Laminated battery

Abstract

A laminated battery is provided with: an electrode laminate in which a plurality of rectangular parallelepiped-shaped electrode bodies are laminated; and a laminated film that covers and encloses the electrode body, the laminated film having: a film main body that covers four surfaces of the electrode laminate; a membrane partition portion interposed between two adjacent electrode bodies among the plurality of electrode bodies; and cover members that cover each of the remaining two side surfaces of a housing section that is formed by the film main body and the film partition section and that houses each of the electrode bodies, the number of the cover members being twice the number of the electrode bodies, the cover members having a recessed section that is composed of one bottom surface and four wall surfaces, the outer side surface or the inner side surface of the bottom surface facing the side surfaces of the electrode bodies, and the outer side surface or the inner side surface of the bottom surface facing the side surfaces of the electrode bodies. The outer side surface of the wall surface is welded to the film body or the film partition wall portion.

Description

Technical Field

[0001] The present invention relates to a laminated battery. Background Art

[0002] There has been discussed a technique of a laminated battery in which an electrode body having a positive electrode, a negative electrode, and a separator is covered with a laminated film and sealed therein.

[0003] For example, Japanese Unexamined Patent Application Publication No. 2013-058498 discloses a battery pack of a combined battery, which includes: a plurality of single cells, each of which is hermetically sealed with a laminated film; a case that stores the stacked single cells; a positive terminal and a negative terminal of the combined battery, which are connected in parallel or in series to the single cells and connected to the outside of the case; a lid member that presses from the uppermost surface of the stack of the plurality of single cells stored in the case in a direction opposite to the stacking direction of the single cells against the inside of the case; and a fixing mechanism that fixes the lid member to the case at a position of a specified pressing force. Summary of the Invention

[0004] Heretofore, due to miniaturization of products equipped with batteries and other reasons, miniaturization of the battery itself has been required. Therefore, in a battery in which an electrode laminate in which a plurality of electrode bodies are stacked is covered with a laminated film, it is also desired to minimize the volume such as the space generated due to the presence of the laminated film and to reduce the overall size after the laminated film is sealed.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide a laminated battery having a high volume efficiency.

[0006] Solutions for solving the above problems include the following aspects.

[0007] <1> A laminated battery, comprising: an electrode laminate in which a plurality of rectangular parallelepiped electrode bodies are stacked; and a laminated film that covers and seals each electrode body in the electrode laminate, the laminated film having: a film main body that covers four surfaces of the electrode laminate; a film partition portion that is interposed between two adjacent electrode bodies among the plurality of electrode bodies in the electrode laminate; and lid members that respectively cover two side surfaces in a housing portion that is formed by the film main body and the film partition portion and that houses one electrode body each, and the number of the lid members is twice the number of the electrode bodies, each lid member having a concave-shaped portion formed by one bottom surface and four wall surfaces, an outer side surface or an inner side surface of the bottom surface of the concave-shaped portion facing a side surface of the electrode body, and an outer side surface of the wall surface of the concave-shaped portion being welded to the film main body or the film partition portion.

[0008] <2>The laminated battery according to <1>, wherein, in the lid member, an outer side surface of the concave-shaped portion in the bottom surface faces a side surface of the electrode body.

[0009] <3>The laminated battery according to <2>, wherein an outer side surface of the concave-shaped portion in the wall surface of the lid member, and a welded portion formed by welding the film main body or the film partition portion is folded toward the inside of the concave-shaped portion.

[0010] According to the present invention, a laminated battery having a high volume efficiency can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Hereinafter, with reference to the drawings, features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described. In the drawings, the same reference numerals denote the same elements, and:

[0012] Figure 1A is a schematic perspective view of a laminated film in a laminated battery according to an embodiment of the present invention.

[0013] Figure 1B is a schematic perspective view of a laminated film in a laminated battery according to another embodiment of the present invention.

[0014] Figure 2 is a schematic side view of a modified example of a laminated battery according to an embodiment of the present invention.

[0015] Figure 3 is a schematic top view of a main part of a vehicle.

[0016] Figure 4 is a schematic perspective view of a battery module.

[0017] Figure 5 is a top view of a state where an upper lid of the battery module is removed.

[0018] Figure 6 is a schematic view of a battery cell accommodated in the battery module as viewed in the thickness direction. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] Hereinafter, an embodiment as an example of the present invention will be described. These descriptions and examples are for illustrative purposes and do not limit the scope of the invention.

[0020] In the numerical ranges described stepwise in this specification, an upper limit value or a lower limit value described in one numerical range can be replaced with an upper limit value or a lower limit value of another stepwise described numerical range. And, in the numerical ranges described in this specification, the upper limit value or the lower limit value of the numerical range can be replaced with the value shown in the examples.

[0021] <Laminated battery>

[0022] The laminated battery according to an embodiment of the present invention includes: an electrode laminate in which a plurality of rectangular parallelepiped electrode bodies are laminated; and a laminated film that covers and encloses each electrode body in the electrode laminate.

[0023] The laminated film has: a film main body that covers four surfaces of the electrode laminate; a film partition portion that is interposed between two adjacent electrode bodies among the plurality of electrode bodies in the electrode laminate; and cover members that respectively cover two side surfaces that are not covered by any of the film main body and the film partition portion in the accommodation portions formed by the film main body and the film partition portion and each accommodate one electrode body, and the number thereof is twice that of the electrode bodies.

[0024] The cover member has a concave-shaped portion formed by one bottom surface and four wall surfaces. The outer side surface or the inner side surface of the concave-shaped portion in the bottom surface faces the side surface of the electrode body, and the outer side surface of the concave-shaped portion in the wall surface is welded to the film main body or the film partition portion.

[0025] In a battery, due to miniaturization of the product on which the battery is mounted and other reasons, miniaturization of the battery itself is required. Therefore, in a battery in which an electrode laminate in which a plurality of electrode bodies are laminated is covered with a laminated film, reduction in volume of space and the like generated by covering with the laminated film is also required, that is, miniaturization of the whole including the laminated film is desired.

[0026] In addition, in a conventional laminated battery, for example, each electrode body in the electrode laminate is configured to be covered with only one laminated film, and the electrode bodies covered with the laminated film are laminated. In this case, the electrode body is enclosed in the following manner: after one laminated film is wound to cover four surfaces of the electrode body and the ends of the laminated film are welded to each other, the remaining two side surfaces of the electrode body are further welded in a manner of forming a woven shape with excess laminated film on the side surface side.

[0027] In contrast, the laminated battery according to an embodiment of the present invention is configured such that: the four surfaces of the electrode laminate are covered by the film main body, the film partition portion is interposed between two adjacent electrode bodies among the plurality of electrode bodies in the electrode laminate, and two side surfaces (a pair of side surfaces) that are not covered by the film main body and the film partition portion in the accommodation portions formed by the film main body and the film partition portion and each accommodate one electrode body are respectively covered with a pair of cover members different from the film main body and the film partition portion, that is, cover members having a number twice that of the electrode bodies.

[0028] Therefore, there is no need to weld the excess laminated film in a woven manner on the side surfaces of each electrode body in the electrode laminate. As an overall laminated battery, the length in the width direction (the direction in which two side surfaces of each electrode body face each other) can be shortened. Thus, the size of the laminated battery can be reduced.

[0029] Moreover, compared with the structure in which each electrode body is separately enclosed by a laminated film, that is, each electrode body in the electrode laminate is separately covered by a laminated film and the electrode bodies covered by the laminated film are laminated, the number of laminated films between the laminated electrode bodies can be reduced. In this regard, the size of the laminated battery can also be reduced.

[0030] As a result, the volumetric efficiency can be improved and the energy density can be increased.

[0031] Next, the laminated battery according to the embodiment of the present invention will be described in detail with reference to legends and specific examples.

[0032] In addition, the following figures are schematic representations. For ease of understanding, the sizes and shapes of each part are appropriately exaggerated.

[0033] (First Mode)

[0034] Figure 1A is a schematic perspective view of the laminated film in the laminated battery according to the embodiment of the present invention. In addition, in Figure 1A , in order to easily understand the structure of the laminated film which is a feature of the present invention, the electrode laminate on which the electrode bodies are laminated is omitted, and only the laminated film (film main body, film partition portion, and cover member) that covers and encloses the electrode laminate is shown. In addition, in Figure 1A , the laminated film enclosing the electrode laminate on which 4 electrode bodies are laminated is shown.

[0035] Figure 1A The laminated film 28A shown in Figure 1A has a film main body 280, 3 film partition portions 284, and 8 cover members 282. In the laminated film 28A shown in Figure 1A , 4 accommodating portions 280B are formed by the film main body 280 and 3 film partition portions 284. As shown by the dashed line in

[0036] , 8 cover members 282 are embedded in such a manner as to enter the inside of the accommodating portion 280B formed by the film main body 280 and the film partition portion 284. That is, one cover member 282 is embedded on each of the two side surfaces of one accommodating portion 280B to seal the accommodating portion 280B. Moreover, one electrode body (not shown) is accommodated in each of the 4 accommodating portions 280B. Figure 1AFour surfaces of the electrode laminate having four electrode bodies laminated therein), and in addition, the ends of the film main body 280 are welded to each other to form a main body welded portion 280A.

[0037] In addition, Figure 1A shows a structure in which the film main body 280 is composed of only one film, but the film main body 280 may also be composed of two or more films. For example, it may be configured such that one ends of two films are welded to each other, and the other ends are welded to each other, to form a film main body having two main body welded portions, and this film main body is arranged to cover four surfaces of the electrode laminate.

[0038] The space inside the film main body 280 is divided into four spaces by three film partition portions 284, and each of the four spaces forms a receiving portion 280B. That is, in Figure 1A the laminated film 28A shown, the three film partition portions 284 are respectively interposed between four electrode bodies (not shown) constituting the electrode laminate. The film partition portions 284 are fixed by being welded to the film main body 280 at a pair of partition welded portions 284A respectively.

[0039] In a state where an electrode laminate (not shown) composed of four electrode bodies is covered only by the film main body 280 and the three film partition portions 284, two side surfaces (a pair of side surfaces) of each electrode body are in an exposed state.

[0040] The laminated film 28A has eight lid members 282, which is twice the number of electrode bodies. Each lid member 282 has a concave shape composed of one bottom surface 282A and four wall surfaces 282B, 282C, 282D, and 282E. That is, each lid member 282 has a concave shape portion including one bottom surface 282A and four wall surfaces 282B, 282C, 282D, and 282E. Further, the lid member 282 is inserted into the inside of the receiving portion 280B formed by the film main body 280 and the film partition portion 284 in such a manner that the outer side surface of the concave shape portion in the bottom surface 282A faces the side surface of the electrode body (that is, in a manner facing the receiving portion 280B side). Thus, the two side surfaces of the electrode body that are not covered by the film main body 280 and the film partition portion 284 are respectively covered by the bottom surface 282A of the lid member 282 (more specifically, the outer side surface of the concave shape portion in the bottom surface 282A).

[0041] Further, the outer sides of the concave-shaped portions on the four wall surfaces 282B, 282C, 282D, and 282E of the lid member 282 embedded inside the accommodation portion 280B are all in contact with the film main body 280 or the film partition portion 284. The outer sides of the concave-shaped portions on the four wall surfaces 282B, 282C, 282D, and 282E are welded to the film main body 280 or the film partition portion 284 in contact with each surface to form a lid welding portion. Thus, the four electrode bodies (not shown) constituting the electrode laminate are respectively sealed in different spaces (i.e., the four accommodation portions 280B) inside the laminated film 28A.

[0042] In the laminated battery in which the electrode laminate having four electrode bodies laminated is sealed with the laminated film 28A having this structure Figure 1A as shown, as a whole laminated battery, the length in the width direction can be shortened. Also, the number of laminated films between the laminated electrode bodies can be reduced. As a result, the size of the laminated battery can be reduced, the volumetric efficiency can be improved, and the energy density can be increased.

[0043] · Modification Example of the First Embodiment

[0044] In the laminated battery according to the embodiment of the present invention, the welding portion (i.e., the lid welding portion) formed by welding the outer side of the concave-shaped portion on the wall surface of the lid member to the film main body or the film partition portion is preferably folded toward the inside of the concave-shaped portion of the lid member.

[0045] Figure 2 is a schematic side view showing a modification example of the laminated battery according to the embodiment of the present invention. Figure 2 is a side view of the laminated battery as viewed from the width direction (the direction in which two side surfaces of the electrode body face each other, Figure 2 the Z direction in

[0046] Figure 2 In the laminated battery as shown, in the laminated battery in which the electrode laminate having four electrode bodies laminated is sealed with the laminated film 28A as shown Figure 1A the welding portion (i.e., the lid welding portion) formed by welding the outer side of the concave-shaped portion on the four wall surfaces 282B, 282C, 282D, and 282E of the lid member 282 to the film main body 280 or the film partition portion 284 is folded toward the inside of the concave-shaped portion of the lid member 282.

[0047] In Figure 2In the laminated film 28A-1 shown, the lid member 282 is embedded inside the accommodation portion 280B formed by the film main body 280 and the film partition portion 284. Moreover, the outer sides of the four wall surfaces 282B, 282C, 282D, and 282E of the lid member 282 are welded to the film main body 280 or the film partition portion 284 to form lid welding portions 285B, 285C, 285D, and 285E. Moreover, the lid welding portions 285B, 285C, 285D, and 285E are respectively folded toward the inside in the concave-shaped portion of the lid member 282. In Figure 2 the manner shown, first, the lid welding portions 285B and 285D are folded toward the inside in the concave-shaped portion of the lid member 282, and then, the lid welding portions 285C and 285E are folded toward the inside in the concave-shaped portion of the lid member 282 so as to cover a part of the lid welding portions 285B and 285D from the outside.

[0048] By configuring the welding portion formed by welding the outer side of the concave-shaped portion in the wall surface of the lid member to the film main body or the film partition portion to be folded toward the inside in the concave-shaped portion of the lid member, as the laminated battery as a whole, it is possible to further shorten the length in the width direction (the direction in which two sides in the electrode body face each other, Figure 2 the Z direction in

[0049] (Second mode)

[0050] Figure 1B is a schematic perspective view of a laminated film in a laminated battery according to another embodiment of the present invention. In addition, in Figure 1B order to easily understand the structure of the laminated film which is a feature of the present invention, the electrode laminate in which the electrode body is laminated is omitted, and only the laminated film (film main body, film partition portion, and lid member) that covers and seals the electrode laminate is shown. In addition, in Figure 1B is shown a laminated film that seals an electrode laminate in which four electrode bodies are laminated.

[0051] Figure 1B The laminated film 28B shown has a film main body 280, three film partition portions 284, and eight lid members 286. In Figure 1B the laminated film 28B shown, four accommodation portions 280B are formed by the film main body 280 and the three film partition portions 284. As Figure 1B shown by the one-dot chain line in, eight lid members 286 are embedded so as to enter the inside of the accommodation portions 280B formed by the film main body 280 and the film partition portion 284. That is, the accommodation portions 280B are sealed by embedding one lid member 286 on each of the two side surfaces on both sides of one accommodation portion 280B. Moreover, one electrode body (not shown) is accommodated in each of the four accommodation portions 280B.

[0052] The membrane main body 280 and the membrane partition portion 284 have the same structure as the Figure 1A structure shown, and the description thereof is omitted here.

[0053] The laminated film 28B has eight lid members 286, which is twice the number of the electrode bodies. Each lid member 286 has a concave shape formed by one bottom surface 286A and four wall surfaces 286B, 286C, 286D, and 286E. That is, each lid member 286 has a concave-shaped portion including one bottom surface 286A and four wall surfaces 286B, 286C, 286D, and 286E. Moreover, the lid member 286 is inserted into the inside of the accommodating portion 280B formed by the membrane main body 280 and the membrane partition portion 284 in such a manner that the inner side surface of the concave-shaped portion in the bottom surface 286A faces the side surface of the electrode body (that is, in a manner facing the accommodating portion 280B side). Thus, the two side surfaces of the electrode body that are not covered by the membrane main body 280 and the membrane partition portion 284 are respectively covered by the bottom surface 286A of the lid member 286 (more specifically, the inner side surface of the concave-shaped portion in the bottom surface 286A).

[0054] In addition, the outer side surfaces of the concave-shaped portions in the four wall surfaces 286B, 286C, 286D, and 286E of the lid member 286 inserted into the inside of the accommodating portion 280B are in contact with the membrane main body 280 or the membrane partition portion 284. The outer side surfaces of the concave-shaped portions in the four wall surfaces 286B, 286C, 286D, and 286E are welded to the membrane main body 280 or the membrane partition portion 284 in contact with each surface to form lid welding portions. Thus, the four electrode bodies (not shown) constituting the electrode laminate are respectively sealed in different spaces (that is, the four accommodating portions 280B) inside the laminated film 28B.

[0055] In a laminated battery in which an electrode laminate in which four electrode bodies are laminated is sealed with the laminated film 28B having this structure, as the laminated battery as a whole, the length in the width direction can be shortened. Moreover, the number of laminated films between the laminated electrode bodies can be reduced. As a result, the size of the laminated battery can be reduced, the volume efficiency can be improved, and the energy density can be increased. Figure 1B Next, a battery module, a battery pack, and a vehicle having the laminated battery according to the embodiment of the present invention will be described with reference to the drawings.

[0056]

[0057] (Overall Structure of Vehicle 100)

[0058] Figure 3 Figure 3 is a schematic top view showing the main part of a vehicle 100 to which the battery pack 10 according to the embodiment is applied. As Figure 3As shown, vehicle 100 is a battery electric vehicle (BEV) with a battery pack 10 mounted under the floor. Additionally, the arrows UP, FR, and LH in each figure respectively represent the upper side in the vehicle's up-down direction, the front side in the vehicle's front-rear direction, and the left side in the vehicle's width direction. When using the directions of front, rear, left, right, up, and down for explanation, unless otherwise specified, they represent the front and rear in the vehicle's front-rear direction, the left and right in the vehicle's width direction, and the up and down in the vehicle's up-down direction.

[0059] As an example, in vehicle 100 of the present embodiment, a DC / DC converter 102, an electric compressor 104, and a PTC (Positive Temperature Coefficient) heater 106 are arranged on the front side of the vehicle relative to the battery pack 10. And a motor 108, a gearbox 110, an inverter 112, and a charger 114 are arranged on the rear side of the vehicle relative to the battery pack 10.

[0060] The direct current output from the battery pack 10 is adjusted in voltage by the DC / DC converter 102 and then supplied to the electric compressor 104, the PTC heater 106, the inverter 112, etc. And the vehicle 100 travels by supplying power to the motor 108 via the inverter 112 to rotate the rear wheels.

[0061] A charging port 116 is provided at the right side portion of the rear of the vehicle 100. By connecting a charging plug of an external charging device (not shown) to the charging port 116, power can be stored in the battery pack 10 via the charger 114.

[0062] In addition, the configuration and structure of each component constituting the vehicle 100 are not limited to the above structure. For example, the battery pack 10 can also be applied to a hybrid vehicle (HV) equipped with an engine or a plug-in hybrid electric vehicle (PHEV). And in the present embodiment, the vehicle is a rear-wheel drive vehicle with the motor 108 mounted on the rear of the vehicle, but it is not limited to this. It can also be a front-wheel drive vehicle with the motor 108 mounted on the front of the vehicle, or a pair of motors 108 can be mounted on the front and rear of the vehicle. Furthermore, it can also be a vehicle with in-wheel motors provided on each wheel.

[0063] Here, the battery pack 10 is configured to include a plurality of battery modules 11. In the present embodiment, as an example, 10 battery modules 11 are provided. Specifically, 5 battery modules 11 are arranged in the vehicle's front-rear direction along the right side of the vehicle 100, and 5 battery modules 11 are arranged in the vehicle's front-rear direction along the left side of the vehicle 100. And each battery module 11 is electrically connected.

[0064] Figure 4 is a schematic perspective view of the battery module 11. As Figure 4 shown, the battery module 11 is formed in a substantially rectangular parallelepiped shape with the vehicle width direction as the length direction. Moreover, the housing of the battery module 11 is formed of aluminum alloy. For example, by laser welding or the like, aluminum die-castings are joined to both end portions of an extruded profile of aluminum alloy, thereby forming the housing of the battery module 11.

[0065] A pair of voltage terminals 12 and connectors 14 are respectively provided at both end portions in the vehicle width direction of the battery module 11. A flexible printed circuit board 22 described later is connected to the connector 14. Moreover, bus bars (not shown) are welded to both end portions in the vehicle width direction of the battery module 11.

[0066] The length MW in the vehicle width direction of the battery module 11 is, for example, 350 mm to 600 mm, the length ML in the vehicle front-rear direction is, for example, 150 mm to 250 mm, and the height MH in the vehicle up-down direction is, for example, 80 mm to 110 mm.

[0067] Figure 5 is a top view of the state in which the upper cover of the battery module 11 is removed. As Figure 5 shown, a plurality of battery cells 20 are accommodated in the battery module 11 in an arranged state. In the present embodiment, as an example, 24 battery cells 20 are arranged in the vehicle front-rear direction and bonded to each other.

[0068] A flexible printed circuit (FPC) 22 is disposed on the battery cell 20. The flexible printed circuit board 22 is formed in a strip shape with the vehicle width direction as the length direction, and thermistors 24 are respectively provided at both end portions of the flexible printed circuit board 22. The thermistor 24 has the following structure: It is not bonded to the battery cell 20 and is pressed against the battery cell 20 side by the upper cover of the battery module 11.

[0069] Moreover, one or more buffer materials (not shown) are accommodated in the battery module 11. For example, the buffer material is a thin plate-like member capable of elastic deformation and is disposed between adjacent battery cells 20 with the arrangement direction of the battery cells 20 as the thickness direction. In the present embodiment, as an example, buffer materials are respectively disposed at both end portions in the length direction and the central portion in the length direction of the battery module 11.

[0070] Figure 6 is a schematic view of the battery cell 20 accommodated in the battery module 11 as viewed from the thickness direction. As Figure 6 shown, the battery cell 20 is formed in a substantially rectangular plate shape, and an electrode body (not shown) is accommodated therein. The electrode body is constituted by laminating a positive electrode, a negative electrode, and a separator, and is encapsulated by a laminated film 28.

[0071] In the present embodiment, as an example, the accommodation portion for the electrode body is formed by folding and bonding a sheet-like laminated film 28 that has been compression-molded. In addition, two structures can be adopted: a single-cup compression-molding structure with one compression-molding location and a double-cup compression-molding structure with two compression-molding locations. However, in the present embodiment, a single-cup compression-molding structure with a drawing depth of about 8 mm to 10 mm is adopted.

[0072] The upper ends of both ends in the longitudinal direction of the battery cell 20 are bent, and the corners form the outer shape. Moreover, the upper end portion of the battery cell 20 is bent, and a fixing band 30 is wound around the upper end portion of the battery cell 20 along the longitudinal direction.

[0073] Here, terminals (tabs) 26 are provided at both ends in the longitudinal direction of the battery cell 20. In the present embodiment, as an example, the terminals 26 are provided at positions offset downward from the center in the vertical direction of the battery cell 20. The terminals 26 are joined to a bus bar (not shown) by laser welding or the like.

[0074] The length CW1 of the battery cell 20 in the vehicle width direction is, for example, 530 mm to 600 mm, 600 mm to 700 mm, 700 mm to 800 mm, 800 to 900 mm, 1000 mm or more. The length CW2 of the region accommodating the electrode body is, for example, 500 mm to 520 mm, 600 mm to 700 mm, 700 mm to 800 mm, 800 to 900 mm, 1000 mm or more. The height CH of the battery cell 20 is, for example, 80 mm to 110 mm, 110 mm to 140 mm. Moreover, the thickness of the battery cell 20 is 5.0 mm to 7.0 mm, 7.0 mm to 9.0 mm, 9.0 mm to 11.0 mm, and the height TH of the terminals 26 is 40 mm to 50 mm, 50 mm to 60 mm, 60 mm to 70 mm.

Claims

1. A laminated battery, characterized in that have: an electrode stack including a plurality of rectangular parallelepiped electrode bodies stacked together; and a laminate film covering and sealing each electrode body in the electrode stack, The laminate film comprises: a membrane body, which covers four surfaces of the electrode stack; a membrane partition portion, which is interposed between two adjacent electrode bodies among the plurality of electrode bodies in the electrode stack; and a cover member, which respectively covers two side surfaces of a receiving portion that are not covered by any one of the membrane body and the membrane partition portion, wherein the receiving portion is formed by the membrane body and the membrane partition portion and each receives one electrode body, and the number of the cover members is twice that of the electrode bodies. The cover member has a concave portion consisting of a bottom surface and four wall surfaces, wherein the outer side surface or the inner side surface of the concave portion in the bottom surface is opposite to the side surface of the electrode body, and the outer side surface of the concave portion in the wall surface is welded to the membrane body or the membrane partition wall portion.

2. The laminated battery according to claim 1, characterized in that In the cover member, the outer side surface of the concave portion in the bottom surface faces the side surface of the electrode body.

3. The laminated battery according to claim 2, characterized in that A welded portion formed by welding the outer side surface of the concave portion in the wall surface of the cover member to the film body or the film partition wall portion is folded toward the inside of the concave portion.

Images