Battery

Abstract

Provided is a battery in which deterioration of battery performance can be suppressed. The present invention contributes to Sustainable Development Goal 9: "Industry, Innovation, and Infrastructure." This laminate film-type battery comprises: a laminate film that forms a bag shape by sealing edge regions that face each other and overlap each other along an outer peripheral edge; and a power generation element that is externally packaged by the laminate film and to which a positive electrode power supply tab and a negative electrode power supply tab are connected. A sealing portion, which is a portion where the overlapped edge regions are sealed, includes: a metal sealing portion in which metal layers facing each other are welded; and a resin sealing portion in which resin layers facing each other are welded. In the laminate film-type battery, a first power supply tab is led out from the metal sealing portion to the outside, and a second power supply tab is led out from the resin sealing portion to the outside.

Description

Battery

[0001] The present invention relates to a battery, and more particularly to a laminated film type battery.

[0002] Conventionally, lithium ion secondary batteries have been used in portable electronic devices such as mobile phones or notebook personal computers, and electric vehicles. In lithium ion secondary batteries, all-solid-state lithium ion secondary batteries that do not use organic solvents have attracted attention. All-solid-state secondary batteries such as all-solid-state lithium ion secondary batteries use solid electrolytes that do not use organic solvents instead of conventional organic solvent-based electrolytes. All-solid-state secondary batteries have a structure in which a positive electrode layer, a negative electrode layer, and a solid electrolyte layer are laminated. Since the electrodes of all-solid-state secondary batteries using sulfide-based solid electrolytes generate hydrogen sulfide gas due to moisture and the electrical characteristics deteriorate, all-solid-state secondary batteries require a sealed structure that blocks moisture. In addition, since reactions with moisture are also a problem with hydride-based solid electrolytes, etc., a sealed structure that can block the intrusion of moisture is required.

[0003] There is a laminated film type battery in which a laminated film is applied to the exterior material of an all-solid-state secondary battery. The laminated film used for the battery has a laminated structure in which a base layer, a sand layer, and a sealant layer are laminated. A typical laminated film uses an insulating resin for the base layer, a metal foil for the sand layer, and a heat-sealable resin for the sealant layer. When using a laminated film as the exterior material of a battery, one sheet of the three-layer laminated film is folded in two or two sheets of the same shape are overlapped to form a bag shape. When forming a bag shape, when folding in two, the three sides where the heat-sealable resins of the laminated film are in surface contact are heat-sealed. When two sheets of the same shape are overlapped, the four sides where the heat-sealable resins of the laminated film are in surface contact are heat-sealed. The battery element is enclosed inside the bag-shaped laminated film. Two power supply tabs (positive electrode tab, negative electrode tab) are led out from the battery element inside the laminated film through between the opposing heat-sealable resins to the outside (see, for example, Patent Document 1).

[0004] Japanese Patent Application Laid-Open No. 2008-84666

[0005] In a laminated film type battery, since the sealant layer of the laminated film (outer packaging material) is composed of a heat-sealing resin, moisture permeates into the interior from the sealed resin portion of the bag-shaped laminated film. Therefore, there has been a problem in that the amount of moisture permeating into the bag-shaped laminated film increases in proportion to the area of the heat-sealing resin in contact with the outside air at the sealed portion, resulting in deterioration of battery performance.

[0006] The present invention has been made to solve the above problems. That is, one of the objects of the present invention is to provide a battery capable of suppressing deterioration of battery performance by reducing the area of the heat-sealing resin portion in contact with the outside air at the sealed portion of the outer packaging material.

[0007] To solve the above problems, a battery according to the present invention includes an outer packaging material having a multilayer laminated structure including metal and resin, and is packaged by the outer packaging material in which edge regions facing each other and overlapping along the outer peripheral edge are sealed to form a bag shape. A power generation element to which a first power supply tab, which is one of a positive electrode power supply tab and a negative electrode power supply tab, and a second power supply tab, which is the other of the positive electrode power supply tab and the negative electrode power supply tab, are connected. The sealed portion, which is a portion where the overlapping edge regions are sealed, includes a metal sealed portion where metals facing each other are welded and a resin sealed portion where resins facing each other are heat-sealed. The first power supply tab is led out to the outside from the metal sealed portion, and the second power supply tab is led out to the outside from the metal sealed portion or the resin sealed portion in a state insulated from the first power supply tab.

[0008] According to the present invention, deterioration of battery performance can be suppressed. The effects described here are not necessarily limited, and any effect described in the present disclosure may be applicable.

[0009] Figure 1 is a perspective view showing an example of the configuration of a battery according to the first embodiment. Figure 2 is an exploded perspective view illustrating the components of the battery according to the first embodiment. Figure 3 is a cross-sectional view showing an example of the configuration of an electrode body. Figure 4 is a diagram showing an example of the configuration of the outer casing material (before processing) before use in the battery. Figure 5 is a cross-sectional view along line IVa-IVa in Figure 4. Figure 6 is a cross-sectional view along line IVb-IVb in Figure 4. Figure 7 is a cross-sectional view along line IVc-IVc in Figure 4. Figure 8 is a plan view showing an example of the configuration of a battery according to the first embodiment. Figure 9 is a cross-sectional view along line VIIIa-VIIIa in Figure 8. Figure 10 is a cross-sectional view along line VIIIb-VIIIb in Figure 8. Figure 11 is a cross-sectional view along line VIIIc-VIIIc in Figure 8. Figure 12 is a cross-sectional view along line VIIId-VIIId in Figure 8. Figure 13 is a diagram showing an example of the configuration of the outer casing material before use in the battery according to the second embodiment. Figure 14 is a cross-sectional view along line XIII-XIII in Figure 13. Figure 15 is a plan view showing an example of the configuration of a battery according to the second embodiment. Figure 16 is a cross-sectional view along line XVa-XVa in Figure 15. Figure 17 is a cross-sectional view along line XVb-XVb in Figure 15. Figure 18 is a cross-sectional view along line XVc-XVc in Figure 15. Figure 19 is a cross-sectional view along line XVd-XVd in Figure 15. Figure 20 is a diagram showing an example of the configuration of the exterior material (before processing) before use in the battery according to the third embodiment. Figure 21 is a perspective view of the battery element. Figure 22 is a cross-sectional view for explaining the structure of the resin sealing part. Figure 23 is a cross-sectional view for explaining the structure of the resin sealing part. Figure 24 is a diagram showing an example of the configuration of the exterior material 200 before use in the battery according to the fourth embodiment. Figure 25 is a cross-sectional view along line XXIV-XXIV in Figure 24. Figure 26 is a plan view showing an example of the configuration of the battery according to the fourth embodiment. Figure 27 is a cross-sectional view along line XXVI-XXVI in Figure 26.

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings of the embodiments, the same or corresponding parts may be denoted by the same reference numerals.

[0011] <<First Embodiment>> A battery according to the first embodiment of the present invention will now be described. In the following description of the embodiments, the term "battery" is used, but it may be replaced with terms such as all-solid-state battery or laminate film battery. The battery may be a primary battery or a secondary battery.

[0012] Figure 1 is a perspective view showing an example of the configuration of a battery according to the first embodiment. Figure 2 is an exploded perspective view illustrating the components of the battery according to the first embodiment. As shown in Figures 1 and 2, the battery includes a battery element 100 and an outer casing material 200. The battery element 100 is sometimes referred to as a "power generation element".

[0013] As shown in Figure 2, the battery element 100 includes an electrode body 110, a positive electrode tab 120 attached to the positive electrode side of the electrode body 110, and a negative electrode tab 130 attached to the negative electrode side of the electrode body 110.

[0014] Figure 3 is a cross-sectional view showing an example of the configuration of the electrode body 110. The electrode body 110 is composed of a battery molded body. As shown in Figure 3, the battery molded body includes a positive electrode side layer 113, a negative electrode side layer 114, and a solid electrolyte layer 115 interposed between the positive electrode side layer 113 and the negative electrode side layer 114. The battery molded body has a laminated structure in which the solid electrolyte layer 115 is laminated so as to be interposed between the positive electrode side layer 113 and the negative electrode side layer 114.

[0015] (Positive electrode side layer) The positive electrode side layer 113 includes a positive electrode layer 116 and a positive electrode current collector layer 117. The positive electrode side layer 113 may consist only of the positive electrode layer 116, or it may include the positive electrode layer 116, the positive electrode current collector layer 117, and other layers having other functions besides these layers. The positive electrode side layer 113 may include the positive electrode layer 116 and other layers.

[0016] The positive electrode layer 116 is composed of a molded body of a positive electrode mixture containing, for example, a positive electrode active material, a conductive additive, and a solid electrolyte. The positive electrode active material is not particularly limited as long as it is a positive electrode active material that has been used in conventional lithium-ion secondary batteries, that is, an active material that can intercept and release Li ions. A specific example of the positive electrode active material is LiM ｘ Mn ２－ｘ O ４(However, M is at least one element selected from the group consisting of Li, B, Mg, Ca, Sr, Ba, Ti, V, Cr, Fe, Co, Ni, Cu, Al, Sn, Sb, In, Nb, Mo, W, Y, Ru, and Rh, and 0.01 ≦ x ≦ 0.5) The spinel-type lithium manganese composite oxide represented by, Li ｘ Mn （１－ｙ－ｘ） Ni ｙ M ｚ O （２－ｋ） Fl (However, M is at least one element selected from the group consisting of Co, Mg, Al, B, Ti, V, Cr, Fe, Cu, Zn, Zr, Mo, Sn, Ca, Sr, and W, and 0.8 ≦ x ≦ 1.2, 0 < y < 0.5, 0 ≦ z ≦ 0.5, k + l < 1, -0.1 ≦ k ≦ 0.2, 0 ≦ l ≦ 0.1) The layered compound represented by, LiCo １－ｘ M ｘ O ２ (However, M is at least one element selected from the group consisting of Al, Mg, Ti, Zr, Fe, Ni, Cu, Zn, Ga, Ge, Nb, Mo, Sn, Sb, and Ba, and 0 ≦ x ≦ 0.5) The lithium cobalt composite oxide represented by, LiNi １－ｘ M ｘ O ２ (However, M is at least one element selected from the group consisting of Al, Mg, Ti, Zr, Fe, Co, Cu, Zn, Ga, Ge, Nb, Mo, Sn, Sb, and Ba, and 0 ≦ x ≦ 0.5) The lithium nickel composite oxide represented by, LiM １－ｘ [[ID=第24]]Q ｘ PO ４ (However, M is at least one element selected from the group consisting of Fe, Mn, and Co, and Q is at least one element selected from the group consisting of Al, Mg, Ti, Zr, Ni, Cu, Zn, Ga, Ge, Nb, Mo, Sn, Sb, and Ba, and 0 ≦ x ≦ 0.5) The olivine-type composite oxide represented by, Li ４ Ti ５ O １２ Examples include lithium titanium composite oxides represented by, and only one of these may be used, or two or more thereof may be used in combination.

[0017] The average particle size of the positive electrode active material is preferably 1 μm or more, more preferably 2 μm or more, preferably 10 μm or less, and more preferably 8 μm or less. The positive electrode active material may be primary particles or secondary particles formed by aggregation of primary particles. Using a positive electrode active material with an average particle size within the above range allows for a larger interface with the solid electrolyte, thereby improving the load characteristics of the battery.

[0018] The positive electrode active material preferably has a reaction-inhibiting layer on its surface to suppress its reaction with the solid electrolyte.

[0019] In a molded positive electrode mixture, direct contact between the positive electrode active material and the solid electrolyte can cause the solid electrolyte to oxidize, forming a resistance layer and potentially reducing the ionic conductivity within the molded body. By providing a reaction-inhibiting layer on the surface of the positive electrode active material to suppress its reaction with the solid electrolyte, direct contact between the positive electrode active material and the solid electrolyte can be prevented, thereby suppressing the reduction in ionic conductivity within the molded body due to oxidation of the solid electrolyte.

[0020] The reaction suppression layer should be composed of a material that has ionic conductivity and can suppress the reaction between the positive electrode active material and the solid electrolyte. Examples of materials that can constitute the reaction suppression layer include oxides containing Li and at least one element selected from the group consisting of Nb, P, B, Si, Ge, Ti, and Zr, more specifically, LiNbO ３ Nb-containing oxides such as Li ３ PO ４ Li ３ BO ３ Li ４ SiO ４ Li ４ GeO ４ LiTio ３ LiZrO ３ These are some examples. The reaction suppression layer may contain only one of these oxides, or it may contain two or more, and furthermore, multiple of these oxides may form a composite compound. Among these oxides, it is preferable to use an Nb-containing oxide, such as LiNbO ３ It is more preferable to use [this].

[0021] The reaction-inhibiting layer is preferably present on the surface in an amount of 0.1 to 1.0 part by mass per 100 parts by mass of the positive electrode active material. Within this range, the reaction between the positive electrode active material and the solid electrolyte can be effectively suppressed. Methods for forming the reaction-inhibiting layer on the surface of the positive electrode active material include the sol-gel method, mechanofusion method, CVD method, and PVD method.

[0022] The content of the positive electrode active material in the positive electrode mixture is preferably 60 to 95% by mass.

[0023] Examples of conductive additives for the positive electrode include graphite (natural graphite, artificial graphite), graphene, carbon black, carbon nanofibers, carbon nanotubes, and other carbon materials. The content of the conductive additive in the positive electrode mixture is preferably 1 to 10% by mass.

[0024] The solid electrolyte to be included in the positive electrode mixture is not particularly limited as long as it has lithium ion conductivity, and for example, sulfide-based solid electrolytes, hydride-based solid electrolytes, halide-based solid electrolytes, oxide-based solid electrolytes, etc., can be used.

[0025] Examples of sulfide-based solid electrolytes include Li ２ S-P ２ S ５ Li ２ S-SiS ２ Li ２ S-P ２ S ５ -GeS ２ Li ２ S-B ２ S ３ Examples include glass alloys, and in recent years, Li has attracted attention as a material with high lithium-ion conductivity. １０ GeP ２ S １２ (LGPS system) and Li ６ PS ５ Cl (argyrodite type) can also be used. Among these, argyrodite type materials with particularly high lithium ion conductivity and high chemical stability are preferred.

[0026] Examples of hydride-based solid electrolytes include LiBH ４ LiBH４ Solid solutions of the following alkali metal compounds (e.g., LiBH) ４ Examples include those with a molar ratio of 1:1 to 20:1 between the solid solution and the alkali metal compound. Examples of alkali metal compounds in the solid solution include at least one selected from the group consisting of lithium halides (LiI, LiBr, LiF, LiCl, etc.), rubidium halides (RbI, RbBr, RbF, RbCl, etc.), cesium halides (CsI, CsBr, CsF, CsCl, etc.), lithium amide, rubidium amide, and cesium amide.

[0027] Examples of halide-based solid electrolytes include monoclinic LiAlCl ４ , defective spinel type or layered structure LiInBr ４ Monoclinic Li ６－３ｍ Y ｍ X ６ (However, this includes cases where 0 < m < 2 and X = Cl or Br), and other publicly known examples can also be used, such as those described in International Publication No. 2020 / 070958 and International Publication No. 2020 / 070955.

[0028] Examples of oxide-based solid electrolytes include garnet-type Li ７ La ３ Zr ２ O １２ , NASICON type Li １＋Ｏ Al １＋Ｏ Ti ２－Ｏ (PO ４ ) ３ Li １＋ｐ Al １＋ｐ Ge ２－ｐ (PO ４ ) ３ Perovskite-type Li ３ｑ La ２／３－ｑ TiO ３ These are some examples.

[0029] Among these solid electrolytes, sulfide-based solid electrolytes are preferred due to their high lithium ion conductivity, sulfide-based solid electrolytes containing Li and P are more preferred, and argyrodite-type sulfide-based solid electrolytes, which have high lithium ion conductivity and high chemical stability, are even more preferred.

[0030] Furthermore, the average particle size of the solid electrolyte is preferably 0.1 μm or larger, and more preferably 0.2 μm or larger, from the viewpoint of reducing grain boundary resistance. On the other hand, from the viewpoint of forming a sufficient contact interface between the active material and the solid electrolyte, it is preferably 10 μm or smaller, and more preferably 5 μm or smaller.

[0031] From the viewpoint of further enhancing ionic conductivity within the positive electrode and improving the output characteristics of the battery, the solid electrolyte content in the positive electrode mixture is preferably 10 parts by mass or more, and more preferably 30 parts by mass or more, when the positive electrode active material content is 100 parts by mass. However, if the amount of solid electrolyte in the positive electrode mixture is too high, the amount of other components will decrease, and the effects of those components may be reduced. Therefore, the solid electrolyte content in the positive electrode mixture is preferably 65 parts by mass or less, and more preferably 60 parts by mass or less, when the positive electrode active material content is 100 parts by mass.

[0032] The positive electrode current collector layer 117 can be made of metal foil such as aluminum or stainless steel, perforated metal, mesh, expanded metal, foamed metal, carbon sheet, etc.

[0033] A molded positive electrode mixture can be formed, for example, by compressing a positive electrode mixture prepared by mixing a positive electrode active material, a conductive additive, a solid electrolyte, and a binder added as needed, using pressure molding. In the case of a positive electrode having a current collector (i.e., a positive electrode layer and a positive electrode current collector layer), the molded positive electrode mixture formed by the above method can be bonded to the current collector by pressure, or the current collector can be pressure-molded together with the positive electrode mixture to form an integrated molded body. The thickness of the molded positive electrode mixture (in the case of a positive electrode having a current collector, the thickness of the molded positive electrode mixture per side of the current collector; the same applies hereinafter) is preferably 200 μm or more from the viewpoint of increasing the battery capacity. Furthermore, the thickness of the molded positive electrode mixture is preferably 2000 μm or less from the viewpoint of improving load characteristics.

[0034] (Negative electrode side layer) The negative electrode side layer 114 includes a negative electrode layer 118 and a negative electrode current collector layer 119. The negative electrode side layer 114 may consist only of the negative electrode layer 118, or it may include the negative electrode layer 118, the negative electrode current collector layer 119, and other layers having other functions besides these layers. The negative electrode side layer 114 may include the negative electrode layer 118 and other layers.

[0035] The negative electrode layer 118 is composed of a molded body of a negative electrode mixture containing, for example, a negative electrode active material, a conductive additive, and a solid electrolyte.

[0036] As the negative electrode active material, one or more carbon-based materials capable of intercalating and releasing lithium, such as graphite, pyrolytic carbons, cokes, glassy carbons, calcined organic polymer compounds, mesocarbon microbeads (MCMBs), and carbon fibers, can be used. In addition, elements such as Si, Sn, Ge, Bi, Sb, and In, compounds and alloys thereof, lithium-containing nitrides or lithium-containing oxides that can be charged and discharged at low voltages close to lithium metal, lithium metal, and lithium / aluminum alloys can also be used as negative electrode active materials. For example, Li ４ Ti ５ O １２ YaTiO ２ NbO ２．５－δ (0≦δ≦0.5), MoO ３－δ (0 ≤ δ ≤ 1), WO ３－δ (0≦δ≦1), TiNb ２ O ７ Metal oxides such as WS ２ MoS ２ The solid electrolyte, which can also be used as a negative electrode active material, is not particularly limited as long as it has lithium ion conductivity. For example, like the positive electrode layer 116, sulfide-based solid electrolytes, hydride-based solid electrolytes, halide-based solid electrolytes, oxide-based solid electrolytes, etc., can be used.

[0037] The negative electrode current collector layer 119 can be made of metal foil such as aluminum or stainless steel, perforated metal, mesh, expanded metal, foamed metal, carbon sheet, etc.

[0038] A molded negative electrode mixture can be formed, for example, by compressing a negative electrode mixture prepared by mixing a negative electrode active material, a conductive additive, a solid electrolyte, and a binder added as needed, using pressure molding. In the case of a negative electrode having a current collector (i.e., a negative electrode layer and a negative electrode current collector layer), the molded negative electrode mixture formed by the above method can be bonded to the current collector by pressure, or the current collector can be pressure-molded together with the negative electrode mixture to form an integrated molded body. The thickness of the molded negative electrode mixture (in the case of a negative electrode having a current collector, the thickness of the molded negative electrode mixture per side of the current collector; the same applies hereinafter) is preferably 200 μm or more from the viewpoint of increasing the battery capacity. Furthermore, the thickness of the molded negative electrode mixture is preferably 2000 μm or less from the viewpoint of improving load characteristics.

[0039] (Solid Electrolyte Layer) The solid electrolyte layer 115 contains a solid electrolyte. One or more of the various sulfide-based solid electrolytes, hydride-based solid electrolytes, and oxide-based solid electrolytes exemplified above as usable in the positive electrode layer 116 can be used as the solid electrolyte. However, in order to improve battery characteristics, it is desirable to include a sulfide-based solid electrolyte, and it is even more desirable to include a sulfide-based solid electrolyte in the positive electrode, negative electrode, and solid electrolyte layer 115. The solid electrolyte layer 115 may have a porous material such as a resin nonwoven fabric as a support. The solid electrolyte layer 115 can be formed by compressing the solid electrolyte by pressure molding, or by applying a solid electrolyte layer forming composition prepared by dispersing the solid electrolyte in a solvent onto a substrate, positive electrode, or negative electrode, drying it, and performing pressure molding such as a press treatment as necessary.

[0040] When selecting a solvent for the composition for forming the solid electrolyte layer, it is preferable to choose one that does not easily degrade the solid electrolyte. In particular, since sulfide-based solid electrolytes and hydride-based solid electrolytes undergo chemical reactions with even trace amounts of water, it is preferable to use a nonpolar aprotic solvent, such as hydrocarbon solvents like hexane, heptane, octane, nonane, decane, decalin, toluene, and xylene. It is especially preferable to use an ultra-dehydrated solvent with a water content of 0.001% by mass (10 ppm) or less. In addition, fluorine-based solvents such as "Bartrell®" from Mitsui DuPont Fluorochemicals, "Zeolora®" from Nippon Zeon Corporation, and "Novec®" from Sumitomo 3M Corporation, as well as non-aqueous organic solvents such as dichloromethane and diethyl ether, can also be used. The thickness of the solid electrolyte layer 115 is preferably 10 to 300 μm.

[0041] The positive electrode tab 120 is made of a conductive material. The positive electrode tab 120 is a plate-shaped body made of a conductive material such as metal. The negative electrode tab 130 is made of a conductive material. The negative electrode tab 130 is a plate-shaped body made of a conductive material such as metal. Note that the shape of the positive electrode tab 120 and the negative electrode tab 130 is not limited to a plate shape, and may be various other shapes besides plates.

[0042] The positive electrode tab 120 attached to the positive electrode side of the electrode body 110 functions as the positive electrode terminal of the battery. The negative electrode tab 130 attached to the negative electrode side of the electrode body 110 functions as the negative electrode terminal of the battery. The material of the tabs is not particularly limited, but when a sulfide-based solid electrolyte is used, it is desirable to use a metal that is resistant to sulfidation, resistant to each electrode potential, and weldable to the sand layer 200b of the outer casing material 200.

[0043] (Exterior Material) The exterior material 200 is a film-like or sheet-like exterior component that covers the battery element 100. The exterior material 200 is sometimes referred to as "laminate film". Figure 4 is a diagram showing an example of the structure of the exterior material 200 (before processing) before use in the battery. Figure 5 is a cross-sectional view along the line IVa-IVa in Figure 4. Figure 6 is a cross-sectional view along the line IVb-IVb in Figure 4. Figure 7 is a cross-sectional view along the line IVc-IVc in Figure 4.

[0044] The exterior material 200 has a rectangular planar shape. The exterior material 200 includes a main structural part 201 and a metal exposed part 202.

[0045] In the exterior material 200, the main structural portion 211 is formed in all areas except for a rectangular area with a predetermined width on the inside along a portion of the first side L1, when viewed from the direction normal to the exterior material 200.

[0046] As shown in Figure 5, the main structural part 201 of the exterior material 200 has a structure in which a base layer 200a, a sand layer 200b, and a sealant layer 200c are laminated. In the main structural part 201, the base layer 200a is formed on the surface of the sand layer 200b that faces the outside of the battery, and the sealant layer 200c is formed on the surface of the sand layer 200b that faces the inside of the battery.

[0047] The base layer 200a is the outermost layer when the battery element 100 is enclosed. The base layer 200a is water-resistant, heat-resistant, impact-resistant, and has moisture-proof and gas-blocking properties. The base layer 200a is made of a resin material such as PET (polyethylene terephthalate), PA (polyamide), or PP (polypropylene). However, the resin material is not limited to these examples. The base layer 200a may be made of one or more types of resin materials.

[0048] The sand layer 200b is a layer located between the base layer 200a and the sealant layer 200c. The sand layer 200b is a layer composed of metals such as Al, SUS, Ni, Cu, and Fe. However, the metals are not limited to these exemplified materials. The sand layer 200b may be composed of one or more types of metals.

[0049] The sealant layer 200c is a layer having adhesive properties. The sealant layer 200c is composed of a heat-weldable resin with a relatively low melting point. The heat-weldable resin is composed of heat-weldable resin materials such as PE (polyethylene) and PP (polypropylene). However, the resin material is not limited to these exemplified materials.

[0050] In the outer packaging material 200, the exposed metal portion 202 is formed along a portion of the first side L1 of the outer packaging material 200, with a predetermined width, when viewed from the normal direction of the outer packaging material 200. The exposed metal portion 202 is formed to be symmetric with respect to the center line C1 passing through the center of the first side L1. As a result, when the outer packaging material 200 forms a bag shape, the sand layer 200b (metal layer) of the exposed metal portion 202 overlaps perfectly, allowing for efficient formation of the metal sealing portion R2. Furthermore, the distance from the center line C1 along the outer edge of the exposed metal portion 202 is formed to be greater than the width of the positive electrode tab 120. Note that the exposed metal portion 202 is formed straddling the center line C1, and it is sufficient that the width along the outer edge of the portion where the sand layer 200b (metal) of each exposed metal portion 202 overlaps when the outer packaging material 200 forms a bag shape is greater than the width of the positive electrode tab 120. The exposed metal portion 202 does not necessarily need to be formed to be symmetrical with respect to the center line C1 as the axis of symmetry.

[0051] As shown in Figures 6 and 7, the exposed metal portion 202 has a single-layer structure consisting only of the sand layer 200b. (That is, the base layer 200a and sealant layer 200c are not formed on both sides of the sand layer 200b.)

[0052] The outer casing material 200 is used by processing each predetermined region of two areas (hereinafter sometimes referred to as "the first part (the upper half of the outer casing material 200 in Figure 4)" and "the second part (the lower half of the outer casing material 200 in Figure 4)") which are symmetrical with respect to the center line C1 passing through the center of the first side L1, into a shape (for example, a concave shape) that forms a housing space for housing the electrode body 110. Furthermore, the outer casing material 200 is folded back with the center line C1 as the folded portion, and edge regions having a predetermined width along the outer edges facing each other in the folded state are overlapped, the overlapped edge regions are sealed, and the bag-shaped (bag form) is used in the battery.

[0053] <Structure> The structural features of the battery according to the first embodiment will be explained using Figure 8. Figure 8 is a plan view showing an example of the configuration of the battery according to the first embodiment. In the battery of Figure 8, the left side of the two opposing sides in the lateral direction of the battery is referred to as the first side L11, and the side opposite the first side L11 is referred to as the second side L12. In the vertical direction, the upper side of the two opposing sides is referred to as the third side L13, and the side opposite the third side L13 is referred to as the fourth side L14.

[0054] As previously described, the outer casing material 200 is processed so that predetermined regions contained in the first and second parts, which face each other on either side of the electrode body 110, are concave. The outer casing material 200 has an overlapping edge region around the concave part of the first part and an overlapping edge region around the concave part of the second part. The outer casing material 200 has its overlapping edge regions along three sides of the battery (first side L11 to third side L13) sealed, forming a bag shape.

[0055] The portion where the overlapping edge regions along the three sides (first side L11 to third side L13) are sealed is referred to as the "sealed portion R1". The sealed portion R1 includes a metal sealed portion R2 and a resin sealed portion R3. The metal sealed portion R2 is formed along the portion of the first side L11 between a first position P1 and a second position P2, with a predetermined width on its inside. The first position P1 is at one end of the first side L11, and the second position P2 is between the upper end of the positive electrode tab 120 in the width direction and the other end of the first side L11. For example, the second position P2 is located at a predetermined distance from the other end of the positive electrode tab 120 in the width direction.

[0056] The resin sealing portion R3 is formed along the portion between the second position P2 of the first side L11 and the other end of the first side L11, the third side L13, and the second side L12, with a predetermined width on the inside of these.

[0057] Figure 9 is a cross-sectional view along line VIIIa-VIIIa in Figure 8. Figure 10 is a cross-sectional view along line VIIIb-VIIIb in Figure 8. In the metal sealing portion R2, as shown in Figure 9, the sand layer 200b (metal layer) made of metal of the metal exposed portion 202 of the first part of the exterior material 200 and the sand layer 200b (metal layer) of the metal exposed portion 202 of the second part of the exterior material 200 are directly stacked on top of each other, or, as shown in Figure 10, the sand layer 200b (metal layer) of the metal exposed portion 202 of the first part and the sand layer 200b (metal layer) of the metal exposed portion 202 of the second part are stacked on top of each other via the positive electrode tab 120.

[0058] In the metal sealing portion R2, the first and second sand layers 200b (metal layers) are directly facing each other or overlapping via the positive electrode tab 120. In a linear portion of the overlapping area (shown by the dotted line a in Figure 8), the sand layers 200b (metal layers) are welded together, or the sand layers 200b (metal layers) are welded together with a portion of the positive electrode tab 120, thereby joining the metals and sealing the portion. There are no resin portions in the metal sealing portion R2 that come into contact with the outside air.

[0059] Figure 11 is a cross-sectional view along line VIIIc-VIIIc in Figure 8. Figure 12 is a cross-sectional view along line VIIId-VIIId in Figure 8. In the resin sealing portion R3, as shown in Figure 11, the sealant layer 200c of the main structural portion 201 of the first part of the exterior material 200 and the sealant layer 200c of the main structural portion 201 of the second part of the exterior material 200 are directly overlapped, or, as shown in Figure 12, the sealant layer 200c of the main structural portion 201 of the first part of the exterior material 200 and the sealant layer 200c of the main structural portion 201 of the second part are overlapped via the negative electrode tab 130. Furthermore, the sealant layer 200c insulates the negative electrode tab 130 from the sand layer 200b (metal layer), preventing a short circuit and loss of battery function due to the negative electrode tab 130 being electrically connected to the positive electrode tab 120 (see Figure 10), which is in contact with the sand layer 200b (metal layer), via the sand layer 200b (metal layer).

[0060] The resin-sealed portion R3 is sealed by the first portion and the second portion having their respective sealant layers 200c facing each other and overlapping, either directly or via the negative electrode tab 130, and either welding (heat-sealing) the sealant layers 200c to each other in the overlapped portion, or by welding (heat-sealing) the sealant layers 200c to each of the negative electrode tabs 130.

[0061] The bag-shaped outer packaging material 200 has a storage space formed by two opposing recesses. The electrode body 110, to which the positive electrode tab 120 and the negative electrode tab 130 are attached, is housed in the storage space.

[0062] The positive electrode tab 120 attached to the electrode body 110 is led out of the battery through the gap between the opposing sand layers 200b (metal layers) (see Figure 10). The positive electrode tab 120 is led out from the first side L11 of the battery.

[0063] The negative electrode tab 130, attached to the electrode body 110, is led out of the battery from the electrode body 110 inside the battery, through the gap between the opposing sealant layers 200c (see Figure 12). The negative electrode tab 130 is led out from the second side L12 opposite the first side L11 of the battery.

[0064] The battery according to the first embodiment has a metal sealing portion R2 in which a part of the sealing portion R1 of the outer casing material 200 is sealed by directly overlapping and partially welding opposing sand layers 200b (metal layers) (see Figure 11), and a part of the sealing portion R1 of the outer casing material 200 is sealed by overlapping and partially welding opposing sand layers 200b (metal layers) facing each other via a positive electrode tab 120 (see Figure 12). As a result, the battery according to the first embodiment can reduce the area of ​​heat-weldable resin in contact with the outside air compared to the conventional method in which the entire overlapping edge region is sealed by welding of heat-weldable resin. Therefore, the battery according to the first embodiment can reduce the amount of moisture permeation and suppress the deterioration of battery performance.

[0065] <Manufacturing Method> The manufacturing method of the battery according to the first embodiment will be described. An electrode body 110 is fabricated, and a positive electrode tab 120 and a negative electrode tab 130 are attached to fabricate a battery element 100. An outer casing material 200 as shown in Figure 4 is prepared, and two predetermined regions at positions that are symmetrical with respect to the center line C1 passing through the center of the first side L1 are processed so that they form a concave shape. In this way, two concave parts are formed in the outer casing material 200.

[0066] The outer material 200 is folded back along the center line C1, and the electrode body 110, to which the positive electrode tab 120 and negative electrode tab 130 are attached, is placed into the housing space formed by two opposing recesses. Then, the edge region around the recess of one of the folded first parts and the edge region around the recess of the other second part are overlapped.

[0067] Subsequently, a portion of the overlapping edge region along the first side L11 of the battery is heat-fused, and the straight portion of the remaining overlapping edge region along the first side L11 (dotted line a in Figure 8) is laser-welded. Alternatively, resistance welding or ultrasonic welding may be used instead of laser welding. Then, the overlapping edge regions along the second side L12 and the third side L13 of the battery are heat-fused, respectively. This seals the three overlapping edges, completing the battery.

[0068] <Effects> As described above, the battery according to the first embodiment of the present invention can reduce the amount of moisture permeation and suppress the deterioration of battery performance.

[0069] <<First Modification>> In the first embodiment described above, a first exterior material corresponding to the first portion above the center line C1 of the exterior material 200 in Figure 4 and a second exterior material corresponding to the second portion below the center line C1 in Figure 4 may be prepared, and recesses may be formed in each, and a bag shape (bag form) may be formed by overlapping and sealing the edge regions around the recesses along the four sides of the first exterior material and the edge regions around the recesses along the four sides of the second exterior material. In this case, the exterior material 200 has its overlapping edge regions along its four sides (first side L11 to fourth side L14) sealed, forming a bag shape (bag form). In this case, the sealed portion R1 in which the overlapping edge regions along the four sides are sealed includes a metal sealed portion R2 and a resin sealed portion R3. The metal sealed portion R2 is formed along the portion between the first position P1 and the second position P2 of the first side L11, with a predetermined width on its inside. The resin sealing portion R3 is formed with a predetermined width inside the portion between the second position P2 of the first side L11 and the other end of the first side L11, the third side L13, the second side L12, and the fourth side L14, along one end and position P1a (see Figure 8). This first modification provides the same effects as the battery according to the first embodiment.

[0070] <<Second Embodiment>> A battery according to the second embodiment of the present invention will be described below. In the following description, the differences from the first embodiment will be the focus, and points that overlap with the first embodiment will not be explained.

[0071] Figure 13 shows an example of the configuration of the exterior material 200 before use in the battery according to the second embodiment. Figure 14 is a cross-sectional view taken along line XIII-XIII in Figure 13.

[0072] As shown in Figure 13, the exterior material 200 has a rectangular planar shape. The exterior material 200 includes a main structural part 211, a metal exposed part 202, and a heat-sealed layer laminated part 203.

[0073] In the exterior material 200, the main structural part 211 is formed in a rectangular shape in the center when viewed from the direction normal to the exterior material 200. The rectangular main structural part 211 is formed so that there is a gap between its outer edge and the outer edge of the exterior material 200.

[0074] In the exterior material 200, the exposed metal portion 202 is formed in all areas except for a part of the region between the outer peripheral end of the main structural portion 211 and the outer peripheral end of the exterior material 200 (the rectangular region in which the heat-sealed layer laminate portion 203 is formed), when viewed from the direction normal to the exterior material 200.

[0075] In the outer packaging material 200, the heat-sealed layer laminated portion 203 is formed along a portion of the second side L2 of the outer packaging material 200, with a predetermined width, when viewed from the normal direction of the outer packaging material 200. The heat-sealed layer laminated portion 203 is formed to be symmetrical with respect to the center line C1 passing through the center of the first side L1. As a result, when the outer packaging material 200 forms a bag shape, the heat-sealed layers 200c2 of the heat-sealed layer laminated portion 203 overlap perfectly, allowing for efficient formation of the resin sealing portion R3. Furthermore, the distance from the center line C1 along the outer edge of the heat-sealed layer laminated portion 203 is formed to be greater than the width of the negative electrode tab 130. Furthermore, the heat-sealed layer laminated portion 203 is formed straddling the center line C1, and it is sufficient that the width along the outer edge of the portion where the heat-sealed layers 200c2 of the heat-sealed layer laminated portions 203 overlap when the outer packaging material 200 forms a bag shape is greater than the width of the negative electrode tab 130. The heat-sealed layer laminated portion 203 does not necessarily need to be formed symmetrically with respect to the center line C1 as the axis of symmetry.

[0076] As shown in Figure 14, the main structural part 211 of the exterior material 200 has a structure in which a base layer 200a, a sand layer 200b, and an insulating layer 200c1 which constitutes part of the sealant layer 200c are laminated. In the main structural part 201, the base layer 200a is formed on the surface of the sand layer 200b that is located on the outside of the battery, and the insulating layer 200c1 is formed on the surface of the sand layer 200b that is located on the inside of the battery. The insulating layer 200c1 is made of an insulating material (for example, 10 １３ Any material having an insulation resistance of Ω·cm or more is acceptable, and it may also be insulating and heat-sealable. The material constituting the insulating layer 200c1 may be a heat-sealable resin, a sheet-like insulating material, or a coated insulating material (coated insulating film), and the material and insulating processing method are not limited. Furthermore, an inorganic insulating material (filler) may be appropriately added to the heat-sealable layer laminate 203 to improve its mechanical and thermal properties.

[0077] The exposed metal portion 202 has a single-layer structure consisting only of the sand layer 200b.

[0078] The heat-sealable layer laminate 203 has a structure in which the sand layer 200b and the heat-sealable layer 200c2, which constitutes the other part of the sealant layer 200c, are laminated together. The heat-sealable layer 200c2 is formed on the surface of the sand layer 200b that is located on the inside of the battery. The heat-sealable layer 200c2 is made of a heat-sealable resin.

[0079] Furthermore, if the insulating layer 200c1 of the main structural part 211 is made of a heat-weldable resin, the insulating layer 200c1 and the heat-weldable layer 200c2 of the main structural part 211 may be made separately or as a single unit.

[0080] Figure 15 is a plan view showing an example of the battery configuration according to the second embodiment. The outer casing material 200 is processed so that predetermined areas contained in the first and second parts, which face each other on either side of the electrode body 110, are concave. The outer casing material 200 has an overlapping edge region around the concave part of the first part and an overlapping edge region around the concave part of the other second part. The outer casing material 200 has its overlapping edge regions along three sides of the battery (first side L11 to third side L13) sealed, forming a bag shape.

[0081] The sealing portion R1 includes a metal sealing portion R2 and a resin sealing portion R3.

[0082] The metal sealing portion R2 is formed along the first side L11, the third side L13, and the portion between the third position P3 and the fourth position P4 of the second side L12, with a predetermined width on the inside of these. The third position P3 is at one end of the second side L12, and the fourth position P4 is at a predetermined distance from one end in the width direction of the negative electrode tab 130 and the upper end of the other end.

[0083] The resin-sealed portion R3 is formed along the portion of the second side L12 between the fourth position P4 and the fifth position P5, with a predetermined width between them. The fifth position P5 is at the other end of the second side L12.

[0084] Figure 16 is a cross-sectional view along the line XVa-XVa in Figure 15. Figure 17 is a cross-sectional view along the line XVb-XVb in Figure 15. In the metal sealing portion R2, as shown in Figure 16, the sand layer 200b (metal layer) made of metal of the metal exposed portion 202 of the first part of the exterior material 200 and the sand layer 200b (metal layer) of the metal exposed portion 202 of the second part of the exterior material 200 are directly stacked on top of each other, or, as shown in Figure 17, the sand layer 200b (metal layer) of the metal exposed portion 202 of the first part of the exterior material 200 and the sand layer 200b (metal layer) of the metal exposed portion 202 of the second part of the exterior material 200 are stacked on top of each other via the positive electrode tab 120.

[0085] In the metal sealing portion R2, the first and second sand layers 200b are facing each other and overlapping, either directly or via the positive electrode tab 120. In a straight section of the overlapping portion (shown by the dotted line b along the first side L11, second side L12, and part of the third side L13 in Figure 15), the sand layers 200b (metal layers) are welded together, or the sand layers 200b (metal layers) are welded together with a part of the positive electrode tab 120, thus joining the metals and sealing the portion. In the metal sealing portion R2, there are no resin parts that come into contact with the outside air.

[0086] Figure 18 is a cross-sectional view along the line XVc-XVc in Figure 15. Figure 19 is a cross-sectional view along the line XVd-XVd in Figure 15. In the resin sealing portion R3, as shown in Figure 18, the heat-sealing layer 200c2 of the heat-sealing layer laminated portion 203 of the first part of the exterior material 200 and the heat-sealing layer 200c2 of the heat-sealing layer laminated portion 203 of the second part of the exterior material 200 are directly stacked on top of each other, or, as shown in Figure 19, the heat-sealing layer 200c2 of the heat-sealing layer laminated portion 203 of the first part of the exterior material 200 and the heat-sealing layer 200c2 of the heat-sealing layer laminated portion 203 of the second part of the exterior material 200 are stacked via the negative electrode tab 130. Furthermore, the heat-sealed layer 200c2 insulates the negative electrode tab 130 from the sand layer 200b (metal layer), preventing a short circuit and loss of battery function due to the negative electrode tab 130 being electrically connected to the positive electrode tab 120 (see Figure 17), which is in contact with the sand layer 200b (metal layer), via the sand layer 200b (metal layer).

[0087] The resin-sealed portion R3 is sealed by the first portion and the second portion having their heat-sealing layers 200c2 facing each other and overlapping, either directly or via the negative electrode tab 130, and either welding (heat-sealing) the heat-sealing layers 200c2 to each other in the overlapped portion, or by welding (heat-sealing) the heat-sealing layers 200c2 to each of the negative electrode tabs 130.

[0088] The battery according to the second embodiment has a larger metal sealing portion R2 in a part of the sealing portion R1 of the outer casing material 200 compared to the first embodiment. As a result, the battery according to the second embodiment can reduce the area of ​​the resin portion in contact with the outside air compared to the conventional method and the first embodiment, compared to the case where all overlapping edge regions are sealed by resin welding as in the conventional technology. Therefore, the battery according to the second embodiment can further reduce the amount of moisture permeation and further suppress the deterioration of battery performance.

[0089] <Manufacturing Method> The manufacturing method of the battery according to the second embodiment will now be described. An electrode body 110 is fabricated, and a positive electrode tab 120 and a negative electrode tab 130 are attached to fabricate a battery element 100. The outer casing material 200 shown in Figure 13 is prepared, and with the center line C1 passing through the center of the first side L1 as the axis of symmetry, two predetermined regions at positions that are symmetrical are processed so that they form a concave shape. In this way, two concave parts are formed in the outer casing material 200.

[0090] The outer material 200 is folded back along the center line C1, and the electrode body 110, to which the positive electrode tab 120 and negative electrode tab 130 are attached, is placed into the housing space formed by two opposing recesses. Then, the edge region around the recess of one of the folded first parts and the edge region around the recess of the other second part are overlapped.

[0091] Subsequently, the overlapping edge regions along the first side L11, the third side L13, and the straight portion of the overlapping edge region along a part of the second side L12 (dotted line b in Figure 15) are laser-welded. Alternatively, resistance welding or ultrasonic welding may be used instead of laser welding. Then, the remaining portion of the overlapping edge region along the second side L12 of the battery is heat-fused. This seals the three overlapping edge regions, completing the battery.

[0092] <Effects> As described above, the battery according to the second embodiment of the present invention can further reduce the amount of moisture permeation and further suppress the deterioration of battery performance.

[0093] <Second Modification> In the second embodiment described above, a first exterior material corresponding to the first portion above the center line C1 of the exterior material 200 in Figure 13 and a second exterior material corresponding to the second portion below the center line C1 in Figure 13 may be prepared, and recesses may be formed in each. A bag shape (bag form) may be formed by overlapping and sealing the edge regions around the recesses along the four sides of the first laminate film and the edge regions around the recesses along the four sides of the second laminate film. In this case, the exterior material 200 has its overlapping edge regions along its four sides (first side L11 to fourth side L14) sealed, forming a bag shape (bag form). In this case, the sealed portion R1 in which the overlapping edge regions along the four sides are sealed includes a metal sealed portion R2 and a resin sealed portion R3.

[0094] The metal sealing portion R2 is formed along the first side L11, the third side L13, and the portion between the third position P3 and the fourth position P4 of the second side L12, between position P5a of the fourth side L14 and the other end of the fourth side L14, with a predetermined width on the inside of these. The resin sealing portion R3 is formed along the portion between the fourth position P4 and the fifth position P5 of the second side L12, with a predetermined width between these. This second modification provides the same effects as the battery according to the second embodiment.

[0095] <<Third Embodiment>> A battery according to the third embodiment of the present invention will now be described. The battery according to the third embodiment differs from the battery according to the second embodiment in that, in the exterior material 200 of the second embodiment, the heat-sealing layer 200c2 of the heat-sealing layer laminated portion 203 is omitted, and instead a heat-sealable insulating member 131 (see Figure 22) equivalent to the heat-sealing layer 200c2 is arranged on each of the two sides of the negative electrode tab 130 so as to sandwich the negative electrode tab 130.

[0096] The following will focus on explaining these differences.

[0097] Figure 20 shows an example of the configuration of the exterior material 200 (before processing) before use in the battery according to the third embodiment. Figure 21 is a perspective view of the battery element 100.

[0098] As shown in Figure 20, the exterior material 200 has a rectangular planar shape. The exterior material 200 includes a main structural part 211 having the configuration described above and a metal exposed part 202 having the configuration described above.

[0099] In the exterior material 200, the main structural portion 211 is formed in a rectangular shape in the center when viewed from the direction normal to the exterior material 200. The rectangular main structural portion 211 is formed such that there is a gap between its outer peripheral edge and the outer peripheral edge of the exterior material 200. In the exterior material 200, the exposed metal portion 202 is formed in the region between the outer peripheral edge of the main structural portion 211 and the outer peripheral edge of the exterior material 200 when viewed from the direction normal to the exterior material 200.

[0100] As shown in Figure 21, heat-weldable insulating members 131 are provided on both sides of the negative electrode tab 130 of the battery element 100. A heat-weldable resin that is both insulating and heat-weldable can be used as the insulating member 131.

[0101] The sealing portion R1 includes a metal sealing portion R2 and a resin sealing portion R3. The metal sealing portion R2 is formed along the first side L11, the third side L13, and the portion between the third position P3 and the fourth position P4 of the second side L12, with a predetermined width inside these. The third position P3 is at one end of the second side L2, and the fourth position P4 is located at a predetermined distance from one end and the other end of the negative electrode tab 130 in the width direction, with the upper end being the upper end. The resin sealing portion R3 is formed along the portion between the fourth position P4 and the fifth position P5 of the second side L12, with a predetermined width between these. The fifth position P5 is at the other end of the second side L12.

[0102] Figures 22 and 23 are cross-sectional views illustrating the structure of the resin-sealed portion R3. In the resin-sealed portion R3, as shown in Figure 22, a portion of the metal exposed portion 202 of the first part of the exterior material 200 and a portion of the metal exposed portion 202 of the second part of the exterior material 200 are superimposed between them with an insulating member 131 in between, or, as shown in Figure 23, a portion of the metal exposed portion 202 of the first part and a portion of the metal exposed portion 202 of the second part are superimposed between them with an insulating member 131 and a negative electrode tab 130 in between. The insulating member 131 insulates between the sand layer 200b (metal layer) and the negative electrode tab 130, preventing the negative electrode tab 130 from being electrically connected to the positive electrode tab 120 which is in contact with the sand layer 200b (metal layer) via the sand layer 200b (metal layer), thereby preventing a short circuit and the battery from ceasing to function.

[0103] The battery according to the third embodiment has more metal sealing portions R2 in a part of the sealing portion R1 of the outer casing material 200 compared to the first embodiment. As a result, the battery according to the third embodiment can reduce the area of ​​the resin portion in contact with the outside air compared to the conventional method and the first embodiment, compared to the conventional method and the first embodiment, when the overlapping edge regions are all sealed by resin welding as in the conventional technology. Therefore, the battery according to the third embodiment can further reduce the amount of moisture permeation and further suppress the deterioration of battery performance.

[0104] <Manufacturing Method> The manufacturing method of the battery according to the third embodiment will now be described. An electrode body 110 is manufactured and a positive electrode tab 120 and a negative electrode tab 130 are attached. The outer casing material 200 shown in Figure 20 is prepared and processed so that two predetermined regions at positions that are symmetrical with respect to the center line C1 passing through the center of the first side L1 are each concave. In this way, two recesses are formed in the outer casing material 200.

[0105] The outer casing material 200 is folded back along the center line C1, and the electrode body 110, to which the positive electrode tab 120 and the negative electrode tab 130 with insulating members 131 on both sides are attached, is placed into the housing space formed by two opposing recesses. Then, the edge region around the recess of one of the folded first parts and the edge region around the recess of the other second part are overlapped.

[0106] Subsequently, the overlapping edge regions along the first side L11, the third side L13, and a portion of the overlapping edge region along the second side L12 of the battery, specifically the straight sections, are laser-welded. Alternatively, resistance welding or ultrasonic welding may be used instead of laser welding. Then, the remaining portion of the overlapping edge region along the second side L12 of the battery is heat-fused. This seals the three overlapping edges, completing the battery.

[0107] <Effects> As described above, the battery according to the third embodiment of the present invention can further reduce the amount of moisture permeation and further suppress the deterioration of battery performance.

[0108] <<Third Modification>> In the third embodiment described above, a first exterior material corresponding to the first portion above the center line C1 of the exterior material 200 in Figure 20 and a second exterior material corresponding to the second portion below the center line C1 in Figure 20 may be prepared, and recesses may be formed in each, and a bag shape (bag form) may be formed by overlapping and sealing the edge regions around the recesses along the four sides of the first laminate film and the edge regions around the recesses along the four sides of the second laminate film. In this case, the exterior material 200 has its overlapping edge regions along its four sides (first side L11 to fourth side L14) sealed, forming a bag shape (bag form). In this case, the sealed portion R1 in which the overlapping edge regions along the four sides are sealed includes a metal sealed portion R2 and a resin sealed portion R3.

[0109] The metal sealing portion R2 is formed along the first side L11, the third side L13, and the portion between the third position P3 and the fourth position P4 of the second side L12, between position P5a of the fourth side L14 and the other end of the fourth side L14, with a predetermined width on the inside of these. The resin sealing portion R3 is formed along the portion between the fourth position P4 and the fifth position P5 of the second side L12, with a predetermined width between these. This third modification provides the same effects as the battery according to the third embodiment.

[0110] <<Fourth Embodiment>> A battery according to the fourth embodiment of the present invention will now be described. The following description will focus on the differences from the first embodiment, and will omit explanations of points that overlap with the first embodiment.

[0111] Figure 24 shows an example of the configuration of the exterior material 200 before use in the battery according to the fourth embodiment. Figure 25 is a cross-sectional view along line XXIV-XXIV in Figure 24. As shown in Figure 24, the exterior material 200 has a rectangular planar shape. The exterior material 200 includes a main structural part 221, a first exposed metal part 222, a second exposed metal part 223, and a heat-sealed layer insulating part 224.

[0112] In the exterior material 200, the main structural part 221 is formed in a rectangular shape in the center when viewed from the direction normal to the exterior material 200. The main structural part 221 is formed so that there is a gap between its outer peripheral edge and the outer peripheral edge of the exterior material 200.

[0113] In the exterior material 200, the first exposed metal portion 222 is formed in all areas except for a portion of the region between the outer peripheral end of the main structural portion 221 and the outer peripheral end of the exterior material 200 (the region in which the second exposed metal portion 223 and the heat-sealed layer insulating portion 224 are formed), when viewed from the direction normal to the exterior material 200.

[0114] In the outer packaging material 200, the second exposed metal portion 223 is formed in a strip shape with a predetermined width along a portion of the second side L2 of the outer packaging material 200 when viewed from the normal direction of the outer packaging material 200. The strip-shaped second exposed metal portion 223 is formed to be symmetric with respect to the center line C1 passing through the center of the first side L1. As a result, when the outer packaging material 200 forms a bag shape, the second metal layer 200b2 (see Figure 25) of the second exposed metal portion 223 overlaps perfectly, allowing for efficient formation of the second metal sealing portion R12. Furthermore, the distance from the center line C1 along the outer edge of the second exposed metal portion 223 is formed to be greater than the width of the negative electrode tab 130. Furthermore, the second exposed metal portion 223 is formed straddling the center line C1, and it is sufficient that the width along the outer edge of the portion where the second metal layer 200b2 (see Figure 25) of the second exposed metal portion 223 overlaps when the outer packaging material 200 forms a bag shape is greater than the width of the negative electrode tab 130. The second exposed metal portion 223 does not necessarily need to be formed symmetrically with respect to the center line C1 as the axis of symmetry.

[0115] In the outer packaging material 200, the heat-sealed insulating layer 224 is formed with a predetermined width along the outer peripheral edge of the second exposed metal portion 223, excluding one outer side, when viewed from the normal direction of the outer packaging material 200. The heat-sealed insulating layer 224 is formed to be symmetrical with respect to the center line C1 passing through the center of the first side L1. As a result, when the outer packaging material 200 forms a bag shape, the heat-sealed insulating layer 200b3 of the heat-sealed insulating layer 224 overlaps perfectly, allowing for efficient formation of the resin sealing portion R3. Furthermore, the distance from the center line C1 along the outer peripheral edge of the heat-sealed insulating layer 224 is formed to be greater than the width of the negative electrode tab 130. Furthermore, the heat-sealed insulating layer portion 224 is formed straddling the center line C1, and it is sufficient that the width along the outer edge of the portion where the heat-sealed insulating layers 200b3 of the heat-sealed insulating layers 224 overlap when the outer packaging material 200 forms a bag shape is greater than the width of the negative electrode tab 130. The heat-sealed insulating layer 200b3 does not necessarily need to be formed symmetrically with respect to the center line C1 as the axis of symmetry.

[0116] As shown in Figure 25, the main structural part 221 of the exterior material 200 has a structure in which a base layer 200a, a first metal layer 200b1 which constitutes part of the sand layer 200b, and an insulating layer 200d are laminated. In the main structural part 221, the base layer 200a is formed on the surface of the first metal layer 200b1 that is located on the outside of the battery, and the insulating layer 200d is formed on the surface of the first metal layer 200b1 that is located on the inside of the battery. The insulating layer 200d only needs to have insulating properties, and may also have insulating and heat-fusible properties. The material that constitutes the insulating layer 200d can be the same material that constitutes the insulating layer 200c1. In addition, an inorganic insulating material (filler) may be appropriately added to the heat-fusible insulating layer 200b3 to improve mechanical and thermal properties. In order to suppress the amount of moisture permeation from the heat-fusible layer insulating part 224 to the heat-fusible insulating layer 200b3, the base layer 200a may be made of a resin with high barrier properties, and the thickness of the layer may be made thicker than usual.

[0117] The first exposed metal portion 222 has a single-layer structure consisting only of the first metal layer 200b1, which constitutes a part of the sand layer 200b. The first metal layer 200b1 is composed of metals such as Al, SUS, Ni, Cu, and Fe.

[0118] The second exposed metal portion 223 has a single-layer structure consisting only of the second metal layer 200b2, which constitutes the first other part of the sand layer 200b. The second metal layer 200b2 is composed of metals such as Al, SUS, Ni, Cu, and Fe. The metals constituting the first metal layer 200b1 and the metals constituting the second metal layer 200b2 may be the same type or different types.

[0119] The heat-sealed insulating layer 224 has a structure in which a heat-sealed insulating layer 200b3, which constitutes the second other part of the sand layer 200b, and a base layer 200a are laminated together. The base layer 200a is formed on the surface of the heat-sealed insulating layer 200b3 that is located on the outside of the battery. The heat-sealed insulating layer 200b3 insulates between the first metal layer 200b1 and the second metal layer 200b2. From the viewpoint of suppressing the amount of moisture permeating from the outside to the inside (in the direction of the arrow), it is preferable that the heat-sealed insulating layer 200b3 contains an inorganic insulating material (inorganic insulating filler) or the like.

[0120] Figure 26 is a plan view showing an example of the battery configuration according to the fourth embodiment. The outer casing material 200 is processed so that predetermined areas contained in the first and second parts, which are opposite each other on either side of the electrode body 110, are concave. The outer casing material 200 has an overlapping edge region around the concave part of the first part and an overlapping edge region around the concave part of the other second part. The outer casing material 200 has its overlapping edge regions along three sides of the battery (first side L11 to third side L13) sealed, forming a bag shape.

[0121] The sealing portion R1 is formed along the first side L11, the second side L12, and the third side L13, each having a predetermined width on its inner side.

[0122] The sealing portion R1 includes a first metal sealing portion R11, a second metal sealing portion R12, and a resin sealing portion R13.

[0123] The first metal sealing portion R11 is formed along the portion between the third position P3 and the sixth position P6 of the first side L11, the third side L13, and the second side L12, with a predetermined width on the inside of these. The sixth position P6 is located at a position separated by a first predetermined distance from one end of the negative electrode tab 130 in the width direction and the upper end of the other end.

[0124] The second metal sealing portion R12 is formed along the portion of the second side L12 between the fifth position P5 and the seventh position P7, with a predetermined width on the inside. The seventh position P7 of the second side L12 is located between one end of the negative electrode tab 130 in the width direction and the sixth position P6, at a distance of a second predetermined distance from the upper end of the other end of the negative electrode tab 130 in the width direction. The first predetermined distance is the distance from the upper end of the other end of the negative electrode tab 130 in the width direction to the side of the resin sealing portion R13 where the first metal sealing portion R11 is laser-welded (sixth position P6) as viewed from the resin sealing portion R13. The second predetermined distance is the distance from the upper end of the other end of the negative electrode tab 130 in the width direction to the side of the resin sealing portion R13 where the second metal sealing portion R12 is laser-welded (seventh position P7) as viewed from the resin sealing portion R13.

[0125] The resin sealing portion R13 is formed along the portion between the sixth position P6 and the seventh position P7 of the second side L12, with a predetermined width on the inside. In the width direction of the negative electrode tab 130, the resin sealing portion R13 has a side for the first metal sealing portion R11 to be laser-welded and a side for the second metal sealing portion R12 to be laser-welded.

[0126] In the first metal sealing portion R11, as shown in Figure 27, the first metal layer 200b1 of the first metal exposed portion 222 of the first part of the exterior material 200 and the first metal layer 200b1 of the first metal exposed portion 222 of the second part of the exterior material 200 are directly stacked on top of each other, or, although not shown, the first metal layer 200b1 of the first metal exposed portion 222 of the first part and the first metal layer 200b1 of the first metal exposed portion 222 of the second part are stacked on top of each other via the positive electrode tab 120.

[0127] In the second metal sealing portion R12, as shown in Figure 27, the second metal layer 200b2 of the first portion of the second metal exposed portion 223 and the second metal layer 200b2 of the second portion of the second metal exposed portion 223 are either directly stacked on top of each other, or the second metal layer 200b2 of the first portion of the second metal exposed portion 223 and the second metal layer 200b2 of the second portion of the second metal exposed portion 223 are stacked on top of each other via the negative electrode tab 130.

[0128] In the resin-sealed portion R13, as shown in Figure 27, the heat-sealable insulating layers 200b3 of the first and second portions are directly opposite each other and overlapped, and the heat-sealable insulating layers 200b3 are welded together at the overlapped portion to form a seal.

[0129] The battery according to the fourth embodiment has more metal sealing portions (first metal sealing portion R11 and second metal sealing portion R12) in a part of the sealing portion R1 of the outer casing material 200 compared to the first to third embodiments. As a result, the battery according to the fourth embodiment can reduce the area of ​​the resin portion in contact with the outside air compared to the conventional method and the first to third embodiments, compared to the conventional method and the first to third embodiments, where the overlapping edge regions are all sealed by resin welding as in the prior art. Therefore, the battery according to the fourth embodiment can further reduce the amount of moisture permeation and further suppress the deterioration of battery performance.

[0130] In the battery, a band-shaped heat-sealable insulating layer 200b3 of a predetermined width is formed surrounding the second metal layer 200b2 when viewed from the direction normal to the surface of the battery. This heat-sealable insulating layer 200b3 is provided between the first metal layer 200b1 and the second metal layer 200b2 to insulate them. As a result, the heat-sealable insulating layer 200b3 prevents the negative electrode tab 130, which is in contact with the second metal layer 200b2, from short-circuiting and becoming inoperable as a battery by being electrically connected to the positive electrode tab 120 via the second metal layer 200b2 and the first metal layer 200b1. In the fourth embodiment, the resin portion for insulation to prevent short circuits can be reduced compared to the first to third embodiments, so that the amount of moisture permeation can be further reduced and the deterioration of battery performance can be further suppressed.

[0131] In a battery, when viewed from the direction normal to the surface of the battery, it is preferable that the width d1 in the direction along the second side L12 of the portion where the heat-sealed insulating layer 200b3 is directly facing, overlapping, and welded is set to the minimum width that can ensure both insulating function and moisture permeability suppression function.

[0132] In the battery, when viewed from the direction normal to the surface of the battery, the width d2 in the direction along the second side L12 of the overlapping second metal exposed portions 223 is formed to be greater than the width of the negative electrode tab 130.

[0133] In the battery, when viewed from the direction normal to the surface of the battery, the width d3 in the direction along the fourth side L14 of the overlapping second metal exposed portions 223 is formed to be greater than the distance between the fifth position P5 and the metal bonding line, and less than or equal to the distance between the fifth position P5 and the outer peripheral edge of the main structure portion 221.

[0134] <Manufacturing Method> The manufacturing method of the battery according to the fourth embodiment will now be described. An electrode body 110 is manufactured and a positive electrode tab 120 and a negative electrode tab 130 are attached. An outer casing material 200 as shown in Figure 24 is prepared and processed so that two predetermined regions at positions that are symmetrical with respect to the center line C1 passing through the center of the first side L1 are each concave. In this way, two recesses are formed in the outer casing material 200.

[0135] The outer material 200 is folded back along the center line C1, and the electrode body 110, to which the positive electrode tab 120 and negative electrode tab 130 are attached, is placed into the housing space formed by two opposing recesses. Then, the edge region around the recess of one of the folded first parts and the edge region around the recess of the other second part are overlapped.

[0136] Subsequently, the linear portion of the edge region along the first side L11 (dotted line c in Figure 26) is laser-welded, and the third side L13 and the space between the third position P3 and the sixth position P6 of the second side L12 are laser-welded to form the first metal sealing portion R11. Next, the space between the fifth position P5 and the seventh position P7 of the second side L12 is laser-welded to form the second metal sealing portion R12, and a linear portion of the edge region along the third side L13 (dotted line c in Figure 26) is laser-welded. Note that resistance welding, ultrasonic welding, etc. may be applied instead of laser welding. After that, the remaining portion of the edge region, excluding the part corresponding to the third side L13, is heat-fused. As a result, the three sides of the overlapping edge regions are sealed, and the battery is completed.

[0137] <Effects> As described above, the battery according to the fourth embodiment of the present invention can further reduce the amount of moisture permeation and further suppress the deterioration of battery performance.

[0138] <<Fourth Modification>> In the fourth embodiment described above, a first exterior material corresponding to the first portion above the center line C1 of the exterior material 200 in Figure 24 and a second exterior material corresponding to the second portion below the center line C1 in Figure 24 are prepared, recesses are formed in each, and a bag shape (bag form) is formed by overlapping and sealing the edge regions around the recesses along the four sides of the first laminate film and the edge regions around the recesses along the four sides of the second laminate film. In this case, the exterior material 200 has its overlapping edge regions along its four sides (first side L11 to fourth side L14) sealed, forming a bag shape (bag form). In this case, the sealing portion R1 in which the overlapping edge regions along the four sides are sealed includes a first metal sealing portion R11, a second metal sealing portion R12, and a resin sealing portion R13.

[0139] The first metal sealing portion R11 is formed with a predetermined width on the inside of the portion between position P5b of the fourth side L14 and position P1, and along the portions of the first side L11, the third side L13, and the second side L12 between position P3 and position P6.

[0140] The second metal sealing portion R12 is formed along the portion of the second side L12 between the fifth position P5 and the seventh position P7, with a predetermined width on the inside. The seventh position P7 of the second side L12 is at one end of the negative electrode tab 130 in the width direction.

[0141] The resin sealing portion R13 is formed along the portion between the sixth position P6 and the seventh position P7 of the second side L12, with a predetermined width on the inside. This fourth modification provides the same effects as the battery according to the fourth embodiment.

[0142] <<Other Modifications>> The present invention is not limited to the above embodiments and modifications, and various modifications can be adopted within the scope of the present invention. The above embodiments and modifications can be combined with each other as long as they do not depart from the scope of the present invention.

[0143] The numerical values, structures, shapes, materials, raw materials, manufacturing processes, etc., given in each of the above embodiments and modifications are merely examples, and different numerical values, structures, shapes, materials, raw materials, manufacturing processes, etc., may be used as needed. The configurations, methods, processes, shapes, materials, numerical values, etc., of each of the above embodiments and modifications can be combined with each other as long as they do not deviate from the scope of the present invention.

[0144] In each of the above embodiments and modifications, the electrode body 110 of the battery element 100 is a stacked electrode body, but it may also be a wound electrode body in which the components of the electrode body are stacked and wound. Furthermore, the stacked electrode body may be a bellows-folded electrode stacked structure or a bipolar electrode structure.

[0145] In each of the above embodiments and modifications, the battery may have a structure in which the positive electrode tab 120 and the negative electrode tab 130 are swapped. In each of the above embodiments and modifications, the positive electrode tab 120 and the negative electrode tab 130 are led out from the battery element 100 in opposite directions and led out to the outside from opposite sides, but the positive electrode tab 120 and the negative electrode tab 130 may be led out from the battery element 100 in the same direction and led out to the outside from the same side. In each of the above embodiments and modifications, the positive electrode tab 120 and the negative electrode tab 130 may be led out from the battery element 100 in different directions other than opposite directions and led out to the outside from different sides. From the viewpoint of ease of welding, it is preferable that the positive electrode tab 120 and the negative electrode tab 130 are led out from the battery element 100 in opposite directions and led out to the outside from opposite sides.

[0146] The present invention can also take the following configuration.

[0147] [1] A battery comprising: an exterior material having a multi-layer laminated structure including metal and resin; a power generation element enclosed by the exterior material, the overlapping edge regions along the outer periphery being sealed to form a bag shape, and having a first power supply tab which is one of a positive electrode power supply tab and a second power supply tab which is the other of the positive electrode power supply tab and the negative electrode power supply tab connected to it; wherein the sealing portion, which is the sealed portion of the overlapping edge regions, includes a metal sealing portion in which opposing metals are welded together and a resin sealing portion in which opposing resins are welded together, the first power supply tab is led out to the outside from the metal sealing portion, and the second power supply tab is led out to the outside from the metal sealing portion or the resin sealing portion in an insulated state from the first power supply tab.

[0148] [2] The battery according to [1], wherein the exterior material includes a layer including at least a metal and an insulating portion, the layer including the metal and the insulating portion includes a first metal layer, a second metal layer, and an insulating portion that insulates the first metal layer and the second metal layer, the metal sealing portion includes a first metal sealing portion in which the first metal layers are welded facing each other, and a second metal sealing portion in which the second metal layers are welded facing each other, the first power supply tab is led out from the first metal sealing portion to the outside, and the second power supply tab is led out from the second metal sealing portion to the outside.

[0149] [3] A battery according to [1], wherein the exterior material includes a metal layer and a heat-weldable resin layer, the second power supply tab is led out from the resin sealing portion, the metal sealing portion includes a portion in which the metal layers are facing each other, directly overlapped and welded, and a portion in which the metal layers are facing each other, overlapped and welded via the first power supply tab, and the resin sealing portion includes a portion in which the heat-weldable resin layers are facing each other, directly overlapped and welded, and a portion in which the heat-weldable resin layers are facing each other, overlapped and welded via the second power supply tab, a battery.

[0150] [4] A battery according to [2], wherein the exterior material includes the metal layer and the heat-weldable resin layer, the first metal sealing portion includes a portion in which the first metal layers are facing each other, directly overlapped and welded, and a portion in which the first metal layers are facing each other, overlapped and welded via the first power supply tab, the second metal sealing portion includes a portion in which the second metal layers are facing each other, directly overlapped and welded, and a portion in which the second metal layers are facing each other, overlapped and welded via the second power supply tab, and the resin sealing portion includes a portion in which the heat-weldable resin layers are facing each other, directly overlapped and welded.

[0151] [5] A battery according to [1], wherein the second power supply tab is led out from the resin sealing portion to the outside, the resin sealing portion is formed only in the portion through which the second power supply tab passes and in its vicinity, and the sealing portion other than the resin sealing portion is formed by the metal sealing portion.

[0152] [6] A battery according to [4], wherein the resin sealing portion, which includes portions in which the heat-weldable resin layers face each other, are directly overlapped and welded together, is formed between the first metal sealing portion and the second metal sealing portion.

[0153] [7] In the battery described in [1], the second power supply tab is led out from the resin sealing portion, and the exterior material has a structure in which a metal layer, an insulating layer formed on a part of the inner surface of the metal layer, and a heat-weldable resin layer and a base layer formed on a part of the outer surface of the metal layer are laminated, and includes a metal exposed portion composed of a single metal layer, a main structural portion in which the base layer, the metal layer and the insulating layer are laminated, and a heat-weldable resin portion in which the metal layer and the heat-weldable resin layer are laminated, and the edge region which becomes the sealing portion has the metal exposed portions facing each other arranged therein, and a portion in which the metal layers of the metal exposed portions facing each other are directly overlapped and welded, and a portion in which the metal layers of the metal exposed portions facing each other are overlapped and welded via the first power supply tab, A battery in which the edge region that forms the sealing portion is arranged such that the heat-fusible resin portions are opposite to each other, and the portion in which the heat-fusible resin layers of the heat-fusible resin portions are directly overlapped and welded is formed, and the portion in which the heat-fusible resin layers of the heat-fusible resin portions are overlapped and welded via the second power supply tab is formed, and the main structural portion is arranged opposite to the power generation element on either side inside the edge region.

[0154] [8] In the battery described in [4], the exterior material has a structure in which a sand layer composed of the first metal layer, the second metal layer and the heat-weldable resin layer, an insulating layer formed on a part of the inner surface of the sand layer, and a base layer formed on a part of the outer surface of the sand layer are laminated, and includes a first metal exposed portion composed of a single first metal layer, a second metal exposed portion composed of a single second metal layer, a heat-weldable resin portion composed of two layers, the base layer and the heat-weldable resin layer, and a main structure portion composed of the base layer, the first metal layer and the insulating layer, wherein the edge region which becomes the first metal sealing portion has the first metal exposed portions facing each other, and a portion is formed in which the first metal layers of the first metal exposed portions facing each other are directly overlapped and welded, and a portion is formed in which the first metal layers of the first metal exposed portions facing each other are overlapped and welded via a first power supply tab, The edge region which forms the second metal sealing portion has the second metal exposed portions facing each other, and the portion in which the second metal layers of the opposing second metal exposed portions are directly overlapped and welded, and the portion in which the second metal layers of the opposing second metal exposed portions are overlapped and welded via the second power supply tab, and the main structural portion is arranged inside the edge region, with the power generation element in between.

[0155] [9] A battery according to [7] or [8], wherein the insulating layer is composed of a sheet-like insulating material, a coated insulating film, or a heat-weldable resin.

[0156]

[10] A battery according to [8], wherein the length of the second exposed metal portion along the width direction of the second power supply tab is greater than the width of the second power supply tab.

[0157]

[11] A battery according to [8], wherein the length of the second exposed metal portion in a direction perpendicular to the width direction of the second power supply tab is greater than the distance from the outer edge of the battery to the welded portion, and less than or equal to the distance from the outer edge of the battery to the outer edge of the main structure portion.

[0158]

[12] A battery as described in [8], wherein the width of the heat-sealable resin portion is set to the minimum width that can ensure both insulation and moisture permeability suppression.

[0159]

[13] A battery according to any one of [1] to

[12] , wherein the outer casing is formed by one outer casing being folded over, with each of the three edge regions excluding the folded edge overlapping each other and sealing to form a bag shape, or by two outer casings with the four edge regions of each of them overlapping each other and sealing to form a bag shape.

[0160]

[14] A battery as described in

[13] , wherein the first power supply tab and the second power supply tab extend from the power generation element in opposite directions and are led out to the outside from opposite sides.

[0161]

[15] A battery according to any one of [1] to

[14] , wherein the power generation element comprises an electrode body having a positive electrode side and a negative electrode side, and including a positive electrode, a negative electrode, and a solid electrolyte interposed between the positive electrode and the negative electrode, and the first power supply tab attached to the positive electrode side and the second power supply tab attached to the negative electrode side of the electrode body.

[0162] The technology according to this embodiment can reduce moisture permeation and suppress the deterioration of battery performance. By providing such technology, the present invention can contribute to "Goal 9 of the United Nations' Sustainable Development Goals (SDGs): Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation."

[0163] 100...Battery element, 110...Electrode body, 113...Positive electrode side layer, 114...Negative electrode side layer, 115...Solid electrolyte layer, 116...Positive electrode layer, 117...Positive electrode current collector layer, 118...Negative electrode layer, 119...Negative electrode current collector layer, 120...Positive electrode tab, 130...Negative electrode tab, 131...Insulating material, 200...Outer material, 200...Exposed metal part, 200a...Base layer, 200b... Sand layer, 200c...sealant layer, 201, 211, 221...main structural part, 202...metal exposed part, 203...heat-sealed layer laminated part, 222...first metal exposed part, 223...second metal exposed part, 224...heat-sealed layer insulating part, R1...sealing part, R2...metal sealing part, R11...first metal sealing part, R12...second metal sealing part, R3, R13...resin sealing part,

Claims

1. A battery comprising: an outer casing material having a multi-layer laminated structure including metal and resin; a power generation element enclosed by the outer casing material, wherein the overlapping edge regions along the outer periphery are sealed to form a bag shape, and a first power supply tab, which is one of a positive electrode power supply tab and a negative electrode power supply tab, and a second power supply tab, which is the other of the positive electrode power supply tab and the negative electrode power supply tab, are connected to the outer casing material; the sealing portion, which is the sealed portion of the overlapping edge regions, includes a metal sealing portion, which is formed by welding opposing metals together, and a resin sealing portion, which is formed by welding opposing resins together; the first power supply tab is led out from the metal sealing portion, and the second power supply tab is led out from the metal sealing portion or the resin sealing portion in an insulated state from the first power supply tab.

2. A battery according to claim 1, wherein the exterior material includes a layer including at least a metal and an insulating portion, the layer including the metal and the insulating portion includes a first metal layer, a second metal layer, and an insulating portion that insulates the first metal layer and the second metal layer, the metal sealing portion includes a first metal sealing portion in which the first metal layers are welded facing each other, and a second metal sealing portion in which the second metal layers are welded facing each other, the first power supply tab is led out from the first metal sealing portion, and the second power supply tab is led out from the second metal sealing portion.

3. A battery according to claim 1, wherein the exterior material includes a metal layer and a heat-weldable resin layer, the second power supply tab is led out from the resin sealing portion, the metal sealing portion includes a portion in which the metal layers are directly overlapped and welded facing each other, and a portion in which the metal layers are overlapped and welded facing each other via the first power supply tab, and the resin sealing portion includes a portion in which the heat-weldable resin layers are directly overlapped and welded facing each other, and a portion in which the heat-weldable resin layers are overlapped and welded facing each other via the second power supply tab.

4. A battery according to claim 2, wherein the exterior material includes the metal layer and the heat-weldable resin layer, the first metal sealing portion includes a portion in which the first metal layers are directly overlapped and welded facing each other, and a portion in which the first metal layers are overlapped and welded facing each other via the first power supply tab, the second metal sealing portion includes a portion in which the second metal layers are directly overlapped and welded facing each other, and a portion in which the second metal layers are overlapped and welded facing each other via the second power supply tab, and the resin sealing portion includes a portion in which the heat-weldable resin layers are directly overlapped and welded facing each other.

5. A battery according to claim 1, wherein the second power supply tab is led out from the resin sealing portion to the outside, the resin sealing portion is formed only in the portion through which the second power supply tab passes and in its vicinity, and the sealing portion other than the resin sealing portion is formed by the metal sealing portion.

6. A battery according to claim 4, wherein the resin sealing portion, which includes portions in which the heat-weldable resin layers are opposed to each other, directly overlapped and welded together, is formed between the first metal sealing portion and the second metal sealing portion.

7. The battery according to claim 1, wherein the second power supply tab is led out from the resin sealing portion, the exterior material has a structure in which a metal layer, an insulating layer formed on a part of the inner surface of the metal layer, and a heat-weldable resin layer and a base layer formed on a part of the outer surface of the metal layer are laminated, and includes a metal exposed portion composed of a single metal layer, a main structural portion in which the base layer, the metal layer and the insulating layer are laminated, and a heat-weldable resin portion in which the metal layer and the heat-weldable resin layer are laminated, the edge region which forms the sealing portion has metal exposed portions facing each other, and a portion in which the metal layers of the metal exposed portions facing each other are directly overlapped and welded, and a portion in which the metal layers of the metal exposed portions facing each other are overlapped and welded via the first power supply tab, A battery in which the edge region that forms the sealing portion is arranged such that the heat-fusible resin portions are opposite to each other, and the portion in which the heat-fusible resin layers of the heat-fusible resin portions are directly overlapped and welded is formed, and the portion in which the heat-fusible resin layers of the heat-fusible resin portions are overlapped and welded via the second power supply tab is formed, and the main structural portion is arranged opposite to the power generation element on either side inside the edge region.

8. The battery according to claim 4, wherein the exterior material has a structure in which a sand layer composed of the first metal layer, the second metal layer and the heat-weldable resin layer, an insulating layer formed on a part of the inner surface of the sand layer, and a base layer formed on a part of the outer surface of the sand layer are laminated, and includes a first metal exposed portion composed of a single first metal layer, a second metal exposed portion composed of a single second metal layer, a heat-weldable resin portion composed of two layers, the base layer and the heat-weldable resin layer, and a main structure portion composed of the base layer, the first metal layer and the insulating layer, wherein the edge region which becomes the first metal sealing portion has the first metal exposed portions facing each other, and a portion is formed in which the first metal layers of the first metal exposed portions facing each other are directly overlapped and welded, and a portion is formed in which the first metal layers of the first metal exposed portions facing each other are overlapped and welded via a first power supply tab, The edge region which forms the second metal sealing portion has the second metal exposed portions facing each other, and the portion in which the second metal layers of the opposing second metal exposed portions are directly overlapped and welded, and the portion in which the second metal layers of the opposing second metal exposed portions are overlapped and welded via the second power supply tab, and the main structural portion is arranged inside the edge region, with the power generation element in between.

9. A battery according to claim 8, wherein the insulating layer is composed of a sheet-like insulating material, a coated insulating film, or a heat-weldable resin.

10. A battery according to claim 8, wherein the length of the second exposed metal portion along the width direction of the second power supply tab is greater than the width of the second power supply tab.

11. A battery according to claim 8, wherein the length of the second exposed metal portion along the direction perpendicular to the width direction of the second power supply tab is greater than the distance from the outer edge of the battery to the welded portion, and less than or equal to the distance from the outer edge of the battery to the outer edge of the main structure portion.

12. A battery according to claim 8, wherein the width of the heat-sealable resin portion is set to the minimum width that can ensure both insulation and moisture permeability suppression.

13. A battery according to claim 1, wherein the outer casing is formed by one outer casing being folded over, with each of the three edge regions excluding the folded edge overlapping each other and sealing to form a bag shape, or by two outer casings being formed by the four edge regions of each being overlapping each other and sealing to form a bag shape.

14. A battery according to claim 13, wherein the first power supply tab and the second power supply tab extend from the power generation element in opposite directions and are led out to the outside from opposite sides.

15. A battery according to claim 1, wherein the power generation element comprises an electrode body having a positive electrode side and a negative electrode side, and including a positive electrode, a negative electrode, and a solid electrolyte interposed between the positive electrode and the negative electrode; and a first power supply tab attached to the positive electrode side and a second power supply tab attached to the negative electrode side of the electrode body.

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