Power storage device

Abstract

To provide a power storage device capable of improving adhesiveness of a power storage stack against a lower case through a thermal conductivity component and also securing good electrothermal conductivity.SOLUTION: A power storage device 1 is provided with: a power storage stack 10 including a first cell group 11, a second cell group 12 and an intermediate plate 13; a lower case 21 having a bottom wall part 22; a first heat conduction component 61 placed between the first cell group 11 and the bottom wall part 22; and a second heat conduction component 62 placed between the second cell group 12 and the bottom wall part 22. The lower case 21 includes a pedestal part 25 to support the intermediate plate 13, and the first heat conduction component 61 and the second heat conduction component 62 are provided so as to contact with the pedestal part 25.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to an electric storage device mounted on a vehicle. [Background technology]

[0002] As a conventional energy storage device, JP 2020-053148 A (Patent Document 1) discloses an energy storage device having a configuration in which an energy storage stack and a cooler are arranged in a storage case, the energy storage device comprising a plurality of main cooling surfaces, a cooler having a recess between the plurality of main cooling surfaces, and an energy storage stack, and a gel-like heat-conducting member arranged between the plurality of main cooling surfaces and the energy storage stack. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-053148 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the energy storage device described in Patent Document 1, a recess is provided between the multiple main cooling surfaces, making it difficult to ensure a large area for the heat conduction member, and there is a concern that thermal conductivity may decrease.

[0005] Furthermore, a configuration in which the cooler is located outside the housing case has been considered. In such a case, a thermally conductive member may be used to thermally bond the bottom surface of the power storage stack to the bottom wall of the lower case. When bonding the bottom surface of the power storage stack to the bottom wall via the thermally conductive member, air may remain between the bottom surface of the power storage stack and the bottom wall. In such cases, the adhesion of the power storage stack to the lower case is reduced. Furthermore, if the area of the thermally conductive member is small, thermal conductivity is reduced.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and the purpose of the present disclosure is to provide an energy storage device that can improve the adhesion of the energy storage stack to the lower case via a heat conduction member and ensure good thermoelectric conductivity. [Means for solving the problem]

[0007] An energy storage device according to the present disclosure includes an energy storage stack including a first cell group and a second cell group each including a plurality of energy storage cells, and an intermediate plate disposed between the first cell group and the second cell group; a lower case having a bottom wall portion in which the energy storage stack is disposed; a first thermally conductive member disposed between the first cell group and the bottom wall portion; and a second thermally conductive member disposed between the second cell group and the bottom wall portion. The lower case includes a base portion that protrudes from the bottom wall portion and supports the intermediate plate. The first thermally conductive member and the second thermally conductive member are disposed in contact with the base portion.

[0008] As described above, the intermediate plate is supported by the base, and the first and second thermally conductive members are spread by the power storage stack and the bottom wall of the lower case so that the first and second thermally conductive members contact the base. This allows the first and second thermally conductive members to be spread while allowing air to escape from around the base, which is surrounded by the first and second thermally conductive members, the bottom surface of the power storage stack, and the bottom wall. This ensures a large area for the first and second thermally conductive members. As a result, good thermal conductivity can be maintained while improving adhesion between the power storage stack (first and second cell groups) and the bottom wall of the lower case via the first and second thermally conductive members.

[0009] In the energy storage device according to the present disclosure, the intermediate plate may have, in an arrangement direction in which the first cell group and the second cell group are arranged, a first protruding portion protruding from the base portion toward the first cell group and a second protruding portion protruding from the base portion toward the second cell group. In this case, when viewed from a direction perpendicular to the arrangement direction, the first thermally conductive member may be provided to fill a space between the first protruding portion and the base portion, and the second thermally conductive member may be provided to fill a space between the second protruding portion and the base portion.

[0010] According to the above configuration, the first heat conducting member and the second heat conducting member can be reliably brought into contact with each other up to the end of the first cell group and the end of the second cell group located on the intermediate plate side.

[0011] In the energy storage device based on the present disclosure, the base portion may include a first base portion and a second base portion arranged spaced apart from each other in a direction perpendicular to the arrangement direction in which the first cell group and the second cell group are arranged.

[0012] According to the above configuration, when the first heat conduction member and the second heat conduction member are spread apart, air can be released from around both the first base portion and the second base portion, thereby further improving the adhesion of the storage stack to the lower case.

[0013] The power storage device according to the present disclosure may further include a cooler for cooling the power storage stack. The bottom wall portion may have an inner main surface facing the power storage stack and an outer main surface located on the opposite side to the side on which the power storage stack is located. In this case, it is preferable that the cooler be disposed outside the lower case so as to be in thermal contact with the outer main surface.

[0014] With the above configuration, in a configuration in which the cooler is disposed outside the lower case, the power storage stack can be cooled via the bottom wall portion of the lower case and the first and second heat conductive members.

[0015] The power storage device according to the present disclosure may further include a pressing member that presses the power storage stack toward the bottom wall portion. The power storage stack has one end and the other end in the arrangement direction. In this case, it is preferable that the pressing member has a first pressing portion for pressing the one end toward the bottom wall portion and a second pressing portion for pressing the other end toward the bottom wall portion.

[0016] With the above-described configuration, the power storage stack can be pressed against the bottom wall portion, thereby further improving the adhesion between the power storage stack and the bottom wall portion of the lower case. [Effects of the Invention]

[0017] According to the present disclosure, it is possible to provide an electricity storage device that can improve the adhesion of the electricity storage stack to the lower case via a thermally conductive member and ensure good thermoelectric conductivity. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 2 is an exploded perspective view of the electricity storage device according to the embodiment. [Figure 2] 1 is a cross-sectional view of an electricity storage device according to an embodiment. [Figure 3] 4 is an enlarged partial cross-sectional view showing the periphery of a lower end of an intermediate plate of the electricity storage device according to the embodiment. FIG. [Figure 4] 10 is a schematic view showing an initial state of a step of attaching the power storage stack to the lower case via the first heat conductive member and the second heat conductive member in a manufacturing process of the power storage device according to the embodiment. FIG. [Figure 5] FIG. 3 is a plan view of a first heat conducting member and a second heat conducting member applied to a bottom wall portion. [Figure 6] 10 is a schematic view showing a state midway through a step of attaching the power storage stack to the lower case via a first heat conductive member and a second heat conductive member in a manufacturing process of the power storage device according to the embodiment. FIG. [Figure 7]7 is a diagram schematically showing the movement of air between the bottom surface and the bottom wall portion of the electricity storage stack in the intermediate state shown in FIG. 6. FIG. [Figure 8] 10 is a schematic view illustrating a state after a step of attaching the power storage stack to the lower case via the first heat conductive member and the second heat conductive member in a manufacturing process of the power storage device according to the embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the embodiments described below, the same or common parts are denoted by the same reference numerals in the drawings, and the description thereof will not be repeated.

[0020] Fig. 1 is an exploded perspective view of an electricity storage device according to an embodiment. Fig. 2 is a cross-sectional view of the electricity storage device according to the embodiment, taken along line II-II shown in Fig. 1. For convenience, a share panel 50, which will be described later, is omitted from Fig. 2. A electricity storage device 1 according to an embodiment will be described with reference to Figs. 1 and 2.

[0021] The electricity storage device 1 according to the embodiment is mounted on a hybrid vehicle that can run using the power of at least one of a motor and an engine, or an electrically powered vehicle that runs using driving force obtained from electrical energy.

[0022] As shown in Figures 1 and 2, the energy storage device 1 according to the embodiment includes a plurality of energy storage stacks 10, a housing case 20, a cooler 30, an outer heat conduction layer 40, a shear panel 50, a heat conduction member 60, and a pressing member 80 (see Figure 2).

[0023] Each of the plurality of power storage stacks 10 includes a first cell group 11, a second cell group 12, an intermediate plate 13, and a pair of end plates 16 (see FIG. 2).

[0024] The first cell group 11 and the second cell group 12 each include a plurality of energy storage cells 15 (see FIG. 2) arranged side by side in a predetermined direction (DR1 direction). When the energy storage device 1 is mounted on a vehicle, the DR1 direction is, for example, parallel to the width direction of the vehicle.

[0025] The storage cell 15 is, for example, a secondary battery such as a nickel-metal hydride battery or a lithium-ion battery. The single cell has, for example, a rectangular shape. The secondary battery may use a liquid electrolyte or a solid electrolyte. The storage cell 15 may also be a unit capacitor configured to be able to store electricity.

[0026] The intermediate plate 13 is disposed between the first cell group 11 and the second cell group 12. The intermediate plate 13 is disposed in the center of the electricity storage stack 10 in the DR1 direction. The intermediate plate 13 is made of, for example, an insulating synthetic resin.

[0027] The arrangement direction in which the first cell group 11 and the second cell group 12 are arranged is parallel to the direction in which the plurality of power storage cells 15 are arranged side by side, and is parallel to the DR1 direction.

[0028] The pair of end plates 16 are arranged at both ends of the electricity storage stack 10 in the DR1 direction, and sandwich the first cell group 11, the intermediate plate 13, and the second cell group 12. The pair of end plates 16 are made of a metal material such as aluminum.

[0029] The plurality of power storage stacks 10 are arranged side by side in a direction (DR2 direction) perpendicular to the DR1 direction. When the power storage device 1 is mounted on a vehicle, the DR2 direction is, for example, parallel to the front-rear direction of the vehicle.

[0030] The storage case 20 accommodates a plurality of power storage stacks 10 therein. The storage case 20 includes a lower case 21 and an upper case 26.

[0031] The lower case 21 has a generally box-like shape that opens upward. The lower case 21 has thermal conductivity and is made of, for example, metal. The lower case 21 has a bottom wall 22, a peripheral wall 23, a flange 24, a base 25, a partition wall 211, and a reinforcing bracket 212 (see FIG. 2).

[0032] The bottom wall portion 22 is located below the multiple power storage stacks 10. The bottom wall portion 22 has an inner main surface 22a facing the power storage stacks 10 and an outer main surface 22b facing the side opposite to the side on which the power storage stacks 10 are located.

[0033] The peripheral wall portion 23 is provided so as to stand upright from the peripheral edge of the bottom wall portion 22. The flange portion 24 is provided so as to protrude outward from the upper end of the peripheral wall portion 23.

[0034] A plurality of partition walls 211 are provided. The partition walls 211 are arranged side by side in the DR2 direction at a predetermined interval. The partition walls 211 separate the areas in which the power storage stacks 10 are arranged at a predetermined interval. In the present embodiment, the partition walls 211 separate the areas in which the two power storage stacks 10 are arranged, but this is not limitative, and the positions of the partition walls 211 can be set appropriately. Both ends of the partition wall 211 in the DR1 direction are connected to the peripheral wall portion 23. The partition walls 211 reinforce the peripheral wall portion 23.

[0035] The pedestal portion 25 is provided so as to protrude upward from the center of the bottom wall portion 22 in the DR1 direction. A plurality of pedestal portions 25 are provided corresponding to each of the power storage stacks 10. The pedestal portion 25 is provided in each of the areas partitioned by the above-mentioned plurality of partition walls 211. The top portion 251 (see FIG. 3) of the pedestal portion 25 is formed flat. The intermediate plate 13 is placed on the top portion 251 of the pedestal portion 25. The pedestal portion 25 supports the intermediate plate 13.

[0036] The pedestal portion 25 includes a first pedestal portion 255 and a second pedestal portion 256. The first pedestal portion 255 and the second pedestal portion 256 are arranged spaced apart from each other in the DR2 direction. The first pedestal portion 255 supports one end of the intermediate plate 13 in the DR2 direction. The second pedestal portion 256 supports the other end of the intermediate plate 13 in the DR2 direction.

[0037] The reinforcing brackets 212 are arranged on both sides of the power storage stack 10 in the DR1 direction, between the peripheral wall portion 23 and the power storage stack 10. The reinforcing brackets 212 reinforce the attachment of the power storage stack 10 to the bottom wall portion 22.

[0038] The reinforcing bracket 212 has an upper end, a lower end, and a connecting portion connecting the upper end and the lower end. The upper end and the lower end have a flat plate shape extending in the DR1 direction away from the power storage stack 10, and the connecting portion is provided to extend in the up-down direction.

[0039] A lower end of the reinforcing bracket 212 is connected to the inner main surface 22a of the bottom wall portion 22 by, for example, welding, etc. An upper end of the reinforcing bracket 212 is connected to the flange portion 24 by, for example, welding, etc.

[0040] The upper case 26 has a generally box-like shape that opens downward and is made of, for example, metal.

[0041] Upper case 26 has a ceiling portion 27, a peripheral wall portion 28, and a flange portion 29. Ceiling portion 27 forms the upper wall of storage case 20. Peripheral wall portion 28 extends downward from the peripheral edge of ceiling portion 27. Flange portion 29 is provided so as to protrude outward from the lower end of peripheral wall portion 28.

[0042] The flange portions 24 and 29 are stacked one on top of the other in the vertical direction and fastened together with multiple fastening members (not shown), thereby allowing the upper case 26 and the lower case 21 to house multiple storage stacks 10 therein.

[0043] The cooler 30 is a device for cooling the multiple power storage stacks 10. The cooler 30 is arranged outside the housing case 20. Specifically, the cooler 30 is arranged below the bottom wall portion 22 of the lower case 21. An outer thermally conductive layer 40 is arranged between the cooler 30 and the outer main surface 22b. The cooler 30 is arranged outside the lower case 21 so as to be in thermal contact with the outer main surface 22b.

[0044] The cooler 30 is made of a metal material such as aluminum. The cooler 30 includes a plurality of main cooling sections 31 and a holding section 32. Inside the plurality of main cooling sections 31 and the holding section 32, a refrigerant flow path 31a (see FIG. 2) is arranged, through which a refrigerant flows for cooling the power storage stack 10. In the main cooling section 31, the refrigerant flows from the first cell group 11 side toward the second cell group 12 side, as shown by the arrow in FIG. 2.

[0045] The cooler 30 has a refrigerant inlet 33 and a refrigerant outlet 34. A refrigerant is introduced from the outside into the refrigerant flow path through the refrigerant inlet 33. The refrigerant is discharged from the refrigerant flow path through the refrigerant outlet 34.

[0046] The main cooling sections 31 are arranged side by side in a direction parallel to the DR2 direction. The main cooling sections 31 extend along the DR1 direction. Each of the main cooling sections 31 is arranged at a position facing the power storage stack 10 with the bottom wall section 22 interposed therebetween.

[0047] The holding part 32 holds the multiple main cooling parts 31. The holding part 32 is provided so as to hold at least both ends of the main cooling parts 31 in the DR1 direction. The holding part 32 is provided, for example, so as to include a pair of extending parts extending along the DR2 direction at both ends of the main cooling part 31. The holding part 32 may be provided in a frame shape so as to surround the multiple main cooling parts 31.

[0048] The outer thermally conductive layer 40 is made of a thermally conductive material and is disposed between the bottom wall portion 22 of the lower case 21 and the cooler 30. The outer thermally conductive layer 40 has a plurality of central thermally conductive portions 41 and an annular thermally conductive portion 42.

[0049] The plurality of central heat conducting portions 41 are disposed between each main cooling portion 31 and the bottom wall portion 22 of the lower case 21. The central heat conducting portions 41 have a shape that extends in the DR1 direction.

[0050] The annular heat conducting portion 42 has a shape that surrounds each central heat conducting portion 41. The annular heat conducting portion 42 is disposed between the holding portion 32 and the accommodating case 20. This prevents water from entering the space inside the annular heat conducting portion 42.

[0051] The outer thermally conductive layer 40 also functions as an adhesive layer, and adhesively fixes the cooler 30 to the bottom wall portion 22. The outer thermally conductive layer 40 is made of an adhesive containing a silicone resin, an acrylic resin, a urethane resin, an epoxy resin, or the like.

[0052] The shear panel 50 is disposed so as to cover the cooler 30 from below. The shear panel 50 protects the cooler 30 and also prevents the cooler 30 from being exposed to water. The shear panel 50 is made of a metal material.

[0053] The heat conduction member 60 is disposed between each power storage stack 10 and the bottom wall portion 22 (more specifically, the inner main surface 22a). The heat conduction member 60 also functions as an adhesive layer, and adhesively fixes each power storage stack 10 to the bottom wall portion 22.

[0054] The heat conduction member 60 has a first heat conduction member 61 and a second heat conduction member 62. The first heat conduction member 61 is disposed between the first cell group 11 and the bottom wall portion 22. The first heat conduction member 61 adhesively fixes the first cell group 11 to the bottom wall portion 22. The second heat conduction member 62 is disposed between the second cell group 12 and the bottom wall portion 22. The second heat conduction member 62 adhesively fixes the second cell group 12 to the bottom wall portion 22.

[0055] First heat conduction member 61 and second heat conduction member 62 are made of a resin material having thermal conductivity. For example, an adhesive containing a silicone resin, an acrylic resin, a urethane resin, or an epoxy resin can be used as first heat conduction member 61 and second heat conduction member 62. When first heat conduction member 61 and second heat conduction member 62 are made of the same material, the components can be simplified compared to when they are made of different materials.

[0056] The refrigerant flows from the first cell group 11 side toward the second cell group 12 side. That is, the second cell group 12 is cooled via the refrigerant that cooled the first cell group 11. Therefore, in order to suppress the temperature difference between the first cell group 11 and the second cell group 12, the thermal conductivity of the second heat conduction member 62 may be higher than the thermal conductivity of the first heat conduction member 61.

[0057] The pressing member 80 is a member that presses the power storage stack 10 toward the bottom wall portion 22. The pressing member 80 attaches the power storage stack 10 to the accommodating case 20 in a state in which the power storage stack 10 is pressed toward the bottom wall portion 22 so that the first heat conductive member 61 and the second heat conductive member 62 are pushed outward. The pressing member 80 has a first pressing portion 81 and a second pressing portion 82.

[0058] The first pressing portion 81 presses one end of the electricity storage stack 10 in the DR1 direction toward the bottom wall portion 22. The first pressing portion 81 has a bracket 811, an inner fastening member 812, and an outer fastening member 813.

[0059] The bracket 811 is a member for attaching the first cell group 11 to the accommodating case 20. The bracket 811 is made of metal. An inner end of the bracket 811 in the DR1 direction is fixed to one end of the electricity storage stack 10 by an inner fastening member 812. An outer end of the bracket 811 in the DR1 direction is fixed to an upper end of the reinforcing bracket 212 by an outer fastening member 813.

[0060] The second pressing portion 82 presses the other end of the electricity storage stack 10 in the DR1 direction toward the bottom wall portion 22. The second pressing portion 82 has a bracket 821, an inner fastening member 822, and an outer fastening member 823.

[0061] The bracket 821 is a member for attaching the second cell group 12 to the accommodating case 20. The bracket 821 is made of metal. An inner end of the bracket 821 in the DR1 direction is fixed to the other end of the electricity storage stack 10 by an inner fastening member 822. An outer end of the bracket 821 in the DR1 direction is fixed to the upper end of the reinforcing bracket 212 by an outer fastening member 823.

[0062] As described above, by pressing the first cell group 11 and the second cell group 12 toward the bottom wall portion 22 using the first pressing portion 81 and the second pressing portion 82, the first heat conduction member 61 arranged between the first cell group 11 and the bottom wall portion 22 and the second heat conduction member 62 arranged between the second cell group 12 and the bottom wall portion 22 can be spread out.

[0063] Fig. 3 is an enlarged partial cross-sectional view showing the periphery of the lower end of the intermediate plate of the energy storage device according to the embodiment. For convenience, the outer thermally conductive layer 40, the cooler 30, and the shear panel 50 are omitted from Fig. 3. The configuration of the periphery of the lower end of the intermediate plate 13 will be described with reference to Fig. 3.

[0064] 3, the base 25 includes a top 251 and inclined portions 252 and 253. The top 251 has a generally flat plate shape. The inclined portion 252 is connected to one end of the top 251 in the DR1 direction, and is inclined downward toward one side in the DR1 direction (one end side of the power storage stack 10). The inclined portion 253 is connected to the other end of the top in the DR1 direction, and is inclined downward toward the other side in the DR1 direction (the other end side of the power storage stack 10).

[0065] The intermediate plate 13 is placed on the base portion 25 (more specifically, the top portion 251). The intermediate plate 13 has a first end portion 13a located on the first cell group 11 side and a second end portion 13b located on the second cell group 12 side in the DR1 direction.

[0066] The intermediate plate 13 has a first protruding portion 131 that protrudes from the top 251 of the base portion 25 toward the first cell group 11 side, and a second protruding portion 132 that protrudes from the base portion 25 toward the second cell group 12 side.

[0067] First heat conducting member 61 is provided so as to be in contact with base portion 25. End portion 61a of first heat conducting member 61 located on the second heat conducting member 62 side is in contact with inclined portion 252. When viewed from a direction perpendicular to the arrangement direction, first heat conducting member 61 is provided so as to fill the space between first protruding portion 131 and base portion 25.

[0068] Second heat conducting member 62 is provided so as to be in contact with base portion 25. End portion 62a of second heat conducting member 62 located on the first heat conducting member 61 side is in contact with inclined portion 253. When viewed from a direction perpendicular to the arrangement direction, second heat conducting member 62 is provided so as to fill the space between second protruding portion 132 and base portion 25.

[0069] FIG. 4 is a schematic view showing an initial state of a step of attaching power storage stack 10 to lower case 21 via first and second heat conductive members in a manufacturing process of the power storage device according to the embodiment.

[0070] As shown in Figure 4, when attaching the storage stack 10 to the lower case 21 via the first heat conductive member 61 and the second heat conductive member 62, first, the first heat conductive member 61 and the second heat conductive member 62 are applied to the bottom wall portion 22 of the lower case 21, and then the bottom wall portion 22 and the storage stack 10 are positioned opposite each other.

[0071] FIG. 5 is a plan view of the first and second thermally conductive members applied to the bottom wall portion.

[0072] 5, the first heat conducting member 61 and the second heat conducting member 62 are applied to the inner main surface 22a of the bottom wall portion 22. The first heat conducting member 61 and the second heat conducting member 62 are applied so as to have a generally C-shape that opens toward the base portion 25. The first heat conducting member 61 and the second heat conducting member 62 may be applied continuously or intermittently at intervals. The first heat conducting member 61 and the second heat conducting member 62 are applied so as to leave a gap between them and the base portion 25.

[0073] The first thermally conductive member 61 is applied to have a first portion 611, a second portion 612, and a third portion 613. The first portion 611 and the second portion 612 are formed at an interval in the DR2 direction and extend along the DR1 direction. The third portion 613 is provided on the end side of the first portion 611 and the second portion 612 that is located on the opposite side in the DR2 direction from the side on which the base portion 25 is located. The third portion 613 is provided to extend in the DR2 direction.

[0074] Similarly, the second thermally conductive member 62 is applied to have a first portion 621, a second portion 622, and a third portion 623. The first portion 621 and the second portion 622 are formed at an interval in the DR2 direction and extend along the DR1 direction. The third portion 623 is provided on the end side of the first portion 621 and the second portion 622 that is located on the opposite side in the DR2 direction from the side on which the base portion 25 is located. The third portion 623 is provided to extend in the DR2 direction.

[0075] FIG. 6 is a schematic view showing a state midway through a step of attaching power storage stack 10 to lower case 21 via first and second heat conductive members in a manufacturing process for the power storage device according to the embodiment.

[0076] 6, in the mid-movement state, the power storage stack 10 is moved toward the bottom wall portion 22 so as to narrow the gap between the bottom surface of the power storage stack 10 and the bottom wall portion 22. At this time, the first heat conductive member 61 and the second heat conductive member 62 are sandwiched between the first cell group 11, the second cell group 12 and the bottom wall portion 22 and are pushed apart.

[0077] FIG. 7 is a diagram schematically showing the movement of air between the bottom surface and the bottom wall portion of the electricity storage stack in the intermediate state shown in FIG.

[0078] 7, when the first heat conductive member 61 and the second heat conductive member 62 are spread out, air in spaces S1 and S2 surrounded by the first heat conductive member 61, the second heat conductive member 62, the bottom surface of the power storage stack 10, and the bottom wall portion 22 can be released from around the base portion 25 to the outside of the power storage stack 10, as shown by the arrows in the figure. The spread first heat conductive member 61 and second heat conductive member 62 fill the spaces between the first cell group 11, the second cell group 12, and the bottom wall portion 22.

[0079] In this way, by spreading out the first heat conductive member 61 and the second heat conductive member 62 while allowing air to escape, it is possible to improve the adhesion between the power storage stack 10 and the bottom wall portion 22 of the lower case 21. In addition, by allowing air to escape from around both the first pedestal portion 255 and the second pedestal portion 256, it is possible to further improve the adhesion.

[0080] FIG. 8 is a schematic view showing a state after a step of attaching power storage stack 10 to lower case 21 via first and second thermal conductive members in a manufacturing process of the power storage device according to the embodiment.

[0081] 8, in the rear state, intermediate plate 13 is placed on base portion 25, and first heat conduction member 61 and second heat conduction member 62 are in contact with base portion 25. In this manner, first heat conduction member 61 and second heat conduction member 62 are pushed apart, thereby ensuring a large area for first heat conduction member 61 and second heat conduction member 62. This makes it possible to maintain good thermal conductivity.

[0082] In this case, as described above, the first heat conduction member 61 fills the space between the first protrusion 131 and the base portion 25, and the second heat conduction member 62 fills the space between the second protrusion 132 and the base portion 25, thereby ensuring contact between the first heat conduction member 61 and the second heat conduction member 62 up to the ends of the first cell group 11 and the second cell group 12 located on the intermediate plate 13 side.

[0083] In addition, by using the pressing member 80, the first cell group 11 and the second cell group 12 can be pressed more firmly against the bottom wall portion 22, thereby further improving the adhesion of the power storage stack 10.

[0084] In the above description, the pressing member 80 is fixed to the reinforcing bracket 212, but the present invention is not limited to this, and the pressing member 80 may be fixed to the bottom wall portion 22. Furthermore, if the heat conduction member 60 can sufficiently fix the power storage stack 10 to the bottom wall portion 22, the pressing member 80 and the reinforcing bracket 212 may be omitted.

[0085] The embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is defined by the claims, and the meaning and scope of the claims are equivalent to the claims. Contains all changes within [Explanation of symbols]

[0086] REFERENCE SIGNS LIST 1 Energy storage device, 10 Energy storage stack, 11 First cell group, 12 Second cell group, 13 Intermediate plate, 13a First end, 13b Second end, 15 Energy storage cell, 16 End plate, 20 Housing case, 21 Lower case, 22 Bottom wall portion, 22a Inner main surface, 22b Outer main surface, 23 Peripheral wall portion, 24 Flange portion, 25 Base portion, 26 Upper case, 27 Ceiling portion, 28 Peripheral wall portion, 29 Flange portion, 30 Cooler, 31 Main cooling portion, 31a Refrigerant flow path, 32 Holding portion, 33 Refrigerant introduction portion, 34 Refrigerant discharge portion, 40 Outer heat conduction layer, 41 Central heat conduction portion, 42 Annular heat conduction portion, 50 Shear panel, 60 Heat conduction member, 61 First heat conduction member, 61a End portion, 62 Second heat conduction member, 62a End, 80 pressing member, 81 first pressing portion, 82 second pressing portion, 131 first protruding portion, 132 second protruding portion, 211 partition wall, 212 reinforcing bracket, 251 top portion, 252, 253 inclined portion, 611 first portion, 612 second portion, 613 third portion, 621 first portion, 622 second portion, 623 third portion, 811 bracket, 812 inner fastening member, 813 outer fastening member, 821 bracket, 822 inner fastening member, 823 outer fastening member.

Claims

1. a storage stack including a first cell group and a second cell group each including a plurality of storage cells, and an intermediate member disposed between the first cell group and the second cell group; A bottom wall portion; a first heat conduction member disposed between the first cell group and the bottom wall portion; a second heat conduction member disposed between the second cell group and the bottom wall portion, the first heat conducting member and the second heat conducting member are in contact with a lower surface of the intermediate member, a region where the first heat conducting member and the intermediate member are in contact with each other and a region where the second heat conducting member and the intermediate member are in contact with each other are spaced apart from each other.

2. The first thermal conductive member and the second thermal conductive member are adhesives, the first heat conduction member adhesively fixes the first cell group and the intermediate member to the bottom wall portion, The power storage device according to claim 1 , wherein the second heat conducting member adhesively fixes the second cell group and the intermediate member to the bottom wall portion.

3. A storage device as described in claim 1 or claim 2, further comprising a cooler provided in the bottom wall portion.

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