Laminated battery

Abstract

Laminated battery (20), comprising: an electrode stack comprising a plurality of electrodes stacked together, each of the electrodes having a cuboid shape; and a laminate film (28A; 28A-1; 28B) covering and sealing the electrodes of the electrode stack, wherein the laminate film (28A; 28A-1; 28B) comprises a foil body (280) covering four surfaces of the electrode stack, a foil partition (284) disposed between two adjacent electrodes of the plurality of electrodes of the electrode stack, wherein the foil body (280) and the foil partition (284) define receiving portions (280B) each receiving a corresponding one of the electrodes, and Cover elements (282; 286) which are twice as many as the electrodes, wherein the cover elements (282; 286) cover two sides of each of the receiving sections (280B) and the two sides are not covered by the film body (280) or the film partition wall (284), and wherein each of the cover elements (282; 286) has a depressed portion comprising a bottom wall (282A; 286B) and four side walls (282B, 282C, 282D, 282E; 286B, 286C, 286D, 286E), an outer surface or an inner surface of the bottom wall (282A; 286B) of the depressed portion of each of the cover elements (282; 286) faces a side surface of a corresponding one of the electrodes, and outer surfaces of the side walls (282B, 282C, 282D, 282E; 286B, 286C, 286D, 286E) of the depressed portion are fused to the film body (280) or the film partition wall (284).

Description

BACKGROUND OF THE INVENTION1. Field of the InventionThe present invention relates to a laminated battery.2. Description of the Prior ArtA laminated battery in which an electrode including a positive electrode, a negative electrode, and a separator is covered and sealed by a laminate film was examined.For example, Japanese Patent Application JP 2013-058 498 A discloses a battery pack of a assembled battery including a plurality of cells each hermetically sealed by a laminate film, a case in which the cells are stacked, a positive electrode terminal and a negative electrode terminal of the assembled battery, a cover member, and fastening means. The positive electrode terminal and the negative electrode terminal of the assembled battery in which the cells are connected in parallel or in series are connected to a device outside the case. The cover member presses the top surface of the stacked cells stored in the case toward the inside of the case in a direction opposite to the stacking direction of the cells. The fastening means fixes the cover member to the housing at a position where a predetermined pressing force is applied. Furthermore, US 2022 / 0263206 A1 discloses a secondary battery having an electrode stack which is formed by stacking a sheet-shaped electrode element. The electrode stack is housed in an outer case, the outer case being a hollow laminated film outer case. This laminated case covers at least both end surfaces and a pair of side surfaces of the electrode stack facing each other in a stacking direction, and has an inner lid. This is disposed at an opening portion of the laminated film outer casing, and the inner lid has a protruding portion. This protruding part extends from a peripheral portion thereof to an inner side of the outer case, at least a part of the electrode stack is present in a region surrounded by the protruding part, and the peripheral portion of the inner lid and a part of the laminated outer case are joined to each other to seal the electrode stack in the outer case, the part overlapping the peripheral portion of the inner lid. Regarding the prior art, reference is also made to JP 2018-73 502 A, DE 11 2021 001 416 T5, DE 11 2011 104 018 T5 and JP 2023-135173 A.SUMMARY OF THE INVENTIONFor example, in order to achieve downsizing of a battery-equipped product, downsizing of the battery itself is required. For this reason, even in a battery in which an electrode stack having a plurality of stacked electrodes is covered by a laminate film, it is desirable that the overall size of the battery after the electrode stack is sealed by the laminate film be reduced by minimizing the volume of, for example, a space created by the presence of the laminate films.The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a laminated battery with high volumetric efficiency.Means for solving the above-described problem include the following aspects.(1) A laminated battery comprising: an electrode stack including a plurality of electrodes stacked together and having a rectangular parallelepiped shape; and a laminate film covering and sealing the electrodes of the electrode stack. The laminate film includes: a film body covering four surfaces of the electrode stack; a film partition wall disposed between two adjacent electrodes of the plurality of electrodes of the electrode stack; and covering members twice as many as the electrodes. The film body and the film partition define receiving portions each receiving a corresponding one of the electrodes. The cover members cover two sides of each of the receiving portions. The two sides are not covered by the film body or by the film separating wall. Each of the cover members has a recessed portion including a bottom wall and four side walls. An outer surface or an inner surface of the bottom wall of the recessed portion of each of the cover members faces a side surface of a corresponding electrode. Outer surfaces of the side walls of the recessed portion are fused to the film body or the film partition wall.(2) In the laminated battery according to aspect (1), the outer surface of the bottom wall of the recessed portion of each of the cover members faces the side surface of the corresponding electrode.(3) In the laminated battery according to aspect (2), the fused portions in which the outer surfaces of the side walls of the recessed portion of each of the cover members are fused to the film body or the film partition wall are folded inward in the recessed portion.According to the present invention, a laminated battery having high volumetric efficiency is provided.BRIEF DESCRIPTION OF THE DRAWINGSThe features and advantages, and technical and economic significance of exemplary embodiments of the invention will be described below with reference to the accompanying drawings, in which like numerals designate like elements, and wherein: FIG. 1A is a schematic perspective view illustrating a laminated sheet of a laminated battery according to a first embodiment of the present invention; FIG. 1B is a schematic perspective view illustrating a laminated sheet of a laminated battery according to a second embodiment of the present invention; FIG. 2 is a schematic side view illustrating a modification of the laminated battery according to the first embodiment of the present invention; FIG. 3 is a schematic plan view illustrating main parts of a vehicle; FIG. 4 is a schematic perspective view illustrating a battery module; FIG. 5 is a plan view illustrating the battery module with the top cover removed; and FIG. 6 is a schematic view illustrating a battery cell accommodated in the battery module as viewed in the thickness direction of the battery cell.DETAILED DESCRIPTION OF EMBODIMENTSHereinafter, embodiments will be described as examples according to the present invention. The descriptions and examples are for illustrating the embodiments and are not intended to limit the scope of the invention. With respect to the number ranges in phases described in this specification, an upper limit or a lower limit of a number range described in one phase may be replaced with an upper limit or a lower limit of another number range described in another phase. In addition, with respect to the numerical ranges described in this specification, an upper limit or a lower limit of a numerical range may be replaced with a value indicated in the embodiments.Laminated BatteryA laminated battery according to the embodiment of the present invention includes: an electrode stack including a plurality of electrodes stacked together and having a rectangular parallelepiped shape; and a laminate film covering and sealing the electrodes of the electrode stack. The laminate film includes: a film body covering four surfaces of the electrode stack; a film partition wall disposed between two adjacent electrodes of the plurality of electrodes of the electrode stack; and covering members twice as many as the electrodes. The film body and the film partition define receiving portions each receiving a corresponding one of the electrodes. The cover members cover two sides of each of the receiving portions. The two sides are not covered by the film body or by the film separating wall. Each of the cover members has a recessed portion including a bottom wall and four side walls. An outer surface or an inner surface of the bottom wall of the recessed portion of each of the cover members faces a side surface of a corresponding electrode. Outer surfaces of the side walls of the recessed portion are fused to the film body or the film partition wall.For example, in order to achieve downsizing of a battery-equipped product, downsizing of the battery itself is required. For this reason, even in a battery in which an electrode stack having a plurality of stacked electrodes is covered by a laminate film, it is required that the volume of, for example, a space created by covering the electrode stack by the laminate film is reduced. In other words, a reduction in the overall size of the battery including the laminate film is desired. A conventional laminated battery has a configuration in which, for example, each of the electrodes of an electrode stack is covered by a single sheet of a laminate film, and the electrodes each of which is covered by a single sheet of a laminate film are stacked together. In this case, each of the electrodes is sealed by a single sheet of the laminated film in the following manner: a single sheet of the laminated film is covered and wraps four surfaces of the corresponding electrode and both wrapping ends of the single sheet of the laminated film are fused together, and then excess portions of the laminated film on two side surfaces of the corresponding electrode which remain uncovered are folded inward and fused.On the other hand, the laminated battery according to the embodiments of the present invention has a configuration in which the film body covers the four surfaces of the electrode stack, the film partition wall is disposed between two adjacent electrodes of the plurality of electrodes of the electrode stack, and paired cover members, which are different from the film body and the film partition wall, respectively, cover the both sides (paired sides) of each of the accommodation portions defined by the film body and the film partition wall. Each of the accommodating portions accommodates an electrode. The cover elements are twice as many as the electrodes. The two sides are not covered either by the film body or by the film separating wall. Therefore, in the configuration of the embodiments of the present invention, surplus portions of the laminate film on the side surfaces of each of the electrodes of the electrode stack need not be folded inward and fused. This configuration reduces the overall length of the laminated battery in its width direction (the direction in which the both side surfaces of each of the electrodes face each other). Thus, the size of the laminated battery can be reduced. In addition, the number of the laminate films disposed between the electrodes stacked in this configuration is smaller than that in the conventional configuration in which each of the electrodes is individually sealed by the laminate film, i.e., each of the electrodes of the electrode stack is individually covered by the laminate film, and then the electrodes each covered by the laminate film are stacked together. In this respect as well, the size of the laminated battery can be reduced. As a result, the volumetric efficiency is improved and the energy density is thus increased.Hereinafter, the laminated battery according to the embodiments of the present invention will be described in detail by way of specific examples with reference to the accompanying drawings. The drawings referred to in the following description are only schematically illustrated, and the sizes and shapes of the components in the drawings are exaggerated for better understanding.First EmbodimentFIG. 1A is a schematic perspective view illustrating a laminated film of a laminated battery according to a first embodiment of the present invention. Note that in FIG. 1A, the illustration of an electrode stack with stacked electrodes is omitted, and only the laminate film (a film body, film partition walls, and covering members) covering and sealing the electrode stack is illustrated in order to facilitate understanding of a configuration of the laminate film, which is a feature of the present invention. Figure 1A shows the laminate film sealing the electrode stack including four electrodes stacked together.A laminate film 28A shown in FIG. 1A includes a film body 280, three film partition walls 284, and eight cover members 282. In the laminate film 28A illustrated in FIG. 1A, four receiving portions 280B are defined by the film body 280 and the three film partitions 284. As indicated by two-dot chain lines in FIG. 1A, the eight cover members 282 are fitted into the inner sides of the accommodating portions 280B defined by the film body 280 and the film partition walls 284. That is, a cover member 282 is fitted in each of both sides of a receiving portion 280B so that each of the receiving portions 280B is sealed. Then, an electrode (not shown) is accommodated in each of the four accommodation portions 280B.The film body 280 consists of a single film layer. The film body 280 is disposed so as to cover the four surfaces of the electrode stack (the electrode stacks including the four electrodes stacked in FIG. 1A ), and both ends of the film body 280 covering the electrode stack are fused together, thereby forming a fused body portion 280A.It is noted that the film body 280 illustrated in FIG. 1A is made up of a single film layer, but the film body 280 may be made up of two or more film layers. For example, the film body may be made of two films and have two fusion-bonded portions provided by fusing one end of a first film to one end of a second film and fusing the other end of the first film to the other end of the second film so that the film body is arranged to cover the four surfaces of the electrode stack.An inner space of the film body 280 is divided into four spaces by the three film partition walls 284, and the four spaces respectively provide the accommodating portions 280B. That is, in the laminate film 28A illustrated in FIG. 1A, each of the three film partitions 284 is disposed between any two adjacent electrodes of the four electrodes of the electrode stack (not illustrated). Each of the film partitions 284 is fused and attached to the film body 280 at a pair of fused partition portions 284A. In a state where the electrode stack including the four electrodes (not illustrated) is covered only by the film body 280 and the three film partition walls 284, two side surfaces (paired side surfaces) of each of the electrodes are exposed.The laminate film 28A includes the eight cover members 282. That is, the cover members 282 are twice as many as the electrodes. Each of the cover members 282 has a recessed shape defined by a bottom wall 282A and four side walls 282B, 282C, 282D, 282E. That is, each of the cover members 282 has a recessed portion including the bottom wall 282A and the four side walls 282B, 282C, 282D, 282E. The cover members 282 are respectively fitted into the inner sides of the accommodation portions 280B defined by the film body 280 and the film partition walls 284 so that the outer surfaces of the bottom walls 282A of the recessed portions face the side surfaces of the electrodes (so as to face the accommodation portions 280B). Thereby, the both side surfaces of each of the electrodes not covered by any one of the film body 280 and the film partition walls 284 are covered by the bottom walls 282A of the cover members 282 (more specifically, the outer surfaces of the bottom walls 282A of the recessed portions).In addition, the outer surfaces of the four recessed portion side walls 282B, 282C, 282D, 282E of each of the cover members 282 fitted into the inner sides of the accommodating portions 280B are in contact with the film body 280 or the film partition walls 284. The outer surfaces of the four side walls 282B, 282C, 282D, 282E of each recessed portion are fused to the film body 280 or the film partition walls 284 that are in contact with the outer surfaces, thereby providing fused cover portions. Thereby, the four electrodes of the electrode stack (not shown) are sealed in the individual spaces (i.e., the four accommodation portions 280B) within the laminate film 28A, respectively.In the laminated battery having this configuration in which the electrode stack including the four electrodes stacked together is sealed by the laminated film 28A illustrated in FIG. 1A, the entire length of the laminated battery in the width direction thereof is reduced. With this configuration, the number of sheets of the laminate film interposed between the electrodes stacked together is also reduced. This reduces the size of the laminated battery, improves the volumetric efficiency, and increases the energy density.Modification of the First EmbodimentIn the laminated battery according to the first embodiment of the present invention, the fused portions (i.e., fused cover portions) provided by fusing the outer surfaces of the side walls of the recessed portions of the cover members with the sheet body or the sheet partitions are preferably folded inward in the recessed portions of the cover members.FIG. 2 is a schematic side view illustrating a modification of the laminated battery according to the first embodiment of the present invention. FIG. 2 is the side view of the laminated battery as viewed in the width direction thereof (the direction in which the two side surfaces of each of the electrodes face each other, a Z direction of FIG. 2 ).The laminated battery illustrated in FIG. 2 is the laminated battery of FIG. 1A in which the electrode stack including the four electrodes stacked together is sealed by the laminated film 28A in a state in which the fused portions (i.e., fused cover portions) joined by fusing the outer surfaces of the four side walls 282B, 282C, 282D, 282E of the recessed portion of each of the cover members 282 to the film body 280 or the film partition walls 284 are folded inward in the recessed portions of the cover members 282.In a laminate film 28A- 1 illustrated in FIG. 2, the cover members 282 are fitted into the inner sides of the accommodating portions 280B defined by the film body 280 and the film partition walls 284. Then, the outer surfaces of the four side walls 282B, 282C, 282D, 282E of each of the cover members 282 are fused to the film body 280 or the film partition walls 284, thereby providing fused cover portions 285B, 285C, 285D, 285E. Then, each of the fused cover portions 285B, 285C, 285D, 285E is folded inward in the recessed portions of the cover members 282. In the modification shown in FIG. 2, the fused cover portions 285B, 285D are first inwardly folded in the recessed portions of the cover members 282, and then the fused cover portions 285C, 285E are inwardly folded in the recessed portions of the cover members 282, so that the fused cover portions 285B, 285D are partially covered from the outside by the fused cover portions 285C, 285E.Since the fused portions provided by fusing the outer surfaces of the side walls of the recessed portion of each of the cover members with the film body or the film partition walls are folded inward in the recessed portions of the cover members, the entire length of the laminated battery in its width direction (the direction in which the both side surfaces of each of the electrodes face each other, the Z direction of FIG. 2 ) is further reduced. This reduces the size of the laminated battery, improves volumetric efficiency, and increases energy density.Second EmbodimentFIG. 1B is a schematic perspective view illustrating a laminated film of a laminated battery according to a second embodiment of the present invention. Note that in FIG. 1B, the illustration of the electrode stack including the stacked electrodes is omitted, and only the laminate film (the film body, the film partition walls, and the covering members) covering and sealing the electrode stack is illustrated in order to facilitate understanding of a configuration of the laminate film that is the feature of the present invention. FIG. 1B shows the laminate film sealing the electrode stack including the four stacked electrodes.A laminate film 28B illustrated in FIG. 1B includes the film body 280, the three film partition walls 284, and eight cover members 286. In the laminate film 28B illustrated in FIG. 1B, the four receiving portions 280B are defined by the film body 280 and the three film partitions 284. As indicated by two-dot chain lines in FIG. 1B, the eight cover members 286 are fitted into the inner sides of the accommodating portions 280B defined by the film body 280 and the film partition walls 284. That is, a cover member 286 is fitted in each of both sides of a receiving portion 280B so that each of the receiving portions 280B is sealed. Then, an electrode (not shown) is accommodated in each of the four accommodation portions 280B.The film body 280 and the film partition walls 284 have the same configurations as those illustrated in FIG. 1A, and therefore, the description of these configurations will be omitted below.The laminate film 28B includes the eight cover members 286. That is, the cover members 286 are twice as many as the electrodes. Each of the cover members 286 has a recessed shape defined by a bottom wall 286A and four side walls 286B, 286C, 286D, 286E. That is, each of the cover members 286 has a recessed portion including the bottom wall 286A and the four side walls 286B, 286C, 286D, 286E. The cover members 286 are respectively fitted into the inner sides of the accommodation portions 280B defined by the film body 280 and the film partition walls 284 such that the inner surfaces of the bottom walls 286A of the recessed portions face the side surfaces of the electrodes (so as to face the accommodation portions 280B). As a result, the both side surfaces of each of the electrodes that are not covered by one of the film body 280 and the film partition walls 284 are covered by the bottom walls 286A of the cover members 286 (more specifically, the inner surfaces of the bottom walls 286A of the recessed portions).In addition, the outer surfaces of the four recessed portion side walls 286B, 286C, 286D, 286E of each of the cover members 286 fitted into the inner sides of the receiving portions 280B are in contact with the film body 280 or the film partition walls 284. The outer surfaces of the four side walls 286B, 286C, 286D, 286E of each recessed portion are fused to the film body 280 or the film partitions 284 that are in contact with the outer surfaces, thereby providing the fused cover portions. Thereby, the four electrodes of the electrode stack (not shown) are sealed in the individual spaces (i.e., the four accommodation portions 280B) within the laminate film 28B, respectively.In the laminated battery having this configuration in which the electrode stack including the four electrodes stacked together is sealed by the laminated film 28B illustrated in FIG. 1B, the entire length of the laminated battery in the width direction thereof is reduced. With this configuration, the number of sheets of the laminate film interposed between the electrodes stacked together is also reduced. This reduces the size of the laminated battery, improves volumetric efficiency, and increases energy density.Next, with reference to the accompanying drawings, a battery module, a battery pack, and a vehicle each including the laminated battery according to the above-described embodiments of the present invention will be described.Overall Configuration of Vehicle 100FIG. 3 is a schematic plan view illustrating the main parts of a vehicle 100 to which a battery pack 10 according to a present embodiment is attached. As illustrated in FIG. 3, the vehicle 100 is a battery electric vehicle (BEV) equipped with the battery pack 10 under a vehicle floor. Note that in the drawings, an arrow UP indicates an upward direction in the vehicle height direction, an arrow FR indicates a front side in the vehicle front-rear direction, and an arrow LH indicates a left side in the vehicle width direction. In the following description of the directions, "front" and "rear" refer to the front side and the rear side in the vehicle front-rear direction, respectively, "right" and "left" refer to the right side and the left side in the vehicle width direction, respectively, and "up" and "down" refer to the upper side and the lower side in the vehicle height direction, respectively, unless otherwise stated.For example, the vehicle 100 according to a present embodiment has a configuration in which a DC-DC converter 102, an electric compressor 104, and a PTC heater (PTC=Positive Temperature Coefficient) 106 are disposed in front of the battery pack 10 in the vehicle front-rear direction. An electric motor 108, a transmission 110, an inverter 112, and a charger 114 are disposed rearward of the battery pack 10 in the vehicle front-rear direction.DC power output from the battery pack 10 is supplied to the electric compressor 104, the PTC heater 106, the inverter 112, and others after a voltage of the DC power is regulated by the DC-DC converter 102. The power supply to the electric motor 108 via the inverter 112 rotates the rear wheels of the vehicle, thereby driving the vehicle 100 in motion.A charging port 116 is provided on the right side of the rear part of the vehicle 100. By connecting a charging plug of an external charger (not shown) to the charger 114 via the charging port 116, current is stored in the battery pack 10 via the charger 114.Note that the arrangements and structures of the components of the vehicle 100 are not limited to the configuration described above. The battery pack 10 may be used in, for example, an internal combustion hybrid electric vehicle (HEV) or a plug-in hybrid electric vehicle (PHEV) with an internal combustion engine. In the present embodiment, the vehicle is a rear wheel drive vehicle in which the electric motor 108 is disposed in a rear vehicle portion, but the configuration is not limited to that described above. The vehicle may be a front-wheel drive vehicle in which the electric motor 108 is disposed in a front vehicle portion. Alternatively, the vehicle may be a vehicle having a pair of electric motors 108, one located in a front vehicle section and the other located in a rear vehicle section. Alternatively, the vehicle may be a vehicle in which each of the wheels is provided with an in-wheel motor.The battery pack 10 includes a plurality of battery modules 11. Specifically, five units of the battery modules 11 are arranged on the right side of the vehicle 100 in the vehicle front-rear direction, and the remaining five units of the battery modules 11 are arranged on the left side of the vehicle 100 in the vehicle front-rear direction. The battery modules 11 are electrically connected to each other.FIG. 4 is a schematic perspective view illustrating the battery module 11. As illustrated in FIG. 4, the battery module 11 has a substantially rectangular parallelepiped shape and is disposed such that a longitudinal side thereof extends in the vehicle width direction. A case of the battery module 11 is made of an aluminum alloy. The case of the battery module 11 is manufactured by, for example, joining aluminum die-cast parts having an extruded profile of the aluminum alloy to both ends by laser welding.A pair of voltage terminals 12 and a connector 14 are provided at each of both ends of the battery module 11 in the vehicle width direction. A flexible printed circuit board (FPC) 22 described later is connected to the connector 14. A bus bar (not illustrated) is welded to each of both ends of the battery module 11 in the vehicle width direction.A length MW of the battery module 11 in the vehicle width direction is, for example, 350 mm to 600 mm. A length ML of the battery module 11 in the vehicle front-rear direction is, for example, 150 mm to 250 mm. A height MH of the battery module 11 in the vehicle height direction is, for example, 80 mm to 110 mm.FIG. 5 is a plan view illustrating the battery module 11 with a top cover removed therefrom. As illustrated in FIG. 5, a plurality of battery cells 20 are arranged and accommodated in the battery module 11. The present embodiment shows an example in which 24 units of the battery cells 20 are arranged in the vehicle front-rear direction and connected to each other.The FPC 22 is disposed on the battery cells 20. The FPC 22 has a strip shape with a long side thereof extending in the vehicle width direction. Each of the both end portions of the FPC 22 is provided with a thermistor 24. The thermistors 24 are not connected to the battery cells 20, but are pressed against the battery cells 20 by an upper cover of the battery module 11.One or more shock absorbing materials (not shown) are housed in the battery module 11. The shock absorbing material is, for example, an elastically deformable member having a thin plate shape, and is disposed between the battery cells 20 adjacent to each other, with the thickness direction of the shock absorbing material extending in the arrangement direction of the battery cells 20. The present embodiment shows an example in which the shock absorbing materials are disposed at both end portions of the battery module 11 in the longitudinal direction and at a central portion of the battery module 11 in the longitudinal direction.FIG. 6 is a schematic view illustrating the battery cell 20 accommodated in the battery module 11 as viewed in the thickness direction of the battery cell 20. As illustrated in FIG. 6, the battery cell 20 has a substantially rectangular plate shape, and an electrode (not illustrated) is accommodated in the battery cell 20. The electrode includes a positive electrode, a negative electrode, and a separator stacked together, and is sealed by the laminate film 28.The present embodiment shows an example in which the laminate film 28 embossed and having a sheet shape is folded and adhered to provide an electrode accommodation portion. One of the following embossed structures can be used: a single cap embossed structure in which a laminate film is embossed at one location; and a double cap embossed structure in which a laminate film is embossed at two locations. In the present embodiment, the single cap emboss structure is used with a draw depth in the range of about 8 mm to about 10 mm.Both upper ends of the battery cell 20 in the longitudinal direction are bent so that its outline shape is provided with corners. An upper end portion of the battery cell 20 in the height direction is bent, and a fixing tape 30 wraps around and extends along the upper end portion of the battery cell 20 in the longitudinal direction.Each of the both ends of the battery cell 20 in the longitudinal direction is provided with a terminal (tab) 26. The present embodiment shows an example in which each terminal 26 is disposed at a position below the center of the battery cell 20 in the height direction. Each terminal 26 is connected to a bus bar (not illustrated) by laser welding or the like.A length CW 1 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 mm to 900 mm, or 1000 mm or more. A length CW 2 of a region in which the electrode is accommodated is, for example, 500 mm to 520 mm, 600 mm to 700 mm, 700 mm to 800 mm, 800 to 900 mm, or 1000 mm or more. A height CH of the battery cell 20 is, for example, 80 mm to 110 mm or 110 mm to 140 mm. A thickness of the battery cell 20 is 5.0 mm to 7.0 mm, 7.0 mm to 9.0 mm, or 9.0 mm to 11.0 mm. A height TH of the terminal 26 is 40 mm to 50 mm, 50 mm to 60 mm, or 60 mm to 70 mm.

Claims

A laminated battery (20) comprising: an electrode stack comprising a plurality of electrodes stacked together, each of the electrodes having a rectangular parallelepiped shape; and a laminate film (28A; 28A-1; 28B) covering and sealing the electrodes of the electrode stack, wherein the laminate film (28A; 28A-1; 28B) comprises a film body (280) covering four surfaces of the electrode stack, a film partition wall (284) disposed between two adjacent electrodes of the plurality of electrodes of the electrode stack, wherein the film body (280) and the film partition wall (284) define accommodation portions (280B) each accommodating a corresponding one of the electrodes, and cover members (282; 286) twice as many as the electrodes, wherein the cover members (282; 282; 286) cover two sides of each of the receiving portions (280B), and the two sides are not covered by either the film body (280) or the film partition wall (284), and wherein each of the cover members (282; 286) has a recessed portion including a bottom wall (282A; 286B) and four side walls (282B, 282C, 282D, 282E; 286B, 286C, 286D, 286E), an outer surface or an inner surface of the bottom wall (282A; 286B) of the recessed portion of each of the cover members (282; 286) faces a side surface of a corresponding one of the electrodes, and outer surfaces of the side walls (282B, 282C, 282D, 282E; 286b, 286c, 286d, 286e) of the recessed portion are fused to the film body (280) or the film partition (284).The laminated battery (20) according to claim 1, wherein the outer surface of the recessed portion bottom wall (282A; 286B) of each of the cover members (282; 286) faces the side surface of the corresponding electrode.The laminated battery (20) according to claim 2, wherein fused portions (285B, 285C, 285D, 285E) in which the outer surfaces of the recessed portion side walls (282B, 282C, 282D, 282E; 286B, 286C, 286D, 286E) of each of the cover members (282; 286) are fused to the film body (280) or the film partition wall (284) are folded inward in the recessed portion.

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