Power storage device

Abstract

To easily discharge gas generated inside a case to the outside of the case.SOLUTION: A power storage device 1 includes a power storage module 20, an adhesive 60 formed on the upper surface of the power storage module 20, a cooling plate 70 arranged on the upper surface of the adhesive 60, a case 30 that houses the power storage module 20, the adhesive 60, and the cooling plate 70, and a case smoke vent valve 40 provided in the case 30. When the case smoke vent valve 40 and the cooling plate 70 are viewed in plan, the case smoke vent valve 40 is arranged at a position away from the cooling plate 70.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] For example, Japanese Patent Application Laid-Open Publication No. 2021-111520 (Patent Document 1) discloses a battery pack (power storage device) including a plurality of battery cells (power storage cells), a battery pack case (case), a tray, and a cooler (cooling plate). In the battery pack disclosed in Japanese Patent Application Laid-Open Publication No. 2021-111520, a tray is disposed above the plurality of battery cells, and a cooler is disposed above the tray. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-111520 Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, the case is provided with a case smoke exhaust valve that exhausts gas generated inside the case. Depending on the location of the case smoke exhaust valve, it is possible that the cooler may prevent the gas generated inside the case from being exhausted to the outside of the case.

[0005] An object of the present disclosure is to provide an electricity storage device that can easily discharge gas generated inside the case to the outside of the case. [Means for solving the problem]

[0006] An energy storage device according to an aspect of the present disclosure includes an energy storage module, an adhesive formed on an upper surface of the energy storage module, a cooling plate disposed on the upper surface of the adhesive, a case that houses the energy storage module, the adhesive, and the cooling plate, and a case smoke vent valve provided in the case. When the case smoke vent and the cooling plate are viewed in plan, the case smoke vent valve is located at a position separated from the cooling plate.

[0007] Preferably, the energy storage device further includes a first junction box arranged at a distance from the energy storage module in a first direction. If a direction intersecting both the first direction and the up-and-down direction is defined as a second direction, the energy storage device further includes a second junction box arranged at a distance from the energy storage module in the first direction and arranged adjacent to the first junction box in the second direction. The case includes an upper cover and a lower case. A space is formed in the energy storage device in which the first junction box and the second junction box are arranged. The case smoke exhaust valve is provided in the upper cover above the space.

[0008] Preferably, the space includes an inter-box area located between the first junction box and the second junction box, and the case smoke exhaust valve is provided above the inter-box area. [Effects of the Invention]

[0009] According to the present disclosure, gas generated inside the case can be easily discharged to the outside of the case. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a side view schematically illustrating a vehicle including an electricity storage device according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is an exploded perspective view of the electricity storage device shown in FIG. [Figure 3] FIG. 3 is a perspective view schematically showing the storage cell shown in FIG. 2. [Figure 4]FIG. 3 is a plan view schematically showing the power storage device shown in FIG. 2. [Figure 5] 3 is a plan view schematically showing a state in which an upper cover is removed from the power storage device shown in FIG. 2.

[0023] FIG. [Figure 6] FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. [Figure 7] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments and modifications according to the present disclosure will be described with reference to the drawings. In the following description, the same parts and components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions thereof will not be repeated. Note that the embodiments and modifications described below may be selectively combined as appropriate.

[0012] [Embodiment] An electricity storage device according to an embodiment of the present disclosure will be described with reference to Figs. 1 to 7. Fig. 1 is a side view schematically showing a vehicle including an electricity storage device according to an embodiment of the present disclosure. Fig. 2 is an exploded perspective view of the electricity storage device shown in Fig. 1. Fig. 3 is a perspective view schematically showing an electricity storage cell shown in Fig. 2. Fig. 4 is a plan view schematically showing the electricity storage device shown in Fig. 2 with an upper cover removed. Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 4. Fig. 7 is a cross-sectional view taken along line VII-VII in Fig. 4.

[0013] 1, a vehicle 10 includes a power storage device 1, a vehicle frame 3, and a floor panel 4. The power storage device 1 is disposed below the floor panel 4. Examples of the vehicle 10 include a hybrid vehicle, a plug-in hybrid vehicle, a fuel cell vehicle, and an electric vehicle.

[0014] Referring to Figure 2, the energy storage device 1 includes an energy storage module 20, a case 30, a case smoke exhaust valve 40, a first junction box 51, a second junction box 52, an adhesive 60, a cooling plate 70, a main bus bar 81, a sub-bus bar 82 (see Figure 5), and an inter-cell bus bar 217 (see Figure 5).

[0015] The energy storage module 20 includes a plurality of energy storage cells 211. The plurality of energy storage cells 211 are arranged to line up in a first direction. In this embodiment, the first direction corresponds to the front-rear direction of the vehicle 10 (see FIG. 1 ). However, the first direction does not have to be the front-rear direction of the vehicle 10. The first direction may be a direction that intersects both the front-rear direction of the vehicle 10 and the up-down direction of the energy storage device 1. For example, the first direction may be the width direction of the vehicle 10.

[0016] In this embodiment, the plurality of storage cells 211 includes 16 storage cells 211. However, the number of storage cells 211 is not limited to 16. The number of storage cells 211 may be one or more. An example of each storage cell 211 is a lithium ion battery. Each storage cell 211 may be an all-solid-state battery using a solid electrolyte.

[0017] 3, the energy storage cell 211 is formed in a rectangular parallelepiped shape that is long in a direction perpendicular to both the first direction and the vertical direction of the energy storage device 1. In the following description, the direction perpendicular to both the first direction and the vertical direction of the energy storage device 1 is also referred to as the "orthogonal direction."

[0018] The energy storage cell 211 includes an upper surface 21, a lower surface 22, a pair of short side surfaces 23, 24, and a pair of long side surfaces 25, 26. The pair of short side surfaces 23, 24 are spaced apart in the orthogonal direction. The pair of long side surfaces 25, 26 are spaced apart in the first direction. Each of the pair of long side surfaces 25, 26 is formed to extend in the orthogonal direction.

[0019] The energy storage cell 211 includes a positive electrode terminal 213 and a negative electrode terminal 212. The positive electrode terminal 213 is provided on one of the pair of short side surfaces 23, 24, and the negative electrode terminal 212 is provided on the other of the pair of short side surfaces 23, 24. In the example shown in FIG. 3 , the positive electrode terminal 213 is provided on the short side surface 24, and the negative electrode terminal 212 is provided on the short side surface 23.

[0020] The electric storage cell 211 further includes a cell smoke vent valve 218 that vents gas inside the electric storage cell 211. When the internal pressure of the electric storage cell 211 increases, the cell smoke vent valve 218 vents the gas inside the electric storage cell 211 to the outside of the electric storage cell 211. The cell smoke vent valve 218 is provided on the short side surface 23 on which the negative electrode terminal 212 is provided.

[0021] The arrangement of the multiple energy storage cells 211 in the case 30 (see FIG. 2) will be described with reference to FIGS. 5 and 6. In FIG. 5, components that are hidden by the cooling plate 70 when the energy storage device 1 is viewed from above with the upper cover 31 (see FIG. 2) removed are indicated by dotted lines. Also, in FIG. 5, the adhesive 60 is not shown. In FIG. 6, the main bus bar 81 and the sub-bus bar 82 shown in FIG. 5 are not shown. As shown in FIGS. 5 and 6, the multiple energy storage cells 211 are arranged in the case 30 such that the positive electrode terminals 213 and the negative electrode terminals 212 are alternately arranged along the first direction. The inter-cell bus bar 217 is a conductor bar capable of passing a large amount of current. The inter-cell bus bar 217 is made of, for example, copper. Adjacent positive electrode terminals 213 and negative electrode terminals 212 are electrically connected by the inter-cell bus bar 217. As a result, the multiple energy storage cells 211 in the case 30 (see FIG. 2) are electrically connected in series.

[0022] 2, the case 30 houses the power storage module 20, a first junction box 51, a second junction box 52, an adhesive 60, a cooling plate 70, a main bus bar 81, a sub-bus bar 82 (see FIG. 5), and an inter-cell bus bar 217 (see FIG. 5). The case 30 has a lower case 32 and an upper cover 31. The case 30 is provided with a case smoke exhaust valve 40.

[0023] The lower case 32 is open upward. The lower case 32 has a bottom wall 321 and a peripheral wall 322. The peripheral wall 322 stands upright from the peripheral edge of the bottom wall 321. The peripheral wall 322 is formed in a substantially rectangular tubular shape. The peripheral wall 322 includes a side wall 323, a side wall 324, a side wall 325, and a side wall 326. The side walls 325 and 326 are spaced apart in the first direction. The side walls 323 and 324 are spaced apart in an orthogonal direction that is orthogonal to both the first direction and the vertical direction of the energy storage device 1. The side walls 325 and 326 are connected by the side walls 323 and 324.

[0024] The upper cover 31, together with the lower case 32, houses the power storage module 20, the first junction box 51, the second junction box 52, the adhesive 60, the cooling plate 70, the main bus bar 81, the sub-bus bar 82 (see FIG. 5), and the inter-cell bus bar 217 (see FIG. 5). The peripheral edge of the upper cover 31 is fixed to the upper end of the peripheral wall 322 with bolts or the like.

[0025] 5, in the energy storage device 1, a space S1 is formed between the energy storage module 20 and the side wall 325. In addition, in the energy storage device 1, a space S2 is formed between the energy storage module 20 and the side wall 323. In addition, in the energy storage device 1, a space S3 is formed between the energy storage module 20 and the side wall 324.

[0026] The first junction box 51 and the second junction box 52 are disposed in the space S1. More specifically, the first junction box 51 is disposed at a distance from the power storage module 20 in the first direction. The first junction box 51 houses a positive relay. The first junction box 51 is provided with a positive bus bar connection terminal 91 and a positive external terminal 93 (see FIG. 2). The positive bus bar connection terminal 91 and the positive external terminal 93 are connected via a positive relay inside the first junction box 51. The first junction box 51 may further house a fuse.

[0027] The second junction box 52 is disposed at a distance from the power storage module 20 in the first direction. The second junction box 52 is disposed adjacent to the first junction box 51 in the second direction. The second direction intersects with both the first direction and the vertical direction of the power storage device 1. In the present embodiment, the second direction is perpendicular to both the first direction and the vertical direction of the power storage device 1. That is, in the present embodiment, the second direction coincides with the orthogonal direction. However, the second direction is not limited to being perpendicular. The second direction may intersect with both the first direction and the vertical direction of the power storage device 1. The second junction box 52 houses a negative relay. The second junction box 52 is provided with a negative bus bar connection terminal 92 and a negative external terminal 94 (see FIG. 2 ). The negative bus bar connection terminal 92 and the negative external terminal 94 are connected via a negative relay inside the second junction box 52. The second junction box 52 may further house a fuse.

[0028] The main bus bar 81 and the sub-bus bar 82 are conductor bars capable of passing a large amount of current. The main bus bar 81 and the sub-bus bar 82 are made of a material such as copper. A connector 83 at one end of the main bus bar 81 is connected to a bus bar connection terminal 91. The other end of the main bus bar 81 is connected to a positive terminal 213 of the power storage cell 211a. The power storage cell 211a is the power storage cell that is arranged outermost in the first direction among the multiple power storage cells 211. In other words, the power storage cell 211a is the power storage cell that is arranged at a position farthest from the first junction box 51 and the second junction box 52 among the multiple power storage cells 211.

[0029] A connector 84 at one end of the sub-bus bar 82 is connected to a bus bar connection terminal 92. The other end of the sub-bus bar 82 is connected to a negative terminal 212 of the power storage cell 211b. The power storage cell 211b is the power storage cell that is arranged on the innermost side in the first direction among the multiple power storage cells 211. In other words, the power storage cell 211b is the power storage cell that is arranged in a position closest to the first junction box 51 and the second junction box 52 among the multiple power storage cells 211. Except for the connection portions, the main bus bar 81 and the sub-bus bar 82 are covered with an insulator such as resin.

[0030] 6, adhesive material 60 fixes power storage module 20 and cooling plate 70. Adhesive material 60 is formed on upper surface 251 of power storage module 20. Adhesive material 60 has thermal conductivity.

[0031] The cooling plate 70 is a device that adjusts the temperature of the energy storage cells 211 by cooling the energy storage cells 211. The cooling plate 70 is disposed on an upper surface 65 of the adhesive material 60. As shown in FIGS. 2 and 5 , the cooling plate 70 is formed in a substantially flat plate shape. The cooling plate 70 is fixed to the energy storage module 20 with the adhesive material 60.

[0032] 2, the case smoke exhaust valve 40 exhausts gas inside the case 30 to the outside of the case 30 when the internal pressure of the case 30 exceeds a predetermined pressure. The case smoke exhaust valve 40 is provided on the upper cover 31.

[0033] The position of the case smoke vent valve 40 will be described in more detail with reference to Figures 4 to 7. In Figure 4, components that are visible when the upper cover 31 is removed from the energy storage device 1 are indicated by dotted lines. As shown in Figure 4, when the case smoke vent valve 40 and the cooling plate 70 are viewed in plan, the case smoke vent valve 40 is located at a position away from the cooling plate 70. With reference to Figure 5, the energy storage device 1 is formed with a space S1 in which the first junction box 51 and the second junction box 52 are located. With reference to Figure 7, the case smoke vent valve 40 is provided in the upper cover 31 above the space S1.

[0034] 5, the space S1 includes an inter-box region R1 located between the first junction box 51 and the second junction box 52. Referring to Fig. 7, the case smoke exhaust valve 40 is provided in the upper cover 31 above the inter-box region R1.

[0035] Referring to Fig. 5, gas discharged from the cell smoke vent valve 218 facing space S2 passes through space S2 and is discharged into space S1. Gas discharged from the cell smoke vent valve 218 facing space S3 passes through space S3 and is discharged into space S1. Referring to Fig. 7, gas discharged into space S1 is discharged to the outside of the case 30 from the case smoke vent valve 40 provided on the upper cover 31 above space S1.

[0036] 6, in the energy storage device 1, a space S4 is formed between the cooling plate 70 and the upper cover 31. Although not shown in FIG. 6, the main bus bar 81 shown in FIG. 5 passes through the space S4. The height of the first junction box 51 is lower than that of the energy storage cells 211. The height of the second junction box 52 (see FIG. 7) is lower than that of the energy storage cells 211. The height is the length in the up-down direction of the energy storage device 1 (see FIG. 2). The cooling plate 70 is disposed on an upper surface 65 of an adhesive 60 formed on an upper surface 251 of the energy storage module 20 including the plurality of energy storage cells 211. Therefore, the distance between the upper cover 31 and the first junction box 51 is longer than the distance between the upper cover 31 and the cooling plate 70. The distance between the upper cover 31 and the second junction box 52 is longer than the distance between the upper cover 31 and the cooling plate 70. In other words, a fairly large space is formed below the case smoke vent valve 40. Therefore, gas discharged from each of the energy storage cells 211 tends to collect below the case smoke exhaust valve 40. Therefore, in this embodiment, gas generated inside the case 30 can be easily discharged to the outside of the case 30.

[0037] It should be noted that the case smoke exhaust valve 40 only needs to be provided on the upper cover 31 above the space S1, and the case smoke exhaust valve 40 does not have to be located above the inter-box region R1 (see FIG. 7).

[0038] As described above, in the present embodiment, when the case smoke vent valve 40 and the cooling plate 70 are viewed in plan, the case smoke vent valve 40 is disposed at a position distant from the cooling plate 70. If the case smoke vent valve 40 were provided on the upper cover 31 above the cooling plate 70, the upper cover 31 and the cooling plate 70 would be close to each other, and gas discharged from each energy storage cell 211 would not easily collect below the case smoke vent valve 40. In other words, if the case smoke vent valve 40 were provided on the upper cover 31 above the cooling plate 70, the cooling plate 70 would prevent gas generated within the case 30 from being discharged to the outside of the case 30. However, in the present embodiment, when the case smoke vent valve 40 and the cooling plate 70 are viewed in plan, the case smoke vent valve 40 is disposed at a position distant from the cooling plate 70. Therefore, according to the energy storage device 1 of the present embodiment, gas generated within the case 30 can be easily discharged to the outside of the case 30.

[0039] Furthermore, in this embodiment, the case smoke vent valve 40 is provided on the upper cover 31 above the space S1 in which the first junction box 51 and the second junction box 52 are arranged. This creates a fairly large space below the case smoke vent valve 40. Therefore, gas discharged from each energy storage cell 211 tends to collect below the case smoke vent valve 40. Therefore, according to the energy storage device 1 of this embodiment, gas generated inside the case 30 can be easily discharged to the outside of the case 30.

[0040] Furthermore, in this embodiment, the case smoke vent valve 40 is provided on the upper cover 31 above the inter-box region R1 located between the first junction box 51 and the second junction box 52. This leaves a fairly large space below the case smoke vent valve 40. Therefore, gas discharged from each energy storage cell 211 tends to collect below the case smoke vent valve 40. Therefore, according to the energy storage device 1 of this embodiment, gas generated inside the case 30 can be easily discharged to the outside of the case 30.

[0041] [Variations] In the above embodiment, the energy storage device 1 includes the first junction box 51 and the second junction box 52. However, the energy storage device 1 may include a single junction box that includes the functions of the first junction box 51 and the second junction box 52. In this case, too, when the case smoke vent valve 40 and the cooling plate 70 are viewed from above, the case smoke vent valve 40 is disposed at a position away from the cooling plate 70. More specifically, the single junction box is disposed in the space S1, and the case smoke vent valve 40 is provided on the upper cover 31 above the space S1.

[0042] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0043] 1 Energy storage device, 3 Vehicle frame, 4 Floor panel, 10 Vehicle, 20 Energy storage module, 21, 65, 251 Upper surface, 22 Lower surface, 23, 24 Short side, 25, 26 Long side, 30 Case, 31 Upper cover, 32 Lower case, 40 Case smoke exhaust valve, 51 First junction box, 52 Second junction box, 60 Adhesive, 70 Cooling plate, 81 Main bus bar, 82 Sub-bus bar, 83, 84 Connector, 91, 92 Bus bar connection terminal, 93, 94 External terminal, 211, 211a, 211b Energy storage cell, 212 Negative terminal, 213 Positive terminal, 217 Inter-cell bus bar, 218 Cell smoke exhaust valve, 321 Bottom wall, 322 Peripheral wall, 323, 324, 325, 326 Side walls, R1 interbox area, S1, S2, S3, S4 spaces.

Claims

1. A storage module; an adhesive material formed on an upper surface of the power storage module; a cooling plate disposed on the upper surface of the adhesive; a case that accommodates the power storage module, the adhesive, and the cooling plate; a case smoke exhaust valve provided in the case, The power storage device, wherein, when the case smoke exhaust valve and the cooling plate are viewed in plan, the case smoke exhaust valve is disposed at a position away from the cooling plate.

2. the power storage device further includes a first junction box disposed at a distance from the power storage module in a first direction; If a direction intersecting both the first direction and the vertical direction is defined as a second direction, the power storage device further includes a second junction box that is disposed at a distance from the power storage module in the first direction and that is disposed adjacent to the first junction box in the second direction; The case includes an upper cover and a lower case, a space in which the first junction box and the second junction box are disposed is formed in the power storage device; The power storage device according to claim 1 , wherein the case smoke exhaust valve is provided on the upper cover above the space.

3. the space includes an inter-box region located between the first junction box and the second junction box, The power storage device according to claim 2 , wherein the case smoke exhaust valve is provided above the inter-box region.

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