Energy storage device

Abstract

The present invention provides an energy storage cell capable of suppressing misalignment between energy storage cells that are arranged side by side. [Solution] The energy storage device 1 comprises an energy storage cell 100A, an energy storage cell 100B, and an adhesive 600. On the side surface 521A of the cell case 500A of the energy storage cell 100A, a recess 526A is formed that is recessed from the main surface 525A toward the gap Ga1 between the arc portion 340A and the arc portion 440A. On the side surface 521B of the cell case 500B of the energy storage cell 100B, a recess 526B is formed that is recessed from the main surface 525B toward the gap Ga2 between the arc portion 340B and the arc portion 440B. The adhesive 600 is embedded in each of the recesses 526A and 526B.

Description

Technical Field

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

Background Art

[0002] Japanese Patent Laid-Open No. 2021-089812 (Patent Document 1) discloses a battery module in which a plurality of secondary batteries are arranged side by side.

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of Invention

Problem to be Solved by Invention

[0004] In the battery module described in the above Patent Document 1, when secondary batteries (power storage cells) expand (contract) due to charge and discharge, positional deviation may occur between the secondary batteries.

[0005] The present disclosure has been made to solve the above problem, and an object of the present disclosure is to provide a power storage device capable of suppressing the occurrence of positional deviation between power storage cells arranged side by side.

Means for Solving Problem

[0006] A power storage device according to one aspect of the present disclosure includes a first power storage cell comprising a plurality of first wound electrode bodies arranged side by side in a first direction and a first housing case housing the plurality of first wound electrode bodies; a second power storage cell comprising a plurality of second wound electrode bodies arranged side by side in a first direction and a second housing case housing the plurality of second wound electrode bodies; and an adhesive disposed between the first housing case and the second housing case. Each of the plurality of first wound electrode bodies is wound around a first winding axis extending in an axial direction intersecting the first direction. Each of the plurality of second wound electrode bodies is wound around a second winding axis extending in an axial direction. The second power storage cell is positioned adjacent to the first power storage cell in a second direction intersecting the first direction and the axial direction. The first housing case includes a first side facing the second housing case in the second direction. The second housing case includes a second side facing the first housing case in the second direction. Each of the multiple first wound electrode bodies is positioned opposite the first side surface and includes a first arc portion having an arc shape when viewed from a position spaced apart from the first energy storage cell in the axial direction. Each of the multiple second wound electrode bodies is positioned opposite the second side surface and includes a second arc portion having an arc shape when viewed from a position spaced apart from the second energy storage cell in the axial direction. The first side surface includes a first main surface and has a first recess formed therein that slopes inward from the first main surface toward a first gap between the first arc portions aligned in the first direction. The second side surface includes a second main surface and has a second recess formed therein that slopes inward toward a second gap between the second arc portions aligned in the first direction. The adhesive is embedded in each of the first and second recesses. [Effects of the Invention]

[0007] According to this disclosure, it is possible to suppress misalignment between energy storage cells that are arranged side by side. [Brief explanation of the drawing]

[0008] [Figure 1] This is an exploded perspective view showing the configuration of the energy storage device according to the first embodiment. [Figure 2]This is a plan view showing the configuration of the energy storage device according to the first embodiment. [Figure 3] This is an exploded perspective view showing the configuration of the energy storage cell according to the first embodiment. [Figure 4] This is a cross-sectional view showing the configuration of a storage cell according to the first embodiment. [Figure 5] This is a plan view showing the configuration of the energy storage device according to the second embodiment. [Figure 6] This is a cross-sectional view showing the configuration of a storage cell according to the second embodiment. [Figure 7] This is a cross-sectional view along line VII-VII in Figure 5. [Modes for carrying out the invention]

[0009] Embodiments of this disclosure will be described with reference to the drawings. In the drawings referred to below, the same or equivalent components are given the same number.

[0010] (First Embodiment) Figure 1 is an exploded perspective view showing the configuration of the energy storage device 1 in a first embodiment of the present disclosure. The energy storage device 1 is mounted, for example, on a vehicle (not shown). Examples of vehicles include hybrid electric vehicles, plug-in hybrid electric vehicles, and battery electric vehicles. The energy storage device 1 may also be installed in electrical equipment other than a vehicle (for example, a stationary energy storage device).

[0011] In this specification, the X, Y, and Z directions are mutually orthogonal directions. For example, the X and Y directions may be the front-rear and rear-left and left-right directions, respectively, when the energy storage device 1 is mounted on a vehicle. The Z direction may also be the up-down direction. Specifically, the Z1 and Z2 directions may be upward and downward, respectively. The X and Y directions are examples of the "second direction" and "first direction" in this disclosure, respectively. The Z direction is an example of the "axial direction" in this disclosure.

[0012] The energy storage device 1 comprises a plurality of energy storage stacks 10, a housing case 20, an insulating plate 30, a panel member 40, a wiring panel 50, equipment 60, and a cooling device 70. Each energy storage stack 10 is formed in a rectangular parallelepiped shape that is elongated in the Y direction. The plurality of energy storage stacks 10 are arranged in the X direction. Each energy storage stack 10 contains a plurality of energy storage cells 100 arranged in the Y direction.

[0013] The housing case 20 houses multiple energy storage stacks 10, a wiring panel 50, equipment 60, and a cooling device 70. The housing case 20 includes a lower case 210 and an upper cover 220. The upper cover 220 is positioned above the lower case 210 (towards Z1).

[0014] The lower case 210 is formed to open upward. The lower case 210 is made of a metal such as aluminum. The lower case 210 includes a bottom plate 211, a peripheral wall 212, a partition wall 213, and a partition wall 214.

[0015] The base plate 211 is formed in a plate shape. Multiple through holes 211h are formed in the base plate 211 at intervals in the X and Y directions.

[0016] The peripheral wall 212 rises from the outer edge of the base plate 211. The peripheral wall 212 has a shape that surrounds multiple energy storage stacks 10.

[0017] End plate 212c and end plate 212d are arranged at intervals in the Y direction. End plate 212c and end plate 212d are formed to extend in the X direction. End plate 212c connects one end of side wall 212a and one end of side wall 212b. End plate 212d connects the other end of side wall 212a and the other end of side wall 212b.

[0018] Partition wall 213 and partition wall 214 are arranged in a region surrounded by bottom plate 211 and peripheral wall 212. Partition wall 213 is arranged adjacent to end plate 212c. Partition wall 214 is arranged at an interval in the Y direction with respect to end plate 212d. Each of partition wall 213 and partition wall 214 is formed to extend in the X direction. Partition wall 213 and partition wall 214 have a function of restraining each power storage stack 10 from both sides in the Y direction.

[0019] In the space formed by lower case 210 and upper cover 220, a plurality of power storage stacks 10, a wiring panel 50, devices 60, and a cooling device 70 are accommodated.

[0020] Insulating plate 30 is made of an electrically insulating member (for example, a resin composition). Insulating plate 30 is formed in a plate shape, for example. In insulating plate 30, a plurality of through holes 30h are formed at intervals in the X direction and the Y direction. Insulating plate 30 is arranged between panel member 40 and bottom plate 211 of lower case 210. Insulating plate 30 is fixed to the lower surface of bottom plate 211.

[0021] Panel member 40 has a function of protecting bottom plate 211 of lower case 210. Panel member 40 is formed so as to cover insulating plate 30 and the lower surface of bottom plate 211. Panel member 40 is formed in a plate shape, for example.

[0022] Wiring panel 50 is arranged below the plurality of power storage stacks 10. Wiring panel 50 includes an insulating plate 51, a plurality of bus bar modules 500, and a plurality of insulating protectors 52.

[0023] The insulating plate 51 is made of an electrically insulating material (for example, a resin composition). For example, the insulating plate 51 is made of a flexible resin. The insulating plate 51 is formed, for example, in the shape of a plate. The insulating plate 51 is located on the upper surface 211a of the bottom plate 211 of the lower case 210, in the portion located between the partition wall 213 and the partition wall 214.

[0024] Multiple through holes 51h are formed in the insulating plate 51, spaced apart in the X and Y directions.

[0025] Multiple busbar modules 500 are provided on the upper surface 51a of the insulating plate 51. Each busbar module 500 includes one or more busbars 510. Each of the multiple busbar modules 500 includes multiple busbars 510 arranged in the Y direction. Note that the number of busbar rows included in a busbar module 500 may be one. Also, the number of busbars 510 included in a busbar row may be one.

[0026] The busbar 510 is formed from a conductive material such as a metal. The busbar 510 electrically connects a pair of adjacent energy storage cells 100 in the Y direction.

[0027] The energy storage stack 10 is positioned on the top surface of the busbar module 500. The external terminals of the multiple energy storage cells 100 included in the energy storage stack 10 are connected to the busbar module 500, thereby electrically connecting the multiple energy storage cells 100 in series.

[0028] The insulating protector 52 is made of a heat-resistant material (for example, mica). The insulating protector 52 is provided on the upper surface 51a of the insulating plate 51. The insulating protector 52 is provided to close a plurality of through holes 51h arranged in the Y direction. The insulating protector 52 includes a band portion 52a extending in the Y direction and a plurality of closing portions 52b formed on the lower surface of the band portion 52a. Each closing portion 52b is located within the through holes 51h.

[0029] The cooling device 70 includes a plurality of cooling plates 71, an equipment cooler 72, upstream piping 73, and downstream piping 74. The cooling plates 71 are an example of the "cooling piping" in this disclosure.

[0030] Each cooling plate 71 is positioned between a pair of adjacent energy storage stacks 10 in the X direction. Each cooling plate 71 is formed in a long, plate-like shape in the Y direction. Each cooling plate 71 has a flow path through which a coolant flows along the Y direction. In the first embodiment, the number of cooling plates 71 is 5, but the number of cooling plates 71 is not limited to 5. The number of cooling plates 71 is determined according to the number of energy storage stacks 10.

[0031] The equipment cooler 72 cools the equipment 60. The equipment cooler 72 is installed between the bottom plate 211 and the equipment 60.

[0032] Figure 2 is a schematic plan view showing the energy storage device shown in Figure 1 with the upper cover 220 removed.

[0033] The upstream piping 73 and the downstream piping 74 are pipes through which refrigerant (water, oil, etc.) flows. An inlet port 75 and an outlet port 76 are provided on the end plate 212c of the peripheral wall 212.

[0034] The upstream end of the upstream piping 73 is connected to the inlet port 75. The upstream piping 73 has six downstream ends. One downstream end of the upstream piping 73 is connected to the equipment cooler 72. Each of the remaining downstream ends of the upstream piping 73 is connected to the cooling plate 71.

[0035] The downstream piping 74 has six upstream ends. One upstream end of the downstream piping 74 is connected to the equipment cooler 72. Each of the remaining upstream ends of the downstream piping 74 is connected to the cooling plate 71. The downstream end of the downstream piping 74 is connected to the outlet port 76. The refrigerant supplied from the inlet port 75 flows through the upstream piping 73 to each cooling plate 71 and the equipment cooler 72, cools each energy storage cell 100 and equipment 60, and then flows out through the downstream piping 74 to the outlet port 76.

[0036] Each cooling plate 71 is positioned between a pair of adjacent energy storage cells 100 in the X direction. Each cooling plate 71 is formed in a long, plate-like shape in the X direction.

[0037] The side wall 212a, the side wall 212b, the end plate 212c, and the end plate 212d are each provided with fixing parts 90, 91, 92, and 93, respectively. Each of the fixing parts 90 to 93 is fixed to the vehicle body (not shown).

[0038] Figure 3 is a perspective view showing a pair of adjacent energy storage cells 100 in the X direction. In the following description, the energy storage cell 100 on the X1 side will be referred to as energy storage cell 100A, and the energy storage cell 100 on the X2 side will be referred to as energy storage cell 100B. Energy storage cells 100A and 100B have the same configuration.

[0039] Energy storage cell 100A includes a wound electrode body 300A, a wound electrode body 400A, a cell case 500A, a positive electrode current collector plate 110A, and a negative electrode current collector plate 120A. Energy storage cell 100B includes a wound electrode body 300B, a wound electrode body 400B, a cell case 500B, a positive electrode current collector plate 110B, and a negative electrode current collector plate 120B. Energy storage cell 100A and energy storage cell 100B are examples of the "first energy storage cell" and "second energy storage cell" of this disclosure, respectively. Furthermore, the wound electrode body 300A is an example of the "first wound electrode body" and "second electrode body" of this disclosure. The wound electrode body 400A is an example of the "first wound electrode body" and "first electrode body" of this disclosure. The wound electrode 300B is an example of the "second wound electrode" and "fourth electrode" of this disclosure. The wound electrode 400B is an example of the "second wound electrode" and "third electrode" of this disclosure. Furthermore, the cell case 500A and cell case 500B are examples of the "first housing case" and "second housing case" of this disclosure, respectively.

[0040] Energy storage cells 100A and 100B have the same configuration. The wound electrode body 300B, wound electrode body 400B, cell case 500B, positive electrode current collector plate 110B, and negative electrode current collector plate 120B correspond to the wound electrode body 300A, wound electrode body 400A, cell case 500A, positive electrode current collector plate 110A, and negative electrode current collector plate 120A, respectively. In the following, the explanation of components of energy storage cell 100B that are the same as those of energy storage cell 100A may be omitted or simplified.

[0041] The wound electrode bodies 300A and 400A are arranged side by side in the Y direction. The wound electrode bodies 300A and 400A have the same configuration.

[0042] The wound electrode body 300A is wound around a winding axis α1 extending in the Z direction. The wound electrode body 400A is wound around a winding axis α2 extending in the Z direction. The position of the winding axis α1 in the X direction and the position of the winding axis α2 in the X direction are the same. Note that each of the winding axis α1 and winding axis α2 is an example of the "first winding axis" in this disclosure.

[0043] Similar to the wound electrode bodies 300A and 400A, the wound electrode body 300B is wound around a winding axis β1 extending in the Z direction, and the wound electrode body 400B is wound around a winding axis β2 extending in the Z direction. Note that each of the winding axis β1 and winding axis β2 is an example of the "second winding axis" in this disclosure.

[0044] The wound electrode body 300A includes a wound portion 310A, a positive electrode tab 320A, and a negative electrode tab 330A.

[0045] The winding section 310A is composed of a group of electrode plates in which a positive electrode sheet (not shown) and a negative electrode sheet (not shown) are wound around one or more separators (not shown).

[0046] The positive electrode tab 320A protrudes from the winding portion 310A toward the Z1 side. The positive electrode tab 320A electrically connects the winding portion 310A (positive electrode sheet) and the positive electrode current collector plate 110A. The positive electrode current collector plate 110A is electrically connected to the external positive electrode terminal (not shown) of the energy storage cell 100A.

[0047] The negative electrode tab 330A protrudes from the winding portion 310A toward the Z1 side. The negative electrode tab 330A electrically connects the winding portion 310A (negative electrode sheet) and the negative electrode current collector plate 120A. The negative electrode current collector plate 120A is electrically connected to the external negative electrode terminal (not shown) of the energy storage cell 100A.

[0048] The wound electrode body 400A includes a wound portion 410A, a positive electrode tab 420A, and a negative electrode tab 430A. The wound portion 410A, the positive electrode tab 420A, and the negative electrode tab 430A each have the same configuration as the wound portion 310A, the positive electrode tab 320A, and the negative electrode tab 330A, respectively.

[0049] The wound electrode body 300B includes a wound portion 310B, a positive electrode tab 320B, and a negative electrode tab 330B. The wound electrode body 400B includes a wound portion 410B, a positive electrode tab 420B, and a negative electrode tab 430B.

[0050] The cell case 500A houses the wound electrode bodies 300A and 400A. The cell case 500A includes a bottom surface 510A and a peripheral wall 520A. The wound electrode bodies 300A and 400A are surrounded by the peripheral wall 520A when viewed from a position P1 spaced Z1 away from the cell case 500A.

[0051] The peripheral wall 520A has side surfaces 521A, 522A, 523A, and 524A. Side surface 521A is an example of the "first side surface" of this disclosure.

[0052] Side 521A is located at the X2 side (cell case 500B side) of the cell case 500A. Side 522A is located at the X1 side of the cell case 500A. Side 523A is located at the Y2 side of the cell case 500A. Side 524A is located at the Y1 side of the cell case 500A.

[0053] An exhaust valve 511A is provided on the bottom surface 510A. The exhaust valve 511A is a pressure relief valve that discharges gas to the outside of the cell case 500A when the internal gas pressure in the cell case 500A exceeds a certain level.

[0054] The cell case 500B houses the wound electrode bodies 300B and 400B. The cell case 500B includes a bottom surface 510B and a peripheral wall 520B. The wound electrode bodies 300B and 400B are surrounded by the peripheral wall 520B when viewed from a position P2 spaced Z1 away from the cell case 500B.

[0055] The peripheral wall 520B has side surfaces 521B, 522B, 523B, and 524B. Side surface 521B is an example of the "second side surface" of this disclosure.

[0056] Side 521B is located at the X1 side (cell case 500A side) of the cell case 500B. Side 522B is located at the X2 side of the cell case 500B. Side 523B is located at the Y2 side of the cell case 500B. Side 524B is located at the Y1 side of the cell case 500B.

[0057] An exhaust valve 511B is provided on the bottom surface 510B. The exhaust valve 511B is a pressure relief valve, similar to the exhaust valve 511A.

[0058] The energy storage device 1 (Figure 2) further comprises an adhesive 600. The adhesive 600 is placed between cell case 500A and cell case 500B. The adhesive 600 may be made of a resin (for example, epoxy resin). Note that the material of the adhesive 600 is not limited to this example.

[0059] The cooling plate 71 passes through the adhesive 600. This allows the coolant circulating through the cooling plate 71 to effectively cool each of the energy storage cells 100A and 100B. In addition, the energy storage cells 100A and 100B can cool the adhesive 600.

[0060] The adhesive 600 includes an adhesive layer 610 and an adhesive layer 620. The adhesive layer 610 is placed (filled) between the cell case 500A and the cooling plate 71. The adhesive layer 620 is placed (filled) between the cell case 500B and the cooling plate 71.

[0061] The side surface 521A of the cell case 500A includes the main surface 525A. Furthermore, a recess 526A is formed on the side surface 521A, recessing toward X1 from the main surface 525A. The recess 526A extends from the Z1 end of the cell case 500A to the Z2 end of the cell case 500A. The main surface 525A and the recess 526A are examples of the "first main surface" and "first recess" as defined in this disclosure, respectively.

[0062] A recess 527A, which has the same shape as recess 526A, is also formed on the side 522A of the cell case 500A.

[0063] The side surface 521B of the cell case 500B includes the main surface 525B. Furthermore, a recess 526B is formed on the side surface 521B, extending inward from the main surface 525B towards X2. The recess 526B extends from the Z1 end of the cell case 500B to the Z2 end of the cell case 500B. The main surface 525B and the recess 526B are examples of the "second main surface" and "second recess" as defined in this disclosure, respectively.

[0064] A recess 527B is also formed on the side 522B of the cell case 500B, similar to the recess 526B.

[0065] The wound electrode body 300A (winding portion 310A) includes an arc portion 340A and an arc portion 350A. The arc portion 340A is provided at the X2 side end of the wound electrode body 300A. The arc portion 350A is provided at the X1 side end of the wound electrode body 300A. Each of the arc portion 340A and the arc portion 350A has an arc shape when viewed from a position P1 spaced apart from the energy storage cell 100A in the Z direction. The arc portion 340A is an example of the "first arc portion" of this disclosure.

[0066] The wound electrode body 400A (winding portion 410A) includes an arc portion 440A and an arc portion 450A. The arc portion 440A is provided at the X2 side end of the wound electrode body 400A. The arc portion 450A is provided at the X1 side end of the wound electrode body 300A. Each of the arc portions 440A and 450A has an arc shape when viewed from position P1. Note that the arc portion 440A is an example of the "first arc portion" of this disclosure.

[0067] The wound electrode body 300B (winding portion 310B) includes an arc portion 340B and an arc portion 350B. The arc portion 340B is provided at the X1 side end of the wound electrode body 300B. The arc portion 350B is provided at the X2 side end of the wound electrode body 300B. Each of the arc portions 340B and 350B has an arc shape when viewed from a position P2 spaced apart from the energy storage cell 100B in the Z direction. Note that the arc portion 340B is an example of the "second arc portion" of this disclosure.

[0068] The wound electrode body 400B (winding portion 410B) includes an arc portion 440B and an arc portion 450B. The arc portion 440B is provided at the X1 side end of the wound electrode body 400B. The arc portion 450B is provided at the X2 side end of the wound electrode body 400B. Each of the arc portions 440B and 450B has an arc shape when viewed from position P2. Note that the arc portion 440B is an example of the "second arc portion" of this disclosure.

[0069] Figure 4 is a magnified view of the area near the adhesive 600 in the cross-sectional views of energy storage cells 100A and 100B.

[0070] As shown in Figure 4, each of the arc sections 340A and 440A is positioned opposite the side surface 521A. Each of the arc sections 340B and 440B is positioned opposite the side surface 521B.

[0071] Arc portion 340A and arc portion 440A are arranged side by side in the Y direction. A gap Ga1 is formed between arc portion 340A and arc portion 440A. Arc portion 340B and arc portion 440B are arranged side by side in the Y direction. A gap Ga2 is formed between arc portion 340B and arc portion 440B. Note that gaps Ga1 and Ga2 are examples of the "first gap" and "second gap" of this disclosure, respectively.

[0072] The recess 526A is formed so as to be recessed from the main surface 525A of the cell case 500A toward the gap Ga1. The recess 526B is formed so as to be recessed from the main surface 525B of the cell case 500B toward the gap Ga2.

[0073] In conventional modules, when energy storage cells expand (or contract) due to charging and discharging, misalignment can occur between the energy storage cells.

[0074] In the first embodiment, the adhesive 600 (adhesive layer 610) is embedded in the recess 526A. The adhesive 600 (adhesive layer 620) is embedded in the recess 526B.

[0075] Side surface 521A includes a defining surface 528A that defines a recess 526A. Side surface 521B includes a defining surface 528B that defines a recess 526B. The defining surface 528B is located adjacent to the defining surface 528A in the X direction. That is, the defining surface 528B is located in the same position as the defining surface 528A in the Y direction. Note that only a portion of the defining surface 528B may be located within the range in the Y direction where the defining surface 528A is located. Furthermore, the defining surface 528A and the defining surface 528B are examples of the "first defining surface" and the "second defining surface" of this disclosure, respectively.

[0076] The specified surface 528A extends from the main surface 525A into the gap Ga1. The specified surface 528B extends from the main surface 525B into the gap Ga2.

[0077] The specified surface 528A has an inclined surface 5280A and an inclined surface 5281A. The inclined surface 5280A is positioned on the Y1 side relative to the inclined surface 5281A. The inclined surface 5280A is inclined in a direction away from the energy storage cell 100B (towards X1) as it approaches the inclined surface 5281A side (towards Y2). The inclined surface 5281A is inclined in a direction away from the energy storage cell 100B as it approaches the inclined surface 5280A side (towards Y1). The X1 side ends of the inclined surface 5280A and the inclined surface 5281A are connected to each other. The inclined surface 5280A and the inclined surface 5281A are examples of the "first inclined surface" and the "second inclined surface" of this disclosure, respectively.

[0078] The specified surface 528B has an inclined surface 5280B and an inclined surface 5281B. The inclined surface 5280B is positioned on the Y1 side relative to the inclined surface 5281B. The inclined surface 5280B is inclined away from the energy storage cell 100A (towards the X2 side) as it approaches the inclined surface 5281B side (towards the Y2 side). The inclined surface 5281B is inclined away from the energy storage cell 100A as it approaches the inclined surface 5280B side (towards the Y1 side). The X2 side ends of the respective inclined surfaces 5280B and 5281B are connected to each other. The inclined surfaces 5280B and 5281B are examples of the "third inclined surface" and "fourth inclined surface" of this disclosure, respectively.

[0079] The inclined surface 5280A is in contact with the arc portion 440A of the wound electrode body 400A. The inclined surface 5281A is in contact with the arc portion 340A of the wound electrode body 300A. The inclined surface 5280B is in contact with the arc portion 440B of the wound electrode body 400B. The inclined surface 5281B is in contact with the arc portion 340B of the wound electrode body 300B. This makes it easy to enlarge the respective spaces of the recesses 526A and 526B, and thus allows for an increase in the amount of adhesive 600 filled into each of the recesses 526A and 526B.

[0080] In the first embodiment, the inclined surfaces 5280A, 5281A, 5280B, and 5281B are each formed in a flat shape, but the defining surface that defines the recess may be curved, for example. Also, the recesses 526A and 526B each have a triangular shape when viewed from the Z1 side, but they may have a rectangular shape when viewed from the Z1 side, for example.

[0081] The adhesive layer 610 includes adhesive portion 611 and adhesive portion 612. The adhesive layer 620 includes adhesive portion 621 and adhesive portion 622.

[0082] Each of the adhesive portions 611 and 621 is positioned between the main surface 525A of the cell case 500A and the main surface 525B of the cell case 500B. Specifically, adhesive portion 611 is sandwiched in the X direction between the main surface 525A and the cooling plate 71. Adhesive portion 621 is sandwiched in the X direction between the main surface 525B and the cooling plate 71.

[0083] Each of the adhesive portions 612 and 622 is positioned between the specified surface 528A of the cell case 500A and the specified surface 528B of the cell case 500B. Specifically, adhesive portion 612 is sandwiched in the X direction between the specified surface 528A and the cooling plate 71. Adhesive portion 622 is sandwiched in the X direction between the specified surface 528B and the cooling plate 71.

[0084] As a result, the energy storage cell 100A can be stably fixed by the cooling plate 71 compared to the case where the adhesive layer 610 includes only the adhesive portion 612. Similarly, the energy storage cell 100B can be stably fixed by the cooling plate 71.

[0085] The adhesive portion 611 includes a portion between the wound electrode body 300A and the cooling plate 71 (hereinafter referred to as the first portion) and a portion between the wound electrode body 400A and the cooling plate 71 (hereinafter referred to as the second portion). The adhesive portion 612 is positioned between the first portion and the second portion of the adhesive portion 611 and is integrally formed with the first portion and the second portion of the adhesive portion 611.

[0086] The adhesive portion 621 includes a portion between the wound electrode body 300B and the cooling plate 71 (hereinafter referred to as the first portion) and a portion between the wound electrode body 400B and the cooling plate 71 (hereinafter referred to as the second portion). The adhesive portion 622 is positioned between the first portion and the second portion of the adhesive portion 621 and is integrally formed with the first portion and the second portion of the adhesive portion 621.

[0087] The inside of the cooling plate 71 has a flow path 71a through which the coolant flows. The flow path 71a extends in the Y direction. Multiple flow paths 71a may be arranged in the Z direction.

[0088] The cooling plate 71 is formed so that its thickness in the X direction is constant. Therefore, the thickness of the adhesive portion 612 in the X direction is greater than the thickness of the adhesive portion 611 in the X direction. The thickness of the adhesive portion 612 in the X direction gradually increases as it approaches the connection point between the inclined surface 5280A and the inclined surface 5281A. The same applies to the adhesive portions 621 and 622.

[0089] As described above, in the first embodiment, the adhesive 600 penetrates into recesses 526A and 526B, respectively. This allows the cell case 500A and the cooling plate 71 to be bonded by the adhesive 600 that penetrates into recess 526A, and the cell case 500B and the cooling plate 71 to be bonded by the adhesive 600 that penetrates into recess 526B. As a result, misalignment between energy storage cells 100A and 100B can be suppressed.

[0090] Furthermore, because the adhesive 600 is embedded in the recess 526A (recess 526B), even if a force (frictional force) is applied to the adhesive 600 in the Y direction, it is possible to suppress the peeling of the adhesive 600 from the side surface 521A (side surface 521B) due to the adhesive 600 being pulled in the Y direction.

[0091] (Second Embodiment) Next, a second embodiment of the present disclosure will be described with reference to Figures 5 to 7. The energy storage device 11 of the second embodiment includes a cooling device 170 in place of the cooling device 70 of the first embodiment. Components that are the same as those of the first embodiment will be denoted by the same reference numerals as in the first embodiment and will not be described repeatedly.

[0092] As shown in Figure 5, the energy storage device 11 includes a cooling device 170. The cooling device 170 includes a plurality of refrigerant pipes 171, a plurality of cooling plates 172, a plurality of supply pipes 173, a plurality of discharge pipes 174, a plurality of connecting pipes 175 (Figure 6), a plurality of refrigerant pipes 176 (Figure 7), an equipment cooler 72, upstream piping 73, and downstream piping 74. Note that the connecting pipes 175 are an example of "cooling piping" in this disclosure.

[0093] Each of the multiple cooling plates 172 is positioned between adjacent energy storage cells 100 in the Y direction. Each of the multiple cooling plates 172 extends in the X direction and connects the supply pipe 173 and the discharge pipe 174.

[0094] Each of the multiple supply pipes 173 extends in the Y direction along the upstream piping 73 and supplies refrigerant from the upstream piping 73 to each cooling plate 172. The multiple supply pipes 173 are arranged side by side in the X direction.

[0095] Each of the multiple discharge pipes 174 extends in the Y direction along the downstream piping 74, discharging refrigerant from each cooling plate 172 into the downstream piping 74. The multiple discharge pipes 174 are arranged side by side in the X direction.

[0096] The refrigerant that has flowed through the upstream piping 73 flows into each refrigerant pipe 171. Each refrigerant pipe 171 is positioned between adjacent energy storage cells 100 in the X direction when viewed from a position spaced apart from the energy storage device 11 towards Z1. Each refrigerant pipe 171 extends in the Y direction along the energy storage stack 10. The refrigerant that has flowed through each refrigerant pipe 171 is discharged from the outlet port 76.

[0097] As shown in Figure 6, in the following description, the cooling plate 172 located on the Y1 side of energy storage cells 100A and 100B will be referred to as cooling plate 172a, and the cooling plate 172 located on the Y2 side of energy storage cells 100A and 100B will be referred to as cooling plate 172b. Cooling plate 172a and cooling plate 172b are examples of the "first cooler" and "second cooler" of this disclosure, respectively.

[0098] The cooling plate 172a is positioned across side surface 524A of cell case 500A and side surface 524B of cell case 500B. The cooling plate 172a may be in contact with side surfaces 524A and 524B. Side surfaces 524A and 524B are examples of the "first case side surface" and "third case side surface" of this disclosure, respectively.

[0099] The cooling plate 172b is positioned across side surface 523A of cell case 500A and side surface 523B of cell case 500B. The cooling plate 172b may be in contact with side surfaces 523A and 523B. Side surfaces 523A and 523B are examples of the "second case side surface" and "fourth case side surface" of this disclosure, respectively.

[0100] The energy storage device 11 (Figure 5) includes an adhesive 1600. The adhesive 1600 is placed (filled) in the space between energy storage cells 100A and 100B, which are arranged side by side in the X direction.

[0101] In the second embodiment, the adhesive 1600 extends in the Y direction and is connected to each of the cooling plates 172a and 172b. That is, the adhesive 1600 is bonded to each of the cooling plates 172a and 172b.

[0102] As a result, the cooling plate 172a and the cooling plate 172b are connected by the adhesive 1600, which helps to prevent misalignment between the cooling plate 172a and the cooling plate 172b.

[0103] The connecting pipe 175 passes through the adhesive 1600. In the cross-sectional view shown in Figure 6, the connecting pipe 175 has an annular shape. The connecting pipe 175 is positioned between the defining surface 528A that defines the recess 526A and the defining surface 528B that defines the recess 526B. A portion of the connecting pipe 175 may be inserted into each of the recesses 526A and 526B.

[0104] The connecting pipe 175 extends in the Z direction within the adhesive 1600. As a result, the refrigerant flowing through the connecting pipe 175 passes through the space between the energy storage cells 100A and 100B, so that the energy storage cells 100A and 100B can be effectively cooled by the refrigerant flowing through the connecting pipe 175. In addition, the extension of the connecting pipe 175 in the Z direction prevents it from interfering with the cooling plate 172.

[0105] Figure 7 is a cross-sectional view along the line VII-VII in Figure 5. The connecting pipe 175 penetrates the adhesive 1600 in the Z direction. The connecting pipe 175 communicates with each of the refrigerant pipes 171 and 176. The refrigerant pipes 176 extend in the Y direction below each of the refrigerant pipes 171 (towards the Z2 side). The connecting pipe 175 may be formed integrally with each of the refrigerant pipes 171 and 176.

[0106] A portion of the refrigerant flowing through refrigerant pipe 171 passes through connecting pipe 175 and then flows into refrigerant pipe 176. The refrigerant that flows into refrigerant pipe 176 flows towards Y1 and is then discharged from outlet port 76 (Figure 5) which is connected to refrigerant pipe 176. The dashed line in Figure 7 shows the flow of the refrigerant.

[0107] Each of the cooling plates 172a and 172b has multiple flow channels 172c formed within it. The multiple flow channels 172c are arranged in the Z direction in each of the cooling plates 172a and 172b.

[0108] The other components are the same as those in the first embodiment described above, so we will not repeat them.

[0109] <Variation> In the first and second embodiments described above, examples were shown in which the adhesive is placed between the main surface 525A and the main surface 525B, and between the specified surface 528A and the specified surface 528B, respectively, but the disclosure is not limited thereto. The adhesive may be placed only between the specified surface 528A and the specified surface 528B.

[0110] In the first and second embodiments described above, examples were shown in which cooling pipes (70, 175) through which a refrigerant flows pass inside the adhesive, but the disclosure is not limited thereto. Cooling pipes do not need to pass inside the adhesive.

[0111] The configurations of each of the above embodiments and each of the modified examples may be combined with each other.

[0112] It should be noted that the embodiments disclosed herein are illustrative in all respects and not restrictive. The scope of this disclosure is defined by the claims rather than the description of the embodiments above, and includes all modifications within the meaning and scope equivalent to the claims. [Explanation of Symbols]

[0113] 1,11 Energy storage device, 71 Cooling plate (cooling piping), 100A Energy storage cell (first energy storage cell), 100B Energy storage cell (second energy storage cell), 172a Cooling plate (first cooler), 172b Cooling plate (second cooler), 175 Connecting pipe (cooling piping), 300A Winding electrode body (first winding electrode body) (second electrode body), 300B Winding electrode body (second winding electrode body) (fourth electrode body), 340A,440A Arc section (first arc section), 340B,440B Arc section (second arc section), 400A Winding electrode body (first winding electrode body) (first electrode body), 400B Winding electrode body (second winding electrode body) (third electrode body), 500A Cell case (first housing case), 500B Cell case (second housing case), 521A side (first side), 521B side (second side), 523A side (second case side), 524A side (first case side), 523B side (fourth case side), 524B side (third case side), 525A main surface (first main surface), 525B main surface (second main surface), 526A recess (first recess), 526B recess (second recess), 528A standard surface (first standard surface), 528B standard surface (second standard surface), 600, 1600 adhesive, 5280A inclined surface (first inclined surface), 5281A inclined surface (second inclined surface), 5280B inclined surface (third inclined surface), 5281B inclined surface (fourth inclined surface), Ga1 Gap (first gap), Ga2 gap (second gap), P1, P2 positions (spaced positions), α1, α2 winding axes (first winding axis), β1, β2 winding axes (second winding axis).

Claims

1. A first energy storage cell comprising a plurality of first wound electrode bodies arranged in a first direction, and a first housing case for housing the plurality of first wound electrode bodies, A second energy storage cell comprising a plurality of second wound electrode bodies arranged in the first direction, and a second housing case for housing the plurality of second wound electrode bodies, The device comprises an adhesive material placed between the first storage case and the second storage case, Each of the plurality of first wound electrode bodies is wound around a first winding axis that extends in an axial direction intersecting the first direction, Each of the plurality of second wound electrode bodies is wound around a second winding axis extending in the axial direction, The second energy storage cell is positioned adjacent to the first energy storage cell in a second direction that intersects with the first direction and the axial direction, The first housing case includes a first side surface that is positioned on the second housing case side in the second direction, The second housing case includes a second side surface that is positioned on the first housing case side in the second direction, Each of the plurality of first wound electrode bodies is positioned opposite the first side surface and includes a first arc portion having an arc shape when viewed from a position spaced apart from the first energy storage cell in the axial direction. Each of the plurality of second wound electrode bodies is positioned opposite the second side surface and includes a second arc portion having an arc shape when viewed from a position spaced apart from the second energy storage cell in the axial direction. The first side surface includes a first main surface, and a first recess is formed from the first main surface toward a first gap between the first circular arc portions aligned in the first direction. The second side surface includes a second main surface, and a second recess is formed from the second main surface toward the second gap between the second arc portions aligned in the first direction. The adhesive is embedded in the first recess and the second recess of the energy storage device.

2. The energy storage device according to claim 1, further comprising a cooling pipe passing through the adhesive material.

3. The system further comprises a first cooler and a second cooler extending in the second direction, The aforementioned first containment case is The first case side on one side in the first direction, Including the second case side on the other side in the first direction, The aforementioned second storage case is The third case side on one side in the first direction, Including the fourth case side on the other side in the first direction, The first cooler is positioned across the first case side and the third case side, The second cooler is positioned across the second case side and the fourth case side, The energy storage device according to claim 1 or 2, wherein the adhesive extends in the first direction and is connected to each of the first cooler and the second cooler.

4. The adhesive further comprises a cooling pipe passing through the adhesive, The energy storage device according to claim 3, wherein the cooling pipe extends axially within the adhesive.

5. The first side surface includes a first defining surface that defines the first recess, The second side surface includes a second defining surface that defines the second recess, The first defined surface has a first inclined surface and a second inclined surface that is connected to the first inclined surface and is positioned on one side in the first direction relative to the first inclined surface. The second defined surface has a third inclined surface and a fourth inclined surface that is connected to the third inclined surface and is positioned on one side of the first direction relative to the third inclined surface. The first inclined surface is inclined in a direction that moves away from the second energy storage cell as it approaches the second inclined surface. The second inclined surface is inclined in a direction that moves away from the second energy storage cell as it approaches the first inclined surface. The third inclined surface is inclined in a direction that moves away from the first energy storage cell as it approaches the fourth inclined surface. The fourth inclined surface is inclined in a direction that moves away from the first energy storage cell as it approaches the third inclined surface. The plurality of first wound electrode bodies include a first electrode body and a second electrode body positioned on one side of the first direction relative to the first electrode body, The plurality of second wound electrode bodies include a third electrode body and a fourth electrode body positioned on one side of the third electrode body in the first direction, The first inclined surface is in contact with the first arc portion of the first electrode body. The second inclined surface is in contact with the first arc portion of the second electrode body. The third inclined surface is in contact with the second arc portion of the third electrode body. The energy storage device according to claim 1 or 2, wherein the fourth inclined surface is in contact with the second arc portion of the fourth electrode body.

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