Power storage device

Abstract

To provide a power storage device which can prevent short-circuiting when gas is generated due to heat generation by power storage cells, while suppressing condensation.SOLUTION: A power storage device includes: a housing case 10 which has an installation region R1 where a plurality of power storage stacks 20 can be installed; the one or more power storage stacks 20 which are disposed in the installation region R1 such that an excess region R2 where the at least one power storage stack can be disposed in the installation region R1 is formed; a cooler 40 which can cool the installation region R1; and a heat insulation member 30 which is disposed inside the housing case 10 so as to prevent the cooling inside the housing case 10 by the cooler 40. The power storage stacks 20 each include a plurality of power storage cells which are each provided with an exhaust part provided to be capable of discharging gas from the inside to the outside. The heat insulation member 30 is installed in the excess region R2. At a portion located above the heat insulation member 30, the housing case 10 has a pressure release valve 60.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] As a conventional power storage device, JP 2022-154741 A (Patent Document 1) discloses a configuration for preventing overcooling of a battery stack (power storage stack), in which an inner cooling fin is provided on the inner surface of the bottom wall and an outer cooling fin is provided on the outer surface of the bottom wall, and a plurality of battery stacks are accommodated in a storage case with an air layer between them, and a blower for cooling the battery stack is also accommodated. The blower is configured to stop when the battery temperature is lower than a threshold value, and this makes it possible to perform air-cooling while preventing the batteries from overcooling when the outside air temperature is low. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-154741 A Summary of the Invention [Problem to be solved by the invention]

[0004] In an electricity storage device that houses multiple electricity storage stacks in a housing case, the number of electricity storage stacks installed in the same housing case may be adjusted depending on the vehicle model or the required driving distance. For example, when reducing the number of electricity storage stacks housed, a space is created in an area where no electricity storage stacks are installed. In such a case, if the entire area where the maximum number of electricity storage stacks are installed is cooled by a cooler, the air inside the housing case that has been warmed by the heat generated by the electricity storage stacks will be cooled in that space, and there is a concern that condensation will occur in the area where no electricity storage stacks are installed.

[0005] Furthermore, if gas is generated when a power storage cell contained in a power storage stack generates heat, and no measures are taken, debris such as metal foreign matter contained in the gas may adhere to the power storage stack, causing a short circuit in the power storage stack.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and an object of the present disclosure is to provide an energy storage device that can suppress condensation while suppressing short circuits when gas is generated due to heat generation in a storage cell. [Means for solving the problem]

[0007] The power storage device according to the present disclosure includes a storage case having an installation area in which a plurality of power storage stacks can be installed, one or more power storage stacks arranged in the installation area so that an excess area in which at least one of the power storage stacks can be arranged is formed in the installation area, a cooler capable of cooling the installation area, and a heat insulating member arranged in the storage case for suppressing cooling of the inside of the storage case by the cooler. The power storage stack includes a plurality of power storage cells, each of which is provided with an exhaust part capable of exhausting gas from the inside to the outside. The heat insulating member is installed in the excess area. The storage case is provided with a pressure release valve in a portion located above the heat insulating member.

[0008] According to the above configuration, by disposing the heat insulating member in the surplus area of ​​the installation area where the power storage stack is not disposed, it is possible to prevent the space part of the installation area where the power storage stack is not disposed from being cooled by the cooler, thereby preventing the air heated by the power storage stack from being cooled in the space part, and thus preventing the occurrence of condensation.

[0009] Furthermore, by providing a pressure relief valve above the insulating member, when gas is generated from the power storage cell, debris such as metallic foreign matter contained in the gas can be collected on the side where the insulating member is located, thereby making it possible to prevent the debris from adhering to the power storage stack and causing a short circuit in the power storage stack.

[0010] In the power storage device according to the present disclosure, the cooler may be disposed below the housing case. The heat insulating member may be provided with an open space portion that opens to face the pressure release valve and an air layer. In this case, the air layer may be provided closer to the cooler than the open space portion.

[0011] According to the above-mentioned configuration, by providing an air layer on the side of the heat insulating member closer to the cooler, the heat insulating performance of the heat insulating member can be further improved. In addition, by providing an open space portion that opens toward the pressure release valve, debris can be collected in the open space portion.

[0012] In the power storage device according to the present disclosure, the power storage stacks and the heat insulating member may be arranged side by side in a first direction in the installation area. The heat insulating member may be located on the furthest side in the first direction.

[0013] According to the above configuration, the debris can be collected on the furthest side in the first direction, which can further prevent the debris from adhering to the power storage stack and causing a short circuit in the power storage stack, compared to a case in which the heat insulating member is disposed midway in the first direction. Effect of the Invention

[0014] According to the present disclosure, it is possible to provide an electricity storage device that can suppress condensation and also suppress short circuits when gas is generated due to heat generation in an electricity storage cell. [Brief description of the drawings]

[0015] [Figure 1] 1 is a cross-sectional view of an electricity storage device according to an embodiment. [Diagram 2] 2 is a plan view of the electricity storage device according to the embodiment with an upper case of the storage case removed; FIG. [Diagram 3]4 is an enlarged cross-sectional view showing the periphery of a heat insulating member in the electricity storage device according to the embodiment; FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the embodiments described below, the same or common parts are denoted by the same reference characters in the drawings, and the description thereof will not be repeated.

[0017] Fig. 1 is a cross-sectional view of an electricity storage device according to an embodiment. Fig. 2 is a plan view of the electricity storage device according to the embodiment with an upper case of a housing case removed. The electricity storage device 1 according to the embodiment will be described with reference to Figs. 1 and 2.

[0018] The electricity storage device 1 is mounted on a hybrid vehicle capable of running using at least one of the power of a motor and an engine, or on an electrically powered vehicle that runs using driving force obtained from electric energy.

[0019] The electricity storage device 1 includes a storage case 10, a plurality of electricity storage stacks 20, a heat insulating member 30, a cooler 40, and electronic equipment 50.

[0020] The storage case 10 accommodates therein a plurality of power storage stacks 20, a heat insulating member 30, and electronic devices 50. The storage case 10 includes an upper case 11 and a lower case 12. The upper case 11 constitutes the upper part of the storage case 10.

[0021] The upper case 11 is provided with a pressure relief valve 60. More specifically, the pressure relief valve 60 is provided above the heat insulating member 30 described below. The pressure relief valve 60 opens when the pressure inside the storage case 10 reaches or exceeds a predetermined pressure, and discharges gas inside the storage case 10 to the outside.

[0022] Upper case 11 has a generally box-like shape that opens downward. Upper case 11 has a ceiling portion 111, a peripheral wall portion 112, and a flange portion 113. Peripheral wall portion 112 is provided so as to extend from the periphery of ceiling portion 111. Flange portion 113 is provided so as to bend outward from the lower end side of peripheral wall portion 112.

[0023] Lower case 12 has a generally foil-shaped shape that opens upward. Lower case 12 has a bottom 121, a peripheral wall 122, and a flange 123. Bottom 121 is provided to face ceiling 111. Peripheral wall 122 is provided to extend upward from the periphery of bottom 121. Flange 123 is provided by bending the upper end side of peripheral wall 122 outward.

[0024] With the lower surface of flange portion 113 and the upper surface of flange portion 123 aligned, flange portion 113 and flange portion 123 are fastened together by a plurality of fastening members, thereby joining upper case 11 and lower case 12 together.

[0025] The storage case 10 has an installation area R1 in which a plurality of power storage stacks 20 can be installed. The installation area R1 is an area in which a maximum number of power storage stacks 20 can be installed. In the present embodiment, a case in which three power storage stacks 20 are arranged in the installation area R1 is illustrated, but for example, the installation area R1 is provided so that a maximum number of four power storage stacks 20 can be installed.

[0026] The number of power storage stacks 20 that can be installed in the installation area R1 is not limited to four, but may be two, three, or five or more.

[0027] The multiple power storage stacks 20 are installed in the installation region R1 such that a surplus region R2 capable of installing at least one power storage stack 20 is formed in the installation region R1. In the present embodiment, the surplus region R2 is configured to be capable of installing one power storage stack 20, but the number of power storage stacks 20 that can be installed in the surplus region R2 may be two or more. A heat insulating member 30, which will be described later, is installed in the surplus region R2.

[0028] The power storage stack 20 includes a plurality of power storage cells 21 arranged side by side in a predetermined arrangement direction. The arrangement direction is, for example, parallel to the width direction of the vehicle when the power storage device 1 is mounted on the vehicle. Each of the plurality of power storage cells 21 is provided with an exhaust unit 22 that is capable of exhausting gas from the inside to the outside.

[0029] The power storage cell 21 is, for example, a secondary battery such as a nickel-metal hydride battery or a lithium-ion battery. The power storage cell 21 has, for example, a rectangular shape. The secondary battery may use a liquid electrolyte or a solid electrolyte.

[0030] The power storage stacks 20 are arranged side by side at intervals in a first direction perpendicular to the arrangement direction. The first direction is, for example, parallel to the front-rear direction of the vehicle in the mounted state.

[0031] The power storage stacks 20 are arranged so as to be in thermal contact with the inner surface of the bottom 121 of the housing case 10. For example, the power storage stacks 20 are fixed to the inner surface of the bottom 121 by a thermally conductive adhesive.

[0032] The multiple electricity storage stacks 20 and the heat insulating members 30 are arranged side by side in the first direction. The heat insulating members 30 are arranged so as to be located on the furthest side in the first direction in the installation region R1. A foamed resin or the like can be used as the heat insulating members 30. The heat insulating members 30 have a substantially rectangular parallelepiped shape. The heat insulating members 30 have substantially the same shape as the electricity storage stacks 20.

[0033] The cooler 40 is provided so as to be able to cool the installation area R1. The cooler 40 is disposed below the storage case 10. The cooler 40 is fixed to the outer surface of the bottom 121 of the storage case 10 by, for example, a thermally conductive adhesive.

[0034] The cooler 40 is provided so that, for example, a coolant flows through it. As the coolant flows, the cooler 40 cools the multiple power storage stacks 20 installed in the installation region R1.

[0035] The electronic device 50 controls the multiple power storage stacks 20. The electronic device 50 is, for example, a cell ECU. The electronic device 50 is located on the opposite side to the side on which the heat insulating member 30 is located in the first direction. In other words, one or more power storage stacks 20 are disposed between the electronic device 50 and the heat insulating member 30.

[0036] FIG. 3 is an enlarged cross-sectional view of the periphery of a heat insulating member in the electricity storage device according to the embodiment.

[0037] The heat insulating member 30 is provided with an open space portion 33 and an air layer 35. The open space portion 33 is opened so as to face the pressure release valve 60. The air layer 35 is provided on the lower side of the open space portion 33, i.e., on the side closer to the cooler 40.

[0038] Here, when the power storage cell 21 included in any of the power storage stacks 20 generates heat due to abnormal operation, gas is exhausted from the exhaust section 22. This increases the pressure inside the storage case 10. When the pressure inside the storage case reaches or exceeds a predetermined pressure, the pressure release valve 60 is opened, and the gas inside the storage case 10 is exhausted to the outside through the pressure release valve 60.

[0039] That is, as shown by arrow AR1 in the figure, the gas exhausted from exhaust section 22 flows toward pressure relief valve 60 located above insulating member 30, and is discharged from pressure relief valve 60 toward storage case 10, as shown by arrow AR2 in the figure.

[0040] The gas exhausted from the exhaust section 22 is at a high temperature and contains debris such as metallic foreign matter. By providing a pressure release valve 60 above the insulating member 30 and directing the gas flow toward the insulating member 30, the debris can be collected on the side where the insulating member 30 is located. This makes it possible to prevent the debris from adhering to the power storage stack 20 and causing a short circuit in the power storage stack.

[0041] At this time, by arranging the heat insulating member 30 on the most one side in the first direction in which the multiple power storage stacks 20 and the heat insulating member 30 are lined up, debris can be collected on the most one side in the first direction (specifically, the side opposite to the side on which the electronic device 50 is arranged). This makes it possible to suppress adhesion of debris to the electronic device 50, and also to suppress the occurrence of a short circuit on the electronic device 50 side. Furthermore, compared to a state in which the heat insulating member 30 is arranged midway in the first direction and the power storage stacks 20 are arranged on both sides of the heat insulating member 30, it is possible to suppress adhesion of the debris to the power storage stack 20.

[0042] In addition, by providing the heat insulating member 30 with an open space portion 33 that opens toward the pressure release valve 60, debris can be collected in the open space portion 33.

[0043] Furthermore, by arranging the heat insulating member 30 in the surplus region R2 of the installation region R1 where the power storage stack 20 is not arranged, it is possible to prevent the space portion located in the surplus region R2 from being cooled by the cooler 40. This makes it possible to prevent the air heated by the power storage stack 20 from being cooled in the space portion, thereby preventing condensation from occurring. Furthermore, by providing the air layer 35 on the side of the heat insulating member 30 closer to the cooler 40, it is possible to improve the heat insulating performance.

[0044] The embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0045] 1 Energy storage device, 10 Storage case, 11 Upper case, 12 Lower case, 20 Energy storage stack, 21 Energy storage cell, 22 Exhaust section, 30 Heat insulating member, 33 Open space section, 35 Air layer, 40 Cooler, 50 Electronic device, 60 Pressure release valve, 111 Ceiling section, 112 Peripheral wall section, 113 Flange section, 121 Bottom section, 122 Peripheral wall section, 123 Flange section, R1 Installation area, R2 Surplus area.

Claims

1. a storage case having an installation area in which a plurality of power storage stacks can be installed; one or more of the power storage stacks arranged in the installation area such that an excess area in which at least one of the power storage stacks can be arranged is formed in the installation area; A cooler capable of cooling the installation area; a heat insulating member disposed in the housing case to suppress cooling of the inside of the housing case by the cooler, the electricity storage stack includes a plurality of electricity storage cells, each of which is provided with an exhaust unit capable of exhausting gas from the inside to the outside; The heat insulating member is installed in the excess area, The storage case is provided with a pressure release valve at a portion located above the heat insulating member.

2. The cooler is disposed below the housing case, The heat insulating member is provided with an open space portion that is open to face the pressure release valve and an air layer, The power storage device according to claim 1 , wherein the air layer is provided closer to the cooler than the open space portion.

3. In the installation area, a plurality of the power storage stacks and the heat insulating members are arranged side by side in a first direction, The power storage device according to claim 1 , wherein the heat insulating member is located on the furthest side in the first direction.

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