battery

Abstract

A battery has a plurality of first electrodes arranged at a prescribed interval, the first electrode having a first current collecting foil and a first electrode layer on a first face of the first current collecting foil, at least one end portion of the four end portions in the face direction of the first electrode layer being positioned at the same position as at least one end portion of the four end portions in the face direction of the first current collecting foil, at least one side face of the four side faces of the first electrode being a flush face, and the plurality of first electrodes being arranged at a prescribed interval on a first face of a second current collecting foil.

Description

Technical Field

[0001] This disclosure relates to batteries. Background Technology

[0002] As with the batteries disclosed in Japanese Patent Application Publication Nos. 2019-192338, 2001-357836, and 2024-176140, various technologies have been proposed for batteries. Summary of the Invention

[0003] Japanese Patent Application Publication No. 2019-192338 discloses an all-solid-state battery that suppresses capacity reduction by forming slit-like grooves on the electrodes. When grooves (uncoated portions where no electrode binder is applied) are formed on the electrodes, it is difficult to avoid electrode binder collapse at the edges of the coated portions, thus contributing to a decrease in electrode capacitance. Therefore, electrodes with more grooves have a larger area of ​​capacity loss compared to electrodes with fewer grooves or no grooves.

[0004] This disclosure was made in view of the above-mentioned circumstances, and its main objective is to provide a battery capable of suppressing the capacity reduction of the electrodes.

[0005] That is, the present invention includes the following aspects.

[0006] [1]. A battery having multiple first electrodes,

[0007] The first electrode has a first current collector foil and a first electrode layer on a first surface of the first current collector foil.

[0008] The position of at least one of the four ends of the first electrode layer in the planar direction is the same as the position of at least one of the four ends of the first current collector foil in the planar direction.

[0009] At least one of the four sides of the first electrode is a flush plane.

[0010] The plurality of the first electrodes are arranged at predetermined intervals on the first surface of a second collector foil.

[0011] [2]. As described in [1], the first current collector foil contains: resin and conductive inorganic filler,

[0012] The resin is a thermosetting resin.

[0013] [3]. As described in [1], each of the first current collector foils of the plurality of first electrodes is bonded to the second current collector foil via an adhesive layer.

[0014] The adhesive layer contains: an adhesive and a conductive inorganic filler.

[0015] The adhesive is a heat-melting resin.

[0016] [4]. [1] The method for manufacturing the battery includes a step of forming the first electrode layer by dry film deposition on the first surface of the first current collector foil.

[0017] [5]. The battery manufacturing method as described in [4] further comprises, after the forming process:

[0018] The process of preparing multiple of the first electrodes, and

[0019] The process of arranging a plurality of the first electrodes on the first surface of a second collector foil at predetermined intervals.

[0020] According to the present invention, a battery capable of suppressing the decrease in electrode capacitance can be provided. Attached Figure Description

[0021] Figure 1 This is a schematic diagram illustrating one example of a bipolar battery according to the present disclosure;

[0022] Figure 2 This is a schematic diagram illustrating another example of a bipolar battery according to the present disclosure;

[0023] Figure 3 This is a schematic diagram illustrating an example of a unipolar battery according to the present disclosure;

[0024] Figure 4 This is a schematic diagram illustrating a portion of a conventional bipolar battery. Detailed Implementation

[0025] The features, advantages, and technical and industrial significance of this disclosure will now be described with reference to the accompanying drawings, wherein the same symbols denote the same components.

[0026] In this disclosure, a battery is provided.

[0027] The battery has multiple first electrodes.

[0028] The first electrode has a first current collector foil and a first electrode layer on a first surface of the first current collector foil.

[0029] The position of at least one of the four ends of the first electrode layer in the planar direction is the same as the position of at least one of the four ends of the first current collector foil in the planar direction.

[0030] At least one of the four sides of the first electrode is a flush plane.

[0031] The plurality of the first electrodes are arranged at predetermined intervals on the first surface of a second collector foil.

[0032] According to this disclosure, by fabricating multiple first electrodes comprising a first electrode layer pre-coated on a first current collector foil, and bonding the multiple first electrodes to a second current collector foil in an island-like manner, an electrode is formed in which the edge of the first electrode layer has no electrode adhesive collapse. According to this disclosure, electrode adhesive collapse can be eliminated, and the decrease in electrode capacitance can be suppressed.

[0033] Electrode 1

[0034] The battery disclosed herein has a plurality of first electrodes.

[0035] The first electrode has a first current collector foil and a first electrode layer on the first surface of the first current collector foil.

[0036] The first electrode can be either positive or negative. When the first electrode is positive, the first electrode layer is a positive electrode layer. When the first electrode is negative, the first electrode layer is a negative electrode layer.

[0037] The first electrode, the first current collector foil, and the first electrode layer can be quadrilaterals when viewed from above, and in particular, they can be rectangular. The first electrode, the first current collector foil, and the first electrode layer can also be quadrangular prisms.

[0038] The position of at least one of the four ends of the first electrode layer in the planar direction is the same as the position of at least one of the four ends of the first current collector foil in the planar direction. That is, the first electrode layer end on at least one side of the first electrode and the first current collector foil end on at least one side share the same end position. The positions of the four ends of the first electrode layer in the planar direction can be the same as the positions of the four ends of the first current collector foil in the planar direction.

[0039] At least one of the four sides of the first electrode is a flush plane.

[0040] Multiple first electrodes are arranged at predetermined intervals on the first surface of a second collector foil. The predetermined interval is not particularly limited, but can be appropriately set to reduce electrode capacitance loss.

[0041] The number of first electrodes can be, for example, 2 to 100.

[0042] The first electrode layer can be a single-layer structure or a two-layer structure.

[0043] The first electrode layer contains at least an electrode active material, and may also contain conductive materials, binders, etc., as described later, if needed. The electrode active material is either the positive electrode active material or the negative electrode active material, as described later.

[0044] The battery disclosed herein may also have an electrolyte layer on the surface of the first electrode layer opposite to the surface of the first current collector foil.

[0045] The battery disclosed herein has a second collector foil.

[0046] The battery disclosed herein may have a second current collector foil on a second surface opposite to the first surface of the first current collector foil.

[0047] The first collector foil can be bonded to the second collector foil. The first collector foil can also be electrically bonded to the second collector foil.

[0048] In this disclosure, when the first electrode is a positive electrode, the first collector foil and the second collector foil are the first positive collector foil and the second positive collector foil, respectively; when the first electrode is a negative electrode, the first collector foil and the second collector foil are the first negative collector foil and the second negative collector foil, respectively.

[0049] At least one of the plurality of ends of the first current collector foil facing the outer side of the battery in the planar direction may also have a protrusion extending toward the outer side of the battery without being opposite to the first electrode layer.

[0050] The first collector foil can also be made of metallic materials. Examples of metallic materials that can be used for the first collector foil include SUS, Cr, Au, Pt, Zn, Al, copper, nickel, iron, and titanium.

[0051] The second collector foil can also be made of metallic materials. Materials that are the same as those used for the first collector foil can be listed as suitable metallic materials for the second collector foil.

[0052] The thickness of the first and second collector foils can, for example, be 1 to 30 μm.

[0053] The first collector foil can also be made of resin.

[0054] The first collector foil can contain resin and conductive inorganic fillers.

[0055] The resin can be a heat-melting resin, modified siloxane, epoxy resin, etc. The heat-melting resin can be a modified polyolefin. Modified polyolefins can be maleic acid-modified polypropylene, acid-modified polyethylene, etc.

[0056] The conductive filler can be carbon, Ni, Co, etc.

[0057] From the perspective of suppressing corrosion caused by electrolyte, the first current collector foil can also be a three-layer structure consisting of an Al layer, a resin layer containing polyethylene terephthalate and inorganic fillers, and an Al layer in sequence.

[0058] The first current collector foil can also be bonded to the second current collector foil via an adhesive layer. When the first current collector foil is made of resin, it also functions as an adhesive layer, so an adhesive layer is not necessarily required. When the first current collector foil is made of a metallic material, an adhesive layer can be provided from the viewpoint of fixing it to the second current collector foil.

[0059] An adhesive layer is simply a layer that can be fused together and bonded to dissimilar materials such as metals. An adhesive layer can contain adhesives and conductive inorganic fillers.

[0060] The adhesive can be a resin. Examples of resins that are the same as those used in the first current collector foil can be listed. Examples of inorganic fillers that are the same as those used in the first current collector foil can be listed.

[0061] The thickness of the adhesive layer can be, for example, 0.1~4μm.

[0062] The battery disclosed herein has a second current collector foil, a plurality of first electrodes, and typically also has an electrolyte layer and a second electrode.

[0063] The electrolyte layer can also be disposed on the surface opposite to the surface of the first electrode that is in contact with the second current collector foil.

[0064] Second electrode

[0065] The second electrode can be disposed on the second surface of the second current collector foil opposite to the first surface on which the plurality of first electrodes are disposed, or it can be disposed on the surface of the electrolyte layer opposite to the surface in contact with the plurality of first electrodes.

[0066] The second electrode is the negative electrode when the first electrode is the positive electrode, and the positive electrode when the first electrode is the negative electrode.

[0067] The second electrode may also have a second electrode layer and a third current collector foil.

[0068] The second electrode layer and the third current collector foil are the positive electrode layer and the positive current collector foil, respectively, when the second electrode is the positive electrode, and the negative electrode layer and the negative current collector foil, respectively, when the second electrode is the negative electrode.

[0069] positive electrode

[0070] The positive electrode has a positive electrode layer and a positive electrode current collector foil.

[0071] The positive electrode layer can be disposed on one side or both sides of the positive electrode current collector foil. The positive electrode can also form a multilayer structure by forming two or more positive electrode layers on at least one side of the positive electrode current collector foil. Furthermore, when two or more positive electrode layers are formed, the types of positive electrode active materials contained in each positive electrode layer can be the same or different.

[0072] The positive electrode layer is a layer containing at least a positive electrode active material. Additionally, depending on the requirements, the positive electrode layer may also contain at least one of a solid electrolyte, a conductive material, and a binder.

[0073] Examples of positive electrode active materials include oxide active materials. Examples of oxide active materials include LiCoO2, LiMnO2, LiNiO2, LiVO2, and LiNi. 1 / 3 Co 1 / 3 Mn 1 / 3 O2 and LiNi 0.8 Mn 0.1 Co 0.1 O2 and other layered rock salt active substances. Additionally, as oxide active substances, examples include LiMn2O4 and Li4Ti5O. 12 and Li(Ni) 0.5 Mn 1.5 Spinel-type active materials such as O4. In addition, olivine-type active materials such as LiFePO4, LiMnPO4, LiNiPO4, and LiCoPO4 can be listed as oxide active materials.

[0074] A coating containing a Li-ion-conducting compound can also be formed on the surface of the positive electrode active material. This is because it can suppress the reaction between the positive electrode active material and the solid electrolyte (especially a sulfide solid electrolyte). Examples of Li-ion-conducting compounds include B₂O₃, Li₂B₄O₇, LiBPO₄, Li₃PO₄, LiPO₃, and LiNbO₃. The coating thickness is, for example, 1 nm to 30 nm. The coverage rate of the Li-ion-conducting compound on the positive electrode active material is, for example, 70% or more, 90% or more, or 100%. There are no particular limitations on the coating method of the Li-ion-conducting compound; conventionally known methods can be appropriately used.

[0075] The positive electrode active material is usually in the form of particles. The positive electrode active material can be primary particles or secondary particles formed by the aggregation of primary particles.

[0076] There is no particular limitation on the average particle size of the positive electrode active material. For example, it can be above 0.01 μm and below 50 μm, or it can be above 0.5 μm and below 30 μm.

[0077] In this disclosure, an example of a method for calculating the average particle size is as follows. First, for a given particle, the particle size is calculated by considering the particle as spherical in a transmission electron microscope (TEM) image or scanning electron microscope (SEM) image at an appropriate magnification (e.g., 50,000 to 1,000,000 times). The particle size is calculated for 2 to 300 particles of the same type through such TEM or SEM observations, and the average value of these particles is taken as the average particle size.

[0078] The proportion of positive electrode active material in the positive electrode layer can be, for example, 20% by mass or more, 30% by mass or more, or 40% by mass or more. If the proportion of positive electrode active material is too low, sufficient energy density may not be obtained. On the other hand, the proportion of positive electrode active material in the positive electrode layer can be, for example, 95% by mass or less, 70% by mass or less, or 60% by mass or less. If the proportion of positive electrode active material is too high, the ionic conductivity and electronic conductivity of the positive electrode layer may be relatively reduced.

[0079] The positive electrode layer can also contain a solid electrolyte. Adding a solid electrolyte improves the ionic conductivity of the positive electrode layer. The solid electrolyte can be an inorganic solid electrolyte such as a sulfide solid electrolyte, a halide solid electrolyte, an oxide solid electrolyte, or a complex hydride solid electrolyte, or an organic solid electrolyte such as a gel electrolyte.

[0080] From an operational point of view, solid electrolytes can be in the form of particles.

[0081] In addition, there is no particular limitation on the average particle size of the solid electrolyte particles; it can range from 1 nm to 100 μm.

[0082] The proportion of solid electrolyte in the positive electrode layer can be, for example, 1% by mass or more. If the proportion of solid electrolyte is too low, the ion conduction pathways in the positive electrode layer may be insufficient. On the other hand, the proportion of solid electrolyte in the positive electrode layer can be, for example, 60% by mass or less. When the proportion of solid electrolyte is too high, the proportion of positive electrode active material becomes relatively low, and the energy density may become lower.

[0083] The positive electrode layer can also contain conductive materials. Adding conductive materials improves the electronic conductivity of the positive electrode layer. Examples of conductive materials include carbon-based conductive materials, metal particles, and conductive polymers. Examples of carbon-based conductive materials include particulate materials such as acetylene black (AB) and Ketjen black (KB). Other examples of carbon-based conductive materials include fibrous materials such as fumed carbon fiber (VGCF), carbon nanotubes (CNTs), and carbon nanofibers (CNFs).

[0084] The proportion of conductive material in the positive electrode layer can be, for example, 0.1% by mass or more. If the proportion of conductive material is too low, the electron conduction pathway in the positive electrode layer may be insufficient. On the other hand, the proportion of conductive material in the positive electrode layer can be, for example, 5% by mass or less. If the proportion of conductive material is too high, the proportion of positive electrode active material becomes relatively low, and there is a possibility of a decrease in energy density.

[0085] The positive electrode layer may also contain an adhesive. Examples of adhesives include styrene-butadiene rubber (SBR), polyimide (PI), polyacrylic acid (PAA), acrylonitrile-butadiene rubber (NBR), butadiene rubber (BR), polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTFE), styrene-isoprene-styrene block copolymer (SIS), and ethylene-propylene-diene copolymer (EPDM).

[0086] The proportion of binder in the positive electrode layer can be, for example, 0.5% by mass or more. If the proportion of binder is too low, it may not be sufficient to reduce the increase in resistance caused by charging and discharging. On the other hand, the proportion of binder in the positive electrode layer can be, for example, 15% by mass or less. When the proportion of binder is too high, the proportion of positive electrode active material becomes relatively low, and the energy density may become lower.

[0087] The thickness of the positive electrode layer can be, for example, 0.1 μm or more and 1000 μm or less, or 1 μm or more and 500 μm or less, or 30 μm or more and 100 μm or less.

[0088] There is no particular limitation on the manufacturing method of the positive electrode layer. For example, a method can be described as mixing the above-mentioned positive electrode active material, the above-mentioned solid electrolyte, and a solvent to obtain a positive electrode slurry, coating the positive electrode slurry onto a positive electrode current collector foil, and drying it to form a positive electrode layer. During the formation of the positive electrode layer, a pressing process can also be performed on the positive electrode layer in the thickness direction. Examples of pressing processes include roll pressing and flat pressing.

[0089] Examples of solvents include, for example, N-methylpyrrolidone (NMP), tetrahydronaphthalene, diisobutyl ketone, butyl butyrate, mesitylene, heptane, dibutyl ether, decane, dodecane, isodecanene, and toluene. A solvent may contain two or more of these components.

[0090] negative electrode

[0091] The negative electrode has a negative electrode layer and a negative electrode current collector foil.

[0092] The negative electrode layer can be disposed on one side or both sides of the negative electrode current collector foil. The negative electrode can also form a multilayer structure by forming two or more negative electrode layers on at least one side of the negative electrode current collector foil. Furthermore, when forming two or more negative electrode layers, the types of negative electrode active materials contained in each negative electrode layer can be the same or different.

[0093] The negative electrode layer is a layer containing at least a negative electrode active material. Additionally, depending on the requirements, the negative electrode layer may also contain at least one of a solid electrolyte, a conductive material, and a binder.

[0094] The negative electrode active material may contain at least one selected from carbon-based active materials, Li-based active materials, Si-based active materials, Si-C composite materials, and lithium titanate. Carbon-based active materials may contain at least one selected from graphite, soft carbon, and hard carbon. Li-based active materials may include, for example, Li, Li silicates, and Li alloys. Si-based active materials may include, for example, Si, SiO, and Si alloys. Si-C composite materials refer to composite materials of carbon-based active materials (such as graphite) and Si-based active materials (such as Si).

[0095] The negative electrode layer may contain more than 10% by mass of negative electrode active material, more than 20% by mass, more than 50% by mass, less than 100% by mass, or less than 90% by mass.

[0096] Regarding the solid electrolyte, conductive material, and binder used in the negative electrode layer, the same solid electrolyte, conductive material, and binder described in the positive electrode layer above can be listed.

[0097] The proportion of solid electrolyte in the negative electrode layer can be, for example, more than 0% by mass or less than 60% by mass.

[0098] The proportion of conductive material in the negative electrode layer can be, for example, more than 0.1% by mass and less than 5% by mass.

[0099] The proportion of binder in the negative electrode layer can be, for example, more than 0.5% by mass and less than 15% by mass.

[0100] Electrolyte layer

[0101] The electrolyte layer is a layer formed between the positive electrode layer and the negative electrode layer, and it contains at least one electrolyte. The electrolyte can be a solid electrolyte or a liquid electrolyte (electrolyte).

[0102] The electrolyte layer may contain solid electrolytes and electrolyte solutions.

[0103] Regarding solid electrolytes, the same solid electrolytes described in the above positive electrode layer can be listed.

[0104] Electrolytes can be aqueous or non-aqueous. They can be used alone or in combination of two or more.

[0105] Aqueous electrolytes contain water as a major solvent component. Specifically, based on the total amount of solvent (liquid component) constituting the electrolyte (100 mol%), water can account for 50 mol% or more, particularly 70 mol% or more, and further, 90 mol% or more. On the other hand, there is no particular upper limit on the proportion of water in the solvent.

[0106] The solvent contains water as its main component, but may also contain solvents other than water. Examples of solvents other than water include one or more selected from ethers, carbonates, nitriles, alcohols, ketones, amines, amides, sulfur compounds, and hydrocarbons. The amount of solvents other than water, based on the total amount (100 mol%) of the solvent (liquid component) constituting the electrolyte, may be 50 mol% or less, particularly 30 mol% or less, and possibly 10 mol% or less.

[0107] The aqueous electrolyte used in this disclosure comprises an electrolyte. Electrolytes used in aqueous electrolytes can be conventionally known electrolytes. Examples of electrolytes include lithium salts, nitrates, acetates, and sulfates of imide compounds. Specific examples of electrolytes include lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium bis(pentafluoroethanesulfonyl)imide (LiBETI), lithium bis(nonafluorobutyryl)imide, lithium nonafluoro-N-[trifluoromethanesulfonyl]butyrylamide, lithium N,N-hexafluoro-1,3-disulfonylimide, CH3COOLi, LiPF6, LiBF4, Li2SO4, and LiNO3.

[0108] Regarding the concentration of the electrolyte in the aqueous electrolyte, it can be appropriately set according to the required battery characteristics, provided it does not exceed the saturation concentration of the electrolyte relative to the solvent. This is because if solid electrolyte residue remains in the aqueous electrolyte, the solid may hinder the battery reaction.

[0109] For example, when using LiTFSI as the electrolyte, the aqueous electrolyte may contain more than 1 mol of LiTFSI per 1 kg of the aforementioned water, particularly more than 5 mol, and even more than 7.5 mol. There is no particular upper limit; for example, it may also be less than 25 mol.

[0110] As a non-aqueous electrolyte, an electrolyte containing lithium salt and non-aqueous solvent is usually used.

[0111] Examples of lithium salts include inorganic lithium salts such as LiPF6, LiBF4, LiClO4, and LiAsF6; and organic lithium salts such as LiCF3SO3, LiN(SO2CF3)2(Li-TFSI), LiN(SO2C2F5)2, and LiC(SO2CF3)3.

[0112] Examples of non-aqueous solvents include ethylene carbonate (EC), propylene carbonate (PC), butyl carbonate (BC), dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (EMC), γ-butyrolactone, sulfolane, acetonitrile (AcN), dimethoxymethane, 1,2-dimethoxyethane (DME), 1,3-dimethoxypropane, diethyl ether, tetraethylene glycol dimethyl ether (TEGDME), tetrahydrofuran, 2-methyltetrahydrofuran, dimethyl sulfoxide (DMSO), and mixtures thereof. From the viewpoint of ensuring high dielectric constant and low viscosity, a non-aqueous solvent could be a mixture of cyclic carbonate compounds such as EC, PC, and BC, which have high dielectric constant and high viscosity, and chain carbonate compounds such as DMC, DEC, and EMC, which have low dielectric constant and low viscosity. A mixture of EC and DEC could also be a non-aqueous solvent.

[0113] The concentration of lithium salt in non-aqueous electrolytes can be, for example, 0.3–5 M.

[0114] In the electrolyte layer, a membrane impregnated with the above-mentioned electrolyte can also be used to prevent the positive electrode layer from contacting the negative electrode layer.

[0115] There are no particular limitations on the material used for the membrane, as long as it is a porous membrane. Examples include polyethylene (PE), polypropylene (PP), polyester, polyvinyl alcohol, cellulose, and polyamide resins. Among these, polyethylene and polypropylene can be used as membrane materials. Furthermore, the aforementioned membranes can be single-layer or multi-layer structures. Examples of multi-layer membranes include double-layer PE / PP membranes, or triple-layer PP / PE / PP or PE / PP / PE membranes.

[0116] The diaphragm can also be made of resin nonwoven fabric, glass fiber nonwoven fabric, or other nonwoven fabrics.

[0117] solid electrolyte layer

[0118] The electrolyte layer can also be a solid electrolyte layer composed of solids.

[0119] When the electrolyte layer is a solid electrolyte layer, the solid electrolyte layer contains solid electrolyte and, if necessary, adhesives, etc.

[0120] Solid electrolytes can be listed as the same solid electrolytes described in the above positive electrode layer.

[0121] Solid electrolytes can be used alone or in combination with two or more types. Furthermore, when using two or more solid electrolytes, they can be mixed, or they can form two or more layers of solid electrolyte to create a multilayer structure.

[0122] The proportion of solid electrolyte in the solid electrolyte layer is not particularly limited; for example, it can be in the range of 50% or more by mass, 60% or more by mass but less than 100% by mass, 70% or more by mass but less than 100% by mass, or 100% by mass. The solid electrolyte layer may contain less than 1% by mass of electrolyte relative to the total amount of solid electrolyte layer.

[0123] Examples of adhesives that can be included in the above-mentioned positive electrode layer include adhesives.

[0124] The content of binder in the solid electrolyte layer can be 0% to 10% by mass relative to the total amount of the solid electrolyte layer.

[0125] The thickness of the electrolyte layer can be, for example, 0.1 μm or more and 1000 μm or less, or 0.1 μm or more and 500 μm or less, or 0.1 μm or more and 100 μm or less.

[0126] The battery disclosed herein may also include a constraint clamp that applies constraint pressure to the positive electrode layer, electrolyte layer, and negative electrode layer along the thickness direction. In particular, when the electrolyte layer is a solid electrolyte layer, constraint pressure can be applied to form good ion conduction pathways and electron conduction pathways. The constraint pressure may be, for example, 0.1 MPa or more, 1 MPa or more, or 5 MPa or more. On the other hand, the constraint pressure may be, for example, 100 MPa or less, 50 MPa or less, or 20 MPa or less.

[0127] Battery

[0128] There is no particular limitation on the type of battery disclosed herein, but lithium-ion batteries are typical. Furthermore, the battery disclosed herein can be a liquid battery with an electrolyte layer containing an electrolyte solution, or a solid battery with an electrolyte layer containing a solid electrolyte. Solid batteries can be semi-solid batteries or all-solid batteries. In this disclosure, a semi-solid battery is a battery whose electrolyte layer contains both solid components such as inorganic solid electrolytes and liquid components (e.g., solvents and electrolyte solutions). In this disclosure, an all-solid battery is a battery whose electrolyte layer contains only solid components such as inorganic solid electrolytes. Additionally, the battery disclosed herein can be a primary battery or a secondary battery, especially a secondary battery. This is because it can be repeatedly charged and discharged, making it useful, for example, as a vehicle battery.

[0129] In the case of a battery pack with multiple batteries stacked together, the battery pack can be either unipolar or bipolar.

[0130] Batteries are used in various applications, including as a power source for vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), gasoline vehicles, and diesel vehicles. Specifically, they can be used as a power source for driving HEVs, PHEVs, or BEVs. Furthermore, batteries can be used as a power source for mobile bodies other than vehicles (such as railways, ships, and aircraft), and also for electrical products such as information processing devices.

[0131] Battery manufacturing method

[0132] This disclosure provides a method for manufacturing a battery, which includes a step of forming a first electrode layer by dry film deposition on a first surface of a first current collector foil.

[0133] The battery manufacturing method includes a step of forming the first electrode layer on the first surface of the first current collector foil by dry film deposition (forming step). The battery manufacturing method may also include a step of preparing a plurality of the first electrodes after the forming step (preparation step); and a step of arranging the plurality of the first electrodes on the first surface of a second current collector foil at predetermined intervals (arranging step).

[0134] In the formation process, the first electrode layer is formed by dry film deposition, thus eliminating the need for solvents and reducing manufacturing costs. The formation process yields a laminate in which the first electrode layer is formed on the first surface of the first current collector foil.

[0135] In the preparation process, multiple of the above-mentioned laminates are obtained by repeating the forming process. For each laminate, the ends can also be cut off with at least one of the four sides of each laminate being flush with the same end position, i.e., multiple first electrodes are obtained.

[0136] In the configuration step, a plurality of first electrodes prepared in the preparation step are configured on the first surface of a second collector foil. The specified intervals when the plurality of first electrodes are configured on the first surface of the second collector foil are as described above.

[0137] Figure 1 This is a schematic diagram illustrating an example of a bipolar battery according to the present disclosure.

[0138] like Figure 1 As shown, the bipolar battery 100 of this disclosure has a plurality of first electrodes 10 having a first electrode layer 12 on the first surface of the first current collector foil 11. Figure 1 As shown, at least two ends of the first electrode layer and at least two ends of the first current collector foil share the same end positions, that is, at least two sides of the first electrode 10 are flush with the plane. This eliminates electrode adhesion collapse at the ends of at least two sides of the first electrode layer 12. The second current collector foil 13 is bonded to the second surface of the first current collector foil 11 opposite to the first surface via an adhesive layer 20. The battery 100 has a second electrode 30 with a second electrode layer 32 on the first surface of the third current collector foil 31. The third current collector foil 31 is bonded to the second current collector foil 13 on the second surface opposite to the first surface to which the first current collector foil 11 is bonded via an adhesive layer 21.

[0139] Figure 2 This is a schematic diagram illustrating another example of a bipolar battery as described in this disclosure. Figure 2 In the middle, to and Figure 1 The same structure is assigned the same number, and its description is omitted.

[0140] like Figure 2 As shown, the bipolar battery 200 of this disclosure has at least one first electrode layer end and at least one first current collector foil end sharing the same end position, that is, at least one side of the first electrode 10 is flush with the plane. This eliminates electrode slump at the end of at least one side of the first electrode layer 12. Furthermore, at least one end of the first current collector foil 11 facing the outer side of the battery 200 in the planar direction has a protrusion 14 extending towards the outer side of the battery 200 without opposing the first electrode layer 12.

[0141] Figure 3 This is a schematic diagram illustrating an example of a unipolar battery according to the present disclosure. Figure 3In the middle, to and Figure 1 The same structure is assigned the same number, and its description is omitted. Figure 3 The "…" in the text indicates a repeated structure.

[0142] like Figure 3 As shown, the unipolar battery 300 of this disclosure has a plurality of first electrodes 10 having a first electrode layer 12 on the first surface of the first current collector foil 11. A second current collector foil 13 is bonded to the second surface of the first current collector foil 11 on the side opposite to the first surface via an adhesive layer 20. On the second current collector foil 13, the first current collector foil 11 is also bonded to the second surface of the second current collector foil 13 on the side opposite to the first surface to which the first current collector foil 11 is bonded via an adhesive layer 20. The battery 300 also has a plurality of first electrodes 10 having a first electrode layer 12 on the second surface of the second current collector foil 13, which is also on the first surface of the first current collector foil 11. Figure 3 As shown, at least two ends of the first electrode layer and at least two ends of the first current collector foil share the same end positions, that is, at least two sides of the first electrode 10 are flush with each other. This eliminates electrode overlap at the ends of at least two sides of the first electrode layer 12. The battery 300 has a second electrode 30 with a second electrode layer 32 on the first surface of the third current collector foil 31, and also has a second electrode 30 with a second electrode layer 32 on the second surface of the third current collector foil 31. A separator 50, serving as an electrolyte layer, is disposed between the first electrode layer 12 and the second electrode layer 32. Figure 3 The first electrode 10 shown is the positive electrode, and the second electrode 30 is the negative electrode.

[0143] Figure 4 This is a schematic diagram illustrating a portion of a conventional bipolar battery. Figure 4 In the middle, to and Figure 1 The same structure is assigned the same number, and its description is omitted.

[0144] like Figure 4 As shown, a conventional bipolar battery 500 has multiple first electrodes 10 with first electrode layers 12 on the first surface of the second current collector foil 13. The first electrode layer 12 is formed by directly coating the electrode composite material of the first electrode layer onto the first surface of the second current collector foil 13, thus forming an electrode composite collapse edge 40 at the end of the first electrode layer 12 in the planar direction. Considering the electrode composite collapse edge 40, the electrode area is reduced, and the battery capacity is reduced. In particular, when the first electrode layer 12 has a two-layer structure, when coating the electrode composite material of the first electrode layer 12 with two layers, in addition to the electrode composite collapse edge 40, the coating deviation of the electrode composite material also needs to be considered, which further reduces the electrode area and the battery capacity.

[0145] Furthermore, this disclosure is not limited to the embodiments described above. The embodiments described above are merely illustrative, and any embodiment that has the same technical concept and substantially the same structure as described in the claims of this disclosure and achieves the same effect is included within the technical scope of this disclosure.

Claims

1. A battery having a plurality of first electrodes, The first electrode has a first current collector foil and a first electrode layer on a first surface of the first current collector foil. The position of at least one of the four ends of the first electrode layer in the planar direction is the same as the position of at least one of the four ends of the first current collector foil in the planar direction. At least one of the four sides of the first electrode is a flush plane. The plurality of the first electrodes are arranged at predetermined intervals on the first surface of a second collector foil.

2. The battery as claimed in claim 1, wherein the first current collector foil comprises: resin and conductive inorganic filler, The resin is a thermosetting resin.

3. The battery as claimed in claim 1, wherein each of the plurality of first electrodes, a first current collector foil, is bonded to the second current collector foil via an adhesive layer. The adhesive layer contains: an adhesive and a conductive inorganic filler. The adhesive is a heat-melting resin.

4. The method for manufacturing the battery according to claim 1, comprising a step of forming the first electrode layer by dry film deposition on the first surface of the first current collector foil.

5. The method for manufacturing a battery as described in claim 4, further comprising, after the forming step: The process of preparing multiple of the first electrodes, and The process of arranging a plurality of the first electrodes on the first surface of a second collector foil at predetermined intervals.

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