Ion-conducting membranes, electrode complexes, and batteries

Abstract

The present invention provides a secondary battery in which the mixing of electrolytes of different compositions is suppressed for a long period of time. [Solution] An electrode composite comprising an ion-conducting membrane and an electrode, wherein the porosity of the ion-conducting membrane is 0% or more and 10% or less, and the electrode is enclosed by the ion-conducting membrane.

Description

Technical Field

[0001] The present invention relates to an ion conductive membrane, an electrode composite, and a battery.

Background Art

[0002] In recent years, portable electronic devices have been becoming smaller and more highly functional. Along with this, there is a demand for higher energy density of the battery as its power source. For higher energy density, various battery configurations and materials have been studied.

[0003] From such a background, heretofore, a battery having different compositions on the positive electrode side and the negative electrode side, a solid electrolyte or an ion conductive membrane for separating two types of electrolytic solutions thereof have been proposed. In Patent Document 1, a lithium air battery using a solid electrolyte having a NASICON-type crystal structure as a separation layer is disclosed. In Patent Document 2, a non-aqueous electrolyte secondary battery using a polymer membrane having different compositions of electrolytic solutions on the negative electrode side and the positive electrode side, a gas permeability greater than 10000 seconds, and an ion conductivity of 1×10 -5 S / cm or more is disclosed. In Patent Document 3, a polymer ion conductive membrane having both ion conductivity and liquid separation property is disclosed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] When the electrolytes for the positive and negative electrodes have different compositions, it is necessary to isolate the two electrolytes within the battery. If the isolation between the two electrolytes is insufficient, the two electrolytes will mix, resulting in a decrease in battery capacity and cycle life.

[0006] To address these challenges, Patent Documents 1 and 2 use solid electrolytes or polymer membranes with liquid-separating properties as separators. However, to completely isolate the two types of electrolytes, the separator is held in place from both sides by a resin or metal housing. As a result, these housings occupy a large proportion of the battery's weight and volume, leading to a low energy density. Patent Document 3 does not describe a method for isolating the two types of electrolytes within the battery. [Means for solving the problem]

[0007] To solve the above problems, the present invention encompasses the following (1) to (17). (1) An electrode composite having an ion-conducting membrane and an electrode, wherein the porosity of the ion-conducting membrane is 0% or more and 10% or less, and the electrode is enclosed by the ion-conducting membrane. (2) The electrode composite according to (1), wherein the bending radius of the ion conductive film is 0 mm or more and 10 mm or less. (3) The electrode composite according to (1) or (2), having an electrolyte between the electrode and the ion-conducting membrane. (4) The electrode composite according to (1), wherein the electrode is sealed with the ion conductive film alone, or with the ion conductive film and an adhesive material alone. (5) The electrode composite according to any one of (1) to (4), wherein the electrode is metallic Li. (6) The permeation rate of the 1M LiPF6PC (lithium propylene carbonate hexafluoride phosphate) electrolyte through the ion-conducting membrane is 0 mg / cm². 2 / day or more 0.1mg / cm 2 An electrode complex described in any of (1) to (5) below / day. (7) The electrode composite according to any of (1) to (6), wherein the maximum free volume radius of the ion-conducting membrane is 0.15 nm or more and 0.38 nm or less. (8) An electrode composite according to any of (1) to (7) having an inorganic solid electrolyte layer. (9) A battery comprising any electrode composite described in (1) to (8) and a counter electrode of the electrode of the electrode composite. (10) The battery according to (9), wherein the electrode composite and the counter electrode are sealed in a bag-like manner with an outer material. (11) A battery according to (9) or (10) having an electrolyte. (12) The battery according to (11), having two or more electrolytes, each with a different composition. (13) The battery according to (12), wherein the electrode composite has an electrolyte (electrolyte A) between the ion conductive membrane and the electrode, and has an electrolyte (electrolyte B) with a different composition from electrolyte A between the electrode composite and the counter electrode. (14)(9) Vehicles, unmanned transport vehicles, flying objects, electronic equipment or stationary power sources containing batteries as described above. (15) The porosity is 0% or more and 10% or less, and the permeation rate of 1M LiPF6PC (lithium propylene carbonate hexafluoride phosphate) electrolyte is 0 mg / cm². 2 / day or more 0.1mg / cm 2 Ion-conducting membrane with a capacity of less than / day. (16) The ion-conducting membrane according to (15), wherein the maximum free volume radius of the ion-conducting membrane is 0.15 nm or more and 0.38 nm or less. (17) The ion-conducting membrane according to (15), having an inorganic solid electrolyte layer. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a battery (hereinafter referred to as a two-liquid battery) composed of electrolytes of different compositions in which the mixing of these electrolytes is suppressed for a long period of time. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram representing an ion-conducting film that has undergone plasma treatment. [Figure 2] This is a schematic diagram representing one aspect of the present invention (Example 1). [Figure 3]This is a schematic diagram representing one aspect of the present invention (Example 6). [Modes for carrying out the invention]

[0010] The present invention will be described in detail below.

[0011] One aspect of the present invention is an electrode composite enclosed with an ion-conducting film. Another aspect of the present invention is a battery containing the electrode composite or an ion-conducting film that can be used in the electrode composite.

[0012] One embodiment of the electrode composite of the present invention is an electrode composite having an ion-conducting film and an electrode, wherein the porosity of the ion-conducting film is 0% or more and 10% or less, and the electrode is enclosed with the ion-conducting film. By enclosing the electrode with an ion-conducting film having a porosity within the above range, it is possible to suppress the mixing of each electrolyte in the two-liquid battery when used as an electrode composite of a two-liquid battery. The porosity is preferably 0% or more and 5% or less, more preferably 0% or more and 3% or less, and particularly preferably 0% or more and 1% or less. There is no particular limit to the method for achieving the porosity of the ion-conducting film within this range, but one example is the use of a polymer film as described later. Here, "the electrode is enclosed with an ion-conducting film" means that 50% or more of the surface area of ​​the electrode is covered with the ion-conducting film. In order to suppress the mixing of each electrolyte in the two-liquid battery, the ratio of the electrode's surface area covered with the ion-conducting film is preferably 90% or more and 100%, more preferably 95% or more and 100%, even more preferably 99% or more and 100%, and particularly preferably 100%. The method for determining the ratio of the ion-conducting film covering the electrode surface area is not particularly limited, but one method is to seal it in a bag-like manner with the ion-conducting film described later. Here, the ion-conducting film has an ionic conductivity of 1.0 × 10⁻⁶. -7 This refers to a solid film with an ionic conductivity of S / cm or higher. There is no particular upper limit to the ionic conductivity of an ion-conducting film, but the ionic conductivity is 1.0 × 10⁻⁶. -6 A ratio of S / cm or more, preferably 10 S / cm, is preferred. -5More preferably, it is 10 S / cm or more and less than 100 S / cm, and 2.0×10 -5 More preferably, it is 10 S / cm or more and less than 100 S / cm, and 1.0×10 -4 More preferably, it is 10 S / cm or more and less than 100 S / cm, and 1.0×10 -3 More preferably, it is 10 S / cm or more and less than 100 S / cm. By being within the above range, the resistance of the battery is reduced, and the energy density and lifespan are improved. The method for setting the ionic conductivity of the ion conductive film is not particularly limited, but examples include using the polymer film described later.

[0013] The bending radius of the ion conductive film included in the electrode complex of the present invention is preferably 0 mm or more and 10 mm or less, more preferably 0 mm or more and 5 mm or less, even more preferably 0 mm or more and 2 mm or less, and particularly preferably 0 mm or more and 1 mm or less. By the bending radius being within the above range, the flexibility and impact resistance of the battery are improved. The method for setting the ionic conductivity of the ion conductive film is not particularly limited, but examples include using the polymer film described later.

[0014] The ion conductive film included in the electrode complex of the present invention preferably contains a polymer solid electrolyte from the viewpoints of formability and the above bending radius. More specifically, polymers such as polyethers, polyacrylic acids, polyvinyl alcohols, polyamides, polyesters, fluororesins, polyimides, polyketones, polystyrenes, polycarbonates, polyurethanes, polythioureas, polyvinyl pyrrolidones, polyacrylonitriles, polysulfones, polyamines, and polysulfides, as well as derivatives and mixtures thereof, are preferably used.

[0015] In one aspect of the present invention, the porosity is 0% or more and 10% or less, and the permeation rate of 1M LiPF6PC (lithium hexafluorophosphate propylene carbonate) electrolyte determined by the measurement method described later is 0 mg / cm 2 / day or more and 0.1 mg / cm 2An ion-conducting membrane with a porosity of less than / day is an example. By having the porosity and 1M LiPF6PC electrolyte permeation rate within the above range, using this ion-conducting membrane as a separator in a two-liquid battery can suppress electrolyte mixing for a long period of time, providing a secondary battery with high energy density and long lifespan. The method for achieving the above range for porosity and 1M LiPF6PC electrolyte permeation rate is not particularly limited, but one example is the use of a polymer membrane as described later. Furthermore, it is preferable to use the above-mentioned ion-conducting membrane in the electrode composite of the present invention.

[0016] The ion-conducting membrane included in the electrode composite of the present invention preferably has a maximum free volume radius of 0.15 nm to 0.38 nm, and particularly preferably 0.15 nm to 0.36 nm. Being within this range allows for high ion conductivity while maintaining liquid separation properties. The method for achieving the maximum free volume radius within this range is not particularly limited, but one example is the use of a polymer membrane, as described later. Furthermore, the electrode composite of the present invention preferably uses the above-mentioned ion-conducting membrane.

[0017] The ion-conducting membrane included in the electrode composite of the present invention preferably has an inorganic solid electrolyte layer. Having this layer makes it possible to suppress side reactions within the battery. Specific examples of inorganic solid electrolytes include sulfide-based electrolytes, oxide-based electrolytes, phosphate-based electrolytes, and halide-based solid electrolytes, and more specifically, Li 1+x Al x Ti 2-x (PO4)3(0 <x<2)、Li 1+x Al x Ge 2-x (PO4)3(0 <x<2)、Li 1+x+y Al x Ti 2-x Si y P 3-y O 12 (0 <x<2, 0<y<3)、Li 3-x PO y N z (0 <x<3,0<y,0<z),La 2 / 3-x Li 3x TiO3(0 <x<2 / 3)、La 0.5LiTiO3, Li7La3Zr2O 12 These include the following. Among them, it is preferable to use an oxide solid electrolyte with excellent atmospheric stability as the inorganic solid electrolyte layer. The inorganic solid electrolyte layer may also be included in an ion conductive film or an electrode composite, but it is preferable to include it in an ion conductive film in order to reduce the interfacial resistance of the electrode and promote a uniform reaction within the electrode surface. The method for constructing the electrode composite as described above is not particularly limited, but one example is to use an ion conductive film on which an inorganic solid electrolyte has been sputtered onto the surface.

[0018] The thickness of the solid electrolyte layer included in the electrode composite of the present invention is preferably 10 nm to 2000 nm. The inorganic solid electrolyte layer of the present invention is a region mainly composed of the inorganic solid electrolyte described later. In the present invention, "mainly composed of the inorganic solid electrolyte" means that it contains 50% by mass or more of the inorganic solid electrolyte. The inorganic solid electrolyte in the inorganic solid electrolyte region is preferably 60% by mass to 100% by mass, more preferably 70% by mass to 100% by mass, even more preferably 80% by mass to 100% by mass, even more preferably 90% by mass to 100% by mass, and particularly preferably 95% by mass to 100% by mass. The thickness of the inorganic solid electrolyte layer is preferably 10 nm to 1000 nm, more preferably 10 nm to 400 nm, even more preferably 50 nm to 400 nm, even more preferably 50 nm to 150 nm, and particularly preferably 50 nm to 100 nm. By keeping the thickness of the inorganic solid electrolyte layer within the above range, an ion-conducting membrane with liquid separation properties can be created while maintaining membrane density and resistance. When such an ion-conducting membrane is used in a two-liquid battery, a battery with excellent battery capacity and gravimetric energy density, or a secondary battery with excellent battery capacity, cycle characteristics, and gravimetric energy density can be provided. The thickness of the inorganic solid electrolyte layer can be controlled by various conditions such as the sputtering time and output of the sputtering method.

[0019] The electrode composite of the present invention preferably has an electrolyte between the electrode and the ion-conducting membrane. Including an electrolyte between the electrode and the ion-conducting membrane improves ion transport between the electrode and the ion-conducting membrane, thereby improving battery life. The method of constructing the electrode composite is not particularly limited, but examples include sealing the electrode in a bag-like manner with an ion-conducting membrane and pouring in the electrolyte, or sealing a microporous membrane containing the electrolyte and the electrode in a bag-like manner with an ion-conducting membrane. The electrolyte of the present invention is an electrolyte that is liquid at 25°C. From the viewpoint of ion conductivity, it is preferable to use a solution obtained by dissolving the electrolyte in a solvent described later. Specific electrolytes that are preferably used include alkali metals, particularly lithium halides, perchlorates, thiocyanates, boron fluorides, phosphorus fluorides, arsenic fluorides, aluminum fluorides, and trifluoromethyl sulfates. For example, one or more salts of lithium salts (electrolytes) such as lithium perchlorate (LiClO4), lithium hexafluoride phosphate (LiPF6), lithium tetraborate (LiBF4), lithium arsenide hexafluoride (LiAsF6), lithium trifluoromethanesulfonate (LiCF3SO3), lithium bis(trifluoromethanesulfonyl)imide [LiN(CF3SO2)2], lithium bromide (LiBr), lithium bis(oxalate) borate, lithium difluoro(oxalate) borate, lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and lithium bis(pentafluoroethanesulfonyl)imide can be used, but lithium hexafluoride phosphate, lithium bis(fluorosulfonyl)imide (LiFSI), and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) are preferred. When the electrode composite of the present invention is used as a negative electrode, it is more preferable to use LiFSI or LiTFSI as the electrolyte in the electrolyte in order to suppress the decomposition of the electrolyte. When the electrode composite of the present invention is used as a positive electrode, it is more preferable to use lithium hexafluoride phosphate as the electrolyte in order to suppress the decomposition of the electrolyte.

[0020] The concentration of the electrolyte is preferably between 0.5 mol / L and 5.0 mol / L, more preferably between 1.0 mol / L and 5.0 mol / L, even more preferably between 1.0 mol / L and 4.0 mol / L, and particularly preferably between 2.0 mol / L and 4.0 mol / L. A concentration of the electrolyte within this range results in good ionic conductivity.

[0021] The solvent used in the electrolyte is not particularly limited and any organic solvent used in conventional lithium-ion batteries can be used. Specifically, cyclic esters, linear esters, cyclic ethers, linear ethers, etc. can be used, such as ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), vinylene carbonate (VC), dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (MEC), γ-butyrolactone (γBL), 2-methyl-γ-butyrolactone, acetyl-γ-butyrolactone, γ-valerolactone, 1,2-dimethoxyethane (DME), 1,2-ethoxyethane, diethyl ether, ethylene glycol dialkyl ether, diethylene glycol dialkyl ether, triethylene glycol dialkyl ether, tetraethylene glycol dialkyl ether, dipropyl carbonate, methyl butyl carbonate, methyl propyl carbonate, etc. Organic solvents such as butyl butyl carbonate, ethyl propyl carbonate, butyl propyl carbonate, alkyl propionate, dialkyl malonate, alkyl acetate, tetrahydrofuran (THF), alkyltetrahydrofuran, dialkylalkyltetrahydrofuran, alkoxytetrahydrofuran, dialkoxytetrahydrofuran, 1,3-dioxolane, alkyl-1,3-dioxolane, 1,4-dioxolane, 2-methyltetrahydrofuran, dimethyl sulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane, acetonitrile, nitromethane, methyl formate, methyl acetate, methyl propionate, ethyl propionate, triester phosphate, N-methyl-2-pyrrolidone, sulfolane, water, and derivatives and mixtures thereof are preferably used. When the electrode composite of the present invention is used as a negative electrode, cyclic ethers, chain ethers, etc., are preferably used as the solvent for the electrolyte in order to suppress the decomposition of the electrolyte. When using the electrode composite of the present invention as a positive electrode, it is more preferable to use cyclic esters, linear esters, etc., as the solvent for the electrolyte in order to suppress the decomposition of the electrolyte.More specifically, preferred organic solvents include ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (MEC), acetonitrile, sulfolane, water, and derivatives or mixtures thereof.

[0022] In the electrode composite of the present invention, it is preferable that the electrode is sealed with only the ion-conducting film, or with only the ion-conducting film and an adhesive material. This configuration makes it possible to reduce the interface between different materials, especially the adhesive interface, and to maintain the separation of the liquids in the two-liquid battery for a long period of time. Specific examples of adhesive materials include epoxy resin, heat sealant, urethane resin, acrylate resin, and metal foil.

[0023] In the electrode composite of the present invention, it is preferable that the electrode is metallic lithium, a silicon anode, or a negative electrode current collector. By using metallic lithium, a silicon anode, or a negative electrode current collector as the electrode, it is possible to use it as a negative electrode with high energy density. A specific example of a negative electrode current collector is copper foil. From the viewpoint of the Coulomb efficiency and energy density of the battery, metallic lithium is more preferable. From the viewpoint of electrode sealing properties and handling ease, copper foil is more preferable.

[0024] In the electrode composite of the present invention, it is preferable that the electrode active material is an NCM cathode (a ternary cathode mainly composed of nickel, cobalt, and manganese), lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate, lithium iron manganese phosphate, NCA cathode (a ternary cathode mainly composed of nickel, cobalt, and aluminum), lithium-rich layered oxide, lithium-rich spinel oxide, lithium-rich olivine-type oxide, and derivatives or mixtures thereof. In particular, it is more preferable that the electrode is an NCM cathode, lithium cobalt oxide, lithium manganese oxide, lithium iron manganese phosphate, NCA cathode, lithium-rich layered oxide, lithium-rich spinel oxide, lithium-rich olivine-type oxide, and derivatives or mixtures thereof, as these result in a higher potential and improved energy density of the battery. By using the above electrodes, it is possible to use them as a cathode with high energy density.

[0025] The electrode composite of the present invention preferably has tab leads for extracting current from the electrodes and applying voltage, and preferably a portion of the tab leads is located outside the ion-conducting film sealed to the electrodes. The method for achieving the above configuration is not particularly limited, but one example is using electrodes with tab leads. Furthermore, in the electrode composite of the present invention, it is preferable that the tab leads located outside the ion-conducting film are partially covered with an insulating material, more preferably that the insulating material has electrolyte resistance, and even more preferably that it has heat resistance. With the above configuration, in a two-liquid battery using the electrode composite of the present invention, it is possible to suppress the decomposition of the electrolyte by preventing the tab leads from coming into contact with the electrolyte of the other counter electrode.

[0026] One embodiment of the battery according to the present invention is a battery comprising an electrode composite of the present invention and a counter electrode of the electrode composite. With this configuration, mixing of electrolytes of different compositions can be suppressed for a long period of time in a battery composed of such electrolytes, and a secondary battery with high energy density and long lifespan can be provided. Furthermore, short circuits between the electrode and the counter electrode constituting the electrode composite are also prevented, and since this facilitates the manufacture of stacked batteries, the battery of the present invention is preferably a stacked battery. In addition, since the electrode composite of the present invention is flexible, the battery of the present invention is preferably a wound battery.

[0027] In the present invention, it is preferable that the electrode composite and the counter electrode are sealed in a bag-like structure with an outer material. With this configuration, it is possible to create a stacked battery in which multiple electrode composites and counter electrodes are stacked inside the outer material, thereby improving the energy density of the battery. Furthermore, in a two-liquid battery, it is possible to inject the electrolyte on the counter electrode side in a single step, thereby improving production efficiency and reducing production costs. The method for achieving the above configuration is not particularly limited, but one example is to cover the electrode composite and counter electrode with an aluminum pouch with heat sealant as the outer material and heat seal it.

[0028] From the viewpoint of energy density, the battery according to the embodiment of the present invention is preferably a metallic Li anode battery, a silicon anode battery, a clay battery, a semi-solid battery, a solid battery, a fully solid battery, a sulfur battery, or an air battery. Among sulfur batteries and air batteries, lithium sulfur batteries and lithium air batteries are more preferred.

[0029] The positive electrode of the battery according to an embodiment of the present invention includes, as a positive electrode active material, at least one transition metal selected from manganese, cobalt, nickel, and titanium, and a lithium metal oxide containing lithium (such as lithium cobalt oxide or lithium manganese oxide), and known positive electrode active materials such as oxygen.

[0030] The negative electrode of the present invention is not particularly limited as long as it is a material capable of intercalating and releasing metal ions as an active material. For example, known negative electrode active materials such as Li, Sn, Si, In, lithium alloy particles (lithium alloy particles of lithium with titanium, magnesium, or aluminum, etc.), and carbon-based materials (carbon, hard carbon, soft carbon, and graphite, etc.) can be used as appropriate. Among these, the use of metallic lithium is preferable from the viewpoint of increasing the energy of the battery. Furthermore, the lithium equivalent concentration of the negative electrode is preferably 1.0 mol / L or more for the entire negative electrode. If the lithium equivalent concentration is 1.0 mol / L or more, the capacity can be increased. The upper limit is not particularly limited, but is substantially 100 mol / L or less.

[0031] The battery of the present invention is not particularly limited and can use organic solvents used in conventional lithium-ion batteries. Furthermore, the electrolyte to which the present invention is applied can be solid or liquid, but it is preferable to use an electrolyte solution in order to increase the contact area with the electrodes. The solvents used in the above electrolyte include cyclic esters, linear esters, cyclic ethers, linear ethers, etc. Specifically, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), vinylene carbonate (VC), dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (MEC), γ-butyrolactone (γBL), 2-methyl-γ-butyrolactone, acetyl-γ-butyrolactone, γ-valerolactone, 1,2-dimethoxyethane (DME), 1,2-ethoxyethane, diethyl ether, ethylene glycol dialkyl ether, diethylene glycol dialkyl ether, triethylene glycol dialkyl ether, tetraethylene glycol dialkyl ether, dipropyl carbonate, methyl butyl carbonate, methyl propyl carbonate Organic solvents such as ionate, ethyl butyl carbonate, ethyl propyl carbonate, butyl propyl carbonate, alkyl propionate, dialkyl malonate, alkyl acetate, tetrahydrofuran (THF), alkyl tetrahydrofuran, dialkylalkyl tetrahydrofuran, alkoxy tetrahydrofuran, dialkoxy tetrahydrofuran, 1,3-dioxolane, alkyl-1,3-dioxolane, 1,4-dioxolane, 2-methyltetrahydrofuran, dimethyl sulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane, acetonitrile, nitromethane, methyl formate, methyl acetate, methyl propionate, ethyl propionate, triester phosphate, N-methyl-2-pyrrolidone, sulfolane, water, and derivatives or mixtures thereof are preferably used.

[0032] Preferably, electrolytes included in the electrolyte solution are alkali metals, particularly lithium halides, perchlorates, thiocyanates, boron fluorides, phosphorus fluorides, arsenic fluorides, aluminum fluorides, trifluoromethyl sulfates, and the like. For example, one or more salts of lithium salts (electrolytes) such as lithium perchlorate (LiClO4), lithium hexafluoride phosphate (LiPF6), lithium tetraborate (LiBF4), lithium arsenide hexafluoride (LiAsF6), lithium trifluoromethanesulfonate (LiCF3SO3), lithium bis(trifluoromethanesulfonyl)imide [LiN(CF3SO2)2], lithium bromide (LiBr), lithium bis(oxalate) borate, lithium difluoro(oxalate) borate, lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and lithium bis(pentafluoroethanesulfonyl)imide can be used, but lithium hexafluoride phosphate, lithium bis(fluorosulfonyl)imide (LiFSI), and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) are preferred.

[0033] The non-aqueous electrolyte of the battery according to the embodiment of the present invention preferably contains at least one type of metal ion, and the concentration of the metal ion is preferably 0.5 mol / L or more and 7.0 mol / L or less. The metal ion is preferably a metal ion that moves between the positive and negative electrodes when the battery is charged and discharged. Specifically, in the case of a lithium-ion battery, it is a lithium ion, and in the case of a sodium battery, it is a sodium ion. The metal ion concentration is preferably 0.5 mol / L or more and 5.0 mol / L or less, and more preferably 1.0 mol / L or more and 5.0 mol / L or less. Being within this range allows the battery to exhibit good battery characteristics. From the viewpoint of battery operability, the metal ion is preferably a lithium ion, sodium ion, magnesium ion, potassium ion, or calcium ion, more preferably a lithium ion, sodium ion, or magnesium ion, and particularly preferably a lithium ion. Additives may also be used in the non-aqueous electrolyte as needed. Examples of additives include vinylene carbonate, fluoroethylene carbonate, ethylene sulfite, 1,4-butanesultone, propanesultone, 2,4-difluoroanisole, biphenyl, and cyclohexylbenzene, and one or more of these may be used.

[0034] The battery of the present invention preferably has two or more electrolytes with different compositions, and more preferably the electrode composite has an electrolyte (electrolyte A) between the ion-conducting membrane and the electrode, and an electrolyte (electrolyte B) with a different composition from electrolyte A between the electrode composite and the counter electrode. With the above configuration, it is possible to use an electrolyte that matches the potential of each electrode and the corrosiveness of the current collector, making it possible to provide a secondary battery with higher energy density and longer lifespan. Specifically, it is preferable that the electrolyte on the positive electrode side contains acetonitrile, propylene carbonate, etc., and it is preferable that the electrolyte on the negative electrode side contains LiFSI or LiTFSI.

[0035] Next, a method for manufacturing a battery according to an embodiment of the present invention will be described below.

[0036] The material used as the current collector layer in the battery according to the embodiment of the present invention is not particularly limited, but for example, metal foil made of gold, silver, aluminum, copper, stainless steel, nickel, titanium, alloys thereof, carbon-based materials, etc. can be used.

[0037] The electrode mixture layer of the positive electrode of the battery according to the embodiment of the present invention may be a single component or may contain other components. As other components, known positive electrode active materials such as lithium metal oxides (such as lithium cobaltate or lithium manganeseate) containing at least one transition metal selected from manganese, cobalt, nickel, and titanium, and lithium, can be used as appropriate. Furthermore, the active material of the negative electrode electrode mixture layer is not particularly limited, but any material that can intercept and release metal ions, etc., is acceptable. For example, known negative electrode active materials such as Li, Sn, Si, In, lithium alloy particles (lithium alloy particles of lithium with titanium, magnesium, or aluminum, etc.), and carbon-based materials (carbon, hard carbon, soft carbon, and graphite, etc.) can be used as appropriate.

[0038] The secondary battery according to the embodiment of the present invention can be suitably used as a power source for electronic devices such as mobile phones and watches, electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), airplanes, UAMs and other vehicles, unmanned transport aircraft such as drones, flying objects such as HAPS (High Altitude Platform Stations), and large industrial equipment such as industrial cranes. It can also be suitably used as a power leveling device for solar cells and wind power generation equipment, as a power storage device for smart grids, as a stationary power source, and as a backup power source for data centers. Furthermore, it can be suitably used as a battery for use in special environments such as space.

[0039] In the ion-conducting membrane of the present invention, it is preferable that the polymer constituting the ion-conducting membrane has 20 mol% to 99 mol% of functional groups having an acid dissociation constant (pKa) of 5.0 or less or 8.0 or more in the repeating units of the polymer. Preferably, it is 40 mol% to 99 mol%, and more preferably 60 mol% to 99 mol%. The pKa in the present invention is the value in water at 25°C. Functional groups with a pKa of 5.0 or less or 8.0 or more interact with cations or anions in order to release or accept hydrogen ions. By having functional groups with a pKa of 5.0 or less or 8.0 or more within the above range, the interaction with cations or anions becomes appropriate, and the ion-conducting membrane containing such a polymer exhibits excellent salt dissociation and good ionic conductivity and cation transportability. Specific examples of functional groups with a pKa of 5.0 or less or 8.0 or more include sulfonic acid groups, phosphate groups, carboxylic acid groups, and amino groups. Polymers that have functional groups with a pKa of 5.0 or less or 8.0 or more within the above range are not particularly limited, but examples include polymers described later. While not limited to specific methods, each component of the polymer according to the embodiment of the present invention and its content can be analyzed by combining methods such as nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), and mass spectrometry (MS), elemental analysis, and single-crystal structure analysis for each component separated by a combination of methods such as redissolution, extraction, chromatography, distillation, liquid-liquid separation, and reprecipitation.

[0040] In the ion-conducting membrane of the present invention, it is preferable that the polymer constituting the ion-conducting membrane has an aromatic ring on its main chain. Polymers having an aromatic ring on their main chain are highly strong and therefore easily maintain high strength when formed into a thin film. Examples of such polymers include aromatic polyamides (aramids), aromatic polyimides, aromatic polyamide-imides, aromatic polyether ketones, aromatic polyether ether ketones, aromatic polyarylates, aromatic polysulfones, aromatic polyethersulfones, aromatic polyetherimides, aromatic polycarbonates, aromatic thioamides, and aromatic thioureas. Alternatively, a blend of multiple polymers may be used. Among these, aromatic polyamides, aromatic polyimides, or aromatic polyamide-imides are more preferable, and aromatic polyamides are particularly preferable, because they easily maintain high strength when formed into a thin film. That is, it is preferable that the polymer according to the embodiment of the present invention contains an aromatic polyamide.

[0041] In the present invention, it is preferable that the polymer constituting the film contains a polymer having one of the following chemical formulas (I) to (III), and examples of aromatic polyamides include those having repeating units represented by the following chemical formula (I), aromatic polyimides by the following chemical formula (II), and aromatic polyamideimides by the following chemical formula (III).

[0042] [ka]

[0043] [ka]

[0044] [ka]

[0045] Furthermore, the bonds constituting the main chain on the aromatic ring may be meta-oriented or para-oriented. In addition, some of the hydrogen atoms on the aromatic ring may be substituted with any group.

[0046] Specific examples of aromatic diamines that constitute aromatic polyamides, aromatic polyimides, or aromatic polyamideimides include paraphenylenediamine, metaphenylenediamine, orthophenylenediamine, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 2,2'-ditrichloromethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzophenone, and 3,3'-diaminobenzophenone. Examples include, but are not limited to, non-, 2-chloro-1,4-phenylenediamine, 2-trifluoromethyl-1,4-phenylenediamine, 5-trifluoromethyl-1,3-phenylenediamine, 4,'-oxybis(3-trifluoromethyl)aniline, 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene, 1,5'-naphthalenediamine, 4,4'-diaminodiphenylsulfone, and 1,4-bis(4-aminophenoxy)benzene. From the viewpoint of achieving both ionic conductivity and liquid separation properties, 4,4'-diaminodiphenyl ether and 1,4-bis(4-aminophenoxy)benzene are particularly preferred.

[0047] The ion-conducting membrane of the present invention preferably contains at least one of the aforementioned functional groups: a sulfonic acid group, a phosphoric acid group, and a carboxylic acid group. By including the above polymer, the functional group interacts with the cation, thereby improving the dissociability of the salt and increasing the number of carrier ions, and thus improving the ionic conductivity. It is more preferable to include at least one of the sulfonic acid group and phosphoric acid group with a low pKa, and it is particularly preferable to include a sulfonic acid group. The above polymer is not particularly limited, but examples include polymers described later.

[0048] The protons of sulfonic acid groups, phosphate groups, and carboxylic acid groups contained in the polymer constituting the ion-conducting film of the present invention are preferably substituted with alkali metal cations. By substituting the protons of the above functional groups with alkali metal cations, the number of carrier ions increases, improving ionic conductivity. The alkali metal cation is more preferably lithium, sodium, or potassium, and particularly preferably lithium. The method of substituting the protons of the functional groups with alkali metal cations is not particularly limited, but one example is the method of adding a metal salt, which will be described later.

[0049] The polymer constituting the ion-conducting membrane of the present invention preferably contains an amino group among the functional groups described above. It is believed that by including the above polymer, the functional group interacts with anions, trapping the anions and thereby increasing the cation transport rate. The above polymer is not particularly limited, but examples include the polymers described later.

[0050] From the viewpoint of improving ionic conductivity, the ion-conducting membrane of the present invention preferably contains 10% to 99% by mass of electrolyte salt. By keeping the electrolyte salt content within the above range, the ionic conductivity increases with increasing carrier ion numbers. More preferably, the electrolyte salt content is 15% by mass or more. Furthermore, since a high electrolyte salt content may reduce liquid separation performance, it is preferable to contain 60% by mass or less, more preferably 40% by mass or less, and most preferably 20% by mass or less. Therefore, from the viewpoint of achieving both ionic conductivity and liquid separation performance, a electrolyte salt content of 15% to 20% by mass is a desirable range. The cations constituting the above electrolyte salt are preferably one or more metal element ions selected from the group consisting of lithium ions, sodium ions, magnesium ions, zinc ions, and aluminum ions. Furthermore, the statement that an ion-conducting membrane contains 35% to 99% by mass of electrolyte salts means that the ion-conducting membrane contains one or more metal elements selected from the group consisting of lithium, sodium, magnesium, zinc, and aluminum, and that the total content of all electrolyte salts is within the above range. The method for achieving the above range of electrolyte salt content is not particularly limited, but one example is the method of adding metal salts as described later.

[0051] One aspect of the present invention is an ion-conducting film containing anions having an ionic radius of 0.20 nm to 0.60 nm. Preferably, it is 0.25 nm to 0.60 nm, and particularly preferably 0.30 nm to 0.60 nm. This is because, by having an ionic radius of the contained anions within the above range, the charge density of the anions decreases, the electrostatic interaction between cations and anions weakens, and the degree of ion dissociation increases. Specific examples of anions with an ionic radius of 0.20 nm to 0.60 nm are bis(trifluoromethanesulfonylamide) ions, bis(fluorosulfonylamide) ions, trifluorosulfonate ions, hexafluorophosphate ions, and perchlorate ions. These lithium salts may be used individually or in combination of two or more. The method for containing anions with an ionic radius of 0.20 nm to 0.60 nm is not particularly limited, but for example, a method of adding a metal salt, as described later, can be used.

[0052] One aspect of the present invention is an ion-conducting film having a haze of 0.0% to 30.0%. More preferably, it is 0.0% to 5.5%, even more preferably 0.0% to 4.5%, and particularly preferably 0.0% to 1.0%. Having the haze within the above range results in a uniform film with good ion conductivity and electrolyte blocking performance. The method for achieving the haze within the above range is not particularly limited, but for example, it is preferable to form the ion-conducting film using a polymer described later.

[0053] In embodiments of the present invention, the ion-conducting film preferably has a cation transport number of 0.5 to 1.0, more preferably 0.6 to 1.0, even more preferably 0.7 to 1.0, and particularly preferably 0.8 to 1.0. Having a cation transport number within the above range suppresses resistance increases due to polarization and decreases in liquid separation properties, thereby enabling the development of good battery characteristics. The cation transport number can be evaluated using known methods employing AC impedance and DC methods.

[0054] The air permeability resistance of the ion-conducting film according to the embodiment of the present invention is 0 or more and 1.0 × 10 -4 (100 cc / second) or less is preferable. The air permeability resistance is 1.0 × 10 -4 By reducing the flow rate to less than 100 cc / second, physical through-holes are often created, which can block the penetration of dendrites and other materials. To achieve the desired air permeability resistance, it is preferable to form an ion-conducting film using the polymer described later.

[0055] The ion-conducting film of the present invention preferably has a non-porous region. A non-porous region is defined in the cross-sectional image of the ion-conducting film obtained by field emission scanning electron microscopy (FE-SEM) in the measurement method described later, where a straight line perpendicular to the interface is drawn from one interface to the other interface, and the number of voids of 50 nm or more intersecting the line is determined, and the region has 10 or fewer voids. In the present invention, having a non-porous region means that the thickness of the non-porous region is 0.5 μm or more. When the ion-conducting film is a composite film consisting of a non-porous region and a microporous film, the point where the distribution and size of voids in the thickness direction begin to change is considered the interface. Having a non-porous region improves the performance of blocking the permeation of substances other than ions that contribute to battery operation, making it possible to increase battery capacity and lifespan.

[0056] The ion-conducting film of the present invention preferably has a non-porous region thickness of 0.1 μm or more and less than 10 μm. By keeping the thickness of the non-porous region below the aforementioned upper limit, it is possible to suppress the resistance of the ion-conducting film from becoming too high in battery characteristics, and the weight can be reduced, making it suitable for use as a battery for flying vehicles where weight reduction is required. The thickness of the non-porous region is preferably 5 μm or less, and particularly preferably 3 μm or less. Furthermore, if the thickness of the non-porous region is too small, the battery cycle life will decrease, so it is preferably 0.5 μm or more, and particularly preferably 1.0 μm or more. The method for setting the thickness of the non-porous region within the above range is not particularly limited, but for example, it can be done by setting the concentration of the solution for forming the ion-conducting film within the range described later.

[0057] The ion-conducting membrane of the present invention preferably has a non-porous region and a microporous membrane, and is particularly preferably a composite membrane having a non-porous region and a microporous membrane. The method for forming the composite membrane is not particularly limited, but one example is a method of coating at least one side of the microporous membrane with a polymer using the method described later. Examples of the microporous membrane include a porous membrane having voids inside, a nonwoven fabric, or a porous membrane sheet made of a fibrous material. The material constituting the microporous membrane is preferably a resin that is electrically insulating, electrically stable, and stable in non-aqueous electrolytes.

[0058] The ion-conducting membrane of the present invention may contain other components that act as ion conduction aids, as long as they do not hinder the effects of the present invention. Examples include inorganic solid electrolytes, ionic liquids, and lithium salts.

[0059] The ion-conducting membrane of the present invention preferably has a maximum free volume radius of 0.15 nm to 0.38 nm. More preferably, it has a maximum free volume radius of 0.20 nm to 0.36 nm. By being within this range, high ion conductivity can be achieved while maintaining liquid separation properties. The method for achieving the maximum free volume radius within the above range is not particularly limited, but one example is the use of a polymer membrane as described later. Furthermore, the electrode composite of the present invention preferably uses the above-mentioned ion-conducting membrane.

[0060] The ion-conducting film of the present invention preferably has an inorganic solid electrolyte layer. Having this layer makes it possible to suppress side reactions within the battery. Specific examples of inorganic solid electrolytes include sulfide-based electrolytes, oxide-based electrolytes, phosphate-based electrolytes, and halide-based solid electrolytes, and more specifically, Li 1+x Al x Ti 2-x (PO4)3(0 <x<2)、Li 1+x Al x Ge 2-x (PO4)3(0 <x<2)、Li 1+x+y Al x Ti 2-x Si y P 3-y O 12(0 <x<2、0<y<3)、Li 3-x PO y N z (0 <x<3、0<y、0<z),La 2 / 3-x Li 3x TiO3(0 <x<2 / 3)、La 0.5 LiTiO3, Li7La3Zr2O 12 These include the following. Among them, it is preferable to use an oxide solid electrolyte with excellent atmospheric stability as the inorganic solid electrolyte layer. The inorganic solid electrolyte layer may also be included in an ion conductive film or an electrode composite, but it is preferable to include it in an ion conductive film in order to reduce the interfacial resistance of the electrode and promote a uniform reaction within the electrode surface. The method for constructing the electrode composite as described above is not particularly limited, but one example is to use an ion conductive film on which an inorganic solid electrolyte has been sputtered onto the surface.

[0061] In one embodiment of the ion-conducting film of the present invention, the thickness of the solid electrolyte layer is preferably 10 nm to 2000 nm. The inorganic solid electrolyte layer of the present invention is a region mainly composed of the inorganic solid electrolyte described later. In the present invention, "mainly composed of the inorganic solid electrolyte" means that it contains 50% by mass or more of the inorganic solid electrolyte. The inorganic solid electrolyte in the inorganic solid electrolyte region is preferably 60% by mass to 100% by mass, more preferably 70% by mass to 100% by mass, even more preferably 80% by mass to 100% by mass, even more preferably 90% by mass to 100% by mass, and particularly preferably 95% by mass to 100% by mass. The thickness of the inorganic solid electrolyte layer is preferably 10 nm to 1000 nm, more preferably 10 nm to 400 nm, even more preferably 50 nm to 400 nm, even more preferably 50 nm to 150 nm, and particularly preferably 50 nm to 100 nm. By keeping the thickness of the inorganic solid electrolyte layer within the above range, an ion-conducting membrane with liquid separation properties can be created while maintaining membrane density and resistance. When such an ion-conducting membrane is used in a two-liquid battery, a battery with excellent battery capacity and gravimetric energy density, or a secondary battery with excellent battery capacity, cycle characteristics, and gravimetric energy density can be provided. The thickness of the inorganic solid electrolyte layer can be controlled by various conditions such as the sputtering time and output of the sputtering method.

[0062] The following describes the method for producing the polymer and film of the present invention, using a fully aromatic polyamide as an example, but the present invention is not limited thereto.

[0063] The present invention also provides a method for producing a polymer by adding a Brønsted base to a monomer containing a functional group and / or its conjugate base group having a pKa of 5.0 or less or 8.0 or more, and then polycondensing the diamine monomer and the dicarboxylic acid dichloride monomer to obtain a polymer. In the above production method, by adding a Brønsted base, the functional group can be kept in the state of its conjugate base while the polymerization reaction proceeds, thereby suppressing side reactions and the termination of polymerization due to a decrease in solubility, and enabling the production of a high molecular weight polymer. There is no limit to the amount of Brønsted base added, but it is preferably 50 mol% or more relative to the functional group, and more preferably 100 mol% or more. Furthermore, there is no limit to the chemical species of Brønsted base to be added, but due to its affinity with the solvent and the resulting polymer, and its removeability, it is preferable to use a secondary amine and / or a tertiary amine, and more preferably a tertiary amine whose side chain is an alkyl group having 1 to 5 carbon atoms. More specifically, examples include triethylamine, diisopropylethylamine, and diethylamine.

[0064] Various known methods, such as solution polymerization and precipitation polymerization, can be used to obtain fully aromatic polyamides. For example, when polymerizing aromatic polyamides by solution polymerization, dicarboxylic acid dichloride and diamine can be used as raw materials and polymerized by reacting them at low temperatures in an aprotic solvent to which a Brønsted base has been added. Here, an aprotic solvent is a polar solvent that does not donate protons (hydrogen ions), and examples include N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylisobutylamide, 3-methoxy-N,N-dimethylpropanamide, tetrahydrofuran, γ-butyrolactone, ethyl acetate, acetonitrile, dimethylformamide, and dimethyl sulfoxide. To suppress the deactivation of dicarboxylic acid dichloride, it is preferable to keep the water content of the solvent used for polymerization at 500 ppm or less (by mass, the same applies below), and more preferably at 200 ppm or less. The polymerization reaction of fully aromatic polyamides is exothermic, but it is preferable to keep the temperature of the solution at 40°C or less during polymerization. If the temperature exceeds 40°C, side reactions may occur, preventing the degree of polymerization from reaching a sufficient level. It is preferable to keep the temperature of the solution below 30°C during polymerization.

[0065] When dicarboxylic acid dichloride and diamine are used as raw materials, hydrogen chloride is produced as a by-product during the reaction, resulting in a highly acidic solution of the resulting all-aromatic polyamide. This solution is highly corrosive and may be unusable in the manufacturing process of molded articles and films, as it can corrode metal substrates and other components. Methods for removing the by-product hydrogen chloride include adding a neutralizing agent during polymerization to neutralize and remove it, or precipitating and isolating the polymer. When neutralizing and removing hydrogen chloride during polymerization, for example, one method is to neutralize it with an inorganic neutralizing agent such as lithium carbonate, calcium carbonate, or calcium hydroxide. When neutralizing with an inorganic neutralizing agent, the solution contains an inorganic salt (e.g., lithium chloride) produced by the neutralization reaction. This inorganic salt ionizes in the solvent and coordinates to the amide group of the all-aromatic polyamide, acting as a solubility aid in the solvent, thus improving the pot life of the solution and suppressing polymer aggregation during molding. However, a washing step to remove the inorganic salt is required during the molding process, so it may not be usable depending on the dimensions of the molded article and / or film and the manufacturing process.

[0066] As a method for substituting the proton of the functional group of the polymer of the present invention with an alkali metal cation, polymerizing the polymer containing the functional group by the above method, and then reacting the polymer with a basic reagent, the H in the functional group + One method is to remove the functional group. Here, the basic reagent is such that the pKa of the conjugate acid generated from the basic reagent is the pKa of the functional group. a A more powerful reagent is preferred, for example, a metal hydride and / or metal carbonate. Specifically, examples include, but are not limited to, lithium hydride, sodium hydride, lithium carbonate, and sodium carbonate. When the conjugate base of the functional group is introduced into the polymer by this method, a metal cation is also included as its counterion. For this reason, when using the polymer of the present invention as a cation-conducting material, it is particularly preferable to react it with a basic reagent containing the target cation, as this can increase the amount of carriers contained in the film.

[0067] The viscosity ηinh of the polymer is preferably 0.3 to 7.0 dl / g. By setting the viscosity within this range, a polymer with excellent toughness, strength, and good ionic conductivity can be obtained. The viscosity η can be measured, for example, by the method described later.

[0068] Next, we will describe the film-forming stock solution (hereinafter referred to as the film-forming stock solution) used when manufacturing an ion-conducting membrane according to the embodiment of the present invention.

[0069] The polymer solution after polymerization may be used as the film-forming stock solution, but it is preferable to add a Li salt to the polymerization solution from the viewpoint of improving ionic conductivity. If the solution contains a large amount of unwanted substances such as neutralizing salts, it is preferable to isolate the polymer once and then redissolve it in an organic solvent such as the aprotic organic polar solvent mentioned above before use. The method for isolating the polymer is not particularly limited, but one method is to immerse the polymer solution after polymerization in a large amount of water or alcohol to extract the solvent and neutralizing salts into the water, separate only the precipitated polymer, and then dry it.

[0070] The concentration of polymer in the film-forming stock solution is preferably 3 to 30% by mass, and more preferably 4 to 20% by mass. Inorganic or organic particles may be added to the film-forming stock solution to improve the strength, heat resistance, and ion permeability of the resulting ion-conducting film, and to reduce the static friction coefficient, within a range that does not hinder the effects of the present invention. Examples of inorganic particles include wet and dry silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, alumina, aluminum hydroxide, magnesium hydroxide, magnesium carbonate, zinc carbonate, titanium oxide, zinc oxide (zinc oxide), antimony oxide, cerium oxide, zirconium oxide, tin oxide, lanthanum oxide, magnesium oxide, barium carbonate, zinc carbonate, basic lead carbonate (lead white), barium sulfate, calcium sulfate, lead sulfate, zinc sulfide, mica, titanium mica, talc, clay, kaolin, lithium fluoride, and calcium fluoride. Examples of organic particles include particles crosslinked using a polymer compound as a crosslinking agent. Examples of such crosslinked particles include crosslinked particles of polymethoxysilane compounds, crosslinked particles of polystyrene compounds, crosslinked particles of acrylic compounds, crosslinked particles of polyurethane compounds, crosslinked particles of polyester compounds, crosslinked particles of fluorine compounds, or mixtures thereof.

[0071] Next, a method for forming the ion-conducting film of the present invention will be described. The film-forming stock solution prepared as described above can be used to form a film using a so-called solution film-forming method. Solution film-forming methods include the dry-wet method, the dry method, and the wet method, and any of these methods may be used for film formation, but here we will explain using the dry-wet method as an example.

[0072] In the wet-dry method of film formation, the film-forming solution is extruded from a die onto a support such as a drum, endless belt, or film to form a film, which is then dried until it becomes self-retaining. Drying conditions can be, for example, within the range of 60-220°C for 60 minutes or less. However, the film after the dry process is peeled off the support and introduced into the wet process, where desalting and solvent removal are performed, and stretching, drying, and heat treatment are carried out as needed.

[0073] When stretching, the stretching ratio is preferably in the range of 0.8 to 8.0 times in terms of surface magnification (surface magnification is defined as the value obtained by dividing the area of ​​the stretched film by the area of ​​the film before stretching; a value of 1 or less means relaxed), and more preferably in the range of 1.0 to 5.0 times. When heat treatment is performed, the heat treatment is carried out at a temperature of 80°C to 500°C, preferably 130°C to 400°C, for several seconds to several tens of minutes. The ion-conducting film of the present invention obtained by the above manufacturing method can be used as an electrolyte film by inserting it directly between the positive and negative electrodes.

[0074] When the ion-conducting film of the present invention is a composite film having a non-porous region and a microporous film, the ion-conducting film and the microporous film obtained by the above-described film-forming method may be used in layers or bonded together. Furthermore, a method of applying the polymerized film-forming solution described above onto the microporous film and laminating it is also preferred, and any coating method such as a roll coater, slit coater, or dip coater can be used to apply the solution onto the microporous film.

[0075] The thickness of the ion-conducting film according to the embodiment of the present invention is not particularly limited, but is preferably 0.03 to 15 μm, more preferably 0.10 to 10 μm, even more preferably 0.20 to 5 μm, even more preferably 0.20 to 2 μm, and particularly preferably 0.20 to 1 μm. Furthermore, when the ion-conducting film of the present invention is a composite film of an ion-conducting film and a microporous film, the thickness ratio of the ion-conducting film to the microporous film is preferably 0.001 or more and 5 or less, and even more preferably 0.01 or more and 1 or less. By setting the thickness within the above range, the strength of the ion-conducting film is sufficient, there is no increase in resistance due to the film thickness, and it can be used suitably. The thickness of the ion-conducting film can be controlled by various conditions such as the concentration of the film-forming solution, the viscosity of the film-forming solution, the type and concentration of additives in the film-forming solution, the casting thickness of the ion-conducting film, the heat treatment temperature, and the stretching conditions.

[0076] The method for providing the inorganic solid electrolyte layer in the present invention is not particularly limited, but methods such as deposition, sputtering, or electroplating (hereinafter collectively referred to as the deposition method) under vacuum conditions or reduced pressure conditions with an inert gas such as argon gas sealed inside can be used, as can methods of bonding a metal foil or metal compound foil and an ion-conducting film directly or via an adhesive layer, or methods of providing a metal layer by electrochemical reaction using a solution containing a metal salt (electroplating method, electroless plating method). Among these, the deposition method is preferred from the viewpoint of continuously forming an inorganic solid electrolyte region on a film using an ion-conducting film.

[0077] When using the vacuum deposition method, it is preferable to pre-install the ion-conducting film in a vacuum chamber, then, while the unwound ion-conducting film is in close contact with a cooling roll, solidify and deposit heated and vaporized metal and / or metal compounds onto the surface of the ion-conducting film to form an inorganic solid electrolyte layer, and then wind it up again as a film roll.

[0078] Here, the inside of the vacuum chamber is 9.0 × 10 -3 Vacuum conditions below Pa, or conditions under reduced pressure with an inert gas such as argon gas sealed inside, can both be suitably used. Furthermore, the inorganic solid electrolyte layer may be formed by continuously performing two or more deposition processes, such as providing a first inorganic solid electrolyte layer by sputtering, followed by providing a second inorganic solid electrolyte layer by sputtering.

[0079] Vacuum deposition methods include induction heating deposition, resistance heating deposition, laser beam deposition, and electron beam deposition. Among these, electron beam deposition, laser beam deposition, and induction heating deposition are preferred because they generate a large amount of heat from the deposition source. The amount of heat generated by the deposition source needs to be large enough to form an inorganic solid electrolyte layer of the desired thickness, and the substrate surface temperature needs to be sufficiently high. However, since it is difficult to measure this directly, it is possible to determine whether the amount of heat is sufficient by confirming that the inorganic solid electrolyte layer after deposition is of the desired thickness.

[0080] However, if the heat generated by the deposition source is increased to the required amount, the temperature of the ion-conducting film will rise with the cooling function of a normal vacuum deposition method, potentially leading to thermal damage that degrades the mechanical properties of the ion-conducting film, and even the possibility of the ion-conducting film melting. Therefore, it is preferable to manage the cooling function during deposition to ensure that the ion-conducting film is cooled uniformly and that the temperature does not rise too much. Specifically, it is preferable to cool the deposition surface uniformly from the back using a cooling mechanism consisting of a metal plate or metal roll that has been sufficiently cooled with a refrigerant. To cool uniformly, it is essential to ensure that the ion-conducting film and the cooling mechanism are in close contact without any gaps. By improving the contact, thermal damage to the surface of the ion-conducting film can be reduced, and the deterioration of the mechanical properties of the ion-conducting film can be suppressed.

[0081] For example, if there is a scratch on the metal roll of the cooling mechanism, the scratched area becomes a gap, preventing the ion-conducting film from being cooled, thus increasing thermal damage to the ion-conducting film. Also, if foreign matter gets into the ion-conducting film and the metal roll of the cooling mechanism, the foreign matter prevents the ion-conducting film from being cooled, increasing thermal damage. When the heat output of the deposition source is increased to the required amount, scratches on the metal rolls and foreign matter contamination, which are acceptable in normal vacuum deposition methods, become problematic, so the control of scratches on the metal rolls and foreign matter contamination needs to be made even stricter.

[0082] In the present invention, when the inorganic solid electrolyte layer is to be of a desired thickness, a method of forming it in a single deposition (defined as the sequence of unwinding, deposition, and winding) is preferred from the viewpoint of productivity, resistance characteristics, and quality. However, for example, a thin film deposition process in which a 50 nm thick inorganic solid electrolyte region is formed in a single deposition is repeated 20 times (the above sequence is repeated 20 times) to form an inorganic solid electrolyte region with a total thickness of 1 μm.

[0083] Next, a method for producing an electrode composite according to an embodiment of the present invention (hereinafter referred to as the film-forming stock solution) will be described. Here, a method of encasing the electrode in a bag-like structure with an ion-conducting membrane will be used as an example.

[0084] When bonding ion-conducting films together, a solvent is applied to the bonding area, the films are joined, and then dried. Methods include using adhesives and applying low-melting-point thermoplastics such as polyolefins to the bonding portion in sheet form. Methods for lamination include sandwiching a porous resin and applying pressure and heat treatment, lamination by compression and heating, and lamination by applying a surface treatment to the ion-conducting film and then applying compression and heating. However, the method of applying a surface treatment to a porous film and then laminating by compression and heating is preferred because it has excellent chemical resistance and heat resistance, and the thickness when formed into a bag can be kept down. Surface treatments for the ion-conducting film include corona discharge treatment (including corona discharge treatment in various gas atmospheres), plasma treatment combining various conditions such as atmospheric pressure or low pressure, high temperature, and low temperature, and oxidation treatment using chemicals, ultraviolet light, electron beams, etc. Furthermore, in order to suppress the decrease in film strength of the ion-conducting film, low-temperature plasma treatment under various gas atmospheres that can be processed at relatively low temperatures is particularly preferred. Low-temperature plasma treatment as referred to here is a treatment performed by exposing the surface of the ion-conducting film to a discharge generated by applying a high voltage of DC or AC between electrodes. The pressure during this treatment is not particularly limited, and the treatment apparatus and discharge type can be selected as appropriate. Commonly used processing atmospheres include argon, helium, nitrogen, oxygen, air, carbon dioxide, and water vapor, but a water vapor-containing atmosphere is particularly preferred from the viewpoint of processing efficiency. The water vapor may also be diluted with other gases such as argon, helium, nitrogen, oxygen, air, or carbon dioxide. This surface treatment causes decomposition of amide groups and elimination reactions of nuclear substituents in the polymer, generating radicals on the film surface. These radicals then react with each other in the subsequent pressing process to bond the film.

[0085] Furthermore, the treatment strength of this surface treatment (a value calculated by applied voltage / (treatment speed × electrode width)) is 100 W·min / m 2 Preferably, the above is true. 100W·min / m 2 Below this level, radical generation may be insufficient, resulting in inadequate bonding and reduced elongation and bending properties. If the treatment intensity is too high, polymer degradation may progress, reducing heat resistance and liquid separation properties; therefore, the upper limit is 2,000 W·min / m 2Therefore, since the required bonding strength is obtained without the degradation of the polymer, the treatment strength is 300-1,000 W·min / m 2 It is preferable that it be so.

[0086] Next, the ion-conducting films that have undergone the above surface treatment are cut into predetermined shapes and stacked. The films can then be joined together by applying a hot plate press, vacuum press, heated roll press, ultrasonic continuous welding, or the like to the joints, which causes radicals to react and bond. The heat treatment temperature is preferably 180-350°C, as this suppresses the deterioration of physical properties while bonding, and more preferably 200-300°C. The press pressure is not particularly limited, but is generally in the range of 1-50 kg / cm². The press time varies depending on the thickness of the ion-conducting film and the press method, but is generally in the range of 1 minute to 10 hours at the heat treatment temperature. After pressing, it is preferable to allow the films to cool slowly before removing them in order to maintain their flatness. [Examples]

[0087] The present invention will be described in more detail below with reference to the following examples. The physical properties of the examples were measured by the following method.

[0088] (1) Logarithmic viscosity η inh The polymer was dissolved at a concentration of 0.5 g / dl in N-methylpyrrolidone (NMP) containing 2.5 mass% lithium bromide (LiBr), and the flow time was measured at 30°C using an Ubbelohde viscometer. The flow time of a blank LiBr 2.5 mass% / NMP without dissolving the polymer was measured in the same manner, and the logarithmic viscosity η was calculated using the following formula. inh It can be determined by calculating (dl / g). Logarithmic viscosity η inh (dl / g) = [ln(t / t0)] / 0.5 t0: Blank flow time (seconds) t: Sample flow time (seconds).

[0089] (2) Air permeability resistance Air permeability was measured using an Ouken-type air permeability meter (EGO-1T, manufactured by Asahi Seiko Co., Ltd.) with an air flow rate of 100cc. The upper limit of the device's measurement capacity is 99999 seconds / 100cc. The ion-conducting membrane was fixed in place to prevent wrinkles, and measurements were taken according to JIS P8117:2009. Three measurement points were set at equal intervals in the TD direction, and the reciprocal of the average value of the air permeability was used as the air permeability resistance (100cc / second).

[0090] (3) Cross-sectional structure (thickness of ion-conducting film, thickness of non-porous region) The ion-conducting films obtained in the examples were cross-sectionally cut using a cross-section polisher (JEOL SM-9010), and the cross-sections in the thickness direction in the width direction were coated with platinum to prepare observation samples. Next, the cross-sections of the samples were photographed at arbitrary magnifications using a field emission scanning electron microscope (FE-SEM) (JEOL JSM-6701F) to determine the thickness of the ion-conducting films. The acceleration voltage during observation was 2.0 kV. If the ion-conducting film was a composite film, the interface between the non-porous layer and the microporous layer was determined from the difference in cross-sectional structure or image contrast, and the thickness of each layer was determined. Next, the thickness of the non-porous region was determined from images taken at 10,000x magnification using the following method: A straight line perpendicular to the interface was drawn from one interface of the ion-conducting film to the other interface. The number of voids of 50 nm or more intersecting the line was determined, and if there were 10 or fewer voids, it was determined to be a non-porous region, and its thickness was calculated. If the ion-conducting film was a composite film consisting of a non-porous region and a microporous film, the point where the distribution and size of voids in the thickness direction began to change was considered the interface. Furthermore, when the length of a straight line perpendicular to the interface, extending from one interface to the other, is defined as l1, and the sum of the straight lines passing through voids of 50 nm or more is defined as l2, the minimum value of the following formula was calculated as the porosity. Porosity=100×l2 / l1 (%).

[0091] (4) Ionic conductivity After immersing the ion-conducting membrane in an electrolyte (1M LiTFSI ethylene carbonate (EC) / diethyl carbonate (DEC) = 1 / 1) for 24 hours, it was placed on a SUS304 electrode so as to cover the electrode portion. A non-aqueous electrolyte was then added dropwise, followed by the placement of the ion-conducting membrane. After adding the electrolyte dropwise again, the membrane was sandwiched between two SUS electrodes to create a laminate of electrode / ion-conducting membrane / electrode. The laminate was then fixed with a silicon plate to prevent shifting, and an evaluation cell was fabricated. For the fabricated cells, the AC impedance was measured at 25°C using an electrochemical test apparatus (Biologic, model number: SP-150) under the conditions of an amplitude of 10mV and a frequency of 1MHz-10mHz. The resistance value was read from the graph plotted on the complex plane and substituted into equation (1) to calculate the ionic conductivity. Five measurements were taken, and the average value was used as the ionic conductivity. σ = T0 / AR (1) σ: Ionic conductivity (S / cm) T0: Thickness of the ion-conducting film (cm) A: Electrode area (cm²) 2 ) R: Resistance value (Ω).

[0092] (5) Cation transport rate Using an HS cell (manufactured by Hosen Co., Ltd.), metallic lithium, an ion-conducting film used for the test, and metallic lithium were layered in an argon atmosphere (oxygen concentration 0.1 ppm or less, dew point -75°C or less). 300 μL of 1 M LiTFSI EC / DEC = 1 / 1 (volume ratio) was injected and the cell was sealed. For the fabricated cell, the AC impedance was measured at 25°C using an electrochemical test apparatus (Biologic, model number: SP-150) under conditions of amplitude 10 mV and frequency 1 MHz - 100 mHz, and the interfacial resistance (R0) was calculated from the second arc in the Cole plot. Next, the DC resistance of the electrode interface was measured, and the initial current value (I0) and steady-state current value (I1) were measured by applying a DC voltage (V). Finally, the AC impedance was measured at 25°C using an electrochemical test apparatus (Biologic, model number: SP-150) under conditions of amplitude 10mV and frequency 1MHz-100mHz, and the interfacial resistance (R1) was calculated from the second arc in the Cole plot. From the obtained values, the lithium transport fraction (τ) was calculated using the following formula.

[0093]

number

[0094] (6) Hayes The following measuring instruments were used for the measurements. Equipment: Direct-reading haze meter HGM-2DP (for C light source) (manufactured by Suga Test Instruments Co., Ltd.) Light source: Halogen lamp 12V, 50W Light receiving characteristics: 395~745nm Optical conditions: In accordance with JIS-K7105-1981.

[0095] (7)Bending radius Using a mandrel conforming to JIS-K5600-5-1 (1999), the following conditions were met, and the minimum cylindrical dimension at which fracture did not occur was defined as the bending radius. Sample dimensions: 50mm (short side) x 100mm (long side) Sample placement: Place the sample so that the folding line (cylindrical contact area) is 50 mm from the long side. Cylinder dimensions: radius 1mm to 10mm Folding speed: 1Hz Temperature: 23℃ Number of times: 5 If no fracture occurred even in a cylinder with a radius of 1 mm, the bending radius was considered to be 0 mm.

[0096] (8) Radius of free volume Positron annihilation lifetime measurements were performed under the following conditions. Equipment: Fuji Invac Co., Ltd. PALS-200A compact positron beam generator Positron source: 22Na-based positron beam Gamma-ray detector: BaF2 scintillator and photomultiplier tube Device constants: 234~246ps, 24.55ps / ch Beam intensity: 3 keV Measurement temperature: 23℃ Measurement atmosphere (degree of reduced pressure): 1 × 10⁻⁶ to 1 × 10⁻⁸ Pa Total count: Approximately 5,000,000 counts Sample size and pretreatment: The sample is attached to a 15mm square Si wafer and degassed under vacuum. The third component of the obtained positron annihilation lifetime curve was analyzed using the nonlinear least-squares program POSITRONFIT, and the maximum pore diameter when the free volume radius was plotted on the horizontal axis and the number of pores on the vertical axis was calculated as the maximum free volume radius (nm).

[0097] (8) Electrolyte permeation rate Under the dry room, paper (ASKUL recycled copy paper R100, 98μm thickness, 66g / m² basis weight) 2 ) Place an ion-conducting film on top, and the amount of electrolyte (cm 3 ) / electrolyte (cm 2 The electrolyte was dropped onto the paper so that the contact area of ​​the ion-conducting membrane with the paper was 0.8, and the permeation rate of the electrolyte was calculated from the change in the weight of the paper after standing for 72 hours. In addition, to prevent the electrolyte from seeping around the edges of the ion-conducting membrane and wetting the paper, the ion-conducting membrane and the paper were fixed from both sides with O-rings.

[0098] (9) Evaluation of electrolyte separation within the battery The fabricated two-liquid battery was disassembled after 24 or 72 hours, and the electrolyte, which would be used as the counter electrode (not an electrode composite), was dissolved in a heavy DMSO solution. 1 ¹H-NMR measurements were performed to obtain the NMR spectrum of the electrolyte. 1 For 1H-NMR, a superconducting FTNMR EX-270 (manufactured by JEOL Ltd.) was used to calculate the molar ratio of each solvent molecule from the peak intensity derived from each solvent molecule, thereby determining the ratio of the electrolyte components before preparation. ◎(Good liquid separation): 99% or more ○ (liquid separation passed): 95% or more × (Unsuitable for liquid separation): Less than 95%.

[0099] • Ion-conducting membrane F1 Dehydrated NMP (N-methyl-2-pyrrolidone, manufactured by Mitsubishi Chemical Corporation) was dissolved with 4,4'-diaminodiphenyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) as a diamine under a nitrogen stream and cooled to below 30°C. Then, while maintaining the system under a nitrogen stream and below 30°C, 2-chloroterephthaloyl chloride (manufactured by Nippon Light Metal Co., Ltd.), equivalent to 99 mol% of the total diamine, was added over 30 minutes. After the total addition, the mixture was stirred for approximately 2 hours to polymerize the aromatic polyamide. The resulting polymerization solution was neutralized with 97 mol% lithium carbonate (manufactured by Honjo Chemical Co., Ltd.) and 6 mol% diethanolamine (manufactured by Tokyo Chemical Industry Co., Ltd.) relative to the total acid chloride. The resulting polymer solution was added to purified water at a weight ratio of 10 times or more, and the solvent and neutralization salt were extracted into the water. After separating only the precipitated polymer, it was vacuum-dried at 90°C for 12 hours to obtain polymer powder. The logarithmic viscosity η of the obtained polymer was 2.5 dL / g. Subsequently, the polymer was redissolved in dehydrated NMP (manufactured by Mitsubishi Chemical Corporation) to a polymer concentration of 9% by mass, with LiTFSI being 0.33 times the amount of polymer by weight, to obtain a film-forming solution. The polymer solution P-3 was applied in a film-like manner to a PET film support, and dried in a 130°C hot air oven until the film became self-supporting. The film was then peeled off the support. Next, the peeled film was fixed to a metal frame and dried in a 130°C vacuum dryer for 1 hour. The characteristics of the obtained ion-conducting film are shown in Table 1.

[0100] • Ion-conducting membrane F2 Dehydrated NMP (N-methyl-2-pyrrolidone, manufactured by Mitsubishi Chemical Corporation) was dissolved with PDSA (1,4-phenylenediamine-4-sulfonic acid, manufactured by Sigma-Aldrich) at an amount equivalent to 60.0 mol% of the total diamine amount, and triethylamine (Fujifil Wako Pure Chemical Industries) at an amount equivalent to 200 mol% of the PDSA amount, under a nitrogen stream, and cooled to below 30°C. Next, under a nitrogen atmosphere and while maintaining the system at a temperature below 30°C, 2-chloroterephthaloyl chloride (manufactured by Nippon Light Metal Co., Ltd.) equivalent to 60.0 mol% of the total amount of diamine was added over 30 minutes, and after the total amount was added, the mixture was stirred for approximately 2 hours. Then, a solution of 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl (manufactured by Toray Fine Chemicals Co., Ltd.) equivalent to 40 mol% of the total amount of diamine was dissolved in anhydrous NMP and added. Then, 2-chloroterephthaloyl chloride (manufactured by Nippon Light Metal Co., Ltd.) equivalent to 39.2 mol% of the total amount of diamine was added over 30 minutes, and after the total amount was added, the mixture was stirred for approximately 2 hours to polymerize the aromatic polyamide. The resulting polymerization solution was neutralized with 97 mol% lithium carbonate (manufactured by Honjo Chemical Co., Ltd.) and 6 mol% diethanolamine (manufactured by Tokyo Chemical Industry Co., Ltd.) relative to the total amount of acid chloride. The obtained polymer solution was added to purified water at a weight ratio of 10 to 10 times, and the solvent and neutralizing salt were extracted into the water. After separating only the precipitated polymer, it was vacuum-dried at 90°C for 12 hours to obtain polymer powder. The logarithmic viscosity η of the obtained polymer was 2.6 dL / g. Subsequently, the polymer was redissolved in dehydrated NMP (manufactured by Mitsubishi Chemical Corporation) to a polymer concentration of 7 mass% and LiTFSI to 1.22 times the mass% of the polymer amount to obtain a film-forming solution. Using the film-forming solution, a PET film support was coated with a cast thickness of 130 μm, and the film was dried in a hot air oven at 130°C until it became self-supporting. The film was then peeled off the support. Next, the peeled film was fixed to a metal frame, immersed in a water bath for 15 minutes, and then air-dried at 130°C for 1 minute to obtain an ion-conducting film F2.

[0101] • Ion conductive film F3 Dehydrated NMP (N-methyl-2-pyrrolidone, manufactured by Mitsubishi Chemical Corporation) was dissolved with 4,4'-diaminodiphenyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) at an amount equivalent to 80.0 mol% of the total diamine amount under a nitrogen stream, and the mixture was cooled to below 30°C. Then, while maintaining the system under a nitrogen stream and below 30°C, 2-chloroterephthaloyl chloride (manufactured by Nippon Light Metal Co., Ltd.) at an amount equivalent to 80.0 mol% of the total diamine amount was added over 30 minutes, and after the total amount was added, the mixture was stirred for approximately 2 hours. Next, a solution of 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl (manufactured by Toray Fine Chemicals Co., Ltd.) dissolved in dehydrated NMP at an amount equivalent to 20 mol% of the total diamine amount was added, and then 2-chloroterephthaloyl chloride (manufactured by Nippon Light Metal Co., Ltd.) at an amount equivalent to 29.5 mol% of the total diamine amount was added over 30 minutes, and after the total amount was added, the mixture was stirred for approximately 2 hours to polymerize the aromatic polyamide. The obtained polymerization solution was neutralized with 97 mol% lithium carbonate (manufactured by Honjo Chemical Co., Ltd.) and 6 mol% diethanolamine (manufactured by Tokyo Chemical Industry Co., Ltd.) relative to the total amount of acid chloride. The obtained polymer solution was added to purified water at a weight ratio of 10 times or more, and the solvent and neutralization salt were extracted into the water. After separating only the precipitated polymer, it was vacuum dried at 90°C for 12 hours to obtain polymer powder. The logarithmic viscosity η of the obtained polymer was 3.1 dL / g. Subsequently, the polymer was redissolved in dehydrated NMP (manufactured by Mitsubishi Chemical Corporation) to a polymer concentration of 6 mass% and LiTFSI to 1.50 times the mass% of the polymer amount to obtain a film-forming solution. Using the film-forming solution, a cast thickness of 180 μm was applied to a PET film support, and the film was dried in a hot air oven at 130°C until the film became self-supporting. Then, the film was peeled off the support. Next, the peeled film was fixed to a metal frame, immersed in a water bath for 15 minutes, and then air-dried at 130°C for 1 minute. The resulting ion-conducting film was subjected to a single-wafer sputtering system SH-4501 (manufactured by ULVAC, Inc.) to create a Li film with a layer thickness of 65 nm. 1.5 Al 0.5 Ge 1.5 An ion-conducting film F3 was obtained by performing RF sputtering on only one side of (PO)3(LAGP). 1.5 Al 0.5 Ge 1.5A (PO)3 sintered body (manufactured by Toyoshima Seisakusho) was used as the sputtering target. The sputtering conditions were: target distance 11 cm, Ar atmosphere (pressure 0.55 Pa), and output 300 W.

[0102] • Ion-conducting membrane F4 An ion-conducting film was obtained by forming a film in the same manner as in Example 1, except that the diamine used was 1,4-bis(4-aminophenoxy)benzene. The viscosity η of the obtained polymer was 2.1 dL / g.

[0103] • Ion-conducting membrane F5 A polyethylene microporous membrane (Toray Industries, Inc., "Cetira" (registered trademark) F12CD1, 12 μm thickness, air permeability 160 seconds / 100 cc) as described in Table 1 was used. (Example 1) Electrode composite E1 The ion-conducting membrane F1 was cut into strips 70 mm wide and 100 mm long. A PET film was placed on top of the ion-conducting membrane F1 so that only 10 mm of each end in the long direction of the ion-conducting membrane was exposed, and the strips were fixed with Kapton tape. Low-temperature plasma treatment was performed on the surface with the PET film using the following method and conditions: An internal electrode type low-temperature plasma treatment apparatus was used, with Ar as the treatment gas, a pressure of 40 Pa, a treatment speed of 0.5 m / min, and a treatment intensity (value calculated as applied voltage / (treatment speed × electrode width)) of 1,000 W·min / m 2 Next, a PET film was placed on the ion-conducting film F1 such that only 10 mm of each of the short-side edges of the ion-conducting film was exposed, and it was fixed with Kapton tape. However, 10 mm x 10 mm of each of the four corners of the ion-conducting film were not exposed. Plasma treatment was performed on the surface on which the PET film was placed under the same conditions as above.

[0104] In a dry room, the processed surface was placed inward and folded in half to form a square. Next, a 10mm area from each of the two ends perpendicular to the fold direction was heat-sealed at 300°C for 30 seconds to create a bag-shaped ion-conducting film. Then, a lithium laminated product (Honjo Metal, metallic Li size 0.2mmt, current collector: copper foil 0.01mmt) was used as the electrode surface, and the metallic lithium laminated portion was cut to a size of 30mm x 30mm, while the copper foil portion for current collection was cut to a size of 5mm x 5mm for the tab bonding area. A copper tab with a width of 5mm and a thickness of 0.1mm was ultrasonically welded to the tab bonding area. The above-mentioned lithium laminated product with tab leads and a polyethylene microporous membrane (35mm x 35mm x 0.012mmt, air permeability 160 seconds / 100cc) immersed in a 4.0M LiFSI diethoxyethane (DEE) solution for 48 hours were placed together in a bag-shaped ion-conducting membrane so that the tab leads protruded. Next, a 10mm area from the edge of one side with an open opening was temporarily sealed at 250°C for 2 seconds while vacuuming with a vacuum sealer, and then the electrode composite was fabricated by pressing with a heat sealer at 300°C for 30 seconds.

[0105] (Example 2) Electrode composite E2 An electrode composite was fabricated in the same manner as in Example 1, except that F2 was used instead of F1 as the ion-conducting membrane.

[0106] (Example 3) Electrode composite E3 An electrode composite was fabricated in the same manner as in Example 1, except that copper foil was used instead of lithium laminate.

[0107] (Example 4) Electrode composite E4 Instead of lithium bonded products, NCM cathode (manufactured by Hosen Co., Ltd., cathode active material: Li (Ni 5 parts by mass, Mn 2 parts by mass, Co 3 parts by mass) O2, current collector Al, coating basis: 9.5 mg / cm²) 2 The electrode composite was prepared in the same manner as in Example 1, except that a 4.0M LiPF6PC solution was used instead of a copper tab, and a 4.0M LiFSI DEE solution was used instead of a 4.0M LiPF6PC solution.

[0108] (Example 5) Electrode composite E5 The electrode composite was prepared in the same manner as in Example 4, except that a 1.0 M LiPF6PC solution was used instead of a 4.0 M LiPF6PC solution.

[0109] (Example 6) Electrode composite E6 The electrode composite was fabricated in the same manner as in Example 1, except that an ion-conducting membrane F2 was used instead of F1.

[0110] (Example 7) Electrode composite E7 The ion-conducting film F3 was cut into strips 70 mm wide and 100 mm long. A PET film was placed on top of the ion-conducting film F3 so that only 10 mm of each end in the long-side direction of the ion-conducting film was exposed, and it was fixed with Kapton tape. Low-temperature plasma treatment was performed on the surface with the PET film using the following method and conditions: An internal electrode type low-temperature plasma treatment apparatus was used, with Ar as the treatment gas, a pressure of 40 Pa, a processing speed of 0.5 m / min, and a processing intensity (value calculated as applied voltage / (processing speed × electrode width)) of 1,000 W·min / m 2 Next, a PET film was placed on the ion-conducting film F1 so that only the edges of the ion-conducting film in the short-side direction were exposed by 10 mm each, and it was fixed with Kapton tape. However, the four corners of the ion-conducting film, each measuring 10 mm x 10 mm, were not exposed. Plasma treatment was performed on the surface on which the PET film was placed under the same conditions as above. Note that the above two plasma treatments were performed only on the surface that had not undergone sputtering treatment.

[0111] In a dry room, the plasma-treated surface was placed inward, and the material was folded in half to form a square. Next, a 10mm area from each of the two ends perpendicular to the fold direction was heat-sealed at 300°C for 30 seconds to create a bag-shaped ion-conducting film. Then, a single-sided lithium laminated product (Honjo Metal, metallic Li size 0.2mmt, current collector: copper foil 0.01mmt) was used as the electrode surface, and the metallic lithium laminated portion was cut to a size of 30mm x 30mm, while the copper foil portion for current collection was cut to a size of 5mm x 5mm for the tab bonding area. A copper tab with a width of 5mm and a thickness of 0.1mm was ultrasonically welded to the tab bonding area. The above-mentioned lithium laminated product with tab leads and a polyethylene microporous membrane (35mm x 35mm x 0.012mmt, air permeability 160 seconds / 100cc) immersed in a 4.0M LiFSI diethoxyethane (DEE) solution for 48 hours were placed together in a bag-shaped ion-conducting membrane so that the tab leads protruded. Next, a 10mm area from the edge of one side with an open opening was temporarily sealed at 250°C for 2 seconds while vacuuming with a vacuum sealer, and then the electrode composite was fabricated by pressing with a heat sealer at 300°C for 30 seconds.

[0112] (Comparative Example 1) Electrode Composite E8 An ion-conducting film F3 measuring 70 mm in width and 100 mm in length was folded in half to form a square. Next, a 10 mm area from each of the two ends perpendicular to the fold direction was heat-sealed using a heat sealer at a temperature of 250°C for 2 seconds to create a bag-shaped ion-conducting film. Then, a lithium laminated product (Honjo Metal, metallic Li size 0.2 mmt, current collector: copper foil 0.01 mmt) was used as the electrode surface, and the metallic lithium laminated portion was cut to a size of 30 mm x 30 mm, while the copper foil portion for current collection was cut to a size of 5 mm x 5 mm for the tab bonding area. A copper tab measuring 5 mm in width and 0.1 mm in thickness was ultrasonically welded to the tab bonding area. The above-mentioned lithium laminated material with tab leads and a polyethylene microporous membrane (35 mm × 35 mm × 0.012 mm thick, air permeability 160 seconds / 100 cc) immersed in a 4.0 M LiFSI diethoxyethane (DEE) solution for 48 hours were placed together in a bag-shaped ion-conducting membrane so that the tab leads protruded. Next, a 10 mm area from the end of one of the open sides was pressed together at a temperature of 250°C for 2 seconds to fabricate an electrode composite.

[0113] (Example 8) Battery B1 In a bag-shaped aluminum laminate film (internal size 90mm x 70mm), the following were layered in order: electrode composite E1, a polyethylene microporous membrane (35mm x 35mm x 0.012mmt, air permeability 160 seconds / 100cc) immersed in a 4.0M LiPF6PC solution for 48 hours, and an NCM positive electrode (electrode coating area 30mm x 30mm) with tab leads ultrasonically welded to it, with the tab leads protruding from the bag-shaped aluminum laminate film. The E1 and NCM positive electrodes were layered so that the metallic Li and NCM were close together. Next, the battery was fabricated by heat-sealing a 10mm area from the edge of one side of the opening while vacuum sealing it with a vacuum sealer.

[0114] (Example 9) Battery B2 The battery was fabricated in the same manner as in Example 7, except that electrode composite E2 was used instead of E1.

[0115] (Example 10) Battery B3 The following components were layered in the following order within a bag-shaped aluminum laminate film (internal size 60mm x 60mm): electrode composite E4, polyethylene microporous membrane (35mm x 35mm x 0.012mmt, air permeability 160 seconds / 100cc) immersed in 4.0M LiFSI DEE solution for 48 hours, and lithium laminated product (Honjo Metal, metallic Li size 30mm x 30mm x 0.2mmt, current collector: copper foil) with tab leads ultrasonically welded to the copper foil portion, with the tab leads protruding from the aluminum laminate film. The E4 and NCM positive electrodes were layered so that the metallic Li and NCM were close together. Next, the battery was fabricated by heat-sealing a 10mm area from the edge of one side of the opening while vacuum sealing it with a vacuum sealer.

[0116] (Example 11) Battery B4 The battery was fabricated in the same manner as in Example 8, except that E6 was used instead of E1 for the electrode composite.

[0117] (Example 12) Battery B5 The battery was fabricated in the same manner as in Example 8, except that E7 was used instead of E1 for the electrode composite.

[0118] (Comparative example 2) Battery B6 The battery was fabricated in the same manner as in Example 7, except that E6 was used instead of E1 for the electrode composite.

[0119] [Table 1]

[0120] [Table 2]

[0121] [Table 3] [Explanation of Symbols]

[0122] 1: Plasma-treated surface (1st time) 2: Plasma-treated surface (second time) 3: Fold 4: Tabread 5: Microporous membrane impregnated with electrolyte solution 6: Lithium bonded product (the microporous film side is lithium metal) 7: Weld between lithium laminated product and tab lead 8: Opposite 9: Electrode complex 10: Bag-shaped laminating film 11: Adhesive portion of the laminating film

Claims

1. An electrode composite comprising an ion-conducting membrane and an electrode, wherein the porosity of the ion-conducting membrane is 0% or more and 10% or less, and the electrode is enclosed by the ion-conducting membrane.

2. The electrode composite according to claim 1, wherein the bending radius of the ion-conducting membrane is 0 mm or more and 10 mm or less.

3. The electrode composite according to claim 1 or 2, wherein an electrolyte is provided between the electrode and the ion-conducting membrane.

4. The electrode composite according to claim 1, wherein the electrode is sealed with only the ion-conducting membrane, or with only the ion-conducting membrane and an adhesive material.

5. The electrode composite according to claim 1 or 2, wherein the electrode is made of metallic Li.

6. The 1M LiPF of the ion-conducting film ６ PC (lithium hexafluoride phosphate) electrolyte permeation rate is 0 mg / cm² ２ / day or more 0.1mg / cm ２ The electrode composite according to claim 1 or 2, wherein the number of days is less than or equal to / day.

7. The electrode composite according to claim 1 or 2, wherein the maximum free volume radius of the ion-conducting membrane is 0.15 nm or more and 0.38 nm or less.

8. The electrode composite according to claim 1 or 2, having an inorganic solid electrolyte layer.

9. A battery comprising an electrode composite according to claim 1 and a counter electrode of the electrode composite.

10. The battery according to claim 9, wherein the electrode composite and the counter electrode are sealed in a bag-like manner with an outer material.

11. A battery according to claim 9 or claim 10, comprising an electrolyte.

12. The battery according to claim 11, having two or more types of electrolytes, each with a different composition.

13. The battery according to claim 12, wherein the electrode complex has an electrolyte (electrolyte A) between the ion-conducting membrane and the electrode, and has an electrolyte (electrolyte B) with a different composition from electrolyte A between the electrode complex and the counter electrode.

14. A vehicle, unmanned transport aircraft, flying object, electronic equipment, or stationary power source comprising the battery described in claim 9.

15. Porosity is 0% or more and 10% or less, 1M LiPF ６ PC (lithium hexafluoride phosphate) electrolyte permeation rate is 0 mg / cm² ２ / day or more 0.1mg / cm ２ Ion-conducting membranes with a frequency of less than / day.

16. The ion-conducting membrane according to claim 15, wherein the maximum free volume radius of the ion-conducting membrane is 0.15 nm or more and 0.38 nm or less.

17. The ion-conducting membrane according to claim 15, having an inorganic solid electrolyte layer.

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