

[0116] In this way, by providing the safety valve SV on the lower surface 121 of the energy storage cell 100 and providing the exhaust path 60 below the support portion that supports the energy storage stack, it is possible to prevent the gas discharged from the energy storage cell 100 from moving through the upper side of the energy storage stack. This makes it possible to prevent the gas discharged from the energy storage cell 100 from transferring heat to the upper side of the energy storage cell 100. As a result, it is possible to prevent heat from being transferred into the vehicle compartment located above the energy storage device 10. In particular, when the upper wall portion 322 of the energy storage device 10 functions as a floor panel, the above-mentioned effect can be preferably exerted.

[0117] Furthermore, since the lower surface 121 of the energy storage cell 100 provided with the safety valve SV is cooled by the cooler 200, damage to the lower surface 121 when gas flows out from the safety valve SV can be suppressed.

[0118] Furthermore, as described above, the provision of plate-like member 90A and adhesive 80D can prevent upper surface 123 of each of the plurality of energy storage cells 100 from expanding upward. This can prevent upper wall portion 322 from being deformed by a load caused by the expansion. In particular, when upper wall portion 322 of energy storage device 10 functions as a floor panel, deformation of the interior of the vehicle due to expansion can be directly prevented.

[0119] In addition, by disposing adhesive 80D between plate-like member 90A and upper member 320, vibration of upper member 320 can be suppressed.

[0120] (Other variations) In the above description, the pair of external terminals 130 are provided on the pair of side surfaces 122 of the cell casing 120, but this is not limiting. The pair of external terminals 130 may be provided on the upper surface 123 or the lower surface 121 of the cell casing 120. When the pair of external terminals 130 are provided on the pair of side surfaces 122, the pair of external terminals 130 can be prevented from protruding in the vertical direction from the cell casing 120, thereby making it possible to reduce the height of the energy storage device. Furthermore, when the pair of external terminals 130 are provided on the pair of side surfaces 122 or the upper surface 123, the pair of external terminals 130 are positioned away from the exhaust path 60, thereby suppressing the impact of gas discharged from the safety valve on the pair of external terminals 130.

[0121] Furthermore, it is intended from the beginning that the characteristic portions of the above-described respective embodiments may be combined as appropriate. For example, in power storage device 10D according to embodiment 4, plate member 90A and adhesive 80D may be replaced with adhesive 80 according to embodiment 1, plate member 90A according to embodiment 2, or plate member 90B according to embodiment 3.

[0122] Although the plate-shaped member is configured by a restraining band in the above description, the present invention is not limited to this. The plate-shaped member does not have the function of restraining the plurality of power storage stacks in the first direction, and may be a flat plate fixed inside the housing case 300.

[0123] 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]

[0124] REFERENCE SIGNS LIST 1 vehicle, 2 vehicle body, 10, 10A, 10B, 10D energy storage device, 11, 12, 13, 14 energy storage stack, 20 frame member, 21 first frame, 22 second frame, 23 first cross frame, 24 second cross frame, 41 waterproof sheet, 42 sealing member, 43 heat insulating member, 44 adhesive, 51 end plate, 53, 53C restraining band, 53A first outer restraining band, 53A1 first part, 53A2 second part, 53B second outer restraining band, 53B1 first part, 53B2 second part, 60 exhaust path, 61 barrier member, 71 fastening member, 80, 80D adhesive, 81 first filling part, 82 second filling part, 90, 90A, 90B, 90D expansion suppressing member, 100 energy storage cell, 110 electrode body, 120 Cell case, 121 lower surface, 122 side surface, 123 upper surface, 130 external terminal, 200 cooler, 210 cooling section, 211 upstream flow path, 212 downstream flow path, 220 folded section, 230 connecting section, 232 connecting section main body, 234 partition wall, 236 inlet section, 238 outlet section, 250 heat insulating plate, 300 storage case, 310 lower case, 310h through hole, 311 bottom wall section, 312 placing section, 313 bottom wall section, 313h through hole, 314 connecting section, 317 peripheral wall section, 319 bracket, 320 upper member, 322 upper wall section, 330 panel member, 335 collection section, 340 path forming member, 341 base section, 342 support wall, 342a First wall portion, 342b second wall portion, 343 recess, 343h through hole, 344 receiving portion, 345 connecting portion, 350 protective plate, 360 cross member, 370 elastic member, 620 reinforcing member, 800 equipment unit, 812 junction box, 814 power supply unit, 816 electronic control unit, 822 first cooler, 824 second cooler, 830 equipment cover, 910 first thermally conductive adhesive, 920 second thermally conductive adhesive, S space, S11 upstream space, S12 downstream space, SV safety valve.

Claims

1. an electric storage stack including a plurality of electric storage cells each having a lower surface and an upper surface and a safety valve disposed on the lower surface; a support portion that supports the power storage stack from below; an exhaust path provided below the support portion and capable of communicating with a space located below the safety valve; a cooler disposed below the power storage stack and configured to cool the power storage stack; a plate-shaped member disposed above the power storage stack and facing the upper surface of each of the plurality of power storage cells.

2. the plurality of storage cells are arranged in a first direction perpendicular to a vertical direction in which the upper surface and the lower surface are aligned, In each of the plurality of storage cells, when a direction orthogonal to the up-down direction and the first direction is defined as a width direction, 2. The energy storage device according to claim 1, wherein the plate-shaped member is configured as a restraint band arranged along the first direction above at least a central portion in the width direction of the upper surface of each of the plurality of energy storage cells, and restrains the energy storage stack from both sides of the energy storage stack in the first direction.

3. a first outer restraint band and a second outer restraint band are arranged along the first direction above both sides in the width direction of the upper surface of each of the plurality of energy storage cells, and restrain the energy storage stack from both sides of the energy storage stack in the first direction; The power storage device according to claim 2 , wherein the restraint band is disposed between the first outer restraint band and the second outer restraint band in the width direction.

4. The power storage device according to claim 2 , wherein the restraint band entirely covers the upper surface of each of the plurality of power storage cells in the width direction.

5. an electric storage stack including a plurality of electric storage cells each having a lower surface and an upper surface and a safety valve disposed on the lower surface; a support portion that supports the power storage stack from below; an exhaust path provided below the support portion and capable of communicating with a space located below the safety valve; a cooler disposed below the power storage stack and configured to cool the power storage stack; an upper member that covers the electricity storage stack from above; an adhesive disposed between the upper surface of each of the plurality of storage cells and the upper member.

6. a lower case including a bottom wall portion located below the power storage stack, the support portion is formed by a part of the bottom wall portion, The power storage device according to claim 1 , wherein the cooler is disposed below the bottom wall portion.

7. a lower case including a bottom wall portion located below the power storage stack; a path defining member disposed between the bottom wall portion and the power storage stack, the path defining member defining the exhaust path together with the bottom wall portion, the cooler is disposed between the power storage stack and the path defining member, The power storage device according to claim 1 , wherein the support portion includes the path defining member and the cooler.

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