Electricity storage device and method for manufacturing electricity storage device

Abstract

The present disclosure relates to a power storage device and a method of manufacturing the power storage device capable of avoiding power reduction due to cooling and temperature rise. A power storage device is provided with a power storage module and a heat exchanger which uses the power storage module as a heat exchange object. The power storage module and the heat exchanger are joined by an adhesive. The heat exchanger exchanges heat with an object to be subjected to heat exchange by means of a cold medium flowing through the main flow path and the auxiliary flow path. The heat exchanger includes a base member and an outer wall. The outer wall is provided on the base member. The main flow path is formed inside the base member. The sub-flow path is formed by a base member and an outer wall, and the outer wall is more easily deformed than the base member and the power storage module.

Description

Technical Field

[0001] The present disclosure relates to a power storage device and a method for manufacturing the power storage device. Background Art

[0002] For example, Japanese Patent Publication No. 2013-545219 discloses a heat exchanger that exchanges heat with a power storage module. The power storage module and the heat exchanger exchange heat in a contact area. Summary of the Invention

[0003] The heat exchanger disclosed in Japanese Patent Application Publication No. 2013-545219 includes an outer plate and an inner plate. A flow path is formed within the heat exchanger by the outer plate and the inner plate having a protrusion. The protrusion is formed so that it can be compressed by input from the outer plate.

[0004] With this structure, when the battery module is stacked on the heat exchanger, the outer plate deforms along with the protrusions, conforming to the surface shape of the battery module. This deformation increases the contact area between the outer plate and the battery module, resulting in efficient heat exchange.

[0005] However, because the outer plate deforms based on the deformation of the protrusions, it deforms vertically at the nodes, while the internodes remain flat and undeformed. Consequently, the outer plate cannot properly conform to the subtle shape of the heat exchange object. Consequently, a gap remains between the outer plate and the battery module. The cross-sectional area of ​​the coolant flow path decreases due to the gap, reducing cooling and heating efficiency.

[0006] The present disclosure has been made in view of the above-mentioned problems, and an object thereof is to provide a heat exchanger having a shape that conforms to the surface shape of an object to be heat exchanged, such as a power storage module.

[0007] The first embodiment of the present disclosure provides a power storage device comprising: a power storage module; and a heat exchanger having the power storage module as a heat exchange target. The power storage module and the heat exchanger are bonded together by an adhesive. The heat exchanger exchanges heat with the heat exchange target using a cold medium flowing through a main flow path and a secondary flow path. The heat exchanger includes a base member and an outer wall. The outer wall is provided on the base member. The main flow path is formed within the base member. The secondary flow path is formed by the base member and the outer wall. The outer wall is more easily deformed than the base member and the power storage module.

[0008] The linear expansion coefficient of the outer wall of the electricity storage device according to the first aspect of the present disclosure may be larger than that of the base member.

[0009] The yield stress of the outer wall of the electricity storage device according to the first aspect of the present disclosure may be smaller than that of the base member.

[0010] The elastic modulus of the outer wall of the electricity storage device according to the first aspect of the present disclosure may be smaller than that of the base member.

[0011] The manufacturing method of the power storage device of the second embodiment of the present disclosure comprises a coating process, a configuration process and a deformation process. The power storage device comprises: a power storage module, and a heat exchanger for cooling or heating the power storage module by a cold medium flowing in a main flow path and a secondary flow path. The heat exchanger comprises a base member and an outer wall. The outer wall is provided on the base member. The main flow path is formed inside the base member. The secondary flow path is formed by the base member and the outer wall. The outer wall is easier to deform than the base member and the power storage module. The coating process comprises a process of applying an adhesive to the surface of the outer surface of the outer wall opposite to the power storage module. The configuration process comprises a process of alternately stacking the power storage module and the heat exchanger in the first direction. The deformation process comprises a process of deforming the outer wall in a manner along the shape of the power storage module by causing a fluid to flow in the secondary flow path.

[0012] In the method for manufacturing a power storage device according to the second aspect of the present disclosure, the fluid may be at 200° C. or higher.

[0013] The foregoing and other objects, features, aspects and advantages of the present disclosure will become apparent from the following detailed description of the present disclosure when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is an exploded perspective view of the power storage device according to this embodiment.

[0015] Figure 2 yes Figure 1 Cross-sectional view of section II-II in FIG.

[0016] Figure 3 It is a cross-sectional view of the power storage module according to this embodiment.

[0017] Figure 4 This is a diagram showing an example of a coating step in the method for manufacturing a power storage device according to the present embodiment.

[0018] Figure 5 This is a diagram showing an example of an arrangement step in the method for manufacturing a power storage device according to the present embodiment.

[0019] Figure 6 This is a diagram showing an example of a deformation process in the method for manufacturing the power storage device according to the present embodiment. DETAILED DESCRIPTION

[0020] The embodiments of the present disclosure will be described with reference to the accompanying drawings. In the drawings referred to below, the same or corresponding components are denoted by the same reference numerals.

[0021] <Configuration of this embodiment>

[0022] Figure 1: is an exploded perspective view of the power storage device of this embodiment. Figure 1 , the stacking direction H indicates the stacking direction of the stacked body 20 described later. The width direction W indicates the width direction of the power storage device 1. Here, the stacking direction H is an example of the "first direction" in the present disclosure.

[0023] The power storage device 1 includes a housing case 10 and a stacked body 20. The housing case 10 houses the stacked body 20 therein and constrains the stacked body 20 in a stacking direction H.

[0024] The storage case 10 includes an upper cover 11 and a lower case 12. The upper cover 11 and the lower case 12 are arranged at intervals in the stacking direction H. The upper cover 11 and the lower case 12 are fastened in the stacking direction H by bolts or the like.

[0025] The lower case 12 is formed to open upward. It includes a lower plate 13a and a peripheral wall 13b. When viewed from a distance from the lower plate 13a in the stacking direction H, the lower plate 13a is rectangular. The peripheral wall 13b rises from the outer edge of the lower plate 13a. The upper cover 11 is formed to cover the opening of the lower case 12.

[0026] The stacked body 20 is housed in the housing case 10. Electrically insulating insulating films 15a and 15b are disposed between the housing case 10 and the stacked body 20. Thus, the housing case 10 and the stacked body 20 are insulated from each other.

[0027] The stack 20 includes a plurality of power storage modules 30, a main heat exchanger 100, and terminal heat exchangers 200a and 200b. The power storage modules 30 are stacked along a stacking direction H, sandwiching the main heat exchanger 100. In the stacking direction H, the terminal heat exchanger 200a is positioned at one end of the stacked power storage modules 30. The terminal heat exchanger 200b is positioned at the other end of the power storage modules 30. The power storage modules 30 are an example of a "heat exchange object" in the present disclosure. The main heat exchanger 100 and the terminal heat exchangers 200a and 200b are examples of a "heat exchanger" in the present disclosure.

[0028] Figure 2 yes Figure 1 The power storage module 30 is a bipolar battery, for example. When viewed from a distance from the power storage module 30 in the stacking direction H, the power storage module 30 has a rectangular shape. The power storage module 30 has main surfaces 30a and 30b aligned in the stacking direction H. The main surface 30a of the power storage module 30 faces the main heat exchanger 100 or the terminal heat exchanger 200a, and the main surface 30b of the power storage module 30 faces the main heat exchanger 100 or the terminal heat exchanger 200b.

[0029] Furthermore, conductive adhesive A is provided between the power storage module 30 and the main heat exchanger 100, between the power storage module 30 and the terminal heat exchanger 200a, and between the power storage module 30 and the terminal heat exchanger 200b. Adhesive A is not essential and may not be provided. Without adhesive A, the power storage module 30 is in contact with the main heat exchanger 100 or the terminal heat exchangers 200a and 200b.

[0030] The main heat exchanger 100 has electrical conductivity and electrically connects the power storage module 30 adjacent to the main heat exchanger 100 .

[0031] The main heat exchanger 100 has a flow path inside. The main heat exchanger 100 cools or heats the adjacent power storage module 30 using the cooling medium C flowing through the flow path 101. Furthermore, the flow path 101 includes a main flow path 102 and a secondary flow path 103. The secondary flow path 103 includes a first path 103a and a second path 103b. The structure of the main heat exchanger 100 is described in detail below.

[0032] The main heat exchanger 100 has a base member 110 , an outer wall 130 , and an outer wall 140 .

[0033] A main flow path 102 is formed within the base member 110. The main flow path 102 is formed of a plurality of flow paths. The base member 110 has a first plane 111 and a second plane 112. The first plane 111 and the second plane 112 are end surfaces of the base member 110 in the stacking direction H. Furthermore, when viewed from a position away from the first plane 111 and the second plane 112 in the stacking direction H, the first plane 111 and the second plane 112 are formed in a square shape. Furthermore, the first plane 111 includes an outer edge portion 111a, and the second plane 112 includes an outer edge portion 112a.

[0034] The outer wall 130 is provided on the first flat surface 111 of the base member 110 in the stacking direction H. The outer wall 130 includes a plate-shaped member 132 and a joining member 131 formed on the outer peripheral edge of the plate-shaped member 132 and formed in an annular shape.

[0035] The joining member 131 is formed on the first plane 111 and extends in an annular shape along an outer edge portion 111 a located at an end of the first plane 111 in the width direction W. The joining member 131 is joined to the base member 110 by welding, brazing, or the like.

[0036] The plate-shaped member 132 is arranged spaced apart from the first plane 111 in the stacking direction H. The plate-shaped member 132 is formed to conform to the main surface 30b of the power storage module 30. More specifically, the plate-shaped member 132 is formed to have a concave and convex shape along the main surface 30b in the stacking direction H. The plate-shaped member 132 has a main surface 132a. The main surface 132a is the surface facing the main surface 30b of the power storage module 30. Adhesive A may also be applied to the main surface 132a. The adhesive A is arranged to fill the gap between the main surface 30b and the main surface 132a.

[0037] The outer wall 140 is provided on the second flat surface 112 of the base member 110 in the stacking direction H. The outer wall 140 includes a plate-shaped member 142 and a joining member 141 formed in an annular shape and formed on the outer peripheral edge portion of the plate-shaped member 142 .

[0038] The joining member 141 is formed on the second plane 112 and extends in an annular shape along an outer edge portion 112 a located at an end of the second plane 112 in the width direction W. The joining member 141 is joined to the base member 110 by welding, brazing, or the like.

[0039] The plate-shaped member 142 is arranged spaced apart from the second plane 112 in the stacking direction H. The plate-shaped member 142 is formed to conform to the main surface 30a of the power storage module 30. More specifically, the plate-shaped member 142 is formed to have a concave and convex shape along the main surface 30a in the stacking direction H. The plate-shaped member 142 has a main surface 142a. The main surface 142a is the surface facing the main surface 30a of the power storage module 30. Adhesive A may also be applied to the main surface 142a. The adhesive A is arranged to fill the gap between the main surface 30a and the main surface 142a.

[0040] Terminal heat exchangers 200a and 200b have a similar structure to main heat exchanger 100. They each comprise a base member and a single outer wall. Specifically, while main heat exchanger 100 includes two outer walls 130 and 140, terminal heat exchangers 200a and 200b each have a single outer wall. Otherwise, the structure of terminal heat exchangers 200a and 200b is essentially the same as that of main heat exchanger 100.

[0041] The terminal heat exchanger 200a and the terminal heat exchanger 200b have electrical conductivity. Since the terminal heat exchanger 200b has substantially the same structure as the terminal heat exchanger 200a, the following description will focus on the structure of the terminal heat exchanger 200a.

[0042] The terminal heat exchanger 200 a includes a base member 210 and an outer wall 220 .

[0043] A main flow path 202 is formed inside the base member 210. The main flow path 202 is formed of a plurality of flow paths. The base member 210 has a first plane 211 and a second plane 212. The first plane 211 and the second plane 212 are end faces of the base member 110 in the stacking direction H, respectively.

[0044] Furthermore, the first plane 211 and the second plane 212 are formed into a square shape when viewed from a position away from the first plane 211 and the second plane 212 in the stacking direction H. The first plane 211 includes an outer edge portion 211 a, and the second plane 212 includes an outer edge portion 212 a.

[0045] The outer wall 220 is provided on the first flat surface 211 of the base member 210 in the stacking direction H. The outer wall 220 includes a plate-shaped member 222 and a joining member 221 formed in an annular shape and formed on the outer peripheral edge portion of the plate-shaped member 222 .

[0046] The joining member 221 is formed on the first plane 211 and extends in an annular shape along an outer edge portion 211 a located at an end of the first plane 211 in the width direction W. The joining member 221 is joined to the base member 210 by welding, brazing, or the like.

[0047] The plate-shaped member 222 is arranged spaced apart from the first plane 211 in the stacking direction H. The plate-shaped member 222 is formed to conform to the main surface 30a of the power storage module 30. More specifically, the plate-shaped member 222 is formed to have a concave and convex shape along the main surface 30a in the stacking direction H. The plate-shaped member 222 has a main surface 222a. The main surface 222a is the surface facing the main surface 30a of the power storage module 30. Adhesive A may also be applied to the main surface 222a. Adhesive A is applied to fill the gap between the main surface 30b and the main surface 222a.

[0048] The terminal heat exchanger 200a is arranged at one end of the stacked electricity storage modules 30 in the stacking direction H. The second plane 212 is adjacent to the insulating film 15a. The positive electrode terminal 2 is connected to the terminal heat exchanger 200a.

[0049] The terminal heat exchanger 200b is arranged at the other end of the stacked electricity storage modules 30 in the stacking direction H. The second plane 212 is adjacent to the insulating film 15b. The negative electrode terminal 3 is connected to the terminal heat exchanger 200b.

[0050] The positive electrode terminal 2 and the negative electrode terminal 3 each extend in the width direction W. By connecting the positive electrode terminal 2 and the negative electrode terminal 3 to external terminals, the power storage device 1 can be charged and discharged.

[0051] Figure 3: is a cross-sectional view of a power storage module according to this embodiment. The power storage module 30 is formed of an electrode stack 31 and a resin portion 32. The electrode stack 31 includes a plurality of unit cells 33. The unit cells 33 are stacked in a stacking direction H.

[0052] Each unit cell 33 includes a first current collector plate 34 , a first active material layer 35 , a separator 36 , a second active material layer 37 , and a second current collector plate 38 .

[0053] The first current collector plate 34 is made of, for example, aluminum. The first active material layer 35 is, for example, a positive electrode active material layer. The first active material layer 35 is formed on a first coated surface 34 a of the first current collector plate 34 . The first coated surface 34 a is the bottom surface of the first current collector plate 34 .

[0054] The second active material layer 37 is, for example, a negative electrode active material layer. The second active material layer 37 is formed on the second coating surface 38a of the second current collector plate 38. The second coating surface is the upper surface of the second current collector plate 38. The second current collector plate 38 is made of, for example, copper.

[0055] Separator 36 is disposed between first active material layer 35 and second active material layer 37. Separator 36 is formed, for example, in a sheet shape. Separator 36 comprises, for example, a polymer that absorbs and retains the electrolyte. Examples of materials constituting separator 36 include polypropylene (PP), polyethylene (PE), polyolefins, and polyesters.

[0056] In the unit cells 33 adjacent to each other in the stacking direction H, the first collector plate 34 of one unit cell 33 contacts the second collector plate 38 of the other unit cell. The electrode stack 31 is formed by the contacting first and second collector plates 34 and 38 .

[0057] An electrolyte L is sealed in a space formed by the current collector plates 34 and 38 and the resin portion 32 .

[0058] Furthermore, in the stacking direction H, the first collector plate 34 is exposed at one end of the electrode stack 31, and the second collector plate 38 is exposed at the other end of the electrode stack 31. In the stacking direction H, the first collector plate 34 and the second collector plate 38 exposed at the ends of the electrode stack 31 are referred to as end walls 39 and 40, respectively.

[0059] The end wall 39 has a main surface 30a. The main surface 30a is arranged on the other side of the first coating surface 34a in the stacking direction H. The end wall 40 has a main surface 30b. The main surface 30b is arranged on the other side of the second coating surface 38a in the stacking direction H.

[0060] The resin portion 32 is formed in an annular shape so as to surround the electrode stack 31 . The outer peripheral edge portions of the first current collector plate 34 , the second current collector plate 38 , and the separator 36 are embedded in the resin portion 32 .

[0061] Here, the main heat exchanger 100 and the terminal heat exchangers 200a and 200b are made of substantially the same material. Therefore, the characteristics of the material forming the outer walls 130 and 140 will be described mainly by comparing the material forming the main heat exchanger 100 with the material forming the base member 110 .

[0062] The linear expansion coefficient [1 / K] of the material forming the outer walls 130 and 140 of the main heat exchanger 100 may be larger than that of the material forming the base member 110. The linear expansion coefficient is measured in accordance with JIS Z 2285. Specifically, the linear expansion coefficient is calculated based on the relationship between the temperature change of the sample and the change in length of each sample.

[0063] The yield stress [MPa] of the material forming the outer walls 130 and 140 may be smaller than that of the material forming the base member 110. The yield stress is measured in accordance with JIS Z 2241. That is, the yield stress is calculated based on the relationship between the test force at the yield point and the cross-sectional area of ​​the specimen.

[0064] Young's modulus of the material forming the outer walls 130, 140 [N / mm 2 ] may be smaller than the material forming the base member 110. The Young's modulus is measured in accordance with JIS Z 2280. That is, the Young's modulus is calculated based on the relationship between stress and strain in the elastic region of the sample.

[0065] Bending rigidity of outer walls 130, 140 [N·mm 2 ] can also be smaller than the base member 110. Furthermore, the bending stiffness is calculated based on the Young's modulus [N / mm 2 ] and the section moment of inertia of the outer walls 130 and 140 [mm 4 ]Determined value.

[0066] The relationship between the base member 210 and the outer wall 220 in the terminal heat exchangers 200 a and 200 b also has the above-described structure similar to the relationship between the base member 110 and the outer walls 130 and 140 in the main heat exchanger 100 .

[0067] For example, when stainless steel such as SUS304 or steel plates such as SGCC are used for the base members 110 and 210, aluminum such as A5052-O, 5083-O, or 6063-T5, which have a higher linear expansion coefficient and lower yield stress than these materials, can be used for the outer walls 130 and 140. Alternatively, when aluminum is used for the base members 110 and 210, a resin material having a higher linear expansion coefficient and lower yield stress than these materials can be used for the outer walls 130 and 140.

[0068] In the above embodiment, the main heat exchanger 100 and the terminal heat exchangers 200a and 200b exchange heat with the power storage module 30. For example, the power storage device 1 mounted on a vehicle cools or heats the power storage module 30 by flowing the cooling medium C through the flow path 101 of the main heat exchanger 100.

[0069] In the above-described embodiment, for example, the plate-like member 132 is formed in a concavo-convex shape along the stacking direction H of the main surface 30 b.

[0070] By adopting such a structure, the contact area between the power storage module 30 and the plate-shaped member 132 can be increased compared to a case where a gap exists between the power storage module 30 and the plate-shaped member 132. Thus, the power storage device 1 including a highly efficient heat exchanger can be provided.

[0071] The main heat exchanger 100 and other components of the power storage device 1 mounted on a vehicle must be strong enough to resist deformation due to external forces. In the above-described embodiment, for example, the base member 110 is formed from a member that is less susceptible to deformation than the outer walls 130 and 140. The base member 110 particularly functions to suppress deformation of the main heat exchanger 100 caused by external forces in the width direction W.

[0072] By adopting this structure, the bending stiffness of outer walls 130 and 140 can be reduced. Specifically, thin plate-shaped members 132 and 142 can be used. As a result, the heat capacity of plate-shaped members 132 and 142 is reduced, shortening the heat transfer path from the cooling medium C to the power storage module 30. This allows for a power storage device 1 with excellent control over thermal responsiveness.

[0073] Furthermore, with this configuration, when an external load is applied to the main heat exchanger 100, the base member 110 serves as the core portion, thereby suppressing deformation of the main heat exchanger 100. Furthermore, when the yield stress of the material forming the base member 110 is greater than that of the outer walls 130 and 140, or when the Young's modulus of the material forming the base member 110 is higher than that of the outer walls 130 and 140, the main heat exchanger 100 can be made smaller and thinner.

[0074] In the electricity storage device manufactured as described above, for example, the thickness of the adhesive A between the main surface 30b and the plate-shaped member 142 can be made thinner and more uniform. Consequently, when the manufactured electricity storage device 1 is mounted on a vehicle or the like, for example, and the cooling medium C is supplied to the main heat exchanger 100, the heat exchange efficiency of the main heat exchanger 100 can be improved compared to a case where the adhesive A is thicker and more unevenly thickened. Furthermore, the electricity storage module 30 can be evenly cooled or heated by the main heat exchanger 100.

[0075] In the power storage device manufactured as described above, for example, the plate-shaped member 132 is deformed to conform to the shape of the main surface 30b. Therefore, compared to power storage devices in which the plate-shaped member 132 does not conform to the shape of the main surface 30b but rather a gap is created between the plate-shaped member 132 and the main surface 30b, the power storage device 1 of this embodiment can reduce the amount of adhesive A used, while also providing a power storage device with a thinner adhesive A, enabling highly efficient heat exchange. Furthermore, the power storage device 1 of this embodiment can increase the cross-sectional area of ​​the flow path for the cooling medium C. Consequently, when the power storage device 1 is mounted on a vehicle and the cooling medium C is supplied to the main heat exchanger 100, the pressure loss of the cooling medium C flowing through the flow path 101 can be reduced, thereby improving the vehicle's power.

[0076] <Manufacturing Method of This Embodiment>

[0077] Next, an example of a method for manufacturing the power storage device 1 will be described. The power storage device 1 includes a coating step, a placement step, and a deformation step in this order. Figures 4 to 6 The details of each process are described.

[0078] Figure 4 This diagram illustrates an example of a coating process. In the coating process, adhesive A is applied to main heat exchanger 100, terminal heat exchanger 200a, and terminal heat exchanger 200b. More specifically, adhesive A is applied to main surfaces 132a and 142a of plate-shaped members 132 and 142 of main heat exchanger 100. Furthermore, adhesive A is applied to main surface 222a of plate-shaped member 222 of terminal heat exchangers 200a and 200b.

[0079] Figure 5 This diagram illustrates an example of the arrangement process. In the arrangement process, a stack 20A is formed. Specifically, the power storage modules 30 are stacked in a stacking direction H. Furthermore, a main heat exchanger 100 is positioned between the power storage modules 30. A terminal heat exchanger 200a is positioned at one end of the stacked power storage modules 30 in the stacking direction H. A terminal heat exchanger 200b is positioned at the other end of the stacked power storage modules 30 in the stacking direction H.

[0080] Next, the stacked body 20A is housed in the housing case 10. An insulating film 15 is placed between the stacked body 20A and the housing case 10. The stacked body 20A is restrained in the stacking direction H by the upper cover 11 and the lower plate 13a forming the housing case 10.

[0081] Figure 6This diagram illustrates an example of a deformation process. In the deformation process, the plate-shaped member 132 is deformed into a shape that conforms to the main surface 30b of the power storage module 30. Furthermore, the plate-shaped member 142 is deformed into a shape that conforms to the main surface 30a of the power storage module 30. The same applies to the terminal heat exchangers 200a and 200b.

[0082] More specifically, a high-pressure fluid W flows through the first path 103a of the main heat exchanger 100. As a result, the pressure in the first path 103a becomes higher than the external air pressure. Since the stack 20A is constrained by the housing 10 in the stacking direction H, the plate-like member 132 is deformed along the shape of the main surface 30b due to the fluid W. Similarly, by allowing the high-pressure fluid W to flow through the second path 103b of the main heat exchanger 100, the plate-like member 142 is deformed along the shape of the main body 30a. When the high-pressure fluid W is caused to flow to the secondary flow path 103 having the first path 103a and the second path 103b, it is preferable to also cause the fluid W to flow to the main flow path 102 at the same time. This is to suppress the load applied to the main flow path 102 due to the pressure difference.

[0083] The same applies to the deformation of the plate-shaped member 222 in the terminal heat exchangers 200a and 200b.

[0084] Furthermore, in the deformation process, a plurality of heat exchangers may be formed simultaneously, or each heat exchanger may be formed sequentially. For example, this process may also serve as a leak test for the heat exchangers included in the power storage device 1 .

[0085] In the above embodiment, the main heat exchanger 100 is disposed adjacent to the power storage module 30. Here, for example, the plate-shaped member 132 forming the main heat exchanger 100 is more easily deformed than the base member 110. The fact that the plate-shaped member 132 is more easily deformed than the base member 110 refers to formability based on a comparison of the linear expansion coefficient, yield stress, Young's modulus, or moment of inertia of the area.

[0086] Furthermore, the plate-shaped members 132 and 142 forming the main heat exchanger 100 are more easily deformed than the electricity storage module 30. Here, the plate-shaped members 132 and 142 being more easily deformed than the electricity storage module 30 means that, even when a load is applied to the electricity storage module 30 by the plate-shaped members 132 and 142 due to the flow of high-pressure fluid W through the first path 103a and the second path 103b of the stack 20A, the plate-shaped members 132 and 142 can be deformed along the main surfaces 30a and 30b without damaging the electricity storage module 30.

[0087] Damage to the power storage module 30 refers to cracks or breakage in the first active material layer 35 , the separator 36 , or the second active material layer 37 , wrinkles in the resin portion 32 , or leakage of the electrolyte in the power storage module 30 .

[0088] In this embodiment, the high-pressure fluid W flows through the secondary flow path 103 , and thus the plate-shaped members 132 and 142 can be deformed into shapes along the main surfaces 30 a and 30 b without damaging the electricity storage module 30 .

[0089] The high-pressure fluid W is a fluid having a water pressure greater than the output pressure of the vehicle-mounted pump (5 MPa) and not more than 20 MPa.

[0090] Alternatively, the fluid W can be high temperature. By allowing the high-temperature fluid W to flow within the flow path 101, thermal expansion occurs, allowing the plate-shaped member 132 to deform along the shape of the main surface 30b. Furthermore, the plate-shaped member 132 formed of metal exhibits excellent ductility at high temperatures. Therefore, compared to deformation processes using a low-temperature fluid W, the possibility of brittle fracture during deformation processes using a high-temperature fluid W can be suppressed.

[0091] Here, the high-temperature fluid W is, for example, 100°C or higher and 310°C or lower. This is because the maximum temperature of the cooling medium C used by the vehicle-mounted power storage device 1 to cool the power storage module 30 is 100°C. In particular, when aluminum such as A5052-O, 5083-O, or 6063-T5 is used for the outer walls 130 and 140, the high-temperature fluid W, specifically oil at a temperature of 200°C or higher, is preferably used.

[0092] Furthermore, the joined portions between the base member 110 and the outer walls 130 , 140 are sufficiently joined and do not peel off when the outer walls 130 , 140 are deformed.

[0093] In the above embodiment, the adhesive A is applied to the plate-shaped members 132 and 142 .

[0094] For example, in a power storage device where the main surface 30b of the power storage module 30 and the main surface 132a of the main heat exchanger 100 cannot be aligned in planarity, a gap forms between the main surfaces. Closing this gap requires applying a large amount of adhesive A. According to the embodiments of the present disclosure, the plate-shaped member 132 deforms along the main surface 30b, thereby reducing the amount of adhesive A used. This reduced amount reduces the electrical resistance caused by the adhesive A. Furthermore, it reduces the size increase of the power storage device 1.

[0095] Without adhesive A, gaps may occur due to springback after the load caused by the fluid W is removed, or contraction after the plate-like member 132 returns to room temperature. When adhesive A is applied, adhesive A is cured while the plate-like member 132 is deformed along the main surface 30 b. This allows the shape of the plate-like member 132 to be maintained even after the load caused by the fluid W is removed and the plate-like member 132 returns to room temperature.

[0096] While the embodiments of the present disclosure have been described, they should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims, and all modifications within the meaning and scope of the equivalents of the claims are intended to be encompassed.

Claims

1. A power storage device comprising: a power storage module; and a heat exchanger that uses the power storage module as a heat exchange object. The power storage module and the heat exchanger are bonded together by an adhesive. The heat exchanger exchanges heat with the heat exchange object through the cold medium flowing in the main flow path and the secondary flow path. The heat exchanger comprises a base member and an outer wall, The outer wall is provided on the base member, The main flow path is formed inside the base member, The secondary flow path is formed by the base member and the outer wall, The outer wall is more easily deformed than the base member and the electricity storage module. 2 . The power storage device according to claim 1 , wherein the outer wall has a larger linear expansion coefficient than the base member. The power storage device according to claim 1 , wherein the outer wall has a yield stress smaller than that of the base member. The power storage device according to claim 1 , wherein the outer wall has a smaller elastic modulus than that of the base member.

5. A method for manufacturing an electricity storage device, comprising a coating step, a placement step, and a deformation step. The power storage device includes: a power storage module; and a heat exchanger for cooling or heating the power storage module using a cooling medium flowing through a main flow path and a secondary flow path. The heat exchanger comprises a base member and an outer wall, The outer wall is provided on the base member, The main flow path is formed inside the base member, The secondary flow path is formed by the base member and the outer wall, The outer wall is more easily deformed than the base member and the electricity storage module. The coating step includes applying an adhesive to a surface of the outer surface of the outer wall that faces the power storage module. The arranging step includes the step of alternately stacking the power storage modules and the heat exchangers in a first direction. The deforming step includes deforming the outer wall to conform to the shape of the electricity storage module by causing a fluid to flow through the secondary flow path. 6 . The method for manufacturing an electricity storage device according to claim 5 , wherein the fluid has a temperature of 200° C. or higher.

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