Battery

Abstract

This battery comprises a power generating unit and a cover 1000 covering the power generating unit. The power generating unit includes a positive electrode layer 210, a negative electrode layer 230, and a solid electrolyte layer 220 between the positive electrode layer 210 and the negative electrode layer 230. At least one selected from the group consisting of the positive electrode layer 210, the solid electrolyte layer 220, and the negative electrode layer 230 includes a solid electrolyte containing a halogen. The cover 1000 includes a base material layer 100, a resin layer 110, and a metal layer 120 positioned between the base material layer 100 and the resin layer 110. The resin layer 110 is disposed on a side facing the power generation unit and includes a halogen-containing polymer.

Description

[Technical Field]

[0001] This disclosure relates to batteries. [Background technology]

[0002] Patent Document 1 discloses a laminate containing aluminum as a coating for batteries. It also discloses that hydrogen fluoride produced by the decomposition of lithium hexafluoride phosphate, a lithium salt used in non-aqueous electrolyte secondary batteries, corrodes the aluminum protective layer of the coating, causing delamination of the coating. Furthermore, as a method to prevent such delamination, it is disclosed that an intermediate layer is inserted between the protective layer and the adhesive layer. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2012-164680 [Overview of the project]

[0004] This disclosure provides a technology to improve the reliability of batteries.

[0005] A battery in one aspect of this disclosure is It comprises a power generation unit and a covering body that covers the power generation unit, The aforementioned power generation unit is The positive electrode layer, The negative electrode layer, The system comprises a solid electrolyte layer located between the positive electrode layer and the negative electrode layer, At least one selected from the group consisting of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer includes a solid electrolyte containing a halogen, The aforementioned covering body, A base layer and resin layer, The system comprises an intermediate layer located between the base material layer and the resin layer, The resin layer is positioned on the side facing the power generation unit and contains a halogen-containing polymer.

[0006] According to the present disclosure, the reliability of a battery can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a covering body 1000 in a first embodiment. [Figure 2] FIG. 2 is a diagram showing a schematic configuration of a battery 2000 in the first embodiment. [Figure 3] FIG. 3 is a diagram showing a schematic configuration of a covering body 3000 in a second embodiment. [Figure 4] FIG. 4 is a diagram showing a schematic configuration of a covering body 4000 in a third embodiment. [Figure 5] FIG. 5 is a cross-sectional view showing a schematic configuration of an example of a power generation element 5000. MODE FOR CARRYING OUT THE INVENTION

[0008] (Findings underlying the present disclosure) In a non-aqueous electrolyte secondary battery such as a lithium-ion secondary battery, the potential of the positive electrode rises to a high potential exceeding 4 V relative to lithium during the charging reaction of the battery. As a result of studies by the present inventor, it has been found that when a halogen-containing solid electrolyte is used as a constituent material of a solid battery and the battery is charged to such a high potential, halogen existing as an anion in the solid electrolyte is oxidized and released as halogen gas or hydrogen halide gas. Such gas has high corrosivity and easily reacts with metals or organic substances.

[0009] On the other hand, laminates produced by laminating various materials are widely used as battery covering bodies. Such a laminate is mainly composed of a base material layer for retaining shape, a protective layer for preventing intrusion of moisture or oxygen, and an adhesive layer for thermally welding laminates to each other when a plurality of laminates are stacked. Nylon is used for the base material layer, aluminum is used for the protective layer, and polyolefin resin is used for the adhesive layer.

[0010] Patent Document 1 discloses that hydrogen fluoride is generated by the decomposition of lithium salts in the electrolyte, which corrodes the materials in the laminate. It also discloses that an intermediate layer is placed between the protective layer and the adhesive layer to prevent corrosion by hydrofluoric acid as a countermeasure. Furthermore, Patent Document 1 discloses that a protective layer made of a resin such as epoxy resin is provided on the innermost surface of the barrier layer to absorb and adsorb hydrogen fluoride.

[0011] However, while the configuration disclosed in Patent Document 1 can prevent delamination of the adhesive layer by preventing corrosion of the aluminum protective layer, the inventors' research revealed that it cannot prevent corrosion of the adhesive layer itself.

[0012] In solid-state batteries, corrosive gases generated remain in high concentration as gases inside the laminated container, reacting with the polyolefin resin adhesive layer and significantly reducing its flexibility. As the reaction progresses, the adhesive layer is destroyed, and simultaneously, the internal protective layer is also eroded and destroyed by the corrosive gases. As a result, the laminated structure cannot maintain its insulating or gas barrier properties as a battery covering, and the reliability of the battery cannot be guaranteed.

[0013] This disclosure was made in view of the above-mentioned issues and aims to improve the reliability of batteries.

[0014] (Summary of one aspect of this disclosure) The battery relating to the first aspect of this disclosure is It comprises a power generation unit and a covering body that covers the power generation unit, The aforementioned power generation unit is The positive electrode layer, The negative electrode layer, The system comprises a solid electrolyte layer located between the positive electrode layer and the negative electrode layer, At least one selected from the group consisting of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer includes a solid electrolyte containing a halogen, The aforementioned covering body, A base layer and resin layer, The system comprises a metal layer located between the base material layer and the resin layer, The resin layer is positioned on the side facing the power generation unit and contains a halogen-containing polymer.

[0015] According to the first embodiment, direct contact between corrosive gases and the insulating or gas barrier layer of the coating can be prevented. Therefore, the reliability of the battery can be improved.

[0016] In a second aspect of this disclosure, for example, in the battery according to the first aspect, the metal layer may include at least one selected from the group consisting of aluminum, aluminum alloys, and stainless steel.

[0017] In a third aspect of this disclosure, for example, in the battery according to the first aspect, the metal layer may include aluminum.

[0018] In a fourth aspect of this disclosure, for example, in a battery according to any one of the first to third aspects, the ionic radius of the halogen contained in the resin layer may be the same as or smaller than the ionic radius of the halogen contained in the solid electrolyte.

[0019] In a fifth aspect of this disclosure, for example, a battery according to any one of the first to fourth aspects may further include a primer layer located between the metal layer and the resin layer.

[0020] In a sixth aspect of this disclosure, for example, in a battery according to the fifth aspect, the primer layer may include at least one selected from the group consisting of nitrogen, silicon, sulfur, and titanium.

[0021] In a seventh aspect of this disclosure, for example, in a battery according to the fifth aspect, the primer layer may include at least one selected from the group consisting of silane coupling agents, titanate coupling agents, polyimides, polyamides, and polymers having sulfonic acid groups.

[0022] In the eighth aspect of this disclosure, for example, in a battery according to any one of the first to seventh aspects, the resin layer may further contain a halogen-free polymer.

[0023] In a ninth aspect of this disclosure, for example, in a battery according to any one of the first to eighth aspects, the halogen-containing polymer may be a polymer containing a fluorine atom or a chlorine atom.

[0024] In a tenth aspect of this disclosure, for example, in a battery according to the ninth aspect, the halogen-containing polymer is a fluorine-containing polymer, and the fluorine-containing polymer may include at least one selected from the group consisting of tetrafluoroethylene, vinylidene fluoride, perfluoroalkyl vinyl ether, hexafluoropropylene, and chlorotrifluoroethylene.

[0025] In an eleventh aspect of this disclosure, for example, in the battery according to the ninth aspect, the halogen-containing polymer is a fluorine-containing polymer, and the fluorine-containing polymer may include at least one selected from the group consisting of tetrafluoroethylene, vinylidene fluoride, and hexafluoropropylene.

[0026] In a twelfth aspect of this disclosure, for example, in a battery according to the ninth aspect, the halogen-containing polymer is a fluorine-containing polymer, and the fluorine-containing polymer may include at least one selected from the group consisting of fluorinated polyethylene, fluorinated polypropylene, tetrafluoroethylene-hexafluoropropylene copolymer, polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, polychlorotrifluoroethylene, fluororubber, fluorosilicone rubber, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer, tetrafluoroethylene-propylene rubber, and tetrafluoroethylene-perfluoromethyl vinyl ether rubber.

[0027] In a thirteenth aspect of this disclosure, for example, in a battery according to any one of the first to twelfth aspects, the halogen concentration in the resin layer may be continuously or gradually increasing from the metal layer side to the opposite side.

[0028] According to the second to thirteenth embodiments, direct contact between corrosive gases and the insulating or gas barrier layer of the coating can be prevented. This improves the reliability of the battery.

[0029] The battery covering according to the 14th aspect of this disclosure is A base layer and resin layer, The system comprises a metal layer located between the base material layer and the resin layer, The resin layer contains a halogen-containing polymer.

[0030] In a 15th aspect of this disclosure, for example, the battery coating according to the 14th aspect may further include a primer layer located between the metal layer and the resin layer.

[0031] In a sixteenth aspect of this disclosure, for example, in a battery covering according to a fourteenth or fifteenth aspect, the metal layer may include aluminum.

[0032] In a 17th aspect of this disclosure, for example, in a battery coating according to any one of the 14th to 16th aspects, the halogen-containing polymer may be a polymer containing a fluorine atom or a chlorine atom.

[0033] In the eighteenth aspect of this disclosure, for example, in the battery coating according to the seventeenth aspect, the halogen-containing polymer is a fluorine-containing polymer, and the fluorine-containing polymer may include at least one selected from the group consisting of tetrafluoroethylene, vinylidene fluoride, perfluoroalkyl vinyl ether, and hexafluoropropylene and chlorotrifluoroethylene.

[0034] In a 19th aspect of this disclosure, for example, in a battery coating according to the 17th aspect, the halogen-containing polymer is a fluorine-containing polymer, and the fluorine-containing polymer may include at least one selected from the group consisting of tetrafluoroethylene, vinylidene fluoride, hexafluoropropylene, and copolymers thereof.

[0035] In a 20th aspect of this disclosure, for example, in a battery according to the 17th aspect, the halogen-containing polymer is a fluorine-containing polymer, and the fluorine-containing polymer may include at least one selected from the group consisting of fluorinated polyethylene, fluorinated polypropylene, tetrafluoroethylene-hexafluoropropylene copolymer, polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, polychlorotrifluoroethylene, fluorosilicone rubber, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer, tetrafluoroethylene-propylene rubber, and tetrafluoroethylene-perfluoromethyl vinyl ether rubber.

[0036] According to embodiments 14 to 20, when applied to a battery, direct contact between corrosive gases inside the battery and the insulating or gas barrier layer of the coating can be prevented. Therefore, the coating according to this disclosure can improve the reliability of the battery.

[0037] Embodiments of this disclosure will be described below with reference to the drawings. This disclosure is not limited to the embodiments described below.

[0038] (Embodiment) Figure 1 is a cross-sectional view showing the schematic configuration of the covering 1000 in Embodiment 1.

[0039] The coating 1000 in Embodiment 1 comprises a base layer 100, a resin layer 110, and a metal layer 120 located between the base layer 100 and the resin layer 110. The resin layer 110 contains a halogen-containing polymer. The resin layer 110 is positioned on the side facing the power generation section of the battery. The resin layer 110 is a layer containing resin. The resin layer 110 contains a halogen-containing polymer.

[0040] The material of the base layer 100 may be polyester resin, nylon resin, etc. The polyester resin and nylon resin materials may be stretched. Examples of polyester resins include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, copolymer polyester, and polycarbonate. Examples of nylon resins include nylon 6, nylon 6,6, copolymer of nylon 6,6 and nylon 6, nylon 6,10, and polyamide resins such as polymetaxylylene adipamide (MXD6). The thickness of the base layer 100 may be 5 μm or more and 40 μm or less.

[0041] Halogen-containing polymers contain halogen atoms in their structure. The halogen atoms contained in the halogen-containing polymer may be fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc. The halogen-containing polymer contained in the resin layer 110 may be a polymer containing fluorine atoms or chlorine atoms. The ionic radius of the halogen contained in the resin layer 110 may be the same as or smaller than the ionic radius of the halogen contained in the solid electrolyte.

[0042] With the above configuration, corrosion of the metal layer 120 by corrosive gases can be suppressed more effectively. The smaller the ionic radius of the halide ion, the greater its electronegativity and the stronger its bond to the carbon in the polymer chain. In other words, if the ionic radius of the halide ions contained in the resin layer 110 is smaller than the ionic radius of the halide ions contained in the generated corrosive gas, the halide ions in the corrosive gas are less likely to react with the polymer in the resin layer 110. Furthermore, even if the ionic radii are the same, i.e., the same element, the reaction is less likely to occur because the driving force for the reaction is small.

[0043] The metal layer 120 may contain at least one metallic element selected from the group consisting of aluminum and iron. The metal layer 120 may contain at least one selected from aluminum, aluminum alloy, and stainless steel. The aluminum alloy may be an alloy mainly composed of aluminum. The metal layer 120 may contain aluminum. With the above configuration, sufficient strength, lightness, and economy can be achieved as a battery coating 1000. The thickness of the metal layer 120 may be 5 μm or more and 40 μm or less. The metal layer 120 is typically made of metal foil.

[0044] The halogen-containing polymer in the structure of the coating 1000 has a higher softening point and is harder at room temperature compared to a halogen-free polymer. Therefore, if the resin layer 110 is located inside the metal layer 120, i.e., on the side facing the power generation part of the battery, it will hinder adhesion between the coatings 1000 when multiple coatings 1000 are stacked. In the resin layer 110, the halogen concentration may be continuously or gradually increasing from the metal layer 120 side to the opposite side. The halogen concentration refers to the amount of halogen element contained in the resin layer 110. The amount of halogen element may be measured by elemental analysis from the surface direction to the depth direction using a glow discharge emission spectrometer.

[0045] Figure 2 shows a schematic configuration of the battery 2000 in Embodiment 1.

[0046] The battery 2000 in Embodiment 1 comprises a covering 1000, a positive electrode current collector 200, a positive electrode layer 210, a solid electrolyte layer 220, a negative electrode layer 230, and a negative electrode current collector 240. The solid electrolyte layer 220 is disposed between the positive electrode layer 210 and the negative electrode layer 230. The positive electrode layer 210 is a layer containing a positive electrode active material. The negative electrode layer 230 is a layer containing a negative electrode active material. The positive electrode layer 210, the solid electrolyte layer 220, and the negative electrode layer 230 constitute the power generation section of the battery 2000. At least one of the positive electrode layer 210, the solid electrolyte layer 220, and the negative electrode layer 230 contains a solid electrolyte containing a halogen. The solid electrolyte containing a halogen may be a halide solid electrolyte or a sulfide solid electrolyte containing a halogen. The positive electrode current collector 200 and the negative electrode current collector 240 are electrically in contact with the positive electrode layer 210 and the negative electrode layer 230, respectively. The covering 1000 constitutes the container of the battery 2000. Specifically, the resin layer 110 of the upper covering 1000 and the resin layer 110 of the lower covering 1000 are facing each other at their ends and heat-pressed together to form the container of the battery 2000. The power generation unit of the battery 2000 is housed inside the container made of the covering 1000. As a result, the power generation unit of the battery 2000 is covered by the covering 1000.

[0047] With the above configuration, a highly reliable battery can be realized. By arranging the resin layer 110 on the side facing the power generation unit, contact between corrosive gases generated during battery charging and the metal layer 120 can be reduced, thereby suppressing the deterioration of the metal layer 120. In this embodiment, the resin layer 110 is in contact with the atmosphere inside the container made of the covering 1000.

[0048] Figure 3 shows a schematic configuration of the covering 3000 in Embodiment 2. The covering 3000 allows for the construction of a battery container similar to that in Figure 2 (Embodiment 1). Furthermore, unless otherwise specified, the configuration may be the same as in Embodiment 1.

[0049] The coating 3000 in Embodiment 2 comprises a base layer 100, a resin layer 110, a metal layer 120 located between the base layer 100 and the resin layer 110, and a primer layer 300 located between the metal layer 120 and the resin layer 110. The resin layer 110 contains a halogen-containing polymer.

[0050] With the above configuration, the adhesion between the resin layer 110 and the metal layer 120 can be improved, thereby increasing the reliability of the battery.

[0051] Halogen-containing polymers, especially those containing fluorine, exhibit excellent chemical durability but have weak interactions with other substances. Therefore, they are difficult to bond to dissimilar materials such as metals or ceramics. To improve adhesion, a primer layer can be placed as a layer with high bonding properties to both materials. Ideally, the primer layer should be uniformly distributed in the planar direction without pinholes.

[0052] The primer layer 300 may contain at least one element selected from the group consisting of nitrogen, silicon, sulfur, and titanium. This configuration improves the adhesion between the resin layer 110 and the metal layer 120, thereby increasing the reliability of the battery. These elements can form bonds that connect inorganic and organic materials, thus improving adhesion.

[0053] The primer layer 300 may contain at least one selected from the group consisting of silane coupling agents, titanate coupling agents, polyimides, polyamides, and polymers having sulfonic acid groups. The thickness of the primer layer 300 may be 10 nm or more and 10 μm or less. With the above configuration, the adhesion between the resin layer 110 and the metal layer 120 can be improved, thereby increasing the reliability of the battery.

[0054] Figure 4 shows a schematic configuration of the covering 4000 in Embodiment 3. The covering 4000 allows for the construction of a battery container similar to that in Figure 2 (Embodiment 1). Furthermore, unless otherwise specified, the configuration may be the same as in Embodiment 1.

[0055] The coating 4000 in Embodiment 3 comprises a base layer 100, a resin layer 400, and a metal layer 120 located between the base layer 100 and the resin layer 400. The resin layer 400 includes a halogen-free polymer 410 and a halogen-containing polymer 420.

[0056] With the above configuration, the adhesion between multiple coatings when stacking them can be improved, thereby increasing the reliability of the battery.

[0057] The halogen-containing polymer 420 has high melting and softening points and low interaction with other materials, making it relatively difficult to bond multiple coatings together when layering them. Therefore, by placing a polymer containing not only the halogen-containing polymer 420 but also a halogen-free polymer 410 in the resin layer 400, the halogen-free polymer 410, which has a lower softening point, can be melted during the heat welding of the coatings, thereby improving adhesion. This configuration allows for a balance between adhesion and chemical durability. The larger the volume ratio of the halogen-containing polymer 420, the better the chemical durability, and the larger the volume ratio of the halogen-free polymer 410, the better the adhesion.

[0058] The halogen-free polymer 410 may be a thermoplastic resin.

[0059] The thermoplastic resin may be, for example, polyolefin resin, acrylic resin, polystyrene resin, vinyl chloride resin, silicone resin, polyamide resin, polyimide resin, fluorinated hydrocarbon resin, polyether resin, rubber, etc. The polyolefin resin may be polyethylene resin, polypropylene resin, etc. The rubber may be butadiene rubber, isoprene rubber, styrene-butadiene rubber (SBR), styrene-butadiene-styrene copolymer (SBS), styrene-ethylene-butadiene-styrene copolymer (SEBS), ethylene-propylene rubber, butyl rubber, chloroprene rubber, and acrylonitrile-butadiene rubber, etc. The thermosetting resin may be urethane resin, epoxy resin, etc. The resin may be used alone or in combination of two or more types. With the above configuration, resistance to corrosive gases and adhesion of the coating 4000 can be achieved simultaneously.

[0060] Furthermore, the shape or structure of the halogen-free polymer 410 and the halogen-containing polymer 420 are not particularly specified. Particles made of the halogen-free polymer 410 may be dispersed in the halogen-containing polymer 420, or they may each have a randomly intermingled structure.

[0061] The following describes specific examples of the resin layer 110 of the coating in Embodiments 1 and 2, and the resin layer 400 of the coating in Embodiment 3. The resin layers 110 and 400 contain a halogen-containing polymer. The halogen-containing polymer may be a polymer resin containing fluorine atoms or chlorine atoms. With the above configuration, resistance to corrosive gases can be achieved.

[0062] The fluorine-containing polymer may include at least one selected from the group consisting of tetrafluoroethylene (TFE), vinylidene fluoride, perfluoroalkyl vinyl ether, hexafluoropropylene (HFP), and chlorotrifluoroethylene. With this configuration, both resistance to corrosive gases and moldability can be achieved.

[0063] Furthermore, the fluorine-containing polymer may include at least one selected from the group consisting of tetrafluoroethylene, vinylidene fluoride, and hexafluoropropylene. With the above configuration, both resistance to corrosive gases and moldability can be achieved.

[0064] The fluorine-containing polymer may also contain fluororubber. Examples of fluororubber include fluorosilicone rubber, vinylidene fluoride-hexafluoropropylene copolymer (FKM), vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer, tetrafluoroethylene-propylene rubber (FEPM), and tetrafluoroethylene-perfluoromethyl vinyl ether rubber (FFKM). The fluorine-containing polymer may include at least one selected from the group consisting of fluorinated polyethylene, fluorinated polypropylene, tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), polychlorotrifluoroethylene (PCTFE), fluororubber, fluorosilicone rubber, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer, tetrafluoroethylene-propylene rubber (FEPM), and tetrafluoroethylene-perfluoromethyl vinyl ether rubber (FFKM). With the above configuration, resistance to corrosive gases can be achieved.

[0065] The resin layers 110 and 400 are formed by surface-modifying the metal layer 120. With the above configuration, both resistance to corrosive gases and moldability can be achieved. When manufacturing the coating 4000, the resin layers 110 and 400 may be formed by contacting the surface of the coating 4000 with a halogen-containing gas such as fluorine gas, hydrogen fluoride gas, chlorine gas, or hydrogen chloride gas, thereby introducing fluorine or chlorine into the polymer on the surface of the metal layer 120. The surface of the metal layer 120 may be modified by immersing the coating 4000 in a solution containing at least one selected from the group consisting of fluoride ions and chloride ions.

[0066] The halogen concentration in the resin layers 110 and 400 has a structure in which it becomes progressively or stepwise more concentrated from the metal layer 120 side to the opposite side. With this configuration, both resistance to corrosive gases and moldability can be achieved. The thickness of the resin layers 110 and 400 may be between 1 nm and 10,000 nm.

[0067] The following describes a specific example of a power generation element 5000 when a battery is constructed that includes a covering selected from the group consisting of coverings of Embodiments 1 to 3. The battery comprises a power generation element 5000 and a covering selected from the group consisting of coverings of Embodiments 1 to 3 that covers the power generation element 5000.

[0068] The main surface area of ​​the power generation element 5000 is, for example, 1 cm² for batteries used in portable electronic devices such as smartphones and digital cameras. 2 More than 100cm 2 The following is also acceptable: Alternatively, the main surface area of ​​the power generation element 5000 may be 100 cm² as a battery for powering large mobile devices such as electric vehicles. 2 More than 1000cm 2 The following is also acceptable.

[0069] Figure 5 is a cross-sectional view showing a schematic configuration of an example of a power generation element 5000.

[0070] The power generation element 5000 comprises a positive electrode layer 520, a negative electrode layer 540, and an electrolyte layer 530.

[0071] The electrolyte layer 530 is placed between the positive electrode layer 520 and the negative electrode layer 540. In this case, the electrolyte layer 530 may be a solid electrolyte layer containing a solid electrolyte. At least one selected from the group consisting of the positive electrode layer 520, the electrolyte layer 530, and the negative electrode layer 540 contains a solid electrolyte containing a halogen. The solid electrolyte containing a halogen may be a halide solid electrolyte or a sulfide solid electrolyte containing a halogen.

[0072] With the above configuration, the battery can be configured as a solid-state battery. The solid-state battery may be a rechargeable battery such as an all-solid-state lithium-ion secondary battery.

[0073] Furthermore, the power generation element 5000 may further include a positive electrode current collector 510 and a negative electrode current collector 550.

[0074] The positive electrode current collector 510 is positioned in contact with the positive electrode layer 520.

[0075] Furthermore, a portion of the positive electrode current collector 510 may be exposed outside the covering 1000 as a positive electrode terminal.

[0076] The negative electrode current collector 550 is positioned in contact with the negative electrode layer 540.

[0077] Furthermore, a portion of the negative electrode current collector 550 may be exposed outside the covering 1000 as a negative electrode terminal.

[0078] As described above, as shown in Figure 5, the power generation element 5000 may be a single power generation element (a single cell).

[0079] As the positive electrode current collector 510, a porous or non-porous sheet or film made of a metallic material such as aluminum, stainless steel, titanium, or their alloys may be used. Aluminum and its alloys are inexpensive and easy to thin. The sheet or film may be a metal foil or a mesh. The thickness of the positive electrode current collector 510 may be 1 μm or more and 30 μm or less. If the thickness of the positive electrode current collector 510 is 1 μm or more, sufficient mechanical strength can be ensured. If the thickness of the positive electrode current collector 510 is 30 μm or less, sufficient energy density of the battery can be ensured.

[0080] The positive electrode layer 520 is a layer containing the positive electrode active material. The positive electrode layer 520 may contain a solid electrolyte. The solid electrolyte of the positive electrode layer 520 may contain a halogen-containing solid electrolyte. The halogen-containing solid electrolyte may be a halide solid electrolyte or a halogen-containing sulfide solid electrolyte.

[0081] As positive electrode active materials, for example, lithium-containing transition metal oxides, transition metal fluorides, polyanions and fluorinated polyanion materials, and transition metal sulfides, transition metal oxyfluorides, transition metal oxysulfides, and transition metal oxynitrides can be used. In particular, when lithium-containing transition metal oxides are used as positive electrode active material particles, manufacturing costs can be reduced and the average discharge voltage can be increased. It is especially preferable to use Li(NiCoAl)O2 as the lithium-containing transition metal oxide. When Li(NiCoAl)O2 is used, the energy density of the battery can be further increased.

[0082] Halide solid electrolytes are represented, for example, by the following compositional formula (1). In compositional formula (1), α, β, and γ are each independently greater than 0. M contains at least one element selected from the group consisting of metallic elements and metalloid elements other than Li. X contains at least one element selected from the group consisting of F, Cl, Br, and I.

[0083] Li α M β X γ ...(1)

[0084] Metalloid elements include B, Si, Ge, As, Sb, and Te. Metallic elements include all elements in groups 1 through 12 of the periodic table except hydrogen, and all elements in groups 13 through 16 except B, Si, Ge, As, Sb, Te, C, N, P, O, S, and Se. Metallic elements are a group of elements that can become cations when forming halogen compounds and inorganic compounds.

[0085] As the halide solid electrolyte, Li₃YX₆, Li₂MgX₄, Li₂FeX₄, Li(Al,Ga,In)X₄, Li₃(Al,Ga,In)X₆ and the like may be used. "(Al,Ga,In)" is synonymous with "at least one selected from the group consisting of Al, Ga and In". A typical composition of Li₃YX₆ is Li₃YBr₂Cl₄.

[0086] The thickness of the positive electrode layer 520 may be 10 µm or more and 500 µm or less. When the thickness of the positive electrode layer 520 is 10 µm or more, a sufficient energy density of the battery can be secured. When the thickness of the positive electrode layer 520 is more than 500 µm, the battery can be operated at high output.

[0087] The electrolyte layer 530 is, for example, a solid electrolyte layer containing a solid electrolyte. The solid electrolyte may be, for example, a halogen-containing solid electrolyte. The solid electrolyte may contain the above-mentioned halide solid electrolyte. The solid electrolyte may contain a sulfide solid electrolyte.

[0088] As the sulfide solid electrolyte, for example, Li₂S-P₂S₅, Li₂S-SiS₂, Li₂S-B₂S₃, Li₂S-GeS₂, Li 3.25 Ge 0.25 P 0.75 S₄, Li 10 GeP₂S 12 and the like may be used. Further, to these, LiX (X: F, Cl, Br, I), Li₂O, MO z , Li y MO z (M is any one of P, Si, Ge, B, Al, Ga, In, Fe, Zn) (y and z are natural numbers) and the like may be added. As the halogen-containing sulfide solid electrolyte, for example, Li₂S-P₂S₅, Li₂S-SiS₂, Li₂S-B₂S₃, Li₂S-GeS₂, Li 3.25 Ge 0.25 P 0.75 S₄, Li 10 GeP₂S 12LiX(X:F,Cl,Br,I) may be added to the above. Li2S-P2S5 has high ionic conductivity and is not easily reduced at low potentials. For this reason, using Li2S-P2S5 makes it easy to create a battery.

[0089] The thickness of the electrolyte layer 530 may be between 1 μm and 100 μm. When the thickness of the electrolyte layer 530 is 1 μm or more, the positive electrode layer 520 and the negative electrode layer 540 can be reliably insulated. When the thickness of the electrolyte layer 530 is 100 μm or less, the battery can operate at high power.

[0090] The negative electrode layer 540 is a layer containing the negative electrode active material. The negative electrode layer 540 may contain a solid electrolyte. The solid electrolyte of the negative electrode layer 540 may contain a halogen-containing solid electrolyte. The halogen-containing solid electrolyte may be a halide solid electrolyte or a halogen-containing sulfide solid electrolyte.

[0091] The negative electrode active material may be, for example, a material that intercepts and releases metal ions. The negative electrode active material may be, for example, a material that intercepts and releases lithium ions. Examples of negative electrode active materials include lithium metal, metals or alloys that react with lithium, carbon, transition metal oxides, and transition metal sulfides. Examples of carbon include graphite, or non-graphite carbon such as hard carbon or coke. Examples of transition metal oxides include CuO and NiO. Examples of transition metal sulfides include copper sulfide represented by CuS. Examples of metals or alloys that react with lithium include silicon compounds, tin compounds, and alloys of aluminum compounds with lithium. When carbon is used, manufacturing costs can be reduced and the average discharge voltage can be increased.

[0092] The thickness of the negative electrode layer 540 may be between 10 μm and 500 μm. If the thickness of the negative electrode layer 540 is 10 μm or more, sufficient energy density of the battery can be ensured. If the thickness of the negative electrode layer 540 is 500 μm or less, the battery can operate at high power.

[0093] As the negative electrode current collector 550, a porous or non-porous sheet or film made of a metallic material such as stainless steel, nickel, copper, or their alloys may be used. Copper and its alloys are inexpensive and easy to thin. The sheet or film may be a metal foil or a mesh. The thickness of the negative electrode current collector 550 may be 1 μm or more and 30 μm or less. If the thickness of the negative electrode current collector 550 is 1 μm or more, sufficient mechanical strength is ensured. If the thickness of the negative electrode current collector 550 is 30 μm or less, sufficient energy density of the battery is ensured.

[0094] At least one of the positive electrode layer 520, the electrolyte layer 530, and the negative electrode layer 540 may contain an oxide solid electrolyte for the purpose of increasing ionic conductivity. Examples of oxide solid electrolytes include NASICON-type solid electrolytes represented by LiTi2(PO4)3 and its elemental substitutions, (LaLi)TiO3-based perovskite-type solid electrolytes, and Li 14 ZnGe4O 16 , LISICON-type solid electrolytes represented by Li4SiO4, LiGeO4 and their elemental substitutions, Li7La3Zr2O 12 Garnet-type solid electrolytes, such as those represented by elemental substitutions thereof, Li3N and its H-substituted derivatives, and Li3PO4 and its N-substituted derivatives can be used.

[0095] At least one of the positive electrode layer 520, the electrolyte layer 530, and the negative electrode layer 540 may contain an organic polymer solid electrolyte for the purpose of increasing ionic conductivity. As the organic polymer solid electrolyte, for example, a compound of a polymer compound and a lithium salt can be used. The polymer compound may have an ethylene oxide bond. Having an ethylene oxide bond allows for a higher content of lithium salt, which can further increase ionic conductivity. As lithium salts, LiPF6, LiBF4, LiSbF6, LiAsF6, LiSO3CF3, LiN(SO2CF3)2, LiN(SO2C2F5)2, LiN(SO2CF3)(SO2C4F9), LiC(SO2CF3)3, etc. As the lithium salt, one lithium salt selected from these may be used alone. Alternatively, a mixture of two or more lithium salts selected from these may be used.

[0096] At least one of the positive electrode layer 520, the electrolyte layer 530, and the negative electrode layer 540 may contain a non-aqueous electrolyte solution, a gel electrolyte, or an ionic liquid for the purpose of facilitating the transfer of lithium ions and improving the output characteristics of the battery. The non-aqueous electrolyte solution includes a non-aqueous solvent and a lithium salt dissolved in the non-aqueous solvent. As the non-aqueous solvent, cyclic carbonate ester solvents, linear carbonate ester solvents, cyclic ether solvents, linear ether solvents, cyclic ester solvents, linear ester solvents, fluorine solvents, etc., can be used. Examples of cyclic carbonate ester solvents include ethylene carbonate, propylene carbonate, and butylene carbonate. Examples of linear carbonate ester solvents include dimethyl carbonate, ethyl methyl carbonate, and diethyl carbonate. Examples of cyclic ether solvents include tetrahydrofuran, 1,4-dioxane, and 1,3-dioxolane. Examples of linear ether solvents include 1,2-dimethoxyethane and 1,2-diethoxyethane. Examples of cyclic ester solvents include γ-butyrolactone. Examples of linear ester solvents include methyl acetate. Examples of fluorine solvents include fluoroethylene carbonate, methyl fluoropropionate, fluorobenzene, fluoroethyl methyl carbonate, and fluorodimethylene carbonate. One non-aqueous solvent selected from these may be used alone as the non-aqueous solvent. Alternatively, a combination of two or more non-aqueous solvents selected from these may be used as the non-aqueous solvent. The non-aqueous electrolyte solution may contain at least one fluorine solvent selected from the group consisting of fluoroethylene carbonate, methyl fluoropropionate, fluorobenzene, fluoroethyl methyl carbonate, and fluorodimethylene carbonate. Examples of lithium salts that can be used include LiPF6, LiBF4, LiSbF6, LiAsF6, LiSO3CF3, LiN(SO2CF3)2, LiN(SO2C2F5)2, LiN(SO2CF3)(SO2C4F9), and LiC(SO2CF3)3. One lithium salt selected from these can be used alone, or a mixture of two or more lithium salts selected from these can be used.The lithium salt concentration is, for example, in the range of 0.5 mol / liter to 2 mol / liter.

[0097] The gel electrolyte can be a polymer material containing a non-aqueous electrolyte solution. The polymer material may include polyethylene oxide, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, or polymers having ethylene oxide bonds.

[0098] The cations constituting the ionic liquid may include aliphatic quaternary salts such as tetraalkylammonium and tetraalkylphosphonium, aliphatic cyclic ammonium compounds such as pyrrolidiniums, morpholiniums, imidazoliniums, tetrahydropyrimidiniums, piperadiniums, and piperidiniums, and nitrogen-containing heterocyclic aromatic cations such as pyridiniums and imidazoliums. The anions constituting the ionic liquid are PF6. - BF4 - SbF 6- - AsF6 - , SO3CF3 - , N(SO2CF3)2 - , N(SO2C2F5)2 - , N(SO2CF3)(SO2C4F9) - , C(SO2CF3)3 - Other examples are also acceptable. Furthermore, the ionic liquid may contain a lithium salt.

[0099] At least one of the positive electrode layer 520, the electrolyte layer 530, and the negative electrode layer 540 may contain a binder for the purpose of improving the adhesion between particles. The binder is used to improve the bonding properties of the materials constituting the electrode. Examples of binders include polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamideimide, polyacrylonitrile, polyacrylic acid, polymethyl acrylate, polyethyl acrylate, polyhexyl acrylate, polymethacrylic acid, polymethyl methacrylate, polyethyl methacrylate, polyhexyl methacrylate, polyvinyl acetate, polyvinylpyrrolidone, polyether, polyethersulfone, hexafluoropolypropylene, styrene-butadiene rubber, and carboxymethylcellulose. Furthermore, a copolymer of two or more materials selected from tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, vinylidene fluoride, chlorotrifluoroethylene, ethylene, propylene, pentafluoropropylene, fluoromethyl vinyl ether, acrylic acid, and hexadiene may be used as a binder. Alternatively, a mixture of two or more materials selected from these may be used as a binder.

[0100] At least one of the positive electrode layer 520 and the negative electrode layer 540 may contain a conductive additive for the purpose of enhancing electronic conductivity. Examples of conductive additives include graphites such as natural or artificial graphite, carbon blacks such as acetylene black and Ketjenblack, conductive fibers such as carbon fibers or metal fibers, metal powders such as carbon fluoride and aluminum, conductive whiskers such as zinc oxide or potassium titanate, conductive metal oxides such as titanium oxide, and conductive polymer compounds such as polyaniline, polypyrrole, and polythiophene. Using a carbon conductive additive can help reduce costs.

[0101] In another example, the power generation element 5000 may be a stack of multiple power generation elements.

[0102] Multiple power generation elements may be connected to each other, for example, in series. Connecting multiple power generation elements in series can increase the battery voltage. Alternatively, multiple power generation elements may be connected to each other, for example, in parallel. Connecting multiple power generation elements in parallel can increase the battery capacity. The number and method of connection can be appropriately selected depending on the application in which the battery will be used.

[0103] The power generation element 5000 may be a bipolar stack of power generation elements arranged in series. A bipolar stack is one in which the positive electrode layer and the negative electrode layer of an adjacent power generation element are connected by a bipolar current collector that combines the functions of both a positive electrode current collector and a negative electrode current collector in a single unit. By using a bipolar current collector, the volume of the current collector in the battery can be reduced, and the energy density of the battery can be increased.

[0104] The space between the covering 1000 and the lead-out portions of the positive and negative terminals may be sealed with resin or the like. [Industrial applicability]

[0105] The battery relating to this disclosure can be used, for example, as an all-solid-state lithium-ion secondary battery. [Explanation of symbols]

[0106] 100 Base material layer 110 Resin layer 120 metal layer 200 Positive electrode current collector 210 Positive electrode layer 220 Solid electrolyte 230 Negative electrode layer 240 Negative electrode current collector 300 Primer layer 400 resin layer 410 Halogen-free polymers 420 Halogen-containing polymer 510 Positive electrode current collector 520 Positive electrode layer 530 Electrolyte layer 540 Negative electrode layer 550 Negative electrode current collector 1000 Covering 2000 batteries 3000 Covering 4000 Covering 5000 power generation elements

Claims

1. It comprises a power generation unit and a covering body that covers the power generation unit, The aforementioned power generation unit is The positive electrode layer, The negative electrode layer, The system comprises a solid electrolyte layer located between the positive electrode layer and the negative electrode layer, At least one selected from the group consisting of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer includes a solid electrolyte containing a halogen, The aforementioned covering body, A base layer and resin layer, The system comprises a metal layer located between the base material layer and the resin layer, The resin layer is positioned on the side facing the power generation unit and contains a halogen-containing polymer. A battery in which the ionic radius of the halogen contained in the resin layer is the same as or smaller than the ionic radius of the halogen contained in the solid electrolyte.

2. The battery according to claim 1, wherein the metal layer comprises at least one selected from the group consisting of aluminum, aluminum alloy, and stainless steel.

3. The battery according to claim 1, wherein the metal layer includes aluminum.

4. The battery according to claim 1, further comprising a primer layer located between the metal layer and the resin layer.

5. The battery according to claim 4, wherein the primer layer comprises at least one selected from the group consisting of nitrogen, silicon, sulfur, and titanium.

6. The battery according to claim 4, wherein the primer layer comprises at least one selected from the group consisting of a silane coupling agent, a titanate coupling agent, a polyimide, a polyamide, and a polymer having a sulfonic acid group.

7. The battery according to claim 1, wherein the resin layer further comprises a halogen-free polymer.

8. The battery according to claim 1, wherein the halogen-containing polymer is a polymer containing a fluorine atom or a chlorine atom.

9. The halogen-containing polymer is a polymer containing fluorine, The battery according to claim 8, wherein the fluorine-containing polymer comprises at least one selected from the group consisting of tetrafluoroethylene, vinylidene fluoride, perfluoroalkyl vinyl ether, hexafluoropropylene, and chlorotrifluoroethylene.

10. The halogen-containing polymer is a polymer containing fluorine, The battery according to claim 8, wherein the fluorine-containing polymer comprises at least one selected from the group consisting of tetrafluoroethylene, vinylidene fluoride, and hexafluoropropylene.

11. The halogen-containing polymer is a polymer containing fluorine, The battery according to claim 8, wherein the fluorine-containing polymer includes at least one selected from the group consisting of fluorinated polyethylene, fluorinated polypropylene, tetrafluoroethylene-hexafluoropropylene copolymer, polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, polychlorotrifluoroethylene, fluororubber, fluorosilicone rubber, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer, tetrafluoroethylene-propylene rubber, and tetrafluoroethylene-perfluoromethyl vinyl ether rubber.

12. The battery according to claim 1, wherein the halogen concentration in the resin layer increases continuously or stepwise from the metal layer side to the opposite side.

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