Electricity storage device

Abstract

A power storage device is provided with at least one power storage unit, a bottom wall, a panel member provided below the bottom wall, and a protective member provided on the bottom wall. A safety valve is provided on the lower surface of the power storage unit. The bottom wall has a through hole provided at a position facing the relief valve. The protective member includes a heat insulating member disposed within the through hole. The heat insulation member includes a receiving surface located below an upper surface of the bottom wall.

Description

Technical Field

[0001] This disclosure relates to energy storage devices. Background Technology

[0002] For example, Japanese Patent Application Publication No. 2024-501935 discloses an electrical device comprising a plurality of battery cells, a first frame housing the plurality of battery cells, a second frame housing the first frame, and an isolation member disposed within the second frame. The isolation member supports the first frame at a position above the bottom surface of the second frame. A collection chamber is formed below the isolation member in the second frame. A third weak region is provided on the lower surface of each battery cell, a pressure relief region is provided on the bottom surface of the first frame, and a second weak region is provided on the isolation member. Excrement discharged from the battery cells through the third weak region flows into the collection chamber formed below the isolation member via the pressure relief region and the second weak region. Summary of the Invention

[0003] In the electrical device described in Japanese Patent Application Publication No. 2024-501935, the discharge from the battery cell through the third weak area requires time to break through the pressure relief area and the second weak area. During this period, a portion of the contents of the battery cell contained in the discharge (so-called fragments) may be scattered into the space between the battery cell and the first frame without passing through the pressure relief area and the second weak area.

[0004] The purpose of this disclosure is to provide an energy storage device that suppresses the dispersion of the contents of the energy storage unit contained in the discharge of the energy storage unit.

[0005] An energy storage device according to one aspect of this disclosure includes: at least one energy storage unit; a bottom wall disposed below the at least one energy storage unit; a panel member disposed below the bottom wall and defining a smoke exhaust path together with the bottom wall; and a protective member disposed on the bottom wall, wherein a safety valve is disposed on the lower surface of the at least one energy storage unit, the bottom wall having a through hole disposed opposite to the safety valve, the protective member including a heat insulation member disposed within the through hole, the heat insulation member including a bearing surface located below the upper surface of the bottom wall.

[0006] According to this disclosure, it is possible to provide an energy storage device that suppresses the dispersion of the contents of the energy storage unit contained in the discharge of the energy storage unit. Attached Figure Description

[0007] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, wherein like reference numerals denote like elements, wherein:

[0008] Figure 1 This is a perspective view schematically illustrating an embodiment of the energy storage device of the present disclosure.

[0009] Figure 2 It is a plan view that roughly shows the state after the top cover of the energy storage device has been removed.

[0010] Figure 3 yes Figure 2 A cross-sectional view at line III-III.

[0011] Figure 4 It is a cross-sectional view that roughly represents a modified example of the protective component.

[0012] Figure 5 It is a cross-sectional view that roughly shows a modified example of the base wall and protective components.

[0013] Figure 6 It is a cross-sectional view that roughly shows a modified example of the base wall and protective components.

[0014] Figure 7 It is a cross-sectional view that roughly represents a modified example of the protective component. Detailed Implementation

[0015] Embodiments of this disclosure will be described with reference to the accompanying drawings. Furthermore, in the drawings referred to below, the same reference numerals are used for the same or equivalent components.

[0016] Figure 1 This is a perspective view schematically illustrating an embodiment of the energy storage device of the present disclosure. Figure 2 It is a plan view that roughly shows the state after the top cover of the energy storage device has been removed. Figure 3 yes Figure 2 A cross-sectional view at line III-III.

[0017] In this embodiment, the energy storage device 10 is mounted, for example, on the lower part of a vehicle. Examples of vehicles include hybrid electric vehicles, plug-in hybrid electric vehicles, and battery electric vehicles.

[0018] like Figures 1 to 3 As shown, the energy storage device 10 includes six energy storage stacks 11-16, a frame 200, a protective component 280, an enclosure component 290, equipment 300, an equipment cooler 350, and refrigerant piping 400. The number of energy storage stacks is not limited to six.

[0019] Each of the energy storage stacks 11-16 is formed as a cuboid elongated along the first direction DR1. For example... Figure 2 As shown, six battery stacks 11-16 are arranged along a second direction DR2, which is orthogonal to both the first direction DR1 and the vertical direction. In this embodiment, the first direction DR1 corresponds to the front-rear direction of the vehicle, and the second direction DR2 corresponds to the left-right direction (width direction) of the vehicle. Each battery stack 11-16 includes at least one battery storage unit 100. In this embodiment, each battery stack 11-16 includes multiple battery storage units 100 and multiple cooling plates 150.

[0020] Multiple energy storage units 100 are arranged in a manner that follows a first direction DR1. For example... Figure 3 As shown, each energy storage unit 100 has an electrode body 112, a unit housing 114, and a pair of external terminals 116.

[0021] The electrode body 112 can be composed of a wound body formed by winding a positive electrode sheet and a negative electrode sheet with a separator between them, or it can be composed of a laminated body formed by stacking a positive electrode sheet and a negative electrode sheet with a separator between them. The electrode body 112 is formed into a shape that is elongated in the second direction DR2.

[0022] The unit housing 114 houses the electrode body 112. The unit housing 114 is formed in a cuboid shape. The unit housing 114 is made of a metal such as aluminum. A safety valve SV is provided on the lower surface of the unit housing 114.

[0023] A pair of external terminals 116 are disposed on the outer surface of the unit housing 114. In this embodiment, the pair of external terminals 116 are disposed on the upper surface of the unit housing 114. The pair of external terminals 116 are disposed at positions that are separated from each other in the width direction of the unit housing 114. In addition, the width direction of the unit housing 114 corresponds to the second direction DR2.

[0024] like Figure 3 As shown, each cooling plate 150 is disposed between a pair of adjacent energy storage units 100 in the first direction DR1. Each cooling plate 150 is formed as a long flat plate in the second direction DR2. Each cooling plate 150 has a flow path for refrigerant to flow along the second direction DR2 (not shown).

[0025] The 200-cell housing accommodates six battery packs, numbers 11-16. Figures 1 to 3 As shown, the frame 200 has a lower shell 210, an upper cover 220, and a panel member 230.

[0026] The lower housing 210 has an opening at the top. The lower housing 210 may be formed of a metal such as aluminum. The lower housing 210 has a bottom wall 212, a peripheral wall 214, and a pair of partition walls 216.

[0027] The bottom wall 212 is located below each of the battery stacks 11-16. In this embodiment, the bottom wall 212 is formed as a solid, flat plate. However, the bottom wall 212 can also be formed as a hollow plate. The bottom wall 212 can be formed by extrusion molding. Figure 3 As shown, multiple through holes h are formed in the bottom wall 212. Each through hole h is positioned opposite to the safety valve SV. The length of each through hole h in the first direction DR1 is greater than the length of the safety valve SV in the first direction DR1.

[0028] The protective component 280 is mounted on the bottom wall 212. For example... Figure 3 As shown, the protective member 280 has multiple heat insulation members 282 and retaining plates 284.

[0029] Each heat insulation member 282 is disposed within the through hole h. Each heat insulation member 282 includes a bearing surface 282s located below the upper surface 212s of the bottom wall 212. Each heat insulation member 282 has a shape that closes the through hole h. In this embodiment, the lower surface of each heat insulation member 282 is set to be coplanar with the lower surface of the bottom wall 212. Each heat insulation member 282 has the function of protecting each energy storage unit 100 from the gas discharged from the safety valve SV. Each heat insulation member 282 is, for example, made of mica, which is solidified from natural inorganic minerals by hot pressing.

[0030] The retaining sheet 284 holds a plurality of insulating members 282. The retaining sheet 284 is made of, for example, polypropylene. The retaining sheet 284 includes an adhesive portion 285, which is bonded to the bearing surface 282s at a position lower than the upper surface 212s of the bottom wall 212. The back side of the retaining sheet 284 can be bonded to the inner peripheral surface surrounding the through hole h in the bottom wall 212.

[0031] A surrounding member 290 is disposed between the lower surface of the energy storage unit 100 and the upper surface 212s of the bottom wall 212. The surrounding member 290 has a shape that surrounds the through hole h. In this embodiment, the surrounding member 290 is disposed between the bottom surface of the unit housing 114 and the retaining piece 284. The lower surface of the surrounding member 290 is in contact with the retaining piece 284 located on the upper surface 212s of the bottom wall 212. The upper surface of the surrounding member 290 may be in contact with the bottom surface of the unit housing 114. The surrounding member 290 is made of resin, metal, or the like. In addition, the surrounding member 290 may be in contact with the lower surface of the cooling plate 150.

[0032] The peripheral wall 214 rises from the periphery of the bottom wall 212. The peripheral wall 214 has a shape that surrounds each of the battery packs 11 to 16. The peripheral wall 214 may be hollow. The peripheral wall 214 has a front wall 214a and a pair of side walls 214b.

[0033] The front wall 214a is formed on one side of each of the energy storage stacks 11 to 16 in the first direction DR1. Figure 2 (Left side of the vehicle). The front wall 214a extends in the second direction DR2. In addition, in this embodiment, one side in the first direction DR1 corresponds to the front side in the longitudinal direction of the vehicle.

[0034] A pair of sidewalls 214b are spaced apart from each other in the second direction DR2. Each sidewall 214b extends in the first direction DR1. One end (front end) of each sidewall 214b in the first direction DR1 is connected to the front wall 214a.

[0035] A pair of partition walls 216 divides the space surrounded by the bottom wall 212 and the peripheral wall 214 into a space where each of the battery stacks 11-16 is arranged and other spaces. The pair of partition walls 216 are arranged to be separated from each other in a first direction DR1. Each partition wall 216 extends in a second direction DR2. Each partition wall 216 may be hollow. The pair of partition walls 216 have the function of constraining each of the battery stacks 11-16 from both sides in the first direction DR1. Figure 2 As shown, the end of the partition wall 216 formed on one side (front side) of the first direction DR1 on the second direction DR2 is separated from each side wall 214b. The end of the partition wall 216 formed on the other side (rear side) of the first direction DR1 on the second direction DR2 is connected to each side wall 214b.

[0036] The upper cover 220 is positioned above each of the battery stacks 11 to 16. The upper cover 220, together with the lower housing 210, houses the six battery stacks 11 to 16. Specifically, the upper cover 220 and the lower housing 210 house the six battery stacks 11 to 16 in a sealed manner. The periphery of the upper cover 220 is connected to the upper end of the peripheral wall 214 via bolts or the like through a sealing member.

[0037] The panel member 230 is disposed below the lower housing 210. The panel member 230 functions to protect the bottom wall 212 of the lower housing 210. The panel member 230 may also be formed in the shape of a flat plate. The periphery of the panel member 230 is connected to the lower surface of the lower housing 210 through a sealing member.

[0038] like Figure 3 As shown, a space S is formed between the panel member 230 and the bottom wall 212. The space S functions as a smoke exhaust path (hereinafter referred to as "smoke exhaust path S"). The smoke exhaust path S is a path for discharging the gas discharged from the safety valve SV of the energy storage unit 100 to the outside of the frame 200.

[0039] like Figure 2 and Figure 3As shown, a smoke exhaust duct section 218 is formed on the peripheral wall 214. The smoke exhaust duct section 218 extends upward from the bottom wall 212. The smoke exhaust duct section 218 guides gas upward from the smoke exhaust path S. An explosion-proof valve EV is provided at the downstream end of the smoke exhaust duct section 218. The explosion-proof valve EV releases the pressure inside the frame 200. The explosion-proof valve EV opens when the pressure inside the frame 200 reaches a reference value or higher. The explosion-proof valve EV is composed of a check valve. Figure 3 As shown, when gas is discharged from any of the energy storage units 100, the gas diffuses in the first direction DR1 through the smoke exhaust path S and is discharged outside the frame 200 through the smoke exhaust pipe section 218 and the explosion-proof valve EV.

[0040] Equipment type 300 is housed in enclosure 200. For example... Figure 2 As shown, device type 300 is disposed on the other side of the lower housing 210 formed in the first direction DR1, that is, in the space between the partition wall 216 and the peripheral wall 214 on the other side (rear side) of the first direction DR1. Device type 300 may include a junction box. Device type 300 may include relays, control devices, etc.

[0041] Equipment cooler 350 cools equipment 300. For example... Figure 2 and Figure 3 As shown, the equipment cooler 350 is disposed between the bottom wall 212 and the equipment 300. A thermally conductive adhesive 900 may be disposed between the equipment cooler 350 and the bottom wall 212.

[0042] Refrigerant piping 400 is arranged within the frame 200. Refrigerant piping 400 is connected to each cooling plate 150 and the equipment cooler 350. For example... Figure 1 and Figure 2 As shown, an inflow port 181 and an outflow port 182 are provided on the front wall 214a of the peripheral wall 214. A refrigerant piping 400 is connected to the inflow port 181 and the outflow port 182. Therefore, refrigerant (water, oil, etc.) supplied from the inflow port 181 flows through the refrigerant piping 400 into each cooling plate 150 and the equipment cooler 350, and after cooling each energy storage unit 100 and the equipment 300, flows out through the refrigerant piping 400 from the outflow port 182.

[0043] like Figure 2 As shown, the refrigerant piping 400 has an upstream piping 410 and a downstream piping 420.

[0044] The upstream end of the upstream piping 410 is connected to the inflow port 181. The downstream end of the upstream piping 410 is connected to one end of the equipment cooler 350 on the second direction DR2. The upstream piping 410 is arranged between the front wall 214a and the partition wall 216 formed on one side of the first direction DR1, and between the side wall 214b and the energy storage stack 11 disposed on one side of the second direction DR2. The upstream piping 410 is connected to one end of each cooling plate 150 on the second direction DR2.

[0045] The upstream end of the downstream piping 420 is connected to the other end of the equipment cooler 350 on the second direction DR2. The downstream end of the downstream piping 420 is connected to the outlet port 182. The downstream piping 420 is arranged between the front wall 214a and the partition wall 216 formed on one side of the first direction DR1, and between the side wall 214b and the energy storage stack 16 arranged on the other side of the second direction DR2. The downstream piping 420 is connected to the other end of each cooling plate 150 on the second direction DR2.

[0046] In the energy storage device 10 described above, when discharge material is discharged downwards from the safety valve SV in any of the energy storage units 100 due to a short circuit or the like, the discharge material flows into the through hole h and collides with the adhesive portion 285 and the bearing surface 282s. Then, due to the melting of the adhesive portion 285 and the cracking of the heat insulation member 282, the discharge material containing the contents of the energy storage unit 100 (so-called fragments) flows into the smoke exhaust path S. Then, the gas contained in the discharge material diffuses in the smoke exhaust path S and... Figure 3 As shown, the contents are discharged from the frame 200 through the explosion-proof valve EV.

[0047] The following describes variations of the above-described embodiments.

[0048] First variation

[0049] like Figure 4 As shown, the bearing surface 282s of the heat insulation member 282 can be formed into a concave shape, which gradually moves downward toward the center of the first direction DR1.

[0050] Second variation

[0051] like Figure 5 As shown, the through hole h may have a reduced diameter portion h1 and a retaining portion h2. The diameter of the reduced diameter portion h1 gradually decreases downward from the upper surface 212s of the bottom wall 212. The retaining portion h2 extends downward from the lower end of the reduced diameter portion h1 and retains the heat insulation member 282.

[0052] In this method, the contents of the energy storage unit 100 flow more reliably into the through hole h.

[0053] Third variation

[0054] like Figure 6 As shown, the bottom wall 212 may include a support portion 212b. The support portion 212b protrudes inward from the lower end of the inner peripheral surface surrounding the through hole h in the bottom wall 212. The support portion 212b supports the thermal insulation member 282.

[0055] Fourth variation

[0056] like Figure 7 As shown, the retaining piece 284 can be fixed to the lower surface of the bottom wall 212 by adhesive or the like. In this example, the thermal insulation member 282 is supported from below by the retaining piece 284.

[0057] Fifth variation

[0058] Although not shown in the figure, a pair of external terminals 116 may be provided on the lower surface of the battery housing 114. In this case, a busbar (not shown) connecting the external terminals 116 of a pair of adjacent energy storage units 100 to each other is arranged between the energy storage unit 100 and the bottom wall 212. In this case, a surrounding member 290 is provided inside the pair of external terminals 116 and the busbar.

[0059] In this method, the discharge from the safety valve SV is suppressed from adhering to the external terminal 116 and the busbar.

[0060] Those skilled in the art should understand that the above exemplary embodiments are specific examples of the following methods.

[0061] Method 1

[0062] An energy storage device, comprising:

[0063] At least one energy storage unit;

[0064] The bottom wall is disposed below the at least one energy storage unit;

[0065] A panel component, disposed below the bottom wall, defines the smoke exhaust path together with the bottom wall; and

[0066] Protective components are provided on the bottom wall.

[0067] A safety valve is provided on the lower surface of the at least one energy storage unit.

[0068] The bottom wall has a through hole located opposite the safety valve.

[0069] The protective component includes a heat insulation component disposed within the through hole.

[0070] The thermal insulation member includes a bearing surface located below the upper surface of the bottom wall.

[0071] In this energy storage device, the heat-insulating member disposed within the through-hole has a bearing surface located below the upper surface of the bottom wall, thus allowing the contents of the energy storage unit contained in the discharge of the energy storage unit to effectively flow into the through-hole. This suppresses the scattering of the contents of the energy storage unit.

[0072] Method 2

[0073] According to the energy storage device of method 1, the protective member further includes a retaining piece for holding the heat insulation member.

[0074] The retaining sheet includes an adhesive portion that is bonded to the bearing surface at a position below the upper surface of the bottom wall.

[0075] In this method, the scattering of the contents of the energy storage unit is suppressed, and the detachment of the heat insulation component from the through hole is also suppressed.

[0076] Method 3

[0077] According to the energy storage device of method 1 or 2, the through hole includes:

[0078] The diameter-reducing portion gradually decreases in diameter downwards from the upper surface of the bottom wall; and

[0079] The retaining part extends downward from the lower end of the reduced diameter part to retain the heat insulation member.

[0080] In this method, the contents of the energy storage unit flow more reliably into the through hole.

[0081] Method 4

[0082] According to any one of the embodiments 1 to 3, the energy storage device further comprises a surrounding member disposed between the at least one energy storage unit and the bottom wall, having a shape that surrounds the through hole.

[0083] In this embodiment, the contents of the energy storage unit flow more reliably into the through hole.

[0084] Furthermore, the embodiments disclosed herein should be considered illustrative rather than restrictive in all respects. The scope of this disclosure is defined by the claims rather than the description of the above embodiments, and includes all modifications within the scope of the claims.

Claims

1. An energy storage device, wherein, have: At least one energy storage unit; The bottom wall is disposed below the at least one energy storage unit; A panel component is disposed below the bottom wall and, together with the bottom wall, defines the smoke exhaust path; as well as Protective components are provided on the bottom wall. A safety valve is provided on the lower surface of the at least one energy storage unit. The bottom wall has a through hole, which is located opposite to the safety valve. The protective component includes a heat insulation component disposed within the through hole. The thermal insulation component includes a bearing surface located below the upper surface of the bottom wall.

2. The energy storage device according to claim 1, wherein, The protective component also includes a retaining piece to hold the heat insulation component in place. The retaining sheet includes an adhesive portion that is bonded to the bearing surface at a position below the upper surface of the bottom wall.

3. The energy storage device according to claim 1, wherein, The through hole includes: The diameter-reducing portion gradually decreases in diameter downwards from the upper surface of the bottom wall; and The retaining part extends downward from the lower end of the reduced diameter part to retain the heat insulation member.

4. The energy storage device according to any one of claims 1 to 3, wherein, The energy storage device also includes a surrounding member disposed between the at least one energy storage unit and the bottom wall, having a shape that surrounds the through hole.

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