Electric storage device

Abstract

Provided is a power storage device that can reduce the influence of radiant heat from one power storage cell to the other while suppressing an increase in weight, in a configuration where a first power storage cell and a second power storage cell are arranged such that a cross member is positioned therebetween. 【Solution means】The power storage device 10 includes a first power storage cell 211 and a second power storage cell 221 arranged side by side in a first direction, a housing case, and a cross member 40 that extends along a second direction orthogonal to the first direction and is disposed in a gap between the first power storage cell 211 and the second power storage cell 221. The case includes a pair of side walls arranged side by side in the second direction, and the cross member 40 is connected to the pair of side walls at both ends in the second direction. A hollow portion H is provided in the cross member 40. The cross member 40 has a first wall portion 41 facing the first power storage cell 211 and a partition wall 45 that intersects the first direction and partitions the hollow portion H. The thickness of the partition wall 45 is equal to or less than the thickness of the first wall portion 41.

Description

Technical Field

[0001] The present disclosure relates to a power storage device.

Background Art

[0002] As a conventional power storage device, Japanese Unexamined Patent Application Publication No. 2023-165300 (Patent Document 1) is provided with a cross member that divides the space inside the battery case into a plurality of regions, and a power storage module is arranged in each of the plurality of regions.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Generally, a power storage module includes a plurality of power storage cells. When one power storage cell generates heat, radiant heat may be transmitted to other power storage cells.

[0005] In the power storage device described in Patent Document 1, a cross member is arranged between adjacent power storage modules. However, if there is no measure for the cross member, most of the radiant heat from the power storage cells included in one of the adjacent power storage modules passes through the cross member. In this case, the radiant heat may increase the temperature of the power storage cells included in the other of the adjacent power storage modules.

[0006] 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 device that can improve the rigidity of a case while suppressing an increase in weight and reduce the influence of radiant heat from one power storage cell to the other power storage cell in a configuration where a first power storage cell and a second power storage cell are arranged such that a cross member is positioned therebetween.

Means for Solving the Problems

[0007] A power storage device according to the present disclosure includes a first power storage cell and a second power storage cell arranged side by side with a space therebetween in a first direction, a housing case that houses the first power storage cell and the second power storage cell, and a cross member that extends along a second direction orthogonal to the first direction and the vertical direction and is disposed between the first power storage cell and the second power storage cell. The case includes a pair of side walls that extend along the first direction and are arranged side by side in the second direction. The cross member is connected to each of the pair of side walls at both ends in the second direction. The cross member is provided with a hollow portion in a cross section perpendicular to the second direction. The cross member has a first wall portion that faces the first power storage cell in the first direction and a partition wall that intersects the first direction in the cross section and partitions the hollow portion. The thickness of the partition wall is equal to or less than the thickness of the first wall portion.

[0008] According to the above configuration, the hollow portion of the cross member is partitioned by a partition wall that intersects the first direction in which the first power storage cell and the second power storage cell are arranged side by side. The partition wall can suppress the transmission of radiant heat from one of the first power storage cell and the second power storage cell to the other. Thereby, the influence of radiant heat from the one power storage cell to the other power storage cell can be reduced. In addition, since both ends of the cross member in the second direction are connected to the respective pair of side walls of the case, the rigidity of the case is improved. As a result, the durability of the case against impacts from the side of the power storage device can be improved.

[0009] In the power storage device based on the present disclosure, the projected area of the partition wall in the first direction may be 25% or more and 100% or less of the projected area of the first wall portion in the first direction.

[0010] According to the above configuration, by setting the projected area of the partition wall as described above, it is possible to suppress an increase in the weight of the cross member and reduce the influence of radiant heat from one power storage cell to the other power storage cell.

[0011] In the power storage device based on the present disclosure, the smaller angle among the intersection angles at which the first direction and the partition wall intersect may be 45 degrees or more and less than 90 degrees, or the intersection angle may be 90 degrees.

[0012] When the intersection angle is as described in the above configuration, one power storage cell can effectively reflect the radiant heat from one power storage cell to the other power storage cell toward the side where one power storage cell is located. Thereby, the influence of radiant heat from one power storage cell to the other power storage cell can be reduced.

[0013] In the power storage device based on the present disclosure, the first power storage cell may have a first exhaust valve. The first exhaust valve may face the cross member in the first direction.

[0014] According to the above configuration, by first discharging the emissions discharged from the first exhaust valve toward the cross member, it is possible to suppress the emissions from scattering while in a high-temperature state.

[0015] In the power storage device based on the present disclosure, the second power storage cell may have a second exhaust valve. The second exhaust valve may face the cross member in the first direction.

[0016] According to the above configuration, by first discharging the emissions discharged from the second exhaust valve toward the cross member, it is possible to suppress the emissions from scattering while in a high-temperature state.

[0017] In the power storage device based on the present disclosure, when viewed from the first direction, the first exhaust valve may be arranged so as to overlap the partition wall.

[0018] According to the above configuration, when the first exhaust valve and the partition wall overlap in the first direction, it is possible to suppress the radiant heat from the second power storage cell side from being transmitted to the first exhaust valve, which is relatively vulnerable to heat compared to other members constituting the first power storage cell.

[0019] In the power storage device based on the present disclosure, a first opening may be provided in the first wall portion at a position facing the first exhaust valve.

[0020] According to the above configuration, when emissions are discharged from the first exhaust valve, the emissions can be introduced into the cross member through the first opening. As a result, the emissions can be retained inside the cross member, and the scattering of the emissions can be suppressed.

[0021] In the power storage device based on the present disclosure, the first opening may be covered with a breakable heat insulating member.

[0022] According to the above configuration, when emissions are discharged from the first exhaust valve of the first power storage cell, the heat insulating member is broken by the momentum of the discharged emissions. As a result, the emissions can be introduced into the cross member through the first opening. Thereby, the emissions can be retained inside the cross member, and the scattering of the emissions can be suppressed. On the other hand, when emissions are discharged from the second power storage cell, the heat insulating member can suppress the heat from the first opening toward the first power storage cell, and the temperature rise of the first power storage cell can be suppressed.

[0023] In the power storage device based on the present disclosure, the heat insulating member may have an easily breakable portion.

[0024] According to the above configuration, when emissions are discharged from the first exhaust valve of the first power storage cell, the heat insulating member can be easily broken.

[0025] In the power storage device based on the present disclosure, the easily breakable portion may be configured by a breaking line. In this case, the first exhaust valve may be arranged to face the breaking line in the first direction.

[0026] According to the above configuration, when emissions are discharged from the first exhaust valve of the first power storage cell, the heat insulating member can be broken more reliably.

[0027] In the power storage device based on the present disclosure, the cross member may be provided with a communication portion that communicates the hollow portion with the space around the cross member. The communication portion may be provided at a position that does not face the first exhaust valve.

[0028] According to the above configuration, by discharging the gas contained in the emissions introduced from the first opening into the interior of the cross member from the communication portion, it is possible to suppress the internal pressure of the cross member from rising excessively due to the gas introduced from the first opening into the interior of the cross member.

[0029] The power storage device based on the present disclosure may further include a bottom surface defining portion that defines the bottom surface of the hollow portion. The end portion of the partition wall located on the side of the bottom surface defining portion is a free end, and a gap may be provided between the free end and the bottom surface defining portion.

[0030] According to the above configuration, the emissions from the exhaust valve introduced into the interior of the cross member through the first opening can be stored in the gap. Also, the storage amount of the emissions can be ensured sufficiently, and it is possible to suppress the emissions from scattering into the space around the first power storage cell.

[0031] In the power storage device based on the present disclosure, in the vertical direction orthogonal to the first direction and the second direction, the communication portion may be provided above the first exhaust valve.

[0032] According to the above configuration, when the gas contained in the exhaust introduced into the cross member from the first opening is discharged from the communication portion, it can be discharged above the first exhaust valve.

[0033] In the power storage device according to the present disclosure, the height of the cross member in the vertical direction may be higher than the heights of the first power storage cell and the second power storage cell in the vertical direction. The communication portion may be provided above the first power storage cell and the second power storage cell.

[0034] According to the above configuration, when the gas contained in the exhaust introduced into the cross member from the first opening is discharged from the communication portion, it can be discharged above the first power storage cell and the second power storage cell. Thereby, it is possible to suppress the gas from the communication portion from hitting the first power storage cell and the second power storage cell, and it is possible to suppress the temperature rise of the first power storage cell and the second power storage cell due to the gas blown out from the communication portion.

[0035] In the power storage device according to the present disclosure, the cross member may have an upper wall portion in the vertical direction. The communication portion may be provided on the upper wall portion.

[0036] According to the above configuration, when the gas contained in the exhaust introduced into the cross member from the first opening is discharged from the communication portion, it is discharged upward from the upper wall portion. Thereby, it is possible to suppress the gas from the communication portion from hitting the first power storage cell and the second power storage cell, and it is possible to suppress the temperature rise of the first power storage cell and the second power storage cell due to the gas blown out from the communication portion.

[0037] In the power storage device according to the present disclosure, the partition wall may have a plurality of wall portions arranged at intervals in the first direction.

[0038] According to the above configuration, since the partition wall includes a plurality of wall portions, it is possible to further suppress the transmission of radiant heat from one of the first power storage cell and the second power storage cell to the other.

[0039] In the power storage device based on the present disclosure, a region having a reflectance greater than that of the first wall portion may be provided on at least a part of the partition wall.

[0040] According to the above configuration, by providing a region having a high reflectance on at least a part of the partition wall, the transmission of radiant heat from one of the first power storage cell and the second power storage cell to the other power storage cell can be further suppressed.

[0041] The power storage device based on the present disclosure further includes a third power storage cell disposed on the side opposite to the side where the second power storage cell is located with respect to the first power storage cell in the first direction, and a cooler disposed in a gap between the first power storage cell and the third power storage cell for cooling the first power storage cell and the third power storage cell.

[0042] According to the above configuration, even when heat is transferred from the second power storage cell to the first power storage cell, the first power storage cell can be cooled by the cooler, and the transfer of the heat to the third power storage cell can be suppressed by the cooler disposed between the first power storage cell and the third power storage cell.

Effect of the Invention

[0043] According to the present disclosure, in a configuration in which the first power storage cell and the second power storage cell are arranged such that the cross member is located therebetween, it is possible to provide a power storage device that can suppress an increase in weight, improve the rigidity of the case, and reduce the influence of radiant heat from one power storage cell to the other power storage cell.

Brief Description of the Drawings

[0044]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Embodiments for Carrying Out the Invention

[0045] Hereinafter, embodiments and modifications of the present disclosure will be described in detail with reference to the drawings. In the embodiments and modifications shown below, the same or common parts are denoted by the same reference numerals in the drawings, and the description thereof will not be repeated.

[0046] In the embodiments and modifications described below, when referring to the number, quantity, etc., unless otherwise specified, the scope of the present disclosure is not necessarily limited to the number, quantity, etc. Also, in the following embodiments and modifications, each component is not necessarily essential for the present disclosure, unless otherwise specified. Further, when there are a plurality of embodiments and modifications below, unless otherwise specified, it is initially planned to appropriately combine the characteristic parts of each embodiment and modification.

[0047] (Embodiment 1) FIG. 1 is a schematic view of a vehicle including a power storage device according to Embodiment 1. FIG. 2 is a view showing a state in which the power storage device according to Embodiment 1 is fixed to the vehicle. With reference to FIGS. 1 and 2, the vehicle 1 according to Embodiment 1 will be described.

[0048] The vehicle 1 is a hybrid vehicle capable of traveling using at least one of the powers of a motor and an engine, or an electric vehicle that travels with a driving force obtained from electric energy.

[0049] 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 skeletal 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 part of the power storage device 10 may be disposed so as to overlap the front wheels 3 and / or 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 vehicle interior.

[0050] The skeletal 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 with a distance therebetween. The pair of side members 6 and the pair of side sills 7 extend along the longitudinal direction of the vehicle 1.

[0051] The pair of side members 6 are spaced apart in the width direction of the vehicle 1. The main body portion 35 of the power storage device 10 is arranged in the gap between the pair of side members 6. A gap is provided between the main body portion 35 and the pair of side members 6. Thereby, even when the vehicle 1 is side-collided, it is possible to suppress an impact from being input to the power storage device 10.

[0052] 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.

[0053] The skeletal member 5 also includes a cross skeletal member 9. The cross skeletal member 9 is provided so as to span from one side sill 7 to the other side sill 7 above the power storage device 10. The upper surface 10a of the power storage device 10 is fixed to the cross skeletal member 9.

[0054] In the above description, the case where the skeletal member 5 includes a pair of side members 6 and a pair of side sills 7 has been exemplified and described, but it is not limited thereto. The pair of side sills 7 may also have the functions of the pair of side members 6. In this case, the pair of side members 6 can be omitted, and the above-described fixed portions 36 may be fixed to the pair of side sills 7.

[0055] FIG. 3 is a plan view showing the inside of the power storage device according to Embodiment 1. With reference to FIG. 3, the details of the power storage device 10 will be described.

[0056] As shown in FIG. 3, the power storage device 10 includes a plurality of power storage modules 20, a housing case 30, a plurality of cross members 40, and an electronic device 95.

[0057] The plurality of power storage modules 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 at intervals in a first direction (DR1 direction). In the present embodiment, the first direction is parallel to, for example, the longitudinal direction of the vehicle 1 in a mounted state where the power storage device 10 is mounted on the vehicle body 2.

[0058] The first power storage stack 21 includes a plurality of first power storage cells 211. The plurality of first power storage cells 211 are arranged in a second direction (DR2 direction) orthogonal to the first direction. In the present embodiment, the second direction is parallel to, for example, the width direction of the vehicle 1 in the mounted state. The second power storage stack 22 includes a plurality of second power storage cells 221. The plurality of second power storage cells 221 are arranged side by side in the second direction.

[0059] The first power storage cell 211 and the second power storage cell 221 have a longitudinal shape with the first direction as the longitudinal direction. The first power storage cell 211 and the second power storage cell 221 have a flat rectangular parallelepiped shape with a thickness in the second direction.

[0060] The first power storage cell 211 and the second power storage cell 221 may be composed of the same power storage cell. In this case, the number of components can be reduced and the manufacturing cost can be reduced. Note that the term "same" includes those including manufacturing errors such as tolerances. Also, the first power storage cell 211 and the second power storage cell 221 may be composed of different power storage cells.

[0061] The first power storage cell 211 includes a housing 212 (see FIG. 4), and the second power storage cell 221 includes a housing 222 (see FIG. 4). Inside each of the housings 212 and 222, one or a plurality of electrode bodies 25 are accommodated. The housing 212 has a pair of side wall portions 214 and 213 arranged in the first direction. The side wall portion 214 is located on one side in the first direction, and the side wall portion 213 is located on the other side in the first direction. The housing 222 has a pair of side wall portions 223 and 224 arranged in the first direction. The side wall portion 223 is located on one side in the first direction, and the side wall portion 224 is located on the other side in the first direction.

[0062] When a single electrode body 25 is accommodated in the housings 212 and 222, the electrode body has a shape extending 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 a wound electrode body in which a negative electrode sheet, a separator, and a positive electrode sheet are wound.

[0063] When a plurality of electrode bodies are accommodated in the housings 212 and 222, the plurality of electrode bodies are arranged side by side in the longitudinal direction and are connected in series. Also in this case, the electrode body may be a laminated electrode body or a wound electrode body.

[0064] The first power storage cell 211 and the second power storage cell 221 are secondary batteries such as nickel-metal hydride batteries or lithium-ion batteries. The first power storage cell 211 and the second power storage cell 221 may use a liquid electrolyte or a solid electrolyte. The first power storage cell 211 and the second power storage cell 221 may be rechargeable capacitors.

[0065] The housing case 30 includes an upper member 31 (see FIG. 4) and a lower member 32. The lower member 32 has a substantially box-shaped configuration 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 front wall portion 322, a rear wall portion 323, and side wall portions 324, 325. The front wall portion 322, the rear 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.

[0066] The front wall portion 322 and the rear wall portion 323 face each other in the first direction. The side wall portions 324, 325 face each other in the second direction. The fixed portion 36 is provided on the outer surfaces of the side wall portions 324, 325.

[0067] A plurality of cross members 40 are provided so as to partition the accommodation space within the housing case 30. Specifically, the cross members 40 are provided so as to extend in the second direction. In the present embodiment, the accommodation space within the housing case 30 is divided into three parts in the first direction by two cross members 40.

[0068] In each of the three divided regions, an electronic device 95, a first power storage stack 21, and a second power storage stack 22 are arranged in order from one side in the first direction. A cross member 40 is arranged in the gap between the electronic device 95 and the first power storage stack 21, and a cross member 40 is arranged in the gap between the first power storage stack 21 and the second power storage stack 22.

[0069] Note that the number of the cross members 40 is not limited to two, and may be one or three or more as long as it is arranged in the gap between the mutually adjacent first power storage stack 21 and second power storage stack 22. The cross member 40 is constituted by a metal member such as SUS, for example. Further, the cross member 40 may be constituted by, for example, a high-tensile material. By configuring the cross member 40 with a high-tensile material, the rigidity of the power storage device 10 can be improved.

[0070] Among the plurality of cross members 40, at least the cross member disposed in the gap between the first power storage stack 21 and the second power storage stack 22 is provided with a hollow portion H (see FIG. 4). Note that all of the plurality of cross members 40 may be provided with the hollow portion H. The hollow portion H may form part of the smoke exhaust path for the gas discharged when any of the power storage cells included in the first power storage stack 21 and the second power storage stack 22 generates heat.

[0071] 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 insulating properties. The upper member 31 has, for example, a substantially flat plate shape. Note that the upper member 31 is not limited to the flat plate shape and may be a substantially box-shaped shape that opens downward.

[0072] The electronic device 95 controls the plurality of power storage modules 20. The electronic device 95 is, for example, a battery ECU.

[0073] FIG. 4 is a cross-sectional view taken along line IV-IV shown in FIG. 3, and more specifically, is a cross-sectional view showing the cross member and its peripheral structure. In FIG. 4, for convenience, the upper member of the housing case 30 is also shown. With reference to FIG. 4, the details of the cross member 40 and its peripheral structure will be described.

[0074] As described above, the cross member 40 is provided with the hollow portion H in a cross section perpendicular to the second direction. The hollow portion H is provided so as to continuously extend in the second direction. The cross member 40 includes a first wall portion 41, a second wall portion 42, an upper wall portion 43, a bottom wall portion 44, and a partition wall 45.

[0075] The first wall portion 41 is located on one side in the first direction. The first wall portion 41 faces the first power storage cell 211 in the first direction. The second wall portion 42 is located on the other side in the first direction. The second wall portion 42 faces the second power storage cell 221 in the first direction. The heights of the first wall portion 41 and the second wall portion 42 in the vertical direction (up and down direction) are higher than those of the first power storage cell 211 and the second power storage cell 221. The vertical direction is a direction orthogonal to the above-described first direction and second direction.

[0076] Note that the heights of the first wall portion 41 and the second wall portion 42 may be the same as the heights of the first power storage cell 211 and the second power storage cell 221.

[0077] The upper wall portion 43 and the bottom wall portion 44 face each other in the vertical direction. The upper wall portion 43 connects the upper ends of the first wall portion 41 and the second wall portion 42. The bottom wall portion 44 connects the lower ends of the first wall portion 41 and the second wall portion 42. The bottom wall portion 44 functions as a bottom surface defining portion that defines the bottom surface of the hollow portion H. The bottom wall portion 44 is fixed to the bottom wall portion 321 of the housing case 30.

[0078] The partition wall 45 is disposed between the first wall portion 41 and the second wall portion 42. The partition wall 45 is provided so as to intersect the first direction. More specifically, the partition wall 45 is orthogonal to the first direction. The partition wall 45 partitions the hollow portion H. The partition wall 45 extends in the second direction. The partition wall 45 is provided so as to overlap the first power storage stack 21 and the second power storage stack 22 in the second direction when viewed from the first direction. The partition wall 45 may be provided so as to extend from one end of the cross member 40 in the second direction to the other end of the cross member 40 in the second direction.

[0079] In the present embodiment, the partition wall 45 is provided so as to connect the upper wall portion 43 and the bottom wall portion 44, but the height of the partition wall 45 is not limited thereto. As will be described later, it can be appropriately set as long as it can suppress the transmission of radiant heat from one of the first power storage cell 211 and the second power storage cell 221 to the other.

[0080] The thickness T1 of the partition wall 45 is equal to or less than the thickness T2 of the first wall portion 41. Note that the thickness direction is the normal direction of the widest surface of the partition wall 45. In the embodiment, the thickness direction is parallel to the first direction. The thickness T2 of the first wall portion 41 may be the same as or different from the thickness of the second wall portion 42.

[0081] The housing 212 of the first power storage cell 211 has a side wall portion 213 facing the first wall portion 41 in the first direction. An external terminal 213A and a first exhaust valve 216 are provided on the side wall portion 213.

[0082] The first exhaust valve 216 is a valve for discharging emissions from inside the first power storage cell 211. The emissions contain gas. Further, the emissions may contain foreign substances such as electrolytes and metal foreign objects. The first exhaust valve 216 functions as a pressure relief valve. The first exhaust valve 216 is provided so as to break when the internal pressure of the housing 212 becomes a predetermined value or more. The first exhaust valve 216 is provided, for example, at the center of the side wall portion 213 in the vertical direction.

[0083] The first exhaust valve 216 faces the cross member 40 (more specifically, the first wall portion 41) in the first direction. The first exhaust valve 216 is arranged so as to overlap the partition wall 45 when viewed from the first direction.

[0084] The external terminal 213A is arranged, for example, above the first exhaust valve 216. The external terminal 213A faces the first wall portion 41 in the first direction.

[0085] The housing 222 of the second power storage cell 221 has a side wall portion 223 facing the second wall portion 42 in the first direction. An external terminal 223A and a second exhaust valve 226 are provided on the side wall portion 223. The side wall portion 223 is arranged so as to face the side wall portion 213 side in the first direction. The cross member 40 is located between the side wall portion 223 and the side wall portion 213.

[0086] The second exhaust valve 226 is a valve for discharging the above-described emissions from within the second power storage cell 221. The second exhaust valve 226 functions as a pressure release valve. The second exhaust valve 226 is provided so as to break when the internal pressure of the housing 222 becomes equal to or higher than a predetermined value. The second exhaust valve 226 is provided, for example, at the central portion of the side wall portion 223 in the vertical direction.

[0087] The second exhaust valve 226 faces the cross member 40 (more specifically, the second wall portion 42) in the first direction. The second exhaust valve 226 is arranged so as to overlap the partition wall 45 when viewed from the first direction.

[0088] The external terminal 223A is arranged, for example, above the second exhaust valve 226. The external terminal 223A faces the second wall portion 42 in the first direction.

[0089] When the power storage cells included in the plurality of power storage modules 20 generate heat, that is, when one of the first power storage cell 211 and the second power storage cell 221 generates heat, the above-described exhaust valve provided in the one power storage cell (specifically, the first exhaust valve 216 or the second exhaust valve 226) breaks, and emissions containing high-temperature gas are discharged into the storage case 30. In this state, one of the power storage cells has a considerably high temperature, and radiant heat is radiated from the one power storage cell toward the other of the first power storage cell 211 and the second power storage cell 221.

[0090] Here, in the present embodiment, the hollow portion H of the cross member 40 is partitioned by a partition wall 45 that intersects the first direction in which the first power storage cell 211 and the second power storage cell 221 are arranged. By means of the partition wall 45, transmission of radiant heat from the one power storage cell toward the other power storage cell can be suppressed. Specifically, for example, when the reflectance of the partition wall 45 is 0.5, the heat flux from the one power storage cell toward the other power storage cell can be reduced to 1 / 6 as compared with a configuration in which the partition wall 45 is not provided. In this way, the influence of radiant heat from the one power storage cell on the other power storage cell can be reduced.

[0091] Furthermore, by setting the thickness T1 of the partition wall 45 to be less than or equal to the thickness T2 of the first wall portion 41, an increase in the weight of the cross member 40 can be suppressed, and thus an increase in the weight of the power storage device 10 can be suppressed. The relationship between the thicknesses T1 and T2 as described above is suitable for an environment where it is required to suppress an increase in weight from the viewpoint of fuel efficiency and the like.

[0092] Also, as described above, the first exhaust valve 216 and the second exhaust valve 226 are arranged so as to face the cross member 40. Thus, when emissions are discharged from the first exhaust valve 216 or the second exhaust valve 226, the discharged emissions can be first discharged toward the cross member 40. Thereby, it is possible to suppress the emissions from scattering while in a high-temperature state. At this time, since the external terminals 213A and 223A are located above the first exhaust valve 216 and the second exhaust valve 226, it is possible to suppress the adhesion of emissions to the external terminals 213A and 223A.

[0093] In addition, as described above, since the first exhaust valve 216 and the second exhaust valve 226 and the partition wall 45 overlap in the first direction, when emissions are discharged from the one power storage cell, it is possible to suppress radiant heat from being transmitted to the first exhaust valve 216 or the second exhaust valve 226, which is vulnerable to heat.

[0094] Also, at least a part of the partition wall 45 may be provided with a region having a higher reflectivity than the first wall portion 41. The region is subjected to surface treatment, and for example, a reflective film or the like is provided. The reflective film may be made of a resin material or a metal material such as aluminum. In such a case, the transmission of radiant heat from the one power storage cell toward the other power storage cell can be further suppressed.

[0095] In the above-described Embodiment 1, the case where the first exhaust valve 216 is provided on the side wall portion 213 facing the second power storage cell 221 in the housing 212 has been described as an example, but the present invention is not limited thereto. In the housing 212, the first exhaust valve 216 may be provided on the side wall portion 214. The side wall portion 214 faces the side opposite to the side where the second power storage cell 221 is located. More specifically, the side wall portion 214 faces the side where the electronic device 95 is located.

[0096] In this case, the above-described cross member 40 is disposed between the electronic device 95 and the first power storage cell 221 (more specifically, the first power storage stack 21). When the first power storage cell 221 generates heat, it is possible to suppress the radiant heat from the first power storage cell 221 from being transmitted to the electronic device 95. Thereby, an increase in the temperature of the electronic device 95 can be suppressed.

[0097] Further, when the first exhaust valve 216 faces the cross member 40 disposed between the first power storage stack 21 and the electronic device 95 in the first direction, the exhaust discharged from the first exhaust valve can be first discharged toward the cross member 40. As a result, it is possible to suppress the exhaust from scattering while in a high-temperature state. In the above case, the second exhaust valve 216 may be provided on the side wall portion 223 or may be provided on the side wall portion 224.

[0098] (First Modified Example) FIG. 5 is a cross-sectional view showing a cross member and its peripheral structure according to the first modified example. Note that in the power storage device 10A according to the first modified example, the shape of the cross member 40A is changed as compared with Embodiment 1. Other configurations are substantially the same.

[0099] In the cross member 40A according to the first modified example, the partition wall 45 intersects the first direction (DR1 direction). The smaller angle θ of the intersection angle between the first direction and the partition wall 45 is 45 degrees or more and less than 90 degrees. Note that in Embodiment 1, the intersection angle θ is 90 degrees.

[0100] By setting the crossing angle as described above, the radiant heat traveling from one of the power storage cells to the other power storage cell can be effectively reflected toward the side where one of the power storage cells is located. More specifically, the radiant heat can be reflected so as to be parallel to the first direction and not include a component directed toward the other power storage cell. Thereby, also in the first modification example, the influence of the radiant heat from one power storage cell to the other power storage cell can be reduced.

[0101] In addition, within the range of the crossing angle θ, when the crossing angle θ is large (for example, when the crossing angle θ is 60 degrees or more and 90 degrees or less), the area of the partition wall 45 becomes larger, so that the influence of the radiant heat can be further reduced.

[0102] Also, within the range of the crossing angle θ, when the value of the crossing angle θ is small (for example, when the crossing angle θ is 45 degrees or more and less than 60 degrees), the area of the partition wall 45 can be made smaller, so that while further suppressing an increase in weight, the influence of the radiant heat can be further reduced.

[0103] In the above description, the case where the partition wall 45 is inclined upward as it approaches the second wall portion 42 is illustrated, but the present invention is not limited thereto, and it may be inclined downward as it approaches the second wall portion 42.

[0104] (Second Modification Example) FIG. 6 is a cross-sectional view showing a cross member and its peripheral structure according to the second modification example. Note that the power storage device 10B according to the second modification example has a different projected area of the cross member 40B compared to the first embodiment. Other configurations are substantially the same.

[0105] The cross member 40B according to the second modification example has a different ratio of the projected area S1 of the partition wall 45 in the first direction to the projected area S2 of the first wall portion 41 in the first direction. In the second modification example, the case where the partition wall 45 intersects the first wall portion 41 is illustrated, but it may be parallel to the first wall portion 41.

[0106] In Embodiment 1, the above-mentioned projected area S1 is 100% of the above-mentioned projected area S2. However, in Modification 2, the above-mentioned projected area S1 is 25% or more and less than 100% of the above-mentioned projected area S2.

[0107] When the configuration of the second modification and the configuration of Embodiment 1 are combined, the above-mentioned projected area S1 may be 25% or more and 100% or less of the above-mentioned projected area S2. Further, the above-mentioned projected area S1 may be 50% or more and 100% or less of the above-mentioned projected area S2. Furthermore, the above-mentioned projected area S1 may be 75% or more and 100% or less of the above-mentioned projected area S2.

[0108] When the above-mentioned projected area S1 is less than 25% of the above-mentioned projected area S2, the ratio of the radiant heat from one power storage cell to the other power storage cell passing through the cross member increases. However, when the above-mentioned projected area S1 is 25% or more of the above-mentioned projected area S2, the transmission of the radiant heat can be suppressed to a considerable extent by the partition wall 45. When the above-mentioned projected area S1 is 50% or more of the above-mentioned projected area S2, the transmission of the radiant heat can be effectively suppressed by the partition wall 45. When the above-mentioned projected area S1 is 75% or more of the above-mentioned projected area S2, the transmission of the radiant heat can be more reliably suppressed by the partition wall 45.

[0109] In addition, in the above, when the projected area S1 is small, by arranging the partition wall 45 so that the first exhaust valve 216 and the second exhaust valve 226 overlap in the first direction, even if the partition wall 45 is small, the influence of the radiant heat from the one power storage cell to the other power storage cell can be effectively reduced.

[0110] (Embodiment 2) FIG. 7 is an exploded perspective view of a power storage device according to Embodiment 2. With reference to FIG. 7, the power storage device 10C according to Embodiment 2 will be described.

[0111] The power storage device 10C according to Embodiment 2 is mainly different from the power storage device 10 according to Embodiment 1 in that the arrangement and structure of a plurality of power storage modules 20 and cross members 40 are different, and in that it includes a partition wall 50. Other configurations are substantially the same.

[0112] In Embodiment 2, in the mounted state where the power storage device 10C is mounted on the vehicle body 2, the first direction is parallel to the width direction of the vehicle 1, and the second direction is parallel to the longitudinal direction of the vehicle 1.

[0113] The plurality of power storage modules 20 are arranged in a matrix in the first direction and the second direction. In the housing case 30, the region where each power storage module 20 is arranged is partitioned by a plurality of cross members 40 and a plurality of partition walls 50.

[0114] The cross members 40 are arranged side by side at intervals in the first direction. The cross members 40 are arranged in the gaps between the power storage modules 20 adjacent to each other in the first direction. The cross members 40 extend in the second direction. The cross members 40 extend from the front wall portion 322 to the rear wall portion 323 of the lower member 32 of the housing case 30.

[0115] The partition wall 50 partitions the space in the housing case 30 partitioned by the cross members 40 so as to correspond to the number of the plurality of power storage modules 20. The partition wall 50 extends in the first direction. The partition wall 50 may have a hollow structure.

[0116] An exhaust portion 80 is provided in the upper member 31 of the housing case 30. The exhaust portion 80 discharges the internal gas when the internal pressure in the housing case 30 becomes higher than a predetermined pressure. Specifically, when gas is discharged from the power storage cells included in the plurality of power storage modules 20 into the housing case 30 and the internal pressure in the housing case 30 becomes higher than a predetermined pressure, the gas is discharged to the outside of the housing case 30.

[0117] In addition, when the discharge part 80 is provided in the upper member 31 as in the present embodiment, the vehicle 1 has a structure such that the gas discharged from the discharge part 80 is not introduced into the interior of the vehicle 1.

[0118] FIG. 8 is a plan view showing the inside of the power storage device according to Embodiment 2. As shown in FIG. 8, among the power storage modules 20 adjacent to each other in the first direction, the power storage module 20 located on one side in the first direction includes the first power storage stack 21 and the third power storage stack 23. Among the power storage modules 20 adjacent to each other in the first direction, the power storage module 20 located on the other side in the first direction includes the second power storage stack 22 and the fourth power storage stack 24.

[0119] In the power storage module 20 located on one side in the first direction, the first power storage stack 21 and the third power storage stack 23 are arranged to face each other in the first direction.

[0120] The first power storage stack 21 has a plurality of first power storage cells 211. The plurality of first power storage cells 211 are arranged in the second direction. The first power storage cell 211 has a pair of side wall portions in the first direction, and external terminals 213A and 213B (see FIG. 9) having different curvatures are provided on the side wall portion 213 (see FIG. 9) located on the side closest to the cross member 40C. Among the pair of side wall portions, the side wall portion located on the side opposite to the side wall portion 213 is in thermal contact with a cooler 70 described later.

[0121] The third power storage stack 23 is arranged on the side opposite to the side where the second power storage stack 22 is located with respect to the first power storage stack 21. The third power storage stack 23 has a plurality of third power storage cells 231. The plurality of third power storage cells 231 are arranged in the second direction. The third power storage cell 231 is arranged on the side opposite to the side where the second power storage cell 221 included in the second power storage stack 22 is located with respect to the first power storage cell 211. The third power storage cell 231 includes a side wall portion on the side opposite to the side where the first power storage cell 211 is located, and external terminals having different polarities are provided on the side wall portion.

[0122] In the power storage module 20 located on the other side in the first direction, the second power storage stack 22 and the fourth power storage stack 24 are arranged to face each other in the first direction.

[0123] The second power storage stack 22 has a plurality of second power storage cells 221. The plurality of second power storage cells 221 are arranged in the second direction. The second power storage cell 221 has a pair of side wall portions in the first direction, and on the side wall portion 223 (see FIG. 9) located on the side of the closest cross member 40C, external terminals 223A and 223B (see FIG. 9) with different curvatures from each other are provided. Among the pair of side wall portions, the side wall portion located on the side opposite to the side wall portion 223 is in thermal contact with a cooler 70 described later.

[0124] The fourth power storage stack 24 is arranged on the side opposite to the side where the first power storage stack 21 is located with respect to the second power storage stack 22. The fourth power storage stack 24 has a plurality of fourth power storage cells 241. The plurality of fourth power storage cells 241 are arranged in the second direction. The fourth power storage cell 241 is arranged on the side opposite to the side where the first power storage cell 211 included in the first power storage stack 21 is located with respect to the second power storage cell 221. The fourth power storage cell 241 includes a side wall portion on the side opposite to the side where the second power storage cell 221 is located, and external terminals with different polarities from each other are provided on the side wall portion.

[0125] The first power storage cell 211, the second power storage cell 221, the third power storage cell 231, and the fourth power storage cell 241 have substantially the same configuration. The first power storage cell 211, the second power storage cell 221, the third power storage cell 231, and the fourth power storage cell 241 have a flat rectangular tube shape in the second direction.

[0126] The power storage device 10C includes a cooler 70. The cooler 70 is provided in each power storage module 20. The cooler 70 is disposed between the power storage stacks adjacent to each other in the second direction in each power storage module 20 so as to cool both of the power storage stacks adjacent to each other in the second direction. For example, in the power storage module 20 located on one side in the first direction, the cooler 70 is sandwiched between the first power storage stack 21 and the third power storage stack 23 described above. Similarly, in the power storage module 20 located on the other side in the first direction, the cooler 70 is sandwiched between the second power storage stack 22 and the fourth power storage stack 24 described above. The cooler 70 has a refrigerant flow path through which a cooling medium flows inside.

[0127] FIG. 9 is a cross-sectional view taken along line IX-IX shown in FIG. 8. As shown in FIG. 9, a first exhaust valve 216 is provided in the side wall portion 213 of the first power storage cell 211 described above, and a second exhaust valve 226 is provided in the side wall portion 223 of the second power storage cell 221 described above.

[0128] Further, in the cross member 40C, a first opening 47 is provided in the first wall portion 41. The first opening 47 is provided so as to face the first exhaust valve 216. Therefore, when gas is discharged from the first exhaust valve 216, the gas can be introduced into the cross member 40C from the first opening 47. Thereby, the discharge products contained in the gas can be retained inside the cross member 40C, and the scattering of the discharge products can be suppressed.

[0129] The first opening 47 is covered with a breakable heat insulating member 60. The heat insulating member 60 faces the first exhaust valve 216 in the first direction.

[0130] The second wall portion 42 is provided with a second opening 48. The second opening 48 is provided so as to face the second exhaust valve 226. Therefore, when gas is discharged from the second exhaust valve 226, the gas can be introduced into the inside of the cross member 40C through the second opening 48. Thereby, the emissions contained in the gas can be retained inside the cross member 40C, and the scattering of the emissions can be suppressed.

[0131] The second opening 48 is covered by a breakable heat insulating member 60. The heat insulating member 60 faces the second exhaust valve 226 in the first direction.

[0132] The partition wall 45 is provided so as to stand up from the bottom wall portion 44. The partition wall 45 is provided so as not to reach the upper wall portion 43. The upper end of the partition wall 45 is located above the first opening 47 and the second opening 48.

[0133] Further, the cross member 40C is provided with a communication portion 49. Specifically, the communication portion 49 is provided, for example, on the upper wall portion 43. Note that the communication portion 49 may be provided above the first exhaust valve 216 and the second exhaust valve 226, or may be provided above the first power storage cell 211 and the second power storage cell 221.

[0134] The communication portion 49 communicates the hollow portion H with the space around the cross member 40. More specifically, the communication portion 49 communicates the hollow portion H with the space inside the housing case 30. The communication portion 49 extends along the second direction.

[0135] The cross member 40C has a first end portion and a second end portion at both ends in the second direction. The communication portion 49 continuously extends from the first end portion side toward the second end portion side.

[0136] Note that the communication part 49 may have a shape that intermittently extends in the second direction corresponding to each power storage module 20 arranged in the second direction. In this case, at the location corresponding to each power storage module 20 (specifically, the portion of the cross member 40 facing each power storage module 20), the length of the communication part 49 in the second direction is, for example, from the first exhaust valve located on one side in the second direction among the first exhaust valves 216 of the plurality of first power storage cells 211 to the first exhaust valve 216 located on the other side in the second direction among the first exhaust valves 216, and is equal to or greater than the length in the second direction.

[0137] FIG. 10 is a plan view of a heat insulating member that covers an opening of a cross member in a power storage device according to Embodiment 2.

[0138] As shown in FIG. 10, the heat insulating member 60 is provided in a sheet shape. The heat insulating member 60 is composed of, for example, a mica sheet. The heat insulating member 60 is provided with an easily breakable part 61. The easily breakable part 61 is composed of, for example, a breaking line. The breaking line is formed by through holes arranged in an annular or frame shape. In the heat insulating member 60, the first exhaust valve 216 or the second exhaust valve 226 faces the first direction in the region surrounded by the breaking line. Note that the first exhaust valve 216 or the second exhaust valve 226 may face the breaking line in the first direction.

[0139] Further, the heat insulating member 60 is not limited to a mica sheet, and may be composed of a heat insulating resin sheet having a lower strength than the mica sheet. In this case, the easily breakable part 61 may be omitted.

[0140] The heat insulating member 60 facing the first exhaust valve 216 is configured to be breakable by the exhaust discharged from the first exhaust valve 216. On the other hand, when no exhaust is discharged from the first exhaust valve 216 and exhaust is discharged from the second exhaust valve 226, it is preferable that the heat insulating member 60 facing the first exhaust valve 216 is not broken by the exhaust from the second exhaust valve 226.

[0141] Similarly, the heat insulating member 60 facing the second exhaust valve 226 is configured to be breakable by the exhaust discharged from the second exhaust valve 226. On the other hand, when no exhaust is discharged from the second exhaust valve 226 and exhaust is discharged from the first exhaust valve 216, it is preferable that the heat insulating member 60 facing the second exhaust valve 226 is not broken by the exhaust from the first exhaust valve 216.

[0142] FIG. 11 is a schematic cross-sectional view showing the movement of the exhaust discharged from the second power storage cell in the power storage device according to Embodiment 2.

[0143] As shown in FIG. 11, when exhaust is discharged from the second exhaust valve 226 of the second power storage cell 221, the heat insulating member 60 facing the second exhaust valve 226 is broken, and the exhaust is introduced into the cross member 40C. Since the heat insulating member 60 is provided with an easily breakable portion 61, the heat insulating member 60 is easily broken by the momentum of the exhaust. Further, since the second exhaust valve 226 faces the breaking line constituting the easily breakable portion 61 or the region surrounded by the breaking line, the heat insulating member 60 can be broken more reliably.

[0144] Since the partition wall 45 is arranged so that the second exhaust valve 226 overlaps in the first direction, the exhaust introduced from the second opening 48 can be first moved toward the partition wall 45. Thereby, while preventing the exhaust from directly heading toward the first power storage cell 211, it is possible to suppress the exhaust from scattering while remaining in a high-temperature state. Further, the exhaust can be collected at the lower part of the hollow portion H (more specifically, on the bottom wall portion 44 side of the cross member 40C). Thereby, it is possible to suppress the exhaust from scattering into the space in the housing case 30.

[0145] Furthermore, since the first opening 47 located on the side opposite to the second opening 48 is covered with the heat insulating member 60, the heat insulating member 60 can suppress the heat from the first opening 47 toward the first power storage cell 211. Thereby, the temperature rise of the first power storage cell 211 can be suppressed.

[0146] In addition, since the cross member 40C is provided with the communication portion 49 described above, the gas introduced into the cross member 40C is discharged through the communication portion 49 into the space around the cross member 40C (inside the housing case 30). Thereby, it is possible to suppress the excessive increase in the internal pressure of the cross member 40C.

[0147] If the internal pressure of the cross member 40C rises excessively while the internal pressure of the housing case 30 does not rise, the internal pressure of the housing case 30 may not reach a predetermined pressure and the discharge portion 80 provided in the upper member 31 may not be opened. Here, in the present embodiment, since the gas is discharged from the communication portion 49 into the housing case 30 as described above, the internal pressure in the housing case 30 rises, and the discharge portion 80 can be surely opened.

[0148] In addition, since the communication portion 49 is provided in the upper wall portion 43, the gas in the cross member 40C can be discharged upward. Thereby, it is possible to suppress the gas discharged from the communication portion 49 from directly hitting the power storage module 20 (the first power storage cell 211 and the second power storage cell 221). As a result, it is possible to suppress the temperature rise of the power storage module 20 due to the gas discharged from the communication portion 49. A gap is provided between the upper wall portion 43 and the upper member 31, and the gas is discharged toward the gap.

[0149] In the above description, the case where gas is discharged from the second power storage cell 221 has been described. However, when gas is discharged from the first power storage cell 211, substantially the same effects as described above can be obtained. For example, when gas is discharged from the first power storage cell 211, the heat insulating member 60 covering the first opening 47 breaks, and gas can be introduced into the first opening 47. Thereby, the above-described discharge product can be retained inside the cross member 40C, and it is possible to prevent the discharge product from scattering into the housing case 30. Further, since the second opening 48 located on the side opposite to the first opening 47 is covered with the heat insulating member 60, the heat from the second opening 48 toward the second power storage cell 221 can be suppressed. The effect of discharging the gas from the communication portion 49 is the same as described above.

[0150] Furthermore, also in Embodiment 2, a partition wall 45 is provided on the cross member 40C as in Embodiment 1. Thus, the power storage device 10C according to Embodiment 2 can obtain substantially the same effects as the power storage device 10 according to Embodiment 1.

[0151] In addition, as described above, since the cooler 70 is provided between the first power storage cell 211 and the third power storage cell 231, even if heat is transferred from the second power storage cell 221 side to the first power storage cell 211, the cooler 70 can cool the first power storage cell 211 and suppress the transfer of heat to the third power storage cell 231.

[0152] Similarly, since the cooler 70 is provided between the second power storage cell 221 and the fourth power storage cell 241, even if heat is transferred from the first power storage cell 211 side to the second power storage cell 221, the cooler 70 can cool the second power storage cell 221 and suppress the transfer of heat to the fourth power storage cell 241.

[0153] (Third Modification Example) FIG. 12 is a cross-sectional view showing a cross member and its peripheral structure according to the third modification example. With reference to FIG. 12, the power storage device 10D according to the third modification example will be described.

[0154] As shown in FIG. 12, the power storage device 10D according to the third modification example has a different configuration of the cross member 40D compared to the power storage device 10C according to Embodiment 2. Other configurations are substantially the same.

[0155] The cross member 40D is formed by bending a single plate-like member made of a metal such as SUS. The cross member 40D is manufactured by roll forming.

[0156] Specifically, the cross member 40D is formed by bending the single plate-like member so that the above-mentioned single plate-like member is continuous in the order of the partition wall 45, the first wall portion 41, the bottom wall portion 44, and the second wall portion 42. More specifically, the single plate-like member connects the lower end 45a of the partition wall 45, the upper end of the partition wall 45, the upper end of the first wall portion 41, the lower end of the first wall portion 41, the lower end of the second wall portion 42, and the upper end of the second wall portion 42 in order, and is bent from the upper end of the second wall portion 42 toward the upper end of the partition wall 45.

[0157] The upper wall portion 43 is constituted by a connecting portion connecting the upper end of the partition wall 45 and the upper end of the first wall portion 41, and a portion bent from the upper end of the second wall portion 42 toward the upper end of the partition wall 45. A gap is formed between the portion bent from the upper end of the second wall portion 42 toward the upper end of the partition wall 45 and the upper end of the partition wall 45, and the communication portion 49 is constituted by the gap.

[0158] The bottom wall portion 44 is constituted by a portion connecting the lower end of the first wall portion 41 and the lower end of the second wall portion 42. The bottom wall portion 44 functions as a bottom surface defining portion that defines the bottom surface of the hollow portion H, and a gap is formed between the bottom wall portion 44 and the lower end 45a of the partition wall 45. The lower end 45a of the partition wall 45 is a free end. The lower end 45a of the partition wall 45 is located at a position lower than the first exhaust valve 216 and the second exhaust valve 226.

[0159] Even when configured as described above, the power storage device 10D according to the third modification example can obtain substantially the same effects as the power storage device 10C according to the second embodiment. Specifically, similar to the second embodiment, since the partition wall 45 is arranged so as to overlap the first exhaust valve 216 or the second exhaust valve 226 in the first direction, the exhaust introduced from the first opening 47 or the second opening 48 can be first moved toward the partition wall 45. Thereby, while preventing the exhaust from directly heading toward the first power storage cell 211 or the second power storage cell 221, it is possible to suppress the exhaust from scattering while remaining in a high-temperature state. In addition, as described above, since a gap is formed between the partition wall 45 and the lower end 45a of the partition wall 45, the exhaust introduced from the first opening 47 or the second opening 48 into the inside of the cross member 40D can be stored (collected) in the gap. Also, a sufficient amount of the exhaust can be stored.

[0160] (Fourth Modification Example) FIG. 13 is a cross-sectional view showing a cross member and its peripheral structure according to the fourth modification example. With reference to FIG. 13, the power storage device 10E according to the fourth modification example will be described.

[0161] As shown in FIG. 13, the power storage device 10E according to the fourth modification example has different positions of the first exhaust valve 216, the second exhaust valve 226, the first opening 47, and the second opening 48 as compared with the power storage device 10D according to the third modification example. Other configurations are substantially the same.

[0162] The first exhaust valve 216 and the second exhaust valve 226 are arranged offset in the vertical direction when viewed from the first direction. Specifically, the first exhaust valve 216 is arranged above the central portion of the side wall portion 213 in the vertical direction. The second exhaust valve 226 is arranged below the central portion of the side wall portion 223 in the vertical direction.

[0163] The first exhaust valve 216 and the second exhaust valve 226 are correspondingly provided with a first opening 47 and a second opening 48 in the cross member 40E. Specifically, the first opening 47 is provided above the central portion of the first wall portion 41 in the vertical direction so as to face the first exhaust valve 216 in the first direction. The second opening 48 is provided below the central portion of the second wall portion 42 in the vertical direction so as to face the second exhaust valve 226 in the first direction.

[0164] Note that the first exhaust valve 216 and the first opening 47 may be provided on the lower side, and the second exhaust valve 226 and the second opening 48 may be arranged on the upper side.

[0165] Even in the case configured as above, the power storage device 10E according to the fourth modification example can obtain substantially the same effects as the power storage device 10D according to the third modification example. In addition, as described above, since the first opening 47 and the second opening 48 are displaced in the vertical direction when viewed from the first direction, even when gas is introduced from one of the first opening 47 and the second opening 48, it is possible to suppress the gas from directly heading toward the other opening.

[0166] (Fifth Modification Example) FIG. 14 is a cross-sectional view showing a cross member and its peripheral structure according to the fifth modification example. With reference to FIG. 14, the power storage device 10F according to the fifth modification example will be described.

[0167] As shown in FIG. 14, the power storage device 10F according to the fifth modification example has a different position of the communication portion 49 as compared with the power storage device 10C according to the second embodiment.

[0168] The height of the cross member 40C in the vertical direction is higher than the heights of the first power storage cell 211 and the second power storage cell 221 in the vertical direction, and the communication portion 49 is provided above the first power storage cell 211 and the second power storage cell 221. Specifically, the communication portion 49 is provided in portions of the first wall portion 41 and the second wall portion 42 that are located above the first power storage cell 211 and the second power storage cell 221. Note that the communication portion 49 may be provided in either one of the first wall portion 41 and the second wall portion 42.

[0169] Even in the case configured as described above, the power storage device 10F according to the fifth modification example can obtain substantially the same effects as the power storage device 10C according to the second embodiment. Further, when the cross member in the fifth modification example is adopted, when there is not enough clearance between the upper wall portion 43 of the cross member and the upper member 31, gas can be effectively discharged toward the space located above the first power storage cell 211 and the second power storage cell 221.

[0170] (Embodiment 3) FIG. 15 is an exploded perspective view of a power storage device according to Embodiment 3. With reference to FIG. 15, the power storage device 10G according to Embodiment 3 will be described.

[0171] As shown in FIG. 14, when the power storage device 10G according to Embodiment 3 is compared with the power storage device 10C according to Embodiment 2, the positions of the first exhaust valve 216, the second exhaust valve 226, the first opening 47, and the second opening 48 are different. The other configurations are substantially the same.

[0172] The first exhaust valves 216 provided in each of the plurality of first power storage cells 211 arranged in the second direction are arranged side by side vertically and alternately along the second direction. Accordingly, the plurality of first openings 47 provided corresponding to the plurality of first power storage cells 211 are also arranged side by side vertically and alternately along the second direction.

[0173] Similarly, the second exhaust valves 226 provided in each of the plurality of second power storage cells 221 arranged in the second direction are arranged alternately up and down along the second direction. Accordingly, the plurality of second openings 48 provided corresponding to the plurality of second power storage cells 221 are also arranged alternately up and down along the second direction.

[0174] In the first power storage cell 211 and the second power storage cell 221 facing the first direction, the first exhaust valve 216 and the second exhaust valve 226 are arranged offset in the vertical direction when viewed from the first direction.

[0175] Even in such a configuration, the power storage device 10G according to Embodiment 3 can obtain substantially the same effects as the power storage device 10C according to Embodiment 2.

[0176] (Embodiment 4) FIG. 16 is a plan view showing the inside of the power storage device according to Embodiment 4. With reference to FIG. 16, the power storage device 10H according to Embodiment 4 will be described.

[0177] When the power storage stack 10H according to Embodiment 4 is compared with the power storage stack 10 according to Embodiment 1, the arrangements of the cross members 40 and the electronic devices 96, 97 are different. The other configurations are substantially the same.

[0178] Two cross members 40 are arranged side by side in the first direction with a space therebetween between the first power storage stack 21 and the second power storage stack 22 arranged in the first direction, and the electronic devices 96, 97 are arranged between the two cross members 40.

[0179] That is, the first power storage stack 21 and the electronic devices 96 and 97 are arranged side by side in the first direction, and one cross member 40 is arranged between the first power storage stack 21 and the electronic devices 96 and 97. The electronic devices 96 and 97 and the second power storage stack 22 are arranged side by side in the first direction, and the other cross member 40 is arranged between the electronic devices 96 and 97 and the second power storage stack 22. The electronic device 96 controls the operation of the first power storage stack 21, for example, and the electronic device 97 controls the operation of the second power storage stack 22, for example. In the present embodiment, the case where two electronic devices 96 and 97 are provided is illustrated, but the number of electronic devices may be one or three or more.

[0180] Even in the case configured as described above, since the cross member 40 is arranged between the first power storage stack 21 and the second power storage stack 22, the power storage device 10H according to Embodiment 4 can obtain substantially the same effects as the device 1 according to Embodiment 1. Further, when any first power storage cell 211 included in the first power storage stack 21 or any second power storage cell 221 included in the second power storage stack 22 generates heat, it is possible to suppress the radiant heat from the first power storage cell 211 or the second power storage cell 221 from being transmitted to the electronic devices 96 and 97 and suppress the temperature rise of the electronic devices 96 and 97.

[0181] In the above description, the case where the electronic devices 96 and 97 are arranged between the first power storage stack 21 and the second power storage stack 22 has been illustrated and described, but the present invention is not limited to this. The electronic devices 96 and 97 may be arranged so that the cross member 40 is located between the first power storage stack 21 or the second power storage stack 22. As long as the electronic devices 96 and 97 are arranged in this way, one of the first power storage stack 21 or the second power storage stack 22 may be omitted.

[0182] (Embodiment 5) FIG. 17 is a cross-sectional view showing a cross member and its peripheral structure according to Embodiment 5. With reference to FIG. 17, the power storage device 10I according to Embodiment 5 will be described.

[0183] As shown in FIG. 17, the power storage device 10I according to Embodiment 5 has a different shape of the cross member 40 compared to the power storage device 10 according to Embodiment 1. For other configurations, they are substantially the same.

[0184] In Embodiment 5, the cross member 40 does not have a bottom wall portion, and has flange portions 41f and 42f provided so as to extend outward from the lower ends of the first wall portion 41 and the second wall portion 42. The flange portions 41f and 42f are fixed to the bottom wall portion 321 of the housing case 30. The flange portions 41f and 42f may be fixed to the bottom wall portion 321 by fastening members, or may be fixed to the bottom wall portion 321 by welding or the like. In this case, the portion of the bottom wall portion 321 of the housing case 30 that faces the upper wall portion 43 in the vertical direction functions as a bottom surface defining portion that defines the bottom surface of the hollow portion H.

[0185] Even in the case configured as above, the power storage device 10I according to Embodiment 5 can obtain substantially the same effects as the device 1 according to Embodiment 1.

[0186] Note that the configuration of the cross member having the flange portions 41f and 42f as shown in FIG. 17 may be applied to the cross members of Embodiments 2, 3, 4, as well as the first modification, the second modification, and the fifth modification.

[0187] (Other Modifications) In the above-described Embodiments 1, 2, 3, 4, 5, and the first modification to the fifth modification, the case where the first exhaust valve 216 and the second exhaust valve 226 are arranged to face the cross member is illustrated, but the present invention is not limited thereto. The first power storage cell 211 and the second power storage cell 221 may be arranged so that the first exhaust valve 216 and the second exhaust valve 226 do not face the cross member. In this case, by arranging the cross member as described above between the first power storage cell 211 and the second power storage cell 221, it is possible to reduce the influence of radiant heat from one power storage cell to the other power storage cell while suppressing an increase in weight.

[0188] In addition, other members such as a bus bar module or a bus bar cover may be interposed between the first power storage stack 21 or the second power storage stack 22 and the cross member. More specifically, a bus bar cover may be disposed between the first exhaust valve 216 or the second exhaust valve 226 and the cross member. In this case, when the bus bar cover is melted by the emissions discharged from the first exhaust valve 216 or the second exhaust valve 226, it is possible to suppress the scattering of the emissions passing through the melted portion by the cross member.

[0189] As described above, the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope equivalent to the claims.

Explanation of Reference Numerals

[0190] 1 Vehicle, 2 Vehicle body, 3 Front wheel, 4 Rear wheel, 5 Skeletal member, 6 Side member, 7 Side sill, 8 Fastening member, 9 Cross skeletal member, 10, 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H, 10I Power storage device, 10a Upper surface, 20 Power storage module, 21 First power storage stack, 22 Second power storage stack, 23 Third power storage stack, 24 Fourth power storage stack, 25 Electrode body, 30 Housing case, 31 Upper member, 32 Lower member, 35 Main body portion, 36 Fixed portion, 40, 40A, 40B, 40C, 40D, 40E Cross member, 41 First wall portion, 41f Flange portion, 42 Second wall portion, 42f Flange portion, 43 Upper wall portion, 44 Bottom wall portion, 45 Partition wall, 45a Lower end, 47 First opening, 48 Second opening, 49 Communication portion, 50 Partition wall, 60 Heat insulating member, 61 Easily breakable portion, 70 Cooler, 80 Discharge portion, 95 Electronic device, 211 First power storage cell, 212 Housing, 213 Side wall portion, 213A, 213B External terminal, 216 First exhaust valve, 221 Second power storage cell, 222 Housing, 223 Side wall portion, 223A, 223B External terminal, 226 Second exhaust valve, 231 Third power storage cell, 241 Fourth power storage cell, 321 Bottom wall portion, 322 Front wall portion, 323 Rear wall portion, 324, 325 Side wall portion, H Hollow portion, S1, S2 Projection area, T1, T2 Thickness.

Claims

1. a first storage cell and a second storage cell arranged side by side at an interval in a first direction; a case that accommodates the first storage cell and the second storage cell; a cross member extending along a second direction perpendicular to the first direction and the vertical direction and disposed between the first storage cell and the second storage cell, The case includes a pair of side walls extending along the first direction and arranged side by side in the second direction, the cross member is connected to each of the pair of side walls at both ends in the second direction, The cross member has a hollow portion in a cross section perpendicular to the second direction, the cross member has a first wall portion facing the first storage cell in the first direction and a partition wall that intersects with the first direction in the cross section and divides the hollow portion, The partition wall has a thickness equal to or smaller than a thickness of the first wall portion.

2. The power storage device according to claim 1 , wherein a projected area of ​​the partition wall in the first direction is equal to or greater than 25% and equal to or less than 100% of a projected area of ​​the first wall portion in the first direction.

3. The power storage device according to claim 1 , wherein a smaller angle of an intersection between the first direction and the partition wall is equal to or greater than 45 degrees and less than 90 degrees, or the intersection angle is 90 degrees.

4. The first storage cell has a first exhaust valve, The power storage device according to claim 1 , wherein the first exhaust valve faces the cross member in the first direction.

5. The second storage cell has a second exhaust valve, The power storage device according to claim 4 , wherein the second exhaust valve faces the cross member in the first direction.

6. The power storage device according to claim 4 , wherein the first exhaust valve is disposed so as to overlap the partition wall when viewed from the first direction.

7. The power storage device according to claim 6 , wherein the first wall portion is provided with a first opening portion at a position opposite the first exhaust valve.

8. The power storage device according to claim 7 , wherein the first opening is covered with a breakable heat insulating member.

9. The power storage device according to claim 8 , wherein the heat insulating member has an easily breakable portion.

10. The easily breakable portion is constituted by a break line, The power storage device according to claim 9 , wherein the first exhaust valve is disposed opposite the break line in the first direction.

11. The cross member is provided with a communication portion that communicates the hollow portion with a space surrounding the cross member, The power storage device according to claim 7 , wherein the communication portion is provided at a position not facing the first exhaust valve.

12. A bottom surface defining portion defining a bottom surface of the hollow portion is further provided, The end portion of the partition wall located on the bottom surface defining portion side is a free end, The power storage device according to claim 11 , wherein a gap is provided between the free end and the bottom surface defining portion.

13. The power storage device according to claim 11 , wherein the communication portion is provided above the first exhaust valve in the vertical direction perpendicular to the first direction and the second direction.

14. a height of the cross member in the vertical direction is greater than heights of the first storage cell and the second storage cell in the vertical direction, The power storage device according to claim 13 , wherein the communication portion is provided above the first power storage cell and the second power storage cell.

15. The cross member has an upper wall portion in the vertical direction, The power storage device according to claim 13 , wherein the communication portion is provided in the upper wall portion.

16. The power storage device according to claim 1 , wherein the partition wall has a plurality of wall portions arranged at intervals in the first direction.

17. The power storage device according to claim 1 , wherein at least a part of the partition wall is provided with an area having a reflectance higher than that of the first wall portion.

18. a third storage cell disposed on an opposite side to a side on which the second storage cell is located with respect to the first storage cell in the first direction; 4. The energy storage device according to claim 1, further comprising: a cooler disposed in a gap between the first energy storage cell and the third energy storage cell, the cooler cooling the first energy storage cell and the third energy storage cell.

Images