Manufacturing method for electrode for electrochemical device, electrode for electrochemical device, electrochemical device, electrical equipment, and mobile body

Abstract

To provide a method that is capable of manufacturing an electrode for an electrochemical device with excellent battery characteristics.SOLUTION: A manufacturing method for an electrode for an electrochemical device includes a substrate, an electrode composite layer containing an active material on the substrate, and a solid electrolyte layer containing a solid electrolyte on the electrode composite layer. The electrode composite layer has an uneven structure. The method includes the step in which the solid electrolyte layer is formed by applying a liquid composition for forming the solid electrolyte layer including the solid electrolyte and a dispersion medium onto the electrode composite layer using an inkjet method such that the amount applied per coating is 0.34 mg / cm2 or more and 10 mg / cm2 or less, thereby forming the solid electrolyte layer. The viscosity of the liquid composition for forming the solid electrolyte layer is 4 mPa s or more and 20 mPa s or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing an electrode for an electrochemical device, an electrode for an electrochemical device, an electrochemical device, an electric device, and a mobile object. [Background technology]

[0002] Electrochemical elements such as lithium-ion secondary batteries, lithium-ion capacitors, electric double-layer capacitors, and redox capacitors are widely used in electronic devices, electric vehicles, and other devices. Demand for in-vehicle electrochemical elements is expected to grow, driven in part by the need for low environmental impact. This demand has led to demand for further improvements in the safety and energy density of electrochemical elements, and active efforts are underway to commercialize electrochemical elements that use solid electrolytes instead of conventional liquid electrolytes. As a method for manufacturing an electrode used in an electrochemical element, there is a method in which a solid electrolyte layer is applied onto an electrode mixture layer having an uneven shape by using a spin coating method (see, for example, Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0003] An embodiment of the present invention provides a method for producing an electrode for an electrochemical device, which can produce an electrode for an electrochemical device having excellent battery characteristics. [Means for solving the problem]

[0004] In order to solve the above problems, a method for producing an electrode for an electrochemical element according to one embodiment of the present invention comprises the steps of: A method for manufacturing an electrode for an electrochemical element, the method comprising: a substrate; an electrode mixture layer containing an active material on the substrate; and a solid electrolyte layer containing a solid electrolyte on the electrode mixture layer, the method comprising: the electrode mixture layer has an uneven structure, A liquid composition for forming a solid electrolyte layer containing the solid electrolyte and a dispersion medium was applied onto the electrode mixture layer by an inkjet method in an amount of 0.34 mg / cm 2 in one application.2 More than 10mg / cm 2 forming the solid electrolyte layer by applying the following: The viscosity of the solid electrolyte layer-forming liquid composition is 4 mPa·s or more and 20 mPa·s or less. [Effects of the Invention]

[0005] According to one embodiment of the present invention, it is possible to provide a method for producing an electrode for an electrochemical device, which can produce an electrode for an electrochemical device having excellent battery characteristics. [Brief explanation of the drawings]

[0006] [Figure 1A] FIG. 1A is a schematic cross-sectional view showing an electrode stack according to one embodiment of the present invention. [Figure 1B] FIG. 1B is a schematic cross-sectional view showing an electrode stack according to another embodiment of the present invention. [Figure 1C] FIG. 1C is a schematic cross-sectional view showing an electrode stack according to still another embodiment of the present invention. [Figure 2A] FIG. 2A is a schematic cross-sectional view showing an electrode stack according to one embodiment of the present invention. [Figure 2B] FIG. 2B is a schematic cross-sectional view showing an electrode stack according to one embodiment of the present invention. [Figure 3] FIG. 3 is a schematic top view showing an electrode for an electrochemical device according to one embodiment of the present invention. [Figure 4] FIG. 4 is a schematic top view showing an electrode for an electrochemical device according to another embodiment of the present invention. [Figure 5] FIG. 5 is a schematic top view showing an electrode for an electrochemical device according to still another embodiment of the present invention. [Figure 6A] FIG. 6A is a schematic cross-sectional view (part 1) showing the positional relationship between an insulating resin layer and an electrode mixture layer in an electrode for electrochemical elements according to one embodiment of the present invention. [Figure 6B]FIG. 6B is a schematic cross-sectional view (part 2) showing the positional relationship between the insulating resin layer and the electrode mixture layer in the electrode for electrochemical elements according to one embodiment of the present invention. [Figure 6C] FIG. 6C is a schematic cross-sectional view (part 3) showing the positional relationship between an insulating resin layer and an electrode mixture layer in an electrode for electrochemical elements according to one embodiment of the present invention. [Figure 6D] FIG. 6D is a schematic cross-sectional view (part 4) showing the positional relationship between an insulating resin layer and an electrode mixture layer in an electrode for electrochemical elements according to one embodiment of the present invention. [Figure 7] FIG. 7 is a schematic top view showing the positional relationship between an insulating resin layer and an electrode mixture layer in an electrode for electrochemical elements according to one embodiment of the present invention. [Figure 8A] FIG. 8A is a schematic cross-sectional view (part 1) showing the relationship between the average thickness of an insulating resin layer and an electrode mixture layer in an electrode for electrochemical elements according to one embodiment of the present invention. [Figure 8B] FIG. 8B is a schematic cross-sectional view (part 2) showing the relationship between the average thickness of the insulating resin layer and the average thickness of the electrode mixture layer in the electrode for electrochemical elements according to one embodiment of the present invention. [Figure 8C] FIG. 8C is a schematic cross-sectional view (part 3) showing the relationship between the average thickness of an insulating resin layer and an average thickness of an electrode mixture layer in an electrode for electrochemical elements according to one embodiment of the present invention. [Figure 9] FIG. 9 is a schematic diagram showing an example of an insulating resin layer manufacturing apparatus (liquid ejection apparatus) for carrying out a method for manufacturing an electrode laminate according to one embodiment of the present invention. [Figure 10] FIG. 10 is a schematic diagram showing another example of an insulating resin layer manufacturing apparatus (liquid ejection apparatus) for carrying out the method for manufacturing an electrode laminate according to one embodiment of the present invention. [Figure 11] FIG. 11 is a schematic diagram (part 1) illustrating a method for producing an electrode for an electrochemical device according to one embodiment of the present invention. [Figure 12] FIG. 12 is a schematic diagram showing yet another example of an insulating resin layer manufacturing apparatus (liquid ejection apparatus) for carrying out a method for manufacturing an electrode laminate according to one embodiment of the present invention. [Figure 13] FIG. 13 is a configuration diagram (part 1) showing an example of a printing unit employing an inkjet system and a transfer system as a liquid composition applying means in an insulating resin layer manufacturing apparatus according to one embodiment of the present invention. [Figure 14] FIG. 14 is a configuration diagram (part 2) showing an example of a printing unit employing an inkjet system and a transfer system as a liquid composition applying means in an insulating resin layer manufacturing apparatus according to one embodiment of the present invention. [Figure 15] FIG. 15 is a schematic cross-sectional view showing an electrochemical device according to one embodiment of the present invention. [Figure 16] FIG. 16 is a schematic cross-sectional view showing an example of an all-solid-state battery, which is an electrochemical element according to one embodiment of the present invention. [Figure 17] FIG. 17 is a schematic diagram showing an example of a moving body that is an electrochemical device according to one embodiment of the present invention. [Figure 18] FIG. 18 is a schematic diagram of a binarized SEM photograph of an electrode mixture layer according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0007] A method for manufacturing an electrode for an electrochemical element according to one embodiment of the present invention is a method for manufacturing an electrode for an electrochemical element having a substrate, an electrode mixture layer containing an active material on the substrate, and a solid electrolyte layer containing a solid electrolyte on the electrode mixture layer, the electrode mixture layer has an uneven structure, A liquid composition for forming a solid electrolyte layer containing the solid electrolyte and a dispersion medium was applied onto the electrode mixture layer by an inkjet method in an amount of 0.34 mg / cm 2 in one application. 2 More than 10mg / cm 2 forming the solid electrolyte layer by applying the following: The viscosity of the liquid composition for forming a solid electrolyte layer is 4 mPa·s or more and 20 mPa·s or less. With this configuration, an electrode for an electrochemical device having excellent battery characteristics can be produced.

[0008] It has been known that battery characteristics can be improved by forming a solid electrolyte layer on an electrode mixture layer having an uneven surface rather than on a flat electrode layer, thereby increasing the surface area between the electrode mixture layer and the solid electrolyte layer. In the method described in Patent Document 1, the solid electrolyte layer is applied to the electrode mixture layer having an uneven surface using a spin coating method, but this method has the problem that the liquid composition remains in the recesses of the electrode mixture layer, making it difficult to form a solid electrolyte layer with a uniform thickness, and short circuits occur in the protrusions where the thickness is thin. Furthermore, even when a solid electrolyte layer is formed on an electrode mixture layer having an uneven shape using an inkjet method, if the amount of coating applied in one application is not appropriate, the liquid composition flows into the recesses of the electrode mixture layer, making it difficult to form a uniform film as described above, and causing a short circuit.

[0009] In one embodiment of the present invention, a method for producing an electrode for an electrochemical element includes applying a liquid composition containing the solid electrolyte and a dispersion medium onto the electrode mixture layer by an inkjet method in an amount of 0.34 mg / cm 2 at a time. 2 More than 10mg / cm 2 By forming the solid electrolyte layer by coating as described below, a solid electrolyte layer with a uniform thickness can be formed, and therefore the produced electrode for electrochemical devices does not cause short circuits and has excellent battery characteristics such as input / output characteristics.

[0010] (Method for manufacturing electrodes for electrochemical elements and apparatus for manufacturing electrodes for electrochemical elements) The method for manufacturing an electrode for an electrochemical element according to one embodiment of the present invention includes a solid electrolyte layer forming step, and preferably includes an electrode mixture layer forming step and an insulating layer forming step, and may include other steps as necessary. The manufacturing apparatus for an electrode for an electrochemical element according to one embodiment of the present invention preferably includes a solid electrolyte layer forming means, an electrode mixture layer forming means, and an insulating layer forming step, and may include other means as necessary. The method for manufacturing an electrode for an electrochemical element can be suitably carried out by an apparatus for manufacturing an electrode for an electrochemical element, the solid electrolyte layer forming step can be suitably carried out by a solid electrolyte layer forming means, the electrode mixture layer forming step can be suitably carried out by an electrode mixture layer forming means, the insulating layer forming step can be suitably carried out by an insulating layer forming means, and the other steps can be suitably carried out by other means.

[0011] <Solid Electrolyte Layer Forming Step and Solid Electrolyte Layer Forming Means> In the solid electrolyte layer forming step, a liquid composition for forming a solid electrolyte layer containing the solid electrolyte and a dispersion medium is applied in an amount of 0.34 mg / cm 2 by an ink jet method. 2 More than 10mg / cm 2 This is a step of forming the solid electrolyte layer by applying the following: The ink-jet method can be carried out using a liquid ejection device. The amount of application per one pass refers to the weight per unit area of ​​the liquid composition for forming a solid electrolyte layer that is ejected during one movement of the inkjet head. Specifically, the liquid composition for forming a solid electrolyte layer that has been applied to an electrode (substrate and electrode mixture layer) is punched out into 10 circular pieces with a radius of 1 cm, and the total weight and the weight of the electrodes are measured using a balance (manufacturer's name), and the value is calculated by subtracting the weight of the electrodes from the total weight.

[0012] In addition, the solid electrolyte layer forming step involves applying a liquid composition for forming a solid electrolyte layer, containing a solid electrolyte and a dispersion medium, onto the electrode mixture layer by an inkjet method in an amount of 0.34 mg / cm 2 per application. 2 More than 10mg / cm 2 It is also possible to form a solid electrolyte laminate having two or more solid electrolyte layers by repeatedly applying the coating as follows. In the solid electrolyte layer forming step, another solid electrolyte layer can also be formed by applying a liquid composition for forming a solid electrolyte layer that contains another solid electrolyte different from the solid electrolyte.

[0013] The liquid ejection device includes a storage container and an ejection means that ejects the solid electrolyte layer forming liquid composition stored in the storage container using an inkjet head, and may further include other components as necessary.

[0014] <<Liquid composition for forming solid electrolyte layer>> The liquid composition for forming a solid electrolyte layer contains a solid electrolyte and a dispersion medium, and may contain an active material, a binder, a dispersant, a conductive aid, other components, and the like, as needed.

[0015] -Solid electrolyte- The solid electrolyte is not particularly limited and can be appropriately selected depending on the purpose as long as it exhibits electronic insulation and ion conductivity and does not react with the dispersion medium, and examples thereof include oxide solid electrolytes, sulfide solid electrolytes, etc. Among these, sulfide solid electrolytes are preferred from the viewpoint of having high plasticity, thereby forming good interfaces between solid electrolyte particles or between the solid electrolyte and the active material, and suppressing deterioration of ion conductivity, and crystalline argyrodite-type sulfide solid electrolytes are more preferred from the viewpoint of obtaining an excellent dispersion effect similar to that of the active material.

[0016] Examples of oxide solid electrolytes include compounds that contain oxygen atoms, have the ionic conductivity of a metal belonging to Group 1 or 2 of the periodic table, and have electronic insulation properties. In this specification, "having electronic insulation properties" means that when a positive electrode and a negative electrode are placed opposite each other with a solid electrolyte layer interposed therebetween, no short circuit occurs. In this specification, "exhibiting ion conductivity" means that when a positive electrode and a negative electrode are placed opposite each other with a solid electrolyte layer interposed therebetween, only ions move when a potential difference is applied.

[0017] Specific examples of oxide solid electrolytes include Li xa La ya TiO3 [xa=0.3~0.7, ya=0.3~0.7] (LLT), Li xb La yb Zr zb Mbb mb Onb (Mbb is at least one element selected from Al, Mg, Ca, Sr, V, Nb, Ta, Ti, Ge, In, and Sn, xb satisfies 5≦xb≦10, yb satisfies 1≦yb≦4, zb satisfies 1≦zb≦4, mb satisfies 0≦mb≦2, and nb satisfies 5≦nb≦20), Li xc B yc Mcc zc O nc (Mcc is at least one element selected from C, S, Al, Si, Ga, Ge, In, and Sn, xc satisfies 0≦xc≦5, yc satisfies 0≦yc≦1, zc satisfies 0≦zc≦1, and nc satisfies 0≦nc≦6), Li xd (Al,Ga) yd (Ti,Ge) zd Si ad P md O nd (where 1≦xd≦3, 0≦yd≦1, 0≦zd≦2, 0≦ad≦1, 1≦md≦7, 3≦nd≦13), Li(3-2xe)Mee xe DeeO (where xe represents a number of 0 or more and 0.1 or less, Mee represents a divalent metal atom, and Dee represents a halogen atom or a combination of two or more halogen atoms), Li xf Si yf O zf (1≦xf≦5, 0 <yf≦3、1≦zf≦10)、Li xg S yg O zg (1≦xg≦3, 0 <yg≦2、1≦zg≦10)、Li3BO3-Li2SO4、Li2O-B2O3-P2O5、Li2O-SiO2、Li6BaLa2Ta2O 12 , LiPO (4-3 / 2w) Nw (w<1), Li with LISICON (Lithium super ionic conductor) type crystal structure 3.5 Zn 0.25 GeO4, La with perovskite crystal structure 0.55 Li 0.35 TiO3, LiTi2P3O with NASICON (sodium super ionic conductor) type crystal structure 12 , Li 1+xh+yh (Al,Ga)xh(Ti,Ge)2-xh Si yh P 3-yh O 12 (where 0≦xh≦1, 0≦yh≦1), Li7La3Zr2O with a garnet-type crystal structure 12 (LLZ) and others.

[0018] As the oxide solid electrolyte, a phosphorus compound containing Li, P, and O is also desirable. Examples include lithium phosphate (Li3PO4), LiPON in which some of the oxygen in lithium phosphate is substituted with nitrogen, and LiPOD1 (D1 is at least one selected from Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb, Mo, Ru, Ag, Ta, W, Pt, Au, etc.). LiAlON (Al is at least one selected from Si, B, Ge, Al, C, Ga, etc.) can also be preferably used.

[0019] Sulfide solid electrolytes can be broadly divided into, for example, crystalline sulfide solid electrolytes and glass-based solid electrolytes.

[0020] Examples of crystalline sulfide solid electrolytes include Li 9.54 Si 1.74 P 1.44 S 11.7 Cl 0.3 , Li 9.6 P3S 12 , Li9P3S9O3, Li 9.81 Sn 0.81 P 2.19 S 12 , Li 9.42 Si 1.02 P 2.1 S 9.96 O 2.04 , Li 10 Ge(P 1-x Sb x )2S 12 (0≦x≦0.15), Li 10 SnP2S 12 , Li 10.35 [M1 1-x M2 x ] 1.35 P 1.65 S 12(M1, M2 = Si, Ge, Sn, As, Sb, 0≦x≦0.15), Li 11 Si2PS 12 , Li 11 AlP2S 12 , Li 3.45 Si 0.45 P 0.55 S4, Li6PS5X(X=Cl,Br,I), Li5PS4X2(X=Cl,Br,I), Li 5.5 PS 4.5 Cl 1.5 , Li 5.35 Ca 0.1 PS 4.5 Cl 1.55 , Li 6+x M x Sb 1-x S5I(M=Si,Ge,Sn, 0≦x≦1), Li7P2S8I, γ-Li3PS4, Li4MS4(M=Ge,Sn,As), Li 4-x Sn 1-x SbxS4(0≦x≦0.15), Li 4-x Ge 1-x PxS4(0≦x≦0.15), Li 3+5x P 1-x Examples include S4 (0≦x≦0.3).

[0021] Examples of glass-based sulfide solid electrolytes include Li2S-P2S5, Li2S-P2S5-LiI, Li2S-P2S5-P2O5, Li2S-P2S5-LiCl, Li2S-SiS2, Li2S-SiS2-P2S5, Li2S-SiS2-Al2S3, and Li2S-SiS2-Li x MO y (M=Si, P, Ge), etc. In addition, Li7P3S, in which part of the glass-based sulfide solid electrolyte is crystallized, 11 Glass ceramics, etc. may also be used. Here, the mixing ratio of the raw materials for the glass-based sulfide solid electrolyte is not limited.

[0022] The content of the solid electrolyte is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10% by mass or more and 50% by mass or less relative to the total amount of the liquid composition for forming a solid electrolyte layer. The content is expressed as solid content.

[0023] -Dispersion medium- The dispersion medium is not particularly limited and can be appropriately selected depending on the purpose. Examples include aqueous dispersion media such as water, ethylene glycol, and propylene glycol; amide-based dispersion media such as N-methyl-2-pyrrolidone, 2-pyrrolidone, and N,N-dimethylacetamide; ketone-based dispersion media such as cyclohexanone; ester-based dispersion media such as butyl acetate; aromatic dispersion media such as mesitylene; and alcohol-based dispersion media such as 2-n-butoxymethanol and 2-dimethylethanol. When a positive electrode active material is contained as the active material, an amide-based dispersion medium, an ester-based dispersion medium, or a ketone-based dispersion medium is preferred from the viewpoint of obtaining excellent dispersibility. When a sulfide solid electrolyte is contained as another component, an ester-based compound is preferred, and it is more preferred that the alkyl group is selected from a linear alkyl group and a branched alkyl group having 3 or more carbon atoms on the carbonyl group carbon side, and that the alkyl group on the oxygen side of the carbonyl group is a methyl group or an ethyl group. These may be used alone or in combination of two or more.

[0024] The dispersion medium preferably has a boiling point under normal pressure conditions. The boiling point of the dispersion medium is not particularly limited and can be appropriately selected depending on the purpose, but from the viewpoints of storage stability and handleability, it is preferably 100° C. or higher, more preferably 120° C. or higher, and even more preferably 150° C. or higher. From the viewpoint of quick drying in the drying step, it is preferably 300° C. or lower, more preferably 250° C. or lower, and even more preferably 200° C. or lower.

[0025] When a positive electrode active material is used as the active material, the water content of the dispersion medium is preferably 2,000 ppm or less, and more preferably 1,000 ppm or less. When a sulfide solid electrolyte is contained as another component, the water content of the dispersion medium is preferably 100 ppm or less, and more preferably 50 ppm or less. The method for measuring the water content of the dispersion medium is not particularly limited and can be selected appropriately depending on the purpose, and can be, for example, measured by Karl Fischer water content measurement using coulometric titration with water vaporization at 25° C. The measuring device is not particularly limited and can be selected appropriately depending on the purpose, and examples thereof include a Karl Fischer trace water content analyzer (CA-200, manufactured by Nitto Seiko Analytech Co., Ltd.).

[0026] The content of the dispersion medium is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 40% by mass or more and 95% by mass or less relative to the total amount of the liquid composition for forming a solid electrolyte layer, and more preferably 40% by mass or more and 80% by mass or less in terms of suppressing the formation of coffee rings during heating and drying.

[0027] -Active material- The active material may be a positive electrode active material or a negative electrode active material. The positive electrode active material or the negative electrode active material may be used alone or in combination of two or more.

[0028] -Cathode active material- The positive electrode active material is not particularly limited and can be appropriately selected depending on the purpose as long as it is a material that can reversibly absorb and release alkali metal ions, and examples thereof include alkali metal-containing transition metal compounds. Examples of alkali metal-containing transition metal compounds include lithium-containing transition metal compounds such as composite oxides containing lithium and one or more elements selected from the group consisting of cobalt, manganese, nickel, chromium, iron, and vanadium. Examples of lithium-containing transition metal compounds include lithium cobalt oxide, lithium nickel oxide, and lithium manganese oxide.

[0029] As the alkali metal-containing transition metal compound, a polyanion compound having an XO4 tetrahedron (X=P, S, As, Mo, W, Si, etc.) in the crystal structure can be used. Among these, lithium-containing transition metal phosphate compounds such as lithium phosphate and lithium vanadium phosphate are preferred from the viewpoint of cycle characteristics, and lithium vanadium phosphate is preferred from the viewpoint of lithium diffusion coefficient and output characteristics. When a polyanion compound is used, it is preferable that the surface of the polyanion compound is coated with a conductive aid such as a carbon material to form a composite, in terms of electron conductivity.

[0030] The alkali metal-containing transition metal compound preferably has at least a portion of its surface coated with an ion-conductive oxide, preferably a lithium ion-conductive oxide. The lithium ion conductive oxide is not particularly limited and can be appropriately selected depending on the purpose. For example, x AO y (A is B, C, Al, Si, P, S, Ti, Zr, Nb, Mo, Ta, Sc, V, Y, Ca, Sr, Ba, Hf, Ta, Cr, or W, and x and y are positive numbers.) Specific examples of lithium ion conductive oxides include Li3BO3, LiBO2, Li2CO3, LiAlO2, Li4SiO4, Li2SiO3, Li3PO4, Li2SO4, Li2TiO3, and Li4Ti5O. 12 , Li2Ti2O5, Li2ZrO3, LiNbO3, LiTaO3, Li2MoO4, and Li2WO4. Among these, Li4Ti5O 12 , Li2ZrO3, or LiNbO3 are preferred. The lithium ion conductive oxide may be a composite oxide, which may be any combination of lithium ion conductive oxides, such as Li4SiO4-Li3BO3 and Li4SiO4-Li3PO4.

[0031] -Negative electrode active material- The negative electrode active material is not particularly limited as long as it is a material that can reversibly absorb and release alkali metal ions and can be appropriately selected depending on the purpose. For example, a carbon material containing graphite having a graphite-type crystal structure can be used. Examples of carbon materials include natural graphite, spherical or fibrous artificial graphite, non-graphitizable carbon (hard carbon), and easily graphitizable carbon (soft carbon). Examples of materials other than carbon materials include lithium titanate and titanium oxide. From the viewpoint of increasing the energy density of a lithium ion secondary battery, high capacity materials such as silicon, tin, silicon alloys, tin alloys, silicon oxide, silicon nitride, and tin oxide can also be suitably used as the negative electrode active material.

[0032] The mode diameter of the active material is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.5 μm or more and 20 μm or less, and more preferably 3 μm or more and 10 μm or less. When the mode diameter of the active material is 0.5 μm or more and 20 μm or less, ejection defects are less likely to occur when the electrode mixture layer-forming liquid composition is ejected by a liquid ejection means. Furthermore, when the mode diameter of the active material is 3 μm or more and 10 μm or less, an electrode with better battery characteristics can be obtained. In this specification, the diameter at the maximum value of the particle size distribution of the active material in the liquid composition for forming an electrode mixture layer was calculated as the mode diameter.

[0033] The method for measuring the mode diameter of the active material is not particularly limited and can be appropriately selected depending on the purpose. For example, the measurement can be performed in accordance with ISO 13320:2009. The device used for the measurement is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a laser diffraction particle size distribution measuring device (Mastersizer 3000, manufactured by Malvern Instruments).

[0034] The maximum particle size Dmax of the active material is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 40 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less. When the maximum particle diameter Dmax of the active material is 40 μm or less, ejection defects are less likely to occur when the electrode mixture layer forming liquid composition is ejected by a liquid ejection means.

[0035] The method for measuring the maximum particle diameter Dmax of the active material is not particularly limited and can be appropriately selected depending on the purpose. For example, the measurement can be performed in accordance with ISO 13320:2009. The device used for the measurement is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a laser diffraction particle size distribution measuring device (Mastersizer 3000, manufactured by Malvern Instruments).

[0036] The median diameter D50 of the active material is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 15 μm or less, more preferably 10 μm or less, and even more preferably 5 μm or less. When the median diameter D50 of the active material is 15 μm or less, the coating efficiency and battery characteristics are improved.

[0037] The method for measuring the median diameter D50 of the active material is not particularly limited and can be appropriately selected depending on the purpose. For example, the measurement can be performed in accordance with ISO 13320:2009. The device used for the measurement is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a laser diffraction particle size distribution measuring device (Mastersizer 3000, manufactured by Malvern Instruments).

[0038] -Binder- The binder is not particularly limited and can be appropriately selected depending on the purpose as long as it can bind negative electrode materials together, positive electrode materials together, a negative electrode material and a negative electrode substrate, or a positive electrode material and a positive electrode substrate. Note that, in order to use it for inkjet ejection, from the viewpoint of suppressing nozzle clogging of the liquid ejection head, it is preferable that the binder does not easily increase the viscosity of the solid electrolyte layer-forming liquid composition.

[0039] As the binder, a polymer compound can be used. Examples of polymer compounds include thermoplastic resins such as polyvinylidene fluoride (PVdF), acrylic resin, polyethylene, polypropylene, polyurethane, nylon, polytetrafluoroethylene, polyphenylene sulfide, polyethylene terephthalate, and polybutylene terephthalate, polyamide compounds, polyimide compounds, polyamideimide, ethylene-propylene-butadiene rubber (EPBR), styrene-butadiene rubber (SBR), nitrile butadiene rubber (NBR), isoprene rubber, polyisobutene, and polyethylene. Examples of such polymers include polyethylene glycol (PEO), polymethyl methacrylate (PMMA), polyethyl methacrylate (PEMA), polybutyl methacrylate (PBMA), polyethylene vinyl acetate (PEVA), poly2-(dimethylamino)ethyl methacrylate, poly2-(diethylamino)ethyl methacrylate, poly(2-(dimethylamino)ethyl methacrylate-polybutyl methacrylate) copolymer, poly(2-(diethylamino)ethyl methacrylate-polybutyl methacrylate) copolymer, and carboxymethyl cellulose.

[0040] The content of the binder relative to the active material is not particularly limited and can be set appropriately depending on the purpose, but is preferably 0.5% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass or less, and even more preferably 1.5% by mass or more and 5% by mass or less.

[0041] -Dispersant- The dispersant is not particularly limited and can be appropriately selected depending on the purpose as long as it is capable of improving the dispersibility of the active material. Examples include polymer dispersants such as carboxymethyl cellulose, polyethylene, polyethylene oxide, polypropylene oxide, polycarboxylic acid, naphthalene sulfonic acid formalin condensation, polyethylene glycol, polycarboxylic acid partial alkyl ester, polyether, and polyalkylene polyamine; low molecular weight dispersants such as alkyl sulfonic acid, quaternary ammonium, higher alcohol alkylene oxide, polyhydric alcohol ester, and alkyl polyamine; and inorganic dispersants such as polyphosphate dispersants.

[0042] -Conductive additive- The conductive additive is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include carbon black produced by a furnace method, an acetylene method, a gasification method, etc., and carbon materials such as carbon nanofibers, carbon nanotubes, graphene, and graphite particles. Examples of the conductive additive other than the carbon material include metal particles such as aluminum, metal fibers, etc. The conductive additive may be previously compounded with the active material.

[0043] The content of the conductive additive relative to the active material is not particularly limited and can be set appropriately depending on the purpose, but is preferably 10% by mass or less, and more preferably 8% by mass or less. A content of the conductive additive relative to the active material of 10% by mass or less is preferable because the stability of the liquid composition for forming an electrode mixture layer is improved, and a content of the conductive additive relative to the active material of 8% by mass or less is preferable because the stability of the liquid composition for forming a solid electrolyte layer is further improved.

[0044] -Other ingredients- The other components are not particularly limited and can be selected appropriately depending on the purpose. Examples include surfactants, pH adjusters, rust inhibitors, preservatives, antifungal agents, antioxidants, antireducing agents, evaporation promoters, chelating agents, thickeners, etc.

[0045] The viscosity of the solid electrolyte layer-forming liquid composition is a viscosity that allows it to be ejected from a liquid ejection head, and is 4 mPa·s to 20 mPa·s, preferably 4 mPa·s to 12 mPa·s, and more preferably 4 mPa·s to 8 mPa·s. A viscosity of 4 mPa·s or more can prevent the applied solid electrolyte layer-forming liquid composition from flowing into the recesses of the electrode mixture layer, and can also prevent uneven drying. Therefore, unevenness in the film thickness and composition upon drying can be reduced. Furthermore, a viscosity of 20 mPa·s or less allows the solid electrolyte layer-forming liquid composition to easily penetrate into the voids of the electrode mixture layer, thereby preventing the applied solid electrolyte layer-forming liquid composition from flowing into the recesses of the electrode mixture layer. The method for measuring viscosity is not particularly limited and can be appropriately selected depending on the purpose. For example, viscosity can be measured using a viscometer (DV2T, manufactured by Brookfield) at a rotation speed of 50 rpm at room temperature (25°C).

[0046] <Electrode mixture layer forming step and electrode mixture layer forming means> The electrode mixture layer forming step is a step of forming an electrode mixture layer on a substrate. The electrode mixture layer forming means is a means for forming an electrode mixture layer on a substrate. The electrode mixture layer forming step and the electrode mixture layer forming means are not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a method in which a dispersion obtained by dispersing a powdered active material, a binder, a conductive material, etc. in a liquid is applied to a substrate, and the substrate is fixed and dried. In this case, coating methods such as an inkjet method, a spray, a dispenser, a die coater, and lift-up coating can be suitably used.

[0047] <<Liquid composition for forming electrode composite layer>> The electrode mixture layer-forming liquid composition contains a solid electrolyte and a dispersion medium, and may contain, as necessary, an active material, a binder, a dispersant, a conductive additive, other components, etc. The active material, binder, dispersant, conductive additive, and other components may be the same as those contained in the solid electrolyte layer-forming liquid composition.

[0048] <Insulating layer forming step and insulating layer forming means> The insulating layer forming step is a step of forming an insulating layer on a substrate, and preferably includes a liquid composition applying step and a liquid composition curing step. The insulating layer forming means is a means for forming an insulating layer on a substrate, and preferably includes a liquid composition applying means and a liquid composition curing means. The insulating layer forming step can be suitably carried out by an insulating layer forming means, the liquid composition applying step can be suitably carried out by a liquid composition applying means, and the liquid composition curing step can be suitably carried out by a liquid composition curing means.

[0049] <<Liquid composition application step and liquid composition application means>> The liquid composition application step is a step of applying the liquid composition onto a substrate. The liquid composition applying means is a means for applying the liquid composition onto a substrate. The liquid composition application step and the liquid composition application means are not particularly limited and can be appropriately selected depending on the purpose, and any printing device can be used according to various printing methods, such as spin coating, casting, microgravure coating, gravure coating, bar coating, roll coating, wire bar coating, dip coating, slit coating, capillary coating, spray coating, nozzle coating, gravure printing, screen printing, flexographic printing, offset printing, reverse printing, inkjet printing, etc. Among these, inkjet printing is preferred from the viewpoint of being able to form an insulating layer with high precision.

[0050] <<Liquid composition curing step and liquid composition curing means>> The liquid composition curing step is a step of curing the liquid composition by applying heat or light to the liquid composition. The liquid composition curing means is a means for curing the liquid composition by applying heat or light to the liquid composition. By applying heat or light to the liquid composition, the polymerizable compound in the liquid composition is polymerized and polymerization-induced phase separation occurs, thereby obtaining an insulating layer having a porous structure.

[0051] The light used in the liquid composition curing step and the liquid composition curing means is preferably active energy rays. The active energy rays may be any rays capable of imparting the energy necessary to promote the polymerization reaction of the polymerizable compound in the liquid composition, and are not particularly limited. Examples include ultraviolet rays, electron beams, α rays, β rays, γ rays, and X-rays. Among these, ultraviolet rays are preferred. In particular, when a high-energy light source is used, the polymerization reaction can be promoted without using a polymerization initiator.

[0052] The irradiation intensity of the active energy rays is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 1 W / cm 2 Preferably, it is 300 mW / cm or less. 2 More preferably, it is 100 mW / cm or less. 2 It is even more preferable that: If the irradiation intensity of the active energy rays is too low, polymerization-induced phase separation will proceed excessively, which will cause variations in the porous structure and coarsening. In addition, the irradiation time will be long, which will reduce productivity. Therefore, it is recommended to use an irradiation intensity of 10 mW / cm 2 It is preferable that the power is 30 mW / cm or more. 2 More preferably, it is equal to or greater than this.

[0053] <Other processes and other means> Other steps in the method for producing an electrode for an electrochemical device are not particularly limited and can be appropriately selected depending on the purpose, as long as they do not impair the effects of the present invention. For example, a solvent removal step can be mentioned. Other means in the apparatus for producing an electrode for an electrochemical device are not particularly limited and can be appropriately selected depending on the purpose, as long as the effects of the present invention are not impaired. For example, solvent removal means may be used.

[0054] <<Solvent Removal Step and Solvent Removal Means>> The solvent removal step is a step of removing the solvent from the insulating layer. The solvent removal means is a means for removing the solvent from the insulating layer. The solvent removal step and the solvent removal means are not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a method of removing the solvent from the insulating layer by heating. In this case, heating under reduced pressure is preferred because it promotes solvent removal and can reduce the amount of solvent remaining in the insulating layer. Heating may be performed using a stage, or using a heating mechanism other than a stage. The heating mechanism may be installed either above or below the substrate, or multiple heating mechanisms may be installed. There are no particular limitations on the heating mechanism, and examples include a resistance heater, an infrared heater, and a fan heater. There are no particular limitations on the heating temperature, but from the viewpoint of energy use, a temperature of 70°C to 150°C is preferred. In the method for producing an electrode for electrochemical devices, the order of the insulating layer forming step and the electrode mixture layer forming step is not particularly limited. That is, the electrode mixture layer forming step may be performed before the insulating layer forming step, and after the electrode mixture layer is formed, the insulating layer may be formed on the outer periphery of the electrode mixture layer. In this case, the method for producing an electrode for electrochemical devices is performed in the order of the electrode mixture layer forming step, the insulating layer forming step, and the solvent removing step. Similarly, the electrode mixture layer forming step may be performed after the insulating layer forming step, and after the insulating layer is formed on the outer periphery of the substrate, the electrode mixture layer may be formed inside the insulating layer. In this case, the method for producing an electrode for an electrochemical device is performed in the order of the insulating layer forming step, the electrode mixture layer forming step, and the solvent removing step.

[0055] (Electrodes for electrochemical elements) The laminate for an all-solid-state electrochemical device of the present invention can be suitably applied to an electrode for an electrochemical device. The electrode for an electrochemical element comprises an electrode having a substrate and an electrode mixture layer containing an active material on the substrate, and a solid electrolyte layer on the electrode mixture layer, wherein the electrode mixture layer has convex portions of 5 μm or more, and the ratio (A / B) of the film thickness of the convex portions (A) to the film thickness of the concave portions (B) in the solid electrolyte is 0.8 or more and 1.2 or less. The substrate, solid electrolyte, and insulating layer are the same as those described above, and therefore redundant description will be omitted. In this specification, the negative electrode and the positive electrode may be referred to as "electrodes," the negative electrode substrate and the positive electrode substrate may be referred to as "substrates," and the negative electrode mixture layer and the positive electrode mixture layer may be referred to as "electrode mixture layers." Furthermore, when the first electrode is a negative electrode, the second electrode refers to a positive electrode, and when the first electrode is a positive electrode, the second electrode refers to a negative electrode.

[0056] Here, an embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments. In each drawing, the same components are denoted by the same reference numerals, and redundant explanations may be omitted. Furthermore, the number, position, shape, etc. of the components are not limited to the present embodiment, and the number, position, shape, etc. may be any number, position, shape, etc. that is preferable for implementing the present invention.

[0057] Fig. 1A is a schematic cross-sectional view showing an electrode laminate according to one embodiment of the present invention. Fig. 1B is a schematic cross-sectional view showing an electrode laminate according to another embodiment of the present invention. Fig. 1C is a schematic cross-sectional view showing an electrode laminate according to yet another embodiment of the present invention. An electrode laminate 35 has a first base 21, a first electrode mixture layer 20 disposed on the first base 21, an insulating layer 10 disposed on the outer periphery of the first electrode mixture layer 20, and a solid electrolyte layer 30 disposed on the first electrode mixture layer 20 and the insulating layer 10. 1A to 1C show a configuration in which the electrode mixture layer 20, the insulating layer 10, and the solid electrolyte layer 30 are provided on one side of the first substrate 21, but the electrode mixture layer 20, the insulating layer 10, and the solid electrolyte layer 30 may be provided on both opposing sides of the first substrate 21. As shown in FIG. 1B, an adhesive layer 22 containing a metal that alloys with lithium may be provided between the substrate 21 and the electrode mixture layer 20.

[0058] <Solid electrolyte layer> The solid electrolyte layer is not particularly limited and can be appropriately selected depending on the purpose. For example, it may contain an active material (negative electrode active material or positive electrode active material) and a sulfide solid electrolyte, and may further contain a conductive additive, a binder, a dispersant, and other components as necessary. The components contained in the solid electrolyte layer are the same as those described in the section <<Liquid composition for forming solid electrolyte layer>>, so duplicate descriptions will be omitted.

[0059] The average thickness of the solid electrolyte layer is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 2 μm or more and 40 μm or less. In addition, the ratio (A / B) of the thickness of the protrusions (A) to the thickness of the recesses (B) in the solid electrolyte is preferably 0.8 or more and 1.2 or less, thereby enabling the production of an electrode for an electrochemical device having excellent battery characteristics.

[0060] <Electrode composite layer> The electrode mixture layer (hereinafter sometimes referred to as "active material layer") is not particularly limited as long as it has an uneven structure and can be appropriately selected depending on the purpose. For example, it may contain an active material (negative electrode active material or positive electrode active material) and a sulfide solid electrolyte, and may further contain a conductive additive, a binder, a dispersant, and other components as necessary. From the viewpoint that the electrode for an electrochemical element or the electrode laminate has an insulating layer that can suppress a decrease in ion conductivity in the sulfide solid electrolyte-containing layer, the electrode mixture layer preferably contains an active material and a sulfide solid electrolyte.

[0061] The difference in surface roughness of the electrode mixture layer is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 μm or more, which increases the surface area of ​​the electrode mixture layer and the solid electrolyte layer and improves the battery characteristics. The difference in surface unevenness is the height X from the surface of the substrate 21 to the protrusion 20A of the electrode mixture layer 20, as shown in FIG. 2A. 1 and a height X from the surface of the substrate 21 to the recess 20B of the electrode mixture layer 20. 2 It means the difference between The difference in surface roughness can be measured from the surface profile using, for example, a laser microscope. In this embodiment, the protrusions and recesses of the electrode mixture layer are preferably formed alternately and repeatedly in a substantially periodic manner. In this specification, the protrusions and recesses of the uneven structure do not include protrusions and recesses formed on the surface of the active material layer by only one active material particle contained in the electrode mixture layer.

[0062] The porosity difference between the electrode mixture layers is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0% or more and 10% or less. This allows the speed at which the solid electrolyte layer-forming liquid composition permeates the electrode mixture layers to become uniform, thereby enabling the formation of a solid electrolyte layer with a uniform thickness. The porosity difference means the difference between the porosity of region 20C in the convex portion of electrode mixture layer 20, which has a radius of 50 μm and a film thickness of 2 μm to 40 μm, and the porosity of region 20D in the concave portion of electrode mixture layer 20, which has a radius of 50 μm and a film thickness of 2 μm to 40 μm, as shown in FIG. 2B.

[0063] The electrode mixture layer may have openings 23 as shown in FIG. 1C. The number of openings 23 is preferably one or more, and more preferably two or more. The openings 23 may penetrate the electrode mixture layer from the surface of the electrode mixture layer to the surface of the substrate, or may not penetrate all the way to the surface of the substrate. The opening 23 may be hollow or may be filled with the material 24. When the opening 23 is filled with the material 24, the material 24 may be a single type or a mixture of two or more types. In either case, the material 24 is different in quality (compound or composition) from the material constituting the electrode mixture layer. From the viewpoint of improving ion conductivity, the material 24 is preferably a material having the solid electrolyte contained in the sulfide solid electrolyte-containing layer, and more preferably a material having the same composition as the sulfide solid electrolyte contained in the sulfide solid electrolyte-containing layer. The electrode mixture layer having the openings 23 can be suitably produced by using inkjet as the electrode mixture layer forming means, since application control is easy.

[0064] <Insulating layer> The insulating layer in the electrode for electrochemical devices and electrode laminate according to the present invention is disposed on the outer periphery of the electrode mixture layer provided on the substrate, and may also be disposed on the substrate and on the outer periphery of the substrate.

[0065] Here, an embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments.

[0066] Fig. 3 is a schematic top view showing an electrode for an electrochemical device according to one embodiment of the present invention, Fig. 4 is a schematic top view showing an electrode for an electrochemical device according to another embodiment of the present invention, and Fig. 5 is a schematic top view showing an electrode for an electrochemical device according to yet another embodiment of the present invention.

[0067] In FIG. 3, insulating layer 10 is provided adjacent to two sides of the outer periphery of electrode mixture layer 20.

[0068] In FIG. 4, insulating layer 10 is provided adjacent to two long sides and two corners of the outer periphery of electrode mixture layer 20.

[0069] 5, insulating layer 10 is provided continuously adjacent to all four sides of the outer periphery of electrode mixture layer 20. Note that insulating layers may also be provided discontinuously adjacent to each other.

[0070] In this specification, "disposed on the outer periphery of the electrode mixture layer" means that the insulating layer may be disposed on at least two sides of the outer periphery of the electrode mixture layer, or may be disposed on three sides of the outer periphery of the electrode mixture layer, or may be disposed on all four sides of the outer periphery of the electrode mixture layer. In addition, the insulating layer may have a recess or a notch on any side to allow the electrode tab to protrude.

[0071] In this specification, "disposed on the outer periphery of the base" means that the insulating layer may be disposed so as to include the edge of the base, or may be disposed so that the base is exposed as shown in Figures 3 to 5.

[0072] Fig. 6A is a schematic cross-sectional view (part 1) showing the positional relationship between an insulating layer and an electrode mixture layer in an electrode for electrochemical devices according to one embodiment of the present invention. Fig. 6B is a schematic cross-sectional view (part 2) showing the positional relationship between an insulating layer and an electrode mixture layer in an electrode for electrochemical devices according to one embodiment of the present invention. Fig. 6C is a schematic cross-sectional view (part 3) showing the positional relationship between an insulating layer and an electrode mixture layer in an electrode for electrochemical devices according to one embodiment of the present invention. Fig. 6D is a schematic cross-sectional view (part 4) showing the positional relationship between an insulating layer and an electrode mixture layer in an electrode for electrochemical devices according to one embodiment of the present invention.

[0073] The insulating layer 10 may be separated from the electrode mixture layer 20 as shown in Fig. 6A, or may be in contact with the electrode mixture layer 20 as shown in Figs. 6B to 6D. Among these, it is preferable that the insulating layer 10 be in contact with the electrode mixture layer 20.

[0074] When the insulating layer 10 is in contact with the electrode mixture layer 20, the surfaces of the insulating layer 10 and the electrode mixture layer 20 may be in partial contact with each other as shown in Figure 6B, or the surfaces of the insulating layer 10 and the electrode mixture layer 20 may be in full contact with each other as shown in Figures 6C to 6D. Here, when the electrode mixture layer 20 is provided after the insulating layer 10 is formed, the electrode mixture layer 20 overlaps the insulating layer 10 side as shown in Fig. 6C. Similarly, when the insulating layer 10 is provided after the electrode mixture layer 10 is formed, the insulating layer 10 overlaps the electrode mixture layer 20 side as shown in Fig. 6D.

[0075] FIG. 7 is a schematic top view showing the positional relationship between an insulating layer and an electrode mixture layer in an electrode for electrochemical devices according to one embodiment of the present invention.

[0076] Here, when the insulating layer 10 and the electrode mixture layer 20 are spaced apart, the distance d between the insulating layer 10 and the electrode mixture layer 20 (the distance between the outer periphery of the electrode mixture layer 20 and the insulating layer) is defined as shown in Fig. 7. That is, when the insulating layer 10 and the electrode mixture layer 20 are adjacent to each other, d = 0, and the distance d between the electrode mixture layer and the insulating layer is the distance between the arrows shown in Fig. 7. Note that when the insulating layer overlaps the electrode mixture layer side, and when the electrode mixture layer overlaps the insulating layer side, as shown in Figs. 6C and 6D, a negative value is used.

[0077] The distance d between the insulating layer 10 and the electrode composite layer 20 (the distance between the outer periphery of the electrode composite layer 20 and the insulating layer) is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 10 mm or less, more preferably 5 mm or less, and even more preferably 1 mm or less. If the distance d between the insulating layer 10 and the electrode mixture layer 20 is 10 mm or less, the insulating layer and the electrode mixture layer are likely to come into contact with each other after the pressing step, which is preferable because the solid electrolyte layer can be uniformly formed on the insulating layer and the electrode mixture layer. This is also preferable because pressure can be applied uniformly to the solid electrolyte layer when the solid electrolyte layer is pressed.

[0078] FIG. 8A is a schematic cross-sectional view (part 1) showing the relationship between the average thickness of the insulating layer and the electrode composite layer in the electrode for an electrochemical element according to an embodiment of the present invention. FIG. 8B is a schematic cross-sectional view (part 2) showing the relationship between the average thickness of the insulating layer and the electrode composite layer in the electrode for an electrochemical element according to an embodiment of the present invention. FIG. 8C is a schematic cross-sectional view (part 3) showing the relationship between the average thickness of the insulating layer and the electrode composite layer in the electrode for an electrochemical element according to an embodiment of the present invention.

[0079] Regarding the relationship between the average thickness A of the electrode composite layer and the average thickness B of the insulating layer in the electrode laminate according to the present invention, there is no particular limitation and it can be appropriately selected according to the purpose. For example, as shown in FIGS. 8A to 8C, A < B, A = B, or A > B may be possible. Among these, it is preferable that A = B or A < B.

[0080] The average thickness of the insulating layer is not particularly limited and can be appropriately selected according to various conditions such as the average thickness of the electrode composite layer. However, it is preferably 1.0 μm or more and 150.0 μm or less, and more preferably 10.0 μm or more and 100.0 μm or less. When the average thickness of the insulating layer is 10.0 μm or more, the pressure load during pressing can be dispersed and a short circuit between the positive electrode and the negative electrode can be prevented, which is preferable. When the average thickness of the insulating layer is 100.0 μm or less, an electrochemical element with high density and excellent battery characteristics can be manufactured.

[0081] In the electrode laminate according to the present invention, the ratio (B / A) of the average thickness B of the insulating layer to the average thickness A of the electrode composite layer is not particularly limited and can be appropriately selected according to the purpose. However, it is preferably 0.97 or more and 1.03 or less, and more preferably 0.98 or more and 1.02 or less.

[0082] <O The method for measuring the average thickness A of the electrode composite layer and the average thickness B of the insulating layer is not particularly limited and can be appropriately selected according to the purpose. For example, it can be obtained by measuring the thickness at any three or more points and calculating the average value.

[0083] Since the insulating layer in the electrode laminate according to the present invention has a porous structure, the thickness of the electrode mixture layer and the thickness of the insulating layer can be easily and precisely controlled by pressing.

[0084] Furthermore, since the insulating layer can be formed by coating and polymerization-induced phase separation, the thickness can be easily controlled. An insulating layer having a bicontinuous structure can efficiently disperse the pressure generated during pressing, suppressing defects such as breakdown of the insulating layer and unevenness in height, thereby achieving a high-quality insulating layer.

[0085] The compression ratio of the insulating layer (after pressing at 500 MPa for 5 minutes) is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 1% to 50%, more preferably 5% to 20%.

[0086] When the compression ratio of the insulating layer is 50% or less, the strength of the insulating layer is improved, and the insulating layer can sufficiently maintain its shape when subjected to a pressing step.

[0087] When the compressibility of the insulating layer is 1% or more, the pressure applied from the insulating layer to the sulfide solid electrolyte-containing layer can be reduced in the pressing step after the formation of the sulfide solid electrolyte-containing layer.

[0088] The insulating layer can contain at least one of a resin and an inorganic oxide, and is preferable as an insulating resin layer containing a resin, since it can increase the energy density per unit weight of the battery and is lightweight, and a porous insulating resin layer is more preferable.

[0089] <Base> The substrate is not particularly limited as long as it has electron conductivity and is stable to the applied potential, and can be appropriately selected depending on the purpose. Examples include aluminum foil, copper foil, stainless steel foil, titanium foil, etched foil obtained by etching these foils to form fine holes, carbon-coated foil whose surface is coated with a carbon-containing resin layer, foil coated with a PTC (Phase-Transfer Catalyst) layer, and perforated substrates used in lithium ion capacitors. In this specification, a substrate used for a negative electrode may be referred to as a "negative electrode substrate" or a "negative electrode substrate", and a substrate used for a positive electrode may be referred to as a "positive electrode substrate" or a "positive electrode substrate".

[0090] (electrode laminate) The electrode for an electrochemical device according to the present invention can be suitably applied to an electrode laminate. The electrode laminate preferably includes an electrode for an electrochemical device and a sulfide solid electrolyte-containing layer disposed on the electrode for an electrochemical device. In other words, the electrode laminate preferably includes a substrate, an electrode mixture layer containing a sulfide solid electrolyte disposed on the substrate, an insulating layer disposed on the outer periphery of the electrode mixture layer, and a sulfide solid electrolyte-containing layer disposed on the electrode mixture layer and the insulating layer. The substrate, sulfide solid electrolyte, sulfide solid electrolyte-containing layer, and insulating layer are the same as those described above, and therefore redundant description will be omitted.

[0091] (Method for manufacturing electrode laminate and device for manufacturing electrode laminate) The method for producing an electrode laminate of the present invention includes an insulating layer forming step, an electrode mixture layer forming step, and a solid electrolyte layer forming step, and may include a pressing step and other steps as necessary. The electrode laminate manufacturing apparatus according to the present invention preferably includes a container, an insulating layer forming means, an electrode mixture layer forming means, and a solid electrolyte layer forming means, and may include a press means and other means as necessary. The container, insulating layer forming process, insulating layer forming means, electrode composite layer forming process, electrode composite layer forming means, other processes, and other means are the same as those described in the section (Method for manufacturing an electrode for an electrochemical element, and apparatus for manufacturing an electrode for an electrochemical element), so duplicate descriptions will be omitted.

[0092] <Pressing process, pressing method> The pressing step is a step of pressing the electrode mixture layer and the insulating layer. The pressing means is a means for pressing the electrode mixture layer and the insulating layer. The pressing step can be suitably carried out by a pressing means. The pressing step and pressing means are not particularly limited and can be performed using a commercially available pressure molding device, as long as the electrode mixture layer and the insulating layer are pressed in the direction of the substrate, and examples thereof include uniaxial pressing, roll pressing, cold isostatic pressing (CIP), hot pressing, etc. Among these, cold isostatic pressing (CIP), which can apply isostatic pressure, is preferred. The timing of performing the pressing step is not particularly limited and can be appropriately selected depending on the purpose. For example, the electrode mixture layer and the insulating layer may be pressed after being formed on the base, or the solid electrolyte layer may be formed, or the pressing may be performed at both times. By performing a pressing step after forming the electrode mixture layer and the insulating layer on the substrate and before forming the solid electrolyte layer, the average thickness of the electrode mixture layer and the average thickness of the insulating layer can be made approximately equal, and even if high pressure is applied when pressing the solid electrolyte layer provided on the electrode, the pressure load can be distributed. The pressing pressure is not particularly limited and can be appropriately selected depending on the purpose, but it is preferable to perform the pressing at a pressure that can compress the electrode mixture layer while pressing the substrate and the electrode mixture layer together, more specifically, it is preferably 1 MPa or more and 900 MPa or less, more preferably 250 MPa or more and 700 MPa or less.

[0093] [Embodiment in which an insulating layer or an electrode laminate is formed by directly applying a liquid composition to a substrate] FIG. 9 is a schematic diagram showing an example of an insulating layer manufacturing apparatus (liquid ejection apparatus) for carrying out a manufacturing method of an electrode stack according to one embodiment of the present invention.

[0094] The insulating layer manufacturing apparatus 500 includes a conveying unit 5, a printing unit 100, a polymerizing unit 200, a heating unit 300, and rollers 7.

[0095] The transport section 5 transports the printing substrate through the printing section 100, the polymerization section 200, and the heating section 300 in this order at a preset speed. The printed substrate may be a substrate having an electrode mixture layer provided thereon, or may be a substrate having no electrode mixture layer. In the case of a substrate having no electrode mixture layer, the electrode mixture layer is provided after the insulating layer is formed.

[0096] -Printing Department 100- The printing unit 100 includes a printing device 1a, which is an example of a liquid composition application means that performs a liquid composition application step of applying a liquid composition onto a printing substrate, a storage container 1b that stores the liquid composition 6, and a supply tube 1c that supplies the liquid composition stored in the storage container 1b to the printing device 1a.

[0097] The printing unit 100 ejects the liquid composition 6 from the printing device 1a onto a printing substrate to form a thin film of the liquid composition. The storage container 1b may be integrated with the insulating layer manufacturing apparatus or may be detachable from the insulating layer manufacturing apparatus. Alternatively, the storage container 1b may be a container used for adding the liquid to a storage container integrated with the insulating layer manufacturing apparatus or a storage container detachable from the insulating layer manufacturing apparatus.

[0098] The storage container 1b and the supply tube 1c are not particularly limited as long as they can stably store and supply the liquid composition 6, and can be appropriately selected depending on the purpose.

[0099] The materials constituting the storage container 1b and the supply tube 1c preferably have a light-blocking property in the relatively short wavelength region of ultraviolet light and visible light, which is preferable because this prevents the liquid composition 6 from being polymerized by external light.

[0100] - Polymerization section 200 - As shown in FIG. 9, in the case of photopolymerization, the polymerization section 200 has a light irradiation device 2a, which is an example of a liquid composition curing means for performing the liquid composition curing process, and a polymerization inert gas circulation device 2b for circulating a polymerization inert gas.

[0101] The light irradiation device 2a irradiates the thin film of the liquid composition formed by the printing unit 100 with light in the presence of a polymerizable inert gas, thereby photopolymerizing the liquid composition to obtain an insulating layer precursor.

[0102] The light irradiation device 2a is not particularly limited as long as it can initiate and progress polymerization of the compound in the liquid composition, and can be appropriately selected depending on the absorption wavelength of the photopolymerization initiator contained in the liquid composition, and examples thereof include ultraviolet light sources such as high-pressure mercury lamps, metal halide lamps, hot cathode tubes, cold cathode tubes, and LEDs. However, since the shorter the wavelength of the irradiated light, the more likely it is that it will reach deeper layers, it is preferable to select a light source depending on the thickness of the insulating layer to be formed.

[0103] The polymerization inert gas circulation device 2b plays a role in preventing inhibition of the polymerization reaction of the polymerizable compound present near the surface of the liquid composition by reducing the concentration of oxygen having polymerization activity contained in the atmosphere. Examples of the polymerization inert gas include nitrogen, carbon dioxide, and argon.

[0104] The O2 concentration in the polymerization inert gas is preferably less than 20% (an environment with a lower oxygen concentration than the atmosphere), more preferably 0% to 15%, and even more preferably 0% to 5% in order to obtain a greater inhibition reduction effect. Furthermore, the polymerization inert gas circulation device 2b is preferably provided with a temperature control means capable of adjusting the temperature in order to realize stable conditions for the polymerization to proceed.

[0105] In the case of thermal polymerization, the polymerization section 200 may be a heating device. The heating device is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a substrate heater (e.g., a hot plate), an IR heater, and a hot air heater, and these may be used in combination. The heating temperature, time, and light irradiation conditions can be appropriately selected depending on the polymerizable compound contained in the liquid composition and the thickness of the formed film.

[0106] The polymerization unit 200 is not particularly limited and can be appropriately selected depending on the purpose, such as the polymerization initiator used and the polymerization method. For example, in the case of photopolymerization, a light irradiation device that irradiates ultraviolet light with a wavelength of 365 nm for 3 seconds, and in the case of thermal polymerization, a heating device that heats at 150°C in vacuum drying for 12 hours, etc. can be used.

[0107] -Heating section 300- The heating section 300 has a heating device 3a, which is an example of a solvent removal means for carrying out the solvent removal step. 9, the heating device 3a heats the insulating layer precursor formed in the polymerization section 200 to dry and remove the remaining solvent. At this time, the solvent removal may be performed under reduced pressure.

[0108] The heating section 300 also carries out a polymerization promotion step in which the insulating layer precursor is heated by the heating device 3a to further promote the curing (polymerization) reaction carried out in the polymerization section 200, and an initiator removal step in which the photopolymerization initiator remaining in the insulating layer precursor is heated by the heating device 3a to dry and remove it. Note that these polymerization promotion step and initiator removal step do not have to be carried out simultaneously with the solvent removal step, and may be carried out before or after the solvent removal step.

[0109] After the solvent removal step, the heating unit 300 performs a polymerization completion step of heating the insulating layer under reduced pressure. The heating temperature and time can be appropriately selected depending on the boiling point of the solvent contained in the insulating layer precursor and the thickness of the formed film.

[0110] FIG. 10 is a schematic diagram showing another example of an insulating layer manufacturing apparatus (liquid ejection apparatus) for carrying out a manufacturing method of an electrode stack according to one embodiment of the present invention.

[0111] The liquid ejection device 300 ′ controls the pump 310 and the valves 311 and 312 to allow the liquid composition to circulate through the liquid ejection head 306 , the liquid ejection head tank 307 , and the tube 308 .

[0112] The liquid ejection device 300' is provided with an external tank 313, and when the liquid composition in the liquid ejection head tank 307 decreases, it is possible to supply the liquid composition from the external tank 313 to the tank 307 by controlling the pump 310 and the valves 311, 312, and 314. By using the insulating layer manufacturing device, the liquid composition can be ejected onto a target object.

[0113] The insulating layer manufacturing apparatus 500 may be provided with a mechanism for capping the nozzle to prevent the liquid composition 6 from drying out when it is not being ejected from the liquid ejection head.

[0114] FIG. 11 is a schematic diagram (part 1) illustrating a method for producing an electrode for an electrochemical device according to one embodiment of the present invention.

[0115] The method for producing an electrode for an electrochemical device 210 having an insulating layer provided on a substrate includes a step of sequentially discharging the liquid composition 12A onto a substrate 211 using a liquid discharge device 300'. First, an elongated substrate 211 is prepared. Then, the substrate 211 is wound around a cylindrical core and set on a feed roller 304 and a take-up roller 305 so that the side on which the insulating layer 212 is to be formed faces upward in FIG. 11. Here, the feed roller 304 and the take-up roller 305 rotate counterclockwise to transport the substrate 211 from right to left in FIG. 11. Then, as in FIG. 10, droplets of the liquid composition 12A are ejected onto the substrates 211 that are being transported sequentially from a liquid ejection head 306 installed above the substrate 211 between the feed roller 304 and the take-up roller 305. A plurality of liquid ejection heads 306 may be installed in a direction substantially parallel to or substantially perpendicular to the transport direction of the substrate 211 . Next, the substrate 211 onto which the droplets of the liquid composition 12A have been ejected is transported to a polymerization section 309 by a delivery roller 304 and a take-up roller 305. As a result, the liquid composition 12A is polymerized to form an insulating layer 212, and an electrochemical device electrode 210 having an insulating layer provided on the substrate is obtained. Thereafter, the electrochemical device electrode 210 is cut to a desired size by punching or the like.

[0116] The overlapping portion 309 may be provided either above or below the base 211, or a plurality of overlapping portions may be provided. The polymerization unit 309 is not particularly limited and can be appropriately selected depending on the purpose as long as it does not come into direct contact with the liquid composition 12A, and examples thereof include a resistance heater, an infrared heater, a fan heater, etc. in the case of thermal polymerization, and an ultraviolet ray irradiation device, etc. In addition, a plurality of polymerization units 309 may be installed. The conditions for heating or light irradiation are not particularly limited and can be appropriately selected depending on the purpose.

[0117] FIG. 12 is a schematic diagram showing yet another example of an insulating layer manufacturing apparatus (liquid ejection apparatus) for carrying out a method for manufacturing an electrode stack according to one embodiment of the present invention. Liquid ejection device 300A' and liquid ejection device 300B' may be used in combination. That is, the tanks may supply the liquid composition from external tanks 313A and 313B connected to tanks 307A and 307B, and the liquid ejection head may have multiple heads 306A and 306B. Accordingly, tubes 308A and 308B, valves 311A, 311B, 312A, 312B, and 314A, and pumps 310A and 310B may be provided.

[0118] [Embodiments in which an insulating layer or an electrode laminate is formed by indirectly applying a liquid composition to a substrate] Fig. 13 is a structural diagram (part 1) showing an example of a printing unit that employs an inkjet system and a transfer system as a liquid composition applying means in an insulating layer manufacturing apparatus according to one embodiment of the present invention. The printing unit in Fig. 13 uses a drum-shaped intermediate transfer body.

[0119] The printing unit 400' is an inkjet printer that transfers a liquid composition or an insulating layer onto a substrate via an intermediate transfer body 4001, thereby forming an insulating layer on the substrate.

[0120] The printing section 400 ′ includes an inkjet section 420 , a transfer drum 4000 , a pre-treatment unit 4002 , an absorption unit 4003 , a heating unit 4004 , and a cleaning unit 4005 .

[0121] The inkjet unit 420 includes a head module 422 that holds a plurality of heads 101 .

[0122] The head 101 ejects a liquid composition onto an intermediate transfer body 4001 supported by a transfer drum 4000, forming a liquid composition film on the intermediate transfer body 4001. Each head 101 is a line head, and nozzles are arranged over a range that covers the width of the recording area of ​​a substrate of the largest usable size. The head 101 has a nozzle surface on its underside on which nozzles are formed, and the nozzle surface faces the surface of the intermediate transfer body 4001 via a minute gap. In this embodiment, the intermediate transfer body 4001 is configured to move cyclically on a circular orbit, so the multiple heads 101 are arranged radially.

[0123] The transfer drum 4000 faces the impression cylinder 621 and forms a transfer nip. The pretreatment unit 4002 applies, for example, a reaction liquid onto the intermediate transfer body 4001 to increase the viscosity of the liquid composition before the head 101 ejects the liquid composition.

[0124] The absorption unit 4003 absorbs liquid components from the liquid composition on the intermediate transfer member 4001 before transfer.

[0125] The heating unit 4004 heats the liquid composition on the intermediate transfer body 4001 before transfer. By heating the liquid composition, the liquid composition is thermally polymerized to form an insulating layer. In addition, the solvent is removed, improving transferability to the substrate.

[0126] A cleaning unit 4005 cleans the surface of the intermediate transfer body 4001 after transfer, and removes foreign matter such as ink and dust remaining on the intermediate transfer body 4001 .

[0127] The outer peripheral surface of the impression cylinder 621 is in pressure contact with the intermediate transfer body 4001, and the insulating layer on the intermediate transfer body 4001 is transferred to the substrate when the substrate passes through the transfer nip between the impression cylinder 621 and the intermediate transfer body 4001. The impression cylinder 621 may be configured to have at least one gripping mechanism on its outer peripheral surface that holds the leading end of the substrate.

[0128] Fig. 14 is a structural diagram (part 2) showing an example of a printing unit that employs an inkjet system and a transfer system as a liquid composition applying means in an insulating layer manufacturing apparatus according to one embodiment of the present invention. The printing unit in Fig. 14 uses an intermediate transfer body in the form of an endless belt.

[0129] The printing unit 400 ″ is an inkjet printer that transfers a liquid composition or an insulating layer onto a substrate via an intermediate transfer belt 4006 to form an insulating layer.

[0130] The printing section 400'' includes an inkjet section 420, a transfer roller 622, an intermediate transfer belt 4006, a heating unit 4007, a cleaning roller 4008, a drive roller 4009a, an opposing roller 4009b, a shape maintaining roller 4009c, a shape maintaining roller 4009d, a shape maintaining roller 4009e, and a shape maintaining roller 4009f.

[0131] The printing unit 400'' ejects droplets of a liquid composition from a plurality of heads 101 provided in the inkjet unit 420 onto the outer circumferential surface of the intermediate transfer belt 4006. The liquid composition on the intermediate transfer belt 4006 is heated by a heating unit 4007 and thermally polymerized to form an insulating layer. At the transfer nip where the intermediate transfer belt 4006 faces the transfer roller 622, the insulating layer on the intermediate transfer belt 4006 is transferred to the substrate. After transfer, the surface of the intermediate transfer belt 4006 is cleaned by a cleaning roller 4008.

[0132] The intermediate transfer belt 4006 is stretched over a drive roller 4009a, an opposing roller 4009b, multiple shape maintaining rollers 4009c, 4009d, 4009e, 4009f, and multiple support rollers 4009g, and moves in the direction of the arrow in Fig. 14. The support roller 4009g, which is provided opposite the head 101, maintains the tension state of the intermediate transfer belt 4006 when ink droplets are ejected from the head 101.

[0133] (electrochemical element) The electrochemical device of the present invention preferably has an electrode laminate, and may further have an exterior packaging, if necessary. The electrode laminate is the same as that described in the (electrode laminate) section, and therefore a duplicate description will be omitted.

[0134] Here, an embodiment of an electrochemical device according to the present invention will be described with reference to the drawings, although the present invention is not limited to these embodiments.

[0135] 15 is a schematic cross-sectional view showing an electrochemical element according to one embodiment of the present invention. The electrochemical element 45 includes a first substrate 21, a first electrode mixture layer 20 disposed on the first substrate 21, an insulating layer 10 disposed on the outer periphery of the first electrode mixture layer 20, a solid electrolyte layer 30 disposed on the first electrode mixture layer 20 and the insulating layer 10, a second electrode mixture layer 40 disposed on the solid electrolyte layer 30, and a second substrate 31 disposed on the second electrode mixture layer. The electrochemical element 45 is a single cell layer, which can be stacked to form a stacked battery.

[0136] Although FIG. 15 illustrates a configuration in which the electrode composite layer 20, the insulating layer 10, and the solid electrolyte layer 30 are provided on one side of the first substrate 21, the electrode composite layer 20, the insulating layer 10, and the solid electrolyte layer 30 may be provided on both opposing sides of the first substrate 21, and a stacked battery having this configuration may be formed.

[0137] FIG. 16 is a schematic cross-sectional view showing an example of an all-solid-state battery, which is an electrochemical element according to one embodiment of the present invention. The all-solid-state battery shown in FIG. 16 includes a positive electrode (electrode mixture layer) 20, a negative electrode (electrode mixture layer) 40, a solid electrolyte layer 30, a lead wire 50, a lead wire 51, and a casing 60.

[0138] The positive electrode (electrode mixture layer) 20 includes a positive electrode substrate 21 and an insulating layer 10 disposed on the positive electrode substrate 21. A lead wire 50 is connected to the positive electrode substrate 21, and a lead wire 51 is connected to the negative electrode substrate 41. The lead wires 50 and 51 are drawn out to the outside of the exterior casing 60.

[0139] Here, in the all-solid-state battery, a positive electrode (electrode mixture layer) 20 and a negative electrode (electrode mixture layer) 40 are stacked with a solid electrolyte layer 30 interposed therebetween, and the positive electrode (electrode mixture layer) 20 is disposed on both sides of the negative electrode (electrode mixture layer) 40. There is no particular limit to the number of positive electrodes (electrode mixture layers) 20 and negative electrodes (electrode mixture layers) 40 stacked. Furthermore, the number of positive electrodes (electrode mixture layers) 20 and the number of negative electrodes (electrode mixture layers) 40 may be the same or different.

[0140] The exterior packaging is not particularly limited as long as it can seal the electrode laminate, and any known exterior packaging can be appropriately selected depending on the purpose.

[0141] The shape of the electrochemical element is not particularly limited and can be appropriately selected depending on the purpose. Examples include laminate type, cylinder type, and coin type.

[0142] In electrochemical elements where short circuits due to dendrite precipitation may occur, the negative electrode composite layer is typically configured to be larger than the positive electrode composite layer. In this case, if the positive electrode current collector and the negative electrode current collector are approximately the same size, an excess portion where the positive electrode composite layer is not formed is generated on the positive electrode current collector in the region where the negative electrode composite layer of the negative electrode faces. From the viewpoint of electrical element characteristics, the insulating layer is preferably provided on the excess portion of the positive electrode, i.e., on the outer periphery of the positive electrode composite layer. Note that, if the electrochemical element is configured such that the negative electrode composite layer is smaller than the positive electrode composite layer, the insulating layer is preferably provided on the excess portion of the negative electrode, i.e., on the outer periphery of the negative electrode composite layer.

[0143] (Method for manufacturing electrochemical elements and apparatus for manufacturing electrochemical elements) The method for manufacturing an electrochemical device according to the present invention preferably includes an insulating layer forming step, an electrode mixture layer forming step, a pressing step, a solid electrolyte layer forming step, an element forming step, and an electrode processing step, and may include other steps as necessary.

[0144] The electrochemical element manufacturing apparatus according to the present invention preferably includes an insulating layer forming means, an electrode mixture layer forming means, a pressing means, a solid electrolyte layer forming means, an element forming means, and an electrode processing means, and may include other means as necessary.

[0145] The insulating layer forming step, insulating layer forming means, electrode composite layer forming step, electrode composite layer forming means, pressing step, pressing means, solid electrolyte layer forming step, solid electrolyte layer forming means, other steps, and other means are the same as those described in the items (Method for manufacturing an electrode for an electrochemical element, and apparatus for manufacturing an electrode for an electrochemical element) and (Method for manufacturing an electrode laminate, and apparatus for manufacturing an electrode laminate), and therefore redundant descriptions will be omitted.

[0146] <Device Fabrication Process and Device Fabrication Means> The device fabrication step is a step of manufacturing an electrochemical device using the electrode laminate. The device fabrication means is a means for producing an electrochemical device using the electrode laminate.

[0147] The method for producing an electrochemical element using an electrode laminate is not particularly limited, and a known method for producing an electrochemical element can be appropriately selected depending on the purpose. For example, a method for producing an energy storage element can be exemplified, in which a counter electrode is provided, the electrode laminate is wound or laminated, or the electrode laminate is housed in a container. The element fabrication step does not necessarily include all steps of fabrication, but may include only a part of the steps of fabrication.

[0148] <Electrode processing step and electrode processing means> The electrode processing step is a step of processing the electrode on which the insulating layer has been formed, which is performed after the liquid composition application step in the insulating layer forming step, and may include at least one of a cutting step, a folding step, and a bonding step.

[0149] The electrode processing means processes the electrode on which the insulating layer is formed, and may include at least one of cutting means, folding means, and bonding means.

[0150] The electrode processing means can, for example, cut the electrodes on which the insulating layer is formed to produce an electrode stack. The electrode processing means can, for example, wind or stack the electrode stack on which the insulating layer is formed. The electrode processing means has, for example, an electrode processing device, and performs cutting, zigzag folding, stacking, or winding of the electrode stack on which the insulating layer is formed according to the desired battery form.

[0151] The use of the electrochemical element is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include mobile objects such as vehicles, smartphones, notebook computers, pen-input personal computers, mobile personal computers, electronic book players, mobile phones, mobile fax machines, mobile copiers, mobile printers, headphone stereos, video movie players, LCD televisions, handheld vacuum cleaners, portable CDs, minidiscs, transceivers, electronic organizers, calculators, memory cards, portable tape recorders, radios, backup power supplies, motors, lighting equipment, toys, game devices, clocks, strobe lights, cameras, and other electrical equipment. Of these, vehicles and electrical equipment are preferred.

[0152] Examples of mobile objects include standard automobiles, large special purpose automobiles, small special purpose automobiles, trucks, large motorcycles, and standard motorcycles. Here, an embodiment of a moving body that is an electrochemical element according to the present invention will be described with reference to the drawings, although the present invention is not limited to these embodiments.

[0153] [Moving object] FIG. 17 is a schematic diagram showing an example of a moving body that is an electrochemical device according to one embodiment of the present invention.

[0154] The moving object 70 is, for example, an electric vehicle. The moving object 70 includes a motor 71, an electrochemical device 72, and wheels 73.

[0155] The electrochemical element 72 is an electrochemical element according to the present invention. The electrochemical element 72 supplies power to the motor 71 to drive the motor 71. The driven motor 71 can drive the wheels 73, and as a result, the mobile object 70 can move.

[0156] Since the mobile object 70 is equipped with an electrochemical element 72, short circuits between the positive and negative electrodes are prevented, and the mobile object can be driven by power from the electrochemical element, which has excellent battery characteristics, allowing it to move safely and efficiently.

[0157] The mobile object 70 is not limited to an electric vehicle, but may also be a PHEV, HEV, or a locomotive or motorcycle that can run using a diesel engine and an electrochemical device in combination. Furthermore, the mobile object 70 may be a transport robot used in a factory or the like that can run using only an electrochemical device or a combination of an engine and an electrochemical device. Furthermore, the mobile object 70 may be an object that does not move as a whole, but only a part of it, such as an assembly robot that is arranged on a factory production line and that can operate an arm or the like using only an electrochemical device or a combination of an engine and an electrochemical device.

[0158] <Base> The substrate is not particularly limited as long as it has electron conductivity and is stable to the applied potential, and can be appropriately selected depending on the purpose. Examples include aluminum foil, copper foil, stainless steel foil, titanium foil, etched foil obtained by etching these foils to form fine holes, carbon-coated foil whose surface is coated with a carbon-containing resin layer, foil coated with a PTC (Phase-Transfer Catalyst) layer, and perforated substrates used in lithium ion capacitors. In this specification, a substrate used for a negative electrode may be referred to as a "negative electrode substrate" or a "negative electrode substrate", and a substrate used for a positive electrode may be referred to as a "positive electrode substrate" or a "positive electrode substrate". The substrate is a highly conductive material, and aluminum is used for the positive electrode substrate, and copper is used for the negative electrode substrate, but the substrate according to this embodiment is not limited to these materials. [Example]

[0159] (Synthesis Example 1: Synthesis of Inorganic Solid Electrolyte 1) Inorganic solid electrolyte 1 was synthesized from the argyrodite-type sulfide solid electrolyte Li6PS5Cl (LPSC) according to the literature 1 (Nataly Carolina Rosero-Navarro et al., Journal of Power Sources 396 (2018) 33.).

[0160] <Preparation of Liquid Composition for Forming Solid Electrolyte Layer> 45% by mass of inorganic solid electrolyte 1 (average particle size D50: approximately 0.6 μm) as the solid electrolyte, 4.5% by mass of Solsperse 3000 (manufactured by Lubrizol) as the dispersant, and 50.5% by mass of p-cymene (manufactured by Kanto Chemical) as the dispersion medium were added, and the mixture was dispersed using a high-speed rotary homogenizer (manufactured by Kinematica, MT3100S2) at a rotation speed of 30,000 rpm for 1 hour to obtain a liquid composition for forming a solid electrolyte layer.

[0161] <Preparation of Liquid Composition for Forming Electrode Mixture Layer> Using a bead mill, 50% by mass of nickel-based positive electrode active material (NCA, manufactured by JFE Mineral Co., Ltd.) was pulverized and crushed in ethyl lactate containing 0.5% by mass of SC-0708A (manufactured by NOF Corporation) as a dispersant, and dispersed in the ethyl lactate. This was further mixed with 1.5% by mass of carbon black (manufactured by Denka Co., Ltd.) and 1.5% by mass of a polyamideimide compound (PAI) represented by the following general formula 1, to obtain a liquid composition for forming an electrode mixture layer. The resulting liquid composition for forming an electrode mixture layer had a mode diameter of the active material of 9.72 μm and a viscosity at 25°C of 10.7 mPa s.

[0162] [ka]

[0163] Example 1 - Formation of electrode mixture layer - The liquid composition for forming an electrode mixture layer was applied onto an aluminum foil (manufactured by UACJ Foil Corporation) as a substrate using an inkjet device (device name: EV1000), and then heated and dried at 80°C to form an electrode mixture layer.

[0164] The surface unevenness difference and porosity difference of the formed electrode mixture layer were measured as follows, and the surface unevenness difference was greater than 0 μm and less than 1 μm, and the porosity difference was 1%.

[0165] --Method for measuring surface unevenness-- The difference in surface roughness of the electrode mixture layer was measured from the surface profile using a laser microscope. As shown in Figure 2A, the highest point was defined as a convex portion, and the lowest point was defined as a concave portion.

[0166] --Method for measuring porosity difference-- The base resin for 53-type embedding epoxy resin (Lot No. 53512040149, Sankei Co., Ltd.) and the curing agent (Lot No. 53572040342, Sankei Co., Ltd.) were thoroughly mixed at a volume ratio of 1:2, and the electrode composite layer was embedded in the resin using a vacuum impregnation device (Buehler Vacuum Impregnation Equipment I, Sankei Co., Ltd.) and allowed to cure for 24 hours. The electrode composite layer embedded in the epoxy resin was processed using a cross-section polisher (JEOL Ltd.), and the cross section was observed using a tabletop scanning electron microscope (SEM) (Phenom Prox, Jasco International Inc.), and SEM photographs of the electrode composite layer were taken. The SEM photograph of the obtained electrode mixture layer was binarized using image processing software (Image-Pro Premier version 9.2 64-bit, manufactured by Hakuto Co., Ltd.) as shown in Figure 18. The areas of the particle-derived regions and the void-derived regions were then determined, and the void-derived regions were divided by the total area to calculate the porosity of the first convex and non-convex portions. While the above-described method involves binarization using software, it is also possible to determine, for example, regions in the binarized image with a density greater than 50% as particles or voids, and regions with a density less than 50% as voids or particles. In Figure 18, particles 20 are represented by white areas, and voids 21 are represented by black areas.

[0167] - Formation of solid electrolyte layer - On the electrode mixture layer, the liquid composition for forming a solid electrolyte layer was applied in a single application amount of 5.1 mg / cm using an inkjet device (device name: EV1000). 2 The solution was then heated and dried at 80° C. to form a solid electrolyte layer, thereby producing an electrode 1 for an electrochemical device.

[0168] The thicknesses of the convex and concave portions of the formed solid electrolyte layer were measured as follows. The thickness (A) of the convex portions (hereinafter referred to as "SE thickness (A)") was 15 μm, the thickness (B) of the concave portions (hereinafter referred to as "SE thickness (B)") was 15 μm, and the thickness ratio (A / B) was 1. The amount of the liquid composition for forming a solid electrolyte layer that was applied was measured as follows. The amount applied in one application was 5.1 mg / cm. 2 It was.

[0169] --Method for measuring SE film thickness (A) and SE film thickness (B)-- The solid electrolyte layer was cross-sectionally processed using a CP at 6 kV for 2 h and then observed using a SEM. The distance from the electrode surface to the solid electrolyte layer surface in the perpendicular direction to the metal foil was measured at 0.5 mm intervals, and the SE film thickness (A) and SE film thickness (B) were measured.

[0170] --Method for measuring the amount applied at one time-- The applied liquid composition for forming a solid electrolyte layer was collected from the container and measured using a balance (device name).

[0171] Example 2 An electrode 2 for an electrochemical element was produced in the same manner as in Example 1, except that the electrode mixture layer was formed so that the difference in surface irregularities on the electrode mixture layer was 15 μm.

[0172] Example 3 In Example 2, the electrode mixture layer was formed so that the porosity difference between the electrode mixture layers was 13%, and the amount of the solid electrolyte layer-forming liquid composition applied in one application was 5.45 mg / cm 2 After the first application, leave sufficient intervals between applications and apply 5.45 mg / cm 2 An electrode 3 for an electrochemical element was produced in the same manner as in Example 2, except that a second coating was performed to form a solid electrolyte layer.

[0173] Example 4 In Example 2, the electrode mixture layer was formed so that the difference in surface roughness of the electrode mixture layer was 10 μm and the difference in porosity was 4.5%, and the amount of the solid electrolyte layer-forming liquid composition applied in one application was 8 mg / cm 2 After the first application, leave sufficient intervals between applications and apply 0.34 mg / cm 2 An electrode 4 for an electrochemical element was produced in the same manner as in Example 2, except that a second coating was performed to form a solid electrolyte layer.

[0174] Example 5 In Example 2, the electrode mixture layer was formed so that the difference in surface irregularities of the electrode mixture layer was 5 μm and the difference in porosity was 5%, and the amount of the solid electrolyte layer-forming liquid composition applied at one time was 10 mg / cm 2 An electrode for electrochemical element 5 was produced in the same manner as in Example 2, except that the solid electrolyte layer was formed by coating once with the solution of 100% by weight.

[0175] Example 6 In Example 2, the electrode mixture layer was formed so that the difference in surface irregularities of the electrode mixture layer was 20 μm and the difference in porosity was 3%, and the amount of the solid electrolyte layer-forming liquid composition applied in one application was 9.2 mg / cm 2 An electrode for an electrochemical element 6 was produced in the same manner as in Example 2, except that the solid electrolyte layer was formed by coating once with the solution of 100% by weight.

[0176] Example 7 In Example 2, the electrode mixture layer was formed so that the difference in surface irregularities of the electrode mixture layer was 20 μm and the difference in porosity was 9.8%, and the amount of the solid electrolyte layer-forming liquid composition applied in one application was 4.6 mg / cm 2 After the first application, leave sufficient intervals between applications and apply 4.6 mg / cm 2 An electrode 7 for an electrochemical element was produced in the same manner as in Example 2, except that a second coating was performed to form a solid electrolyte layer.

[0177] Example 8 In Example 2, the electrode mixture layer was formed so that the difference in surface irregularities of the electrode mixture layer was 6 μm and the difference in porosity was 5%, and a positive electrode insulating frame was provided on the outer periphery of the electrode mixture layer, and the amount of the solid electrolyte layer-forming liquid composition applied in one application was 6.8 mg / cm 2 An electrode for an electrochemical element 8 was produced in the same manner as in Example 2, except that the solid electrolyte layer was formed by coating once with the solution of 100% by weight.

[0178] Example 9 An electrode for electrochemical elements 9 was produced in the same manner as in Example 6, except that the electrode mixture layers were formed so that the porosity difference of the electrode mixture layers was 11%.

[0179] Example 10 In Example 1, the amount of the solid electrolyte layer-forming liquid composition applied in one application was 0.34 mg / cm 2 An electrode 10 for an electrochemical element was produced in the same manner as in Example 1, except that the solid electrolyte layer was formed by coating once with the solution of 100% by weight.

[0180] Example 11 In Example 1, the amount of the solid electrolyte layer-forming liquid composition applied in one application was 10 mg / cm 2 An electrode for an electrochemical element 11 was produced in the same manner as in Example 1, except that the solid electrolyte layer was formed by coating once with the solution of 100% by weight.

[0181] (Comparative Example 1) An electrode 12 for an electrochemical device was produced in the same manner as in Example 2, except that the solid electrolyte layer was formed by applying the liquid composition for forming a solid electrolyte layer by spin coating.

[0182] (Comparative Example 2) In Example 2, the electrode mixture layer was formed so that the difference in surface roughness of the electrode mixture layer was 20 μm, and the amount of the solid electrolyte layer-forming liquid composition applied in one application was 11 mg / cm 2 An electrode 13 for an electrochemical element was produced in the same manner as in Example 2, except that the solid electrolyte layer was formed by coating once with the solution of 100% by weight.

[0183] (Comparative Example 3) In Example 3, the electrode mixture layer was formed so that the porosity difference between the electrode mixture layers was 8%, and the amount of the solid electrolyte layer-forming liquid composition applied in one application was 3 mg / cm 2 2 After the first application, leave sufficient intervals between applications and apply 12 mg / cm 2 An electrode 14 for an electrochemical element was produced in the same manner as in Example 3, except that a second coating was performed to form a solid electrolyte layer.

[0184] Comparative Example 4 In Example 1, the amount of the solid electrolyte layer-forming liquid composition applied in one application was 0.32 mg / cm 2 An electrode 15 for an electrochemical element was produced in the same manner as in Example 1, except that the solid electrolyte layer was formed by coating once with the solution of 100% by weight.

[0185] The input / output characteristics of the electrodes for electrochemical devices 1 to 15 obtained in Examples 1 to 11 and Comparative Examples 1 to 4 were evaluated as follows. The evaluation results are shown in Table 1.

[0186] <Input / output characteristics> A charge / discharge test was carried out on the all-solid-state lithium secondary battery evaluation cells having each electrode for electrochemical devices using a charge / discharge tester (TOSCAT-3100, manufactured by Toyo Systems Co., Ltd.) over a voltage range of 3.7 V to 2.4 V (in a thermostatic chamber at 25°C), and the 1.0 C discharge capacity and 0.1 C discharge capacity in the discharged state (output) and charged state (input) were measured. As input / output characteristics, the capacity retention rate was calculated using the following formula (1), and the input / output characteristics were evaluated based on the following evaluation criteria. The results are shown in Table 1. In all of the Examples and Comparative Examples, the capacity retention rate in the discharged state (output) and the capacity retention rate in the charged state (input) were the same value. Capacity maintenance rate = 1.0C discharge capacity / 0.1C discharge capacity...Equation (1) [Evaluation criteria] A: Capacity retention rate is 70% or more B: Capacity retention rate is 50% or more but less than 70% C: Capacity retention rate is less than 50%

[0187] [Table 1]

[0188] The embodiments of the present invention are as follows, for example. <1> A method for manufacturing an electrode for an electrochemical element, the method comprising: a substrate; an electrode mixture layer containing an active material on the substrate; and a solid electrolyte layer containing a solid electrolyte on the electrode mixture layer, the method comprising: the electrode mixture layer has an uneven structure, A liquid composition for forming a solid electrolyte layer containing the solid electrolyte and a dispersion medium was applied onto the electrode mixture layer by an inkjet method in an amount of 0.34 mg / cm 2 in one application. 2 More than 10mg / cm 2 forming the solid electrolyte layer by applying the following: A method for producing an electrode for an electrochemical element, wherein the liquid composition for forming a solid electrolyte layer has a viscosity of 4 mPa·s or more and 20 mPa·s or less. <2> The solid electrolyte layer has an average thickness of 2 μm or more and 40 μm or less. <1> A method for producing the electrode for an electrochemical element according to claim 1. <3> The difference in unevenness on the surface of the electrode mixture layer is 5 μm or more. <1> or <2> A method for producing the electrode for an electrochemical element according to claim 1. <4> The porosity difference of the electrode mixture layer is 0% or more and 10% or less. <1> from <3> 10. A method for producing the electrode for an electrochemical element according to claim 9. <5> an insulating layer is disposed on the outer periphery of the electrode mixture layer; <1> from <4> 10. A method for producing the electrode for an electrochemical element according to claim 9. <6> a step of applying an electrode mixture layer-forming composition containing an active material onto a substrate using an inkjet method to form an electrode mixture layer; <1> from <5> 10. A method for producing the electrode for an electrochemical element according to claim 9. <7> A liquid composition for forming a solid electrolyte layer containing the solid electrolyte and a dispersion medium was applied onto the electrode mixture layer by an inkjet method in an amount of 0.34 mg / cm 2 in one application. 2 More than 10mg / cm 2 The coating is repeated as follows to form a solid electrolyte laminate having two or more solid electrolyte layers: <1> from <6> 10. A method for producing the electrode for an electrochemical element according to claim 9. <8> a liquid composition for forming a solid electrolyte layer, which contains a solid electrolyte different from the solid electrolyte, is applied onto the solid electrolyte layer to form another solid electrolyte layer; <1> from <7> 10. A method for producing the electrode for an electrochemical element according to claim 9. <9> an electrode having a substrate and an electrode mixture layer containing an active material on the substrate; a solid electrolyte layer on the electrode mixture layer, The electrode mixture layer has protrusions of 5 μm or more, The electrode for an electrochemical element, wherein the ratio (A / B) of the average thickness (A) of the convex portions to the average thickness (B) of the concave portions in the solid electrolyte layer is 0.8 or more and 1.2 or less. <10> The porosity difference of the electrode mixture layer is 0% or more and 10% or less. <9> The electrode for an electrochemical element according to claim 1. <11> an insulating layer is disposed on the outer periphery of the electrode mixture layer in the electrode; <9> or <10> The electrode for an electrochemical element according to claim 1. <12> <9> from <11> 10. An electrochemical device comprising the electrode for an electrochemical device according to any one of claims 1 to 9. <13> <12> An electrical device comprising the electrochemical element according to claim 1. <14> <12> A mobile object comprising the electrochemical device according to claim 1. <15> It is a vehicle, <14> A mobile object according to the present invention. [Explanation of symbols]

[0189] 10. Insulating resin layer 20 First electrical composite layer 21 First base 22 Adhesive layer 23 Opening 24 Material 25 Electrodes for electrochemical devices 30 Sulfide solid electrolyte containing layer 31 Second base 35 Electrode stack 40 Second electrode mixture layer 41 Second electrode 45 Electrochemical elements 500 Insulating resin layer manufacturing equipment 100 printing department 1a Printing device 1b Containment vessel 1c Supply Tube 200 Polymerization Part 2a Light irradiation device 2b Polymerization inert gas circulation device 300 Heating section 3a Heating device 5. Conveyor 6 Liquid composition 7. Laura [Prior art documents] [Patent documents]

[0190] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-22827

Claims

1. A method for manufacturing an electrode for an electrochemical element, the method comprising: a substrate; an electrode mixture layer containing an active material on the substrate; and a solid electrolyte layer containing a solid electrolyte on the electrode mixture layer, the method comprising: the electrode mixture layer has an uneven structure, A liquid composition for forming a solid electrolyte layer containing the solid electrolyte and a dispersion medium was applied onto the electrode mixture layer by an inkjet method in an amount of 0.34 mg / cm 2 in one application. ２ 10mg / cm or more ２ forming the solid electrolyte layer by applying the following: The method for producing an electrode for an electrochemical element, wherein the viscosity of the liquid composition for forming a solid electrolyte layer is 4 mPa·s or more and 20 mPa·s or less.

2. 2. The method for producing an electrode for an electrochemical element according to claim 1, wherein the solid electrolyte layer has an average thickness of 2 μm or more and 40 μm or less.

3. 3. The method for producing an electrode for an electrochemical element according to claim 1, wherein the difference in unevenness of the surface of the electrode mixture layer is 5 [mu]m or more.

4. The method for producing an electrode for an electrochemical element according to claim 1 or 2, wherein the difference in porosity of the electrode mixture layer is 0% or more and 10% or less.

5. The method for producing an electrode for an electrochemical element according to claim 1 or 2, wherein an insulating layer is disposed on the outer periphery of the electrode mixture layer.

6. 3. The method for producing an electrode for an electrochemical element according to claim 1, further comprising the step of applying an electrode mixture layer-forming composition containing an active material onto a substrate by an inkjet method to form an electrode mixture layer.

7. A liquid composition for forming a solid electrolyte layer containing the solid electrolyte and a dispersion medium was applied onto the electrode mixture layer by an inkjet method in an amount of 0.34 mg / cm 2 in one application. ２ 10mg / cm or more ２ 3. The method for producing an electrode for an electrochemical element according to claim 1, wherein the coating is repeated as follows to form a solid electrolyte laminate having two or more solid electrolyte layers.

8. 3. The method for producing an electrode for an electrochemical element according to claim 1, wherein a solid electrolyte layer-forming liquid composition containing another solid electrolyte different from the solid electrolyte is applied onto the solid electrolyte layer to form another solid electrolyte layer.

9. an electrode having a substrate and an electrode mixture layer containing an active material on the substrate; a solid electrolyte layer on the electrode mixture layer, the electrode mixture layer has protrusions of 5 μm or more, The electrode for an electrochemical element, wherein the ratio (A / B) of the average film thickness (A) of the convex portions to the average film thickness (B) of the concave portions in the solid electrolyte layer is 0.8 or more and 1.2 or less.

10. 10. The electrode for an electrochemical element according to claim 9, wherein the difference in porosity of the electrode mixture layer is 0% or more and 10% or less.

11. The electrode for an electrochemical element according to claim 9 or 10, wherein an insulating layer is disposed on the outer periphery of the electrode mixture layer in the electrode.

12. An electrochemical device comprising the electrode for an electrochemical device according to claim 9 or 10.

13. An electrical device comprising the electrochemical device according to claim 12.

14. A mobile object comprising the electrochemical device according to claim 12.

15. The mobile object according to claim 14, which is a vehicle.

Images