Battery

Abstract

To provide a battery in which liquid junction of an electrolyte portion is suppressed and furthermore the number of components is reduced.SOLUTION: A battery comprises an exterior material, a battery main body housed in the exterior material, and an electrolyte portion housed in the exterior material and being in contact with the battery main body. The battery main body includes a first cell, a current collector, and a second cell in this order in a thickness direction. The exterior material has an outer peripheral portion spaced apart from the first cell and the second cell in a plane direction orthogonal to the thickness direction. The electrolyte portion has fluidity at 25°C. The current collector extends from between the first cell and the second cell to the outer peripheral portion.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to batteries. [Background technology]

[0002] A battery including a current collector, a first cell, a first current collector, a second cell, a second current collector, an electrolyte portion, a sealing layer, and an exterior material is known (see Patent Document 1 below). In the battery described in Patent Document 1, the first current collector, the first cell, the current collector, the second cell, and the second current collector are arranged in this order in the thickness direction. The electrolyte portion has fluidity. The electrolyte portion is located between the first current collector and the current collector and is impregnated into the first cell. The electrolyte portion is also located between the second current collector and the current collector and is impregnated into the second cell. The sealing layer prevents the electrolyte portion from communicating between the current collector and the first current collector and between the current collector and the second current collector, respectively, thereby preventing a liquid junction caused by mixing of the electrolyte portion in contact with the first cell and the electrolyte portion in contact with the second cell. The exterior material houses the current collector, the first cell, the first current collector, the second cell, the second current collector, the electrolyte portion, and the sealing layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2019-175778 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for a battery that reduces the number of parts while suppressing liquid junctions in the electrolyte portion.

[0005] One object of the present disclosure is to provide a battery that reduces the number of parts while suppressing liquid junctions in the electrolyte portion. [Means for solving the problem]

[0006] A battery according to the present disclosure includes an exterior material, a battery body housed in the exterior material, and an electrolyte part housed in the exterior material and in contact with the battery body. The battery body includes a first cell, a current collector, and a second cell, arranged in that order in the thickness direction. The exterior material has an outer periphery that is spaced apart from the first cell and the second cell in a planar direction perpendicular to the thickness direction. The electrolyte part has fluidity at 25°C. The current collector extends from between the first cell and the second cell to the outer periphery. [Effects of the Invention]

[0007] In a battery according to the present disclosure, the number of parts is reduced while suppressing liquid junctions in the electrolyte portion. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view of a battery according to the present disclosure. [Figure 2] FIG. 2 is a cross-sectional view of the battery shown in FIG. 1 taken along line XX. [Figure 3] FIG. 3 is a cross-sectional view of the battery shown in FIG. 1 taken along line YY. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Outline of implementation] A battery according to the present disclosure includes an exterior material, a battery body housed in the exterior material, and an electrolyte part housed in the exterior material and in contact with the battery body. The battery body includes a first cell, a current collector, and a second cell, arranged in that order in the thickness direction. The exterior material has an outer periphery that is spaced apart from the first cell and the second cell in a planar direction perpendicular to the thickness direction. The electrolyte part has fluidity at 25°C. The current collector extends from between the first cell and the second cell to the outer periphery.

[0010] In the battery described in Patent Document 1, the sealing layer prevents the electrolyte portions located on both sides of the current collector in the thickness direction from communicating with each other. On the other hand, the battery according to the present disclosure does not include a sealing layer, and the current collector extending from between the first and second cells to the outer periphery prevents the electrolyte portions located on both sides of the current collector in the thickness direction from communicating with each other. This prevents liquid junctions in the electrolyte portions. As a result, this battery reduces the number of parts while preventing liquid junctions in the electrolyte portions.

[0011] In the battery, the exterior material is a laminate of two films, and includes a laminate portion where the two films are pressure-bonded at the outer periphery. The outer edge of the current collector may be sandwiched between the outer periphery. In this battery, liquid junction in the electrolyte portion can be more reliably suppressed.

[0012] In the battery, the film contains a thermoplastic resin, and the outer periphery is a fused portion of the thermoplastic resin. In this battery, liquid junction in the electrolyte portion can be more reliably suppressed.

[0013] In the battery, the battery body may further include a first current collector located on the opposite side of the current collector from the first cell, and a second current collector located on the opposite side of the current collector from the second cell. The first cell may include a first positive electrode active material layer in contact with the first current collector and a first negative electrode active material layer in contact with the current collector. The second cell may include a second positive electrode active material layer in contact with the current collector and a second negative electrode active material layer in contact with the second current collector. The first current collector may include an end face flush with an end face of the first positive electrode active material layer. The second current collector may include an end face flush with an end face of the second negative electrode active material layer.

[0014] In the battery, the first cell may further include a first separator located between the first positive electrode active material layer and the first negative electrode active material layer. The second cell may further include a second separator located between the second positive electrode active material layer and the second negative electrode active material layer. The outer peripheral portion of the first separator may protrude outward from the first positive electrode active material layer or the first negative electrode active material layer in the planar direction. The outer peripheral portion of the second separator may protrude outward from the second positive electrode active material layer or the second negative electrode active material layer in the planar direction. In this battery, a liquid junction in the electrolyte portion of the first cell and a liquid junction in the electrolyte portion of the first cell can be reliably suppressed.

[0015] The battery may further include a first connection terminal electrically connected to the first current collector, the first connection terminal penetrating the outer periphery of the exterior material, and a second connection terminal electrically connected to the second current collector, the second connection terminal penetrating the outer periphery of the exterior material.

[0016] [Specific examples of embodiments] Specific embodiments of the battery of the present disclosure will be described with reference to Figures 1 to 3. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and their description will not be repeated. Figure 1 is a plan view of a battery according to the present disclosure. Figure 2 is a cross-sectional view of the battery shown in Figure 1 taken along line XX. Figure 3 is a cross-sectional view of the battery shown in Figure 1 taken along line YY.

[0017] [Basic configuration of battery 1] The battery 1 extends along a plane P. The battery 1 has a sheet shape. The battery 1 has a rectangular shape when viewed in a thickness direction TD. The thickness direction TD is perpendicular to the plane P. The battery 1 includes an exterior material 2, a battery body 3, and an electrolyte portion 4. On the other hand, a battery including the sealing layer described in Patent Document 1 is not suitable for the present disclosure.

[0018] [Exterior material 2] The exterior material 2 is the main portion of the outer shape of the battery 1 when viewed in the thickness direction TD. Specifically, the exterior material 2 has a rectangular shape. The exterior material 2 is a packaging material (packaging bag). The exterior material 2 has an outer peripheral portion 21 and a central portion 22. When viewed in the thickness direction TD, the outer peripheral portion 21 includes an outer edge 24 of the exterior material 2. When viewed in the thickness direction TD, the outer peripheral portion 21 has a rectangular frame shape. The outer edge 24 has a first side 241, a second side 242, and two sides 243 and 244. The first side 241 is along the first straight line L1. The second side 242 faces the first side 241. The two sides 243 and 244 connect the first side 241 and the second side 242, respectively. The central portion 22 is located inside the outer peripheral portion 21 when viewed in the thickness direction TD. The planar direction PD is perpendicular to the thickness direction TD.

[0019] The packaging material 2 includes a laminated portion 23 in which two films 2A, 2B are pressure-bonded at the outer periphery 21. In other words, the outer periphery 21 of the packaging material 2 is the laminated portion 23. The film 2A includes a resin layer 203A and a metal foil 204A, which are arranged in this order in the thickness direction TD. The film 2A is sometimes referred to as a laminate film. The resin layer 203A forms the inner surface of the film 2A. The resin layer 203A faces toward the inside of the packaging material 2 in the central portion 22. The resin layer 203A is located on the inner side of the film 2A. The metal foil 204A forms the outer surface of the film 2A. The metal foil 204A faces toward the outside. The metal foil 204A contacts the outer surface of the resin layer 203A. As shown by the imaginary lines in FIG. 2, the film 2A may further include a second resin layer 205A. The second resin layer 205A is in contact with the outer surface of the metal foil 204A.

[0020] The resin layer 203A may be made of a thermoplastic resin. In other words, the film 2A includes a thermoplastic resin. The thermoplastic resin may be a polyolefin resin or a polyamide resin. The polyolefin resin may be polypropylene, polyethylene, or an ethylene-propylene copolymer. The polyamide resin may be nylon. The thermoplastic resin may preferably be a polyolefin resin, and more preferably polypropylene. The metal foil 204A may be made of aluminum, stainless steel, or nickel. The metal foil 204A may preferably be made of aluminum. The second resin layer 205A may be made of the thermoplastic resin described above, and preferably nylon.

[0021] The thickness of the resin layer 203A is 6 μm or more, preferably 14 μm or more, and 80 μm or less, preferably 56 μm or less. If the thickness of the resin layer 203A is equal to or greater than the above-mentioned lower limit, the outer peripheral portion 321 of the current collector 32 (described later) can be securely sandwiched and fixed. If the thickness of the resin layer 203A is equal to or less than the above-mentioned upper limit, the thickness of the laminated portion 23 can be prevented from becoming excessively thick. The thickness of the metal foil 204A is 20 μm or more and 40 μm or less. The thickness of the second resin layer 205A is 12 μm or more and 25 μm or less.

[0022] Film 2B has the same layer structure and size as film 2A. That is, film 2B includes resin layer 203B and metal foil 204B, in that order in the thickness direction TD. In packaging material 2, metal foil 204A, resin layer 203A, resin layer 203B, and metal foil 204B are arranged in this order in the thickness direction TD. Film 2B contains a thermoplastic resin. Resin layer 203B is fused to resin layer 203A in outer periphery 21. Resin layer 203B is not fused to resin layer 203A in central portion 22, and is disposed at a distance from resin layer 203A in the thickness direction TD. In the present disclosure, resin layers 203A and 203B are heat-fused portions in outer periphery 21. The boundary between resin layers 203A and 203B in outer periphery 21 may or may not be visible in cross-sectional observation. The metal foil 204B is located on the opposite side of the resin layer 203A from the resin layer 203B. The film 2B may further include a second resin layer 205B. The second resin layer 205A, the metal foil 204A, the resin layer 203A, the resin layer 203B, the metal foil 204B, and the second resin layer 205B are arranged in this order in the thickness direction TD. The thickness of the outer circumferential portion 21 is the total thickness of the two films 2A and 2B. The thickness of the outer circumferential portion 21 is 76 μm or more and 290 μm or less.

[0023] [Battery body 3] The battery body 3 is housed in an exterior packaging material 2. The battery body 3 includes a first cell 31, a current collector 32, and a second cell 33, arranged in this order in the thickness direction TD. The first cell 31, the current collector 32, and the second cell 33 are lined up in this order in the thickness direction TD. The battery body 3 further includes a first current collector 34 and a second current collector 35. In the battery body 3, the first current collector 34, the first cell 31, the current collector 32, the second cell 33, and the second current collector 35 are lined up in this order in the thickness direction TD.

[0024] <Current collector 32> The current collector 32 is located in the central portion 22 of the battery 1. The current collector 32 extends along the plane P. The current collector 32 has a foil (sheet) shape. The current collector 32 has a first main surface 32A and a second main surface 32B. The first main surface 32A faces the film 2A. The second main surface 32B is disposed at a distance from the first main surface 32A in the thickness direction TD. The second main surface 32B faces the film 2B. The current collector 32 has an outer circumferential edge 321. The outer circumferential edge 321 has a substantially rectangular shape. The outer circumferential edge 321 is shared by both the first main surface 32A and the second main surface 32B. Examples of materials for the current collector 32 include conductive inorganic materials. Examples of inorganic materials include metals and conductive carbon. Examples of metals include at least one selected from the group consisting of aluminum, titanium, gold, copper, platinum, chromium, and nickel. The metal may include an alloy. Examples of the alloy include stainless steel. Examples of the conductive carbon include acetylene black, carbon black, carbon fiber, and graphite. The conductive carbon is sometimes referred to as a conductive additive. The current collector 32 may be single-layered or multi-layered.

[0025] When the current collector 32 is a multi-layer structure, the current collector 32 includes a main layer and two surface layers (not shown). The material of the main layer includes the metal described above. The two surface layers contact the first and second main surfaces of the main layer, respectively. The second main surface is located on the side of the main layer opposite the first main surface. The surface layer includes conductive carbon and a binder. Examples of binders include polyvinylidene fluoride, polytetrafluoroethylene, styrene-butadiene rubber, carboxymethyl cellulose, and polyacrylic acid. The thickness of the current collector 32 is 15 μm or more and 50 μm or less. The thickness of the main layer is 10 μm or more and 40 μm or less. The thickness of the surface layer is 5 μm or more and 30 μm or less.

[0026] <First current collector 34> The first current collector 34 is located in the central portion 22 of the battery 1. The first current collector 34 is located on the opposite side of the current collector 32 from the first cell 31. The first current collector 34 overlaps the central portion 22 of the film 2A of the exterior packaging material 2 when viewed in the thickness direction. The first current collector 34 is in contact with the inner surface of the central portion 22 of the film 2A. Specifically, the first current collector 34 is joined to the inner surface of the central portion 22 of the film 2A. The first current collector 34 extends along the plane P. The first current collector 34 has an end surface 341. The layer structure and thickness of the first current collector 34 may be the same as the layer structure and thickness of the current collector 32, respectively.

[0027] <Second current collector 35> The second current collector 35 is located in the central portion 22 of the battery 1. The second current collector 35 is located on the opposite side of the current collector 32 when viewed from the second cell 33. The second current collector 35 overlaps the central portion 22 of the film 2B of the exterior packaging 2 when viewed in the thickness direction. The second current collector 35 contacts the inner surface of the central portion 22 of the film 2B. Specifically, the second current collector 35 is joined to the inner surface of the central portion 22 of the film 2B. The second current collector 35 extends along the plane P. The second current collector 35 has an end surface 351. The layer structure and thickness of the second current collector 35 may be the same as the layer structure and thickness of the current collector 32, respectively.

[0028] <First cell 31> The first cell 31 overlaps the central portion 22 of the exterior packaging material 2 when viewed in the thickness direction. The first cell 31 is disposed between the current collector 32 and the film 2A. More specifically, the first cell 31 is located between the current collector 32 and the first current collector 34. The first cell 31 includes a first positive electrode active material layer 311, a first negative electrode active material layer 312, and a first separator 313.

[0029] The first positive electrode active material layer 311 is in contact with the first current collector 34. Specifically, the first positive electrode active material layer 311 is in contact with the surface of the first current collector 34 opposite the film 2A. The first positive electrode active material layer 311 has an end surface 3111. The first positive electrode active material layer 311 extends along a plane P. Examples of materials for the first positive electrode active material layer include lithium compounds, nickel compounds, lead compounds, and sodium compounds. Examples of lithium compounds include lithium nickel cobalt manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium iron phosphate, lithium cobalt phosphate, lithium manganese phosphate, and lithium vanadium phosphate. Examples of nickel compounds include nickel oxyhydroxide. Examples of lead compounds include lead oxide. Examples of sodium compounds include sodium manganate, sodium nickelate, and sodium chromate. The thickness of the first positive electrode active material layer 311 is 1 μm or more and 200 μm or less.

[0030] The first negative electrode active material layer 312 is located between the current collector 32 and the first positive electrode active material layer 311. The first negative electrode active material layer 312 is in contact with the current collector 32. The first negative electrode active material layer 312 is in contact with the first main surface 32A of the current collector 32. Specifically, the first negative electrode active material layer 312 is bonded to the first main surface 32A of the current collector 32. The first negative electrode active material layer 312 faces the first positive electrode active material layer 311. The first negative electrode active material layer 312 is disposed with a gap between it and the first positive electrode active material layer 311 in the thickness direction TD. The first negative electrode active material layer 312 extends along the plane P. Examples of materials for the first negative electrode active material layer 312 include carbon, tin alloys, silicon-containing alloys, lithium titanate, lithium, lithium-aluminum alloys, metal hydrides (hydrogen storage alloys), zinc, cadmium, and lead. Examples of carbon include hard carbon, soft carbon, and graphite. The thickness of the first negative electrode active material layer 312 is 1 μm or more and 200 μm or less.

[0031] The first separator 313 is positioned between the first positive electrode active material layer 311 and the first negative electrode active material layer 312. The first separator 313 is disposed with a gap between the first positive electrode active material layer 311 and the first negative electrode active material layer 312. Although not shown, the first separator 313 may be in contact with the first positive electrode active material layer 311 and the first negative electrode active material layer 312. The first separator 313 extends along a plane P. The first separator 313 has an outer peripheral portion 3131 and a central portion 3132. The central portion 3132 is positioned inside the outer peripheral portion 3131. The first separator 313 is a porous material, a nonwoven fabric, or a woven fabric. The porous material may be a resin or a ceramic. Examples of the resin include a polyolefin resin, a polyester resin, and a cellulose resin. Examples of the polyolefin resin include polyethylene and polypropylene. Examples of the polyester resin include polyethylene terephthalate. An example of the cellulose resin is methyl cellulose. The thickness of first separator 313 is 1 μm or more and 50 μm or less.

[0032] <Second Cell 33> The second cell 33 overlaps the central portion 22 of the exterior packaging material 2 when viewed in the thickness direction. The second cell 33 is located on the opposite side of the current collector 32 from the first cell 31. The second cell 33 is disposed between the current collector 32 and the film 2B. More specifically, the second cell 33 is located between the current collector 32 and the second current collector 35. The second cell 33 includes a second positive electrode active material layer 331, a second negative electrode active material layer 332, and a second separator 333.

[0033] The second positive electrode active material layer 331 is in contact with the current collector 32. Specifically, the second positive electrode active material layer 331 is in contact with the second main surface 32B of the current collector 32. The second positive electrode active material layer 331 is bonded to the second main surface 32B of the current collector 32. The second positive electrode active material layer 331 is located between the current collector 32 and the film 2B. The second positive electrode active material layer 331 extends along the plane P. The material and thickness of the second positive electrode active material layer 331 are the same as those of the first positive electrode active material layer 311, respectively.

[0034] The second negative electrode active material layer 332 is located between the second positive electrode active material layer 331 and the second current collector 35. The second negative electrode active material layer 332 is in contact with the second current collector 35. Specifically, the second negative electrode active material layer 332 is bonded to the second current collector 35. The second negative electrode active material layer 332 faces the second positive electrode active material layer 331. The second negative electrode active material layer 332 is disposed at an interval from the second positive electrode active material layer 331 in the thickness direction TD. The second negative electrode active material layer 332 extends along a plane P. The second negative electrode active material layer 332 has an end surface 3321. The material and thickness of the second negative electrode active material layer 332 are the same as those of the first negative electrode active material layer 312, respectively.

[0035] The second separator 333 is located between the second positive electrode active material layer 331 and the second negative electrode active material layer 332. The second separator 333 is disposed with a gap between the second positive electrode active material layer 331 and the second negative electrode active material layer 332. Although not shown, the second separator 333 may be in contact with the second positive electrode active material layer 331 and the second negative electrode active material layer 332. The second separator 333 extends along a plane P. The second separator 333 has an outer peripheral portion 3331 and a central portion 3332. The central portion 3332 is located inside the outer peripheral portion 3331. The material and thickness of the second separator 333 are the same as those of the first separator 313.

[0036] [Electrolyte section 4] The electrolyte section 4 is housed in the exterior material 2. The electrolyte section 4 is in contact with the battery body 3. Specifically, the electrolyte section 4 is present between the first positive electrode active material layer 311 and the first separator 313, between the first negative electrode active material layer 312 and the first separator 313, between the second positive electrode active material layer 331 and the second separator 333, and between the second negative electrode active material layer 332 and the second separator 333. The electrolyte section 4 is in contact with a first region 32A1 of the first main surface 32A of the current collector 32 other than the region in contact with the first negative electrode active material layer 312. The electrolyte section 4 is in contact with a second region 32B1 of the second main surface 32B of the current collector 32 other than the region in contact with the second negative electrode active material layer 332.

[0037] The electrolyte portion 4 has fluidity at 25°C. The electrolyte portion is an electrolytic solution that is liquid at 25°C. The electrolyte portion 4 may be gel-like at 25°C. The electrolyte portion 4 contains an electrolyte and a solvent. Examples of the electrolyte include lithium salt, potassium hydroxide, sulfuric acid, and sodium hexafluorophosphate. Examples of the lithium salt include lithium tetrafluoroborate, lithium hexafluorophosphate, and lithium bis(fluorosulfonyl)imide. The solvent dissolves the electrolyte. Examples of the solvent include an organic solvent and water. Examples of the organic solvent include ethylene carbonate, propylene carbonate, γ-butyrolactone, sulfolane, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, dimethyl ether, methyl butyrate, and propyl acetate.

[0038] [Details of the exterior material 2, the current collector 32, the first current collector 34, the first cell 31, the second current collector 35, and the second cell 33, and the first connection terminal portion 5 and the second connection terminal portion 6] <Details of exterior material 2> The outer peripheral portion 21 of the exterior material 2 is disposed at a distance from the first cell 31 and the second cell 33 in a planar direction PD perpendicular to the thickness direction TD. Specifically, the outer peripheral portion 21 is disposed at a distance from each of an end face 341 of the first current collector 34, an end face 3111 of the first positive electrode active material layer 311, an end face of the first negative electrode active material layer 312, an outer peripheral portion 3131 of the first separator 313, an end face 351 of the second current collector 35, an end face 3321 of the second negative electrode active material layer 332, an end face of the second positive electrode active material layer 331, and an outer peripheral portion 3331 of the second separator 333, as viewed in the thickness direction TD.

[0039] <Details of current collector 32> The current collector 32 extends from between the first cell 31 and the second cell 33 to the outer periphery 21 of the exterior packaging material 2. The outer periphery 321 of the current collector 32 is sandwiched between the outer periphery 21. The outer periphery 321 of the current collector 32 is sandwiched between the outer periphery 21. In other words, the outer periphery 321 is sandwiched between the laminated portion 23 of the films 2A and 2B. This fixes the outer periphery 321 of the current collector 32 to the laminated portion 23. The electrolyte portion 4 also crosses the current collector 32. In other words, the current collector 32 divides the electrolyte portion 4 in the thickness direction TD. The electrolyte portion 4 located on the first main surface 32A side of the current collector 32 does not communicate with the electrolyte portion 4 located on the second main surface 32B side.

[0040] <Details of the first cell 31> An end face 341 (excluding an end face corresponding to a protruding end 342 described later) of the first current collector 34 is flush with an end face 3111 of the first positive electrode active material layer 311. That is, the end face 341 is continuous with the end face 3111 in the thickness direction TD. An outer peripheral portion 3131 of the first separator 313 protrudes outward from the first positive electrode active material layer 311 and the first negative electrode active material layer 312 in the planar direction PD. A central portion 3132 of the first separator 313 overlaps both the first positive electrode active material layer 311 and the first negative electrode active material layer 312 when viewed in the thickness direction TD.

[0041] <Details of the second cell 33> An end face 351 of the second current collector 35 (excluding an end face corresponding to a protruding end 352, which will be described later) is flush with an end face 3321 of the second negative electrode active material layer 332. That is, the end face 351 is continuous with the end face 3321. An outer peripheral portion 3331 of the second separator 333 protrudes outward from the second positive electrode active material layer 331 and the second negative electrode active material layer 332 in the planar direction PD. A central portion 3332 of the second separator 333 overlaps both the second positive electrode active material layer 331 and the second negative electrode active material layer 332 in the thickness direction TD.

[0042] <First connection terminal portion 5 and second connection terminal portion 6> The battery 1 further includes a first connection terminal 5 and a second connection terminal 6. The first connection terminal 5 is electrically connected to the first current collector 34. The first connection terminal 5 penetrates the outer periphery 21 of the exterior packaging material 2. The first connection terminal 5 crosses the first side 241 when viewed in the thickness direction. The first connection terminal 5 is made of a conductive material. The first connection terminal 5 has one end 51 and the other end 52. The one end 51 contacts a protruding end 342 of the first current collector 34. The protruding end 342 is a portion of the first current collector 34 adjacent to the first side 241, and protrudes outward from an end face 3111 adjacent to the first side 241. The other end 52 is exposed from the exterior packaging material 2.

[0043] The second connection terminal 6 is electrically connected to the second current collector 35. The second connection terminal 6 penetrates the outer periphery 21 of the exterior packaging material 2. The second connection terminal 6 traverses the first side 241. The second connection terminal 6 is arranged at a distance from the first connection terminal 5 in the direction along the first straight line L1. The second connection terminal 6 is made of a conductive material. The second connection terminal 6 has one end 61 and the other end 62. The one end 61 contacts a protruding end 352 of the second current collector 35. The protruding end 352 is a portion of the second current collector 35 adjacent to the first side 241, and protrudes outward from an end face 3321 adjacent to the first side 241. The other end 62 is exposed from the exterior packaging material 2.

[0044] It should be understood that the embodiments disclosed herein are illustrative in all respects and are not limiting in any respect. The scope of the present disclosure is defined not by the above description but by the claims, and it is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0045] REFERENCE SIGNS LIST 1 battery, 2 exterior material, 2A film, 2B film, 3 battery body, 4 electrolyte portion, 5 first connection terminal portion, 6 second connection terminal portion, 21 outer periphery, 22 central portion, 23 laminated portion, 23A, 23B film, 24 outer edge, 31 first cell, 32 current collector, 32A first main surface, 32A1 first region, 32B second main surface, 32B1 second region, 33 second cell, 34 first current collector, 35 second current collector, 51 one end, 52 other end, 61 one end, 62 other end, 203A, 203B resin layer, 204A, 204B metal foil, 205A, 205B second resin layer, 241 first side, 242 second side, 243, 244 both sides, 311 first positive electrode active material layer, 312 First negative electrode active material layer, 313 first separator, 321 outer periphery, 331 second positive electrode active material layer, 332 second negative electrode active material layer, 333 second separator, 341 end face, 342 protruding end, 351 end face, 352 protruding end, 3111 end face, 3131 outer periphery, 3132 central portion, 3321 end face, 3331 outer periphery, 3332 central portion, L1 first straight line, P plane, PD plane direction, TD thickness direction

Claims

1. Exterior materials and a battery body housed in the exterior packaging; an electrolyte portion accommodated in the exterior material and in contact with the battery body; the battery body includes a first cell, a current collector, and a second cell arranged in that order in a thickness direction; the exterior material has an outer circumferential portion disposed at intervals from the first cell and the second cell in a planar direction perpendicular to the thickness direction, The electrolyte portion has fluidity at 25°C, The current collector extends from between the first cell and the second cell to the outer periphery.

2. the exterior material is a laminated portion of two films, and includes a laminated portion in which the two films are crimped together at the outer periphery, The battery according to claim 1 , wherein the outer periphery of the current collector is sandwiched between the outer periphery.

3. The film comprises a thermoplastic resin, The battery according to claim 2 , wherein the outer periphery is a fused portion of the thermoplastic resin.

4. The battery body is a first current collector located on the opposite side of the current collector as viewed from the first cell; a second current collector located on the opposite side of the current collector as viewed from the second cell, The first cell is a first positive electrode active material layer in contact with the first current collector; a first negative electrode active material layer in contact with the current collector, The second cell is a second positive electrode active material layer in contact with the current collector; a second negative electrode active material layer in contact with the second current collector, the first current collector includes an end surface that is flush with an end surface of the first positive electrode active material layer, The battery according to claim 1 or 2, wherein the second current collector includes an end surface that is flush with an end surface of the second negative electrode active material layer.

5. the first cell further includes a first separator located between the first positive electrode active material layer and the first negative electrode active material layer; the second cell further includes a second separator located between the second positive electrode active material layer and the second negative electrode active material layer, an outer peripheral portion of the first separator protrudes outward from the first positive electrode active material layer or the first negative electrode active material layer in the planar direction; The battery according to claim 4 , wherein an outer peripheral portion of the second separator protrudes outward from the second positive electrode active material layer or the second negative electrode active material layer in the planar direction.

6. a first connection terminal electrically connected to the first current collector, the first connection terminal penetrating an outer periphery of the exterior material; 3. The battery according to claim 1, further comprising: a second connection terminal electrically connected to the second current collector, the second connection terminal penetrating an outer periphery of the exterior material.

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