Liquid composition and method for producing the same, container, and device and method for producing solid electrolyte layer

Abstract

To provide a liquid composition having satisfactory to-be-ejected property in an ink jet system, and furthermore enabling a solid electrolyte layer having satisfactory ion conduction property to be obtained.SOLUTION: A liquid composition is provided, including: a solvent; an inorganic solid electrolyte; and a dispersant. The dispersant is solved into the solvent, and a particle diameter (D10) at a volume fraction 10% of a solid content included in the liquid composition, which is measured by a layer diffraction, a particle diameter (D50) at a volume fraction 50%, a particle diameter (D90) at a volume fraction 90%, and a mode diameter (Dm) satisfy the following equation: D90 / D10>10, D50<1 μm, and Dm<2 μm.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a liquid composition, a method for producing the same, a container, and an apparatus and method for producing a solid electrolyte layer or an electrode mixture layer. [Background technology]

[0002] Electrochemical devices 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. In particular, demand for lithium-ion secondary batteries for automotive applications is expected to expand due to the recent need for low environmental impact. Against this backdrop, there is a need for further improvements in the safety and energy density of lithium-ion secondary batteries, and active efforts are underway to commercialize all-solid-state batteries that replace the existing liquid electrolyte with a solid electrolyte.

[0003] The solid electrolyte layer in all-solid-state batteries is required to have high Li-ion conductivity.

[0004] For example, as a technology aimed at providing an all-solid-state battery having a solid electrolyte layer with low ion conduction resistance and a high filling rate, a technology using solid electrolyte particles with a large average particle size and solid electrolyte particles with a small average particle size has been proposed (see, for example, Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a liquid composition that has good ejection properties in an ink jet system and that can provide a solid electrolyte layer with good ion conductivity. [Means for solving the problem]

[0006] The liquid composition of the present invention as a means for solving the above-mentioned problems is a liquid composition comprising a solvent, an inorganic solid electrolyte, and a dispersant, wherein the dispersant is dissolved in the solvent and has a particle diameter (D 10 ), volume fraction 50% particle diameter (D 50 ), volume fraction 90% particle diameter (D 90 ), and mode diameter (D m ) is characterized by satisfying the following formulas (1) to (3): D 90 / D 10 >10... Equation (1) D 50 <1μm... Formula (2) D m <2μm...Equation (3) [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a liquid composition that has good ejection properties in an inkjet system and that can provide a solid electrolyte layer with good ion conductivity. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing an example of a solid electrolyte layer or electrode mixture layer manufacturing apparatus for realizing the method for manufacturing a solid electrolyte layer or an electrode mixture layer according to this embodiment. [Figure 2] FIG. 2 is a schematic diagram showing another example of a solid electrolyte layer or electrode mixture layer manufacturing apparatus (liquid ejection apparatus) for realizing the method for manufacturing a solid electrolyte layer or an electrode mixture layer according to this embodiment. [Figure 3] FIG. 3 is a schematic diagram showing an example of an energy storage element provided with a solid electrolyte layer of this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] (liquid composition) One embodiment of the liquid composition of the present invention comprises a solvent, an inorganic solid electrolyte, a dispersant, and optionally further comprises other components (hereinafter, this may be referred to as the "first embodiment"). Another embodiment of the liquid composition of the present invention is a liquid composition ejected using an inkjet head, comprising a solvent, an inorganic solid electrolyte, a dispersant, and optionally further comprises other components (hereinafter, this may be referred to as the "second embodiment").

[0010] As described above, the solid electrolyte layer of an all-solid-state battery is required to have high Li-ion conductivity. From the viewpoint of productivity, the method for producing the solid electrolyte layer is preferably a wet coating process using a die coater, a comma coater, or the like, and further, from the viewpoint of on-demand, it is considered preferable to form the solid electrolyte by inkjet ejection using a liquid ejection device.

[0011] However, it has been extremely difficult to obtain a liquid composition that can provide a solid electrolyte layer with good ionic conductivity while maintaining good inkjet ejection properties. For example, using large particles of the solid electrolyte material in the liquid composition is preferable because it can suppress grain boundary resistance and maintain good ionic conductivity, but it leads to a decrease in inkjet ejection properties. On the other hand, using small particles of the solid electrolyte material in the liquid composition allows stable ejection using the inkjet method, but the increase in the number of grain boundaries increases grain boundary resistance, leading to a decrease in ionic conductivity.

[0012] The present inventors have developed a liquid composition comprising a solvent, an inorganic solid electrolyte (hereinafter sometimes referred to as an "ion-conductive material"), and a dispersant, wherein the dispersant is soluble in the solvent, and the particle diameter at 10% volume fraction of the solid content contained in the liquid composition (D 10 ), volume fraction 50% particle diameter (D 50 ), volume fraction 90% particle diameter (D 90 ), and mode diameter (D m) satisfies the following formulae (1) to (3), it has been found that a liquid composition can be obtained which has good ejection properties in an inkjet system and is capable of forming a solid electrolyte layer with good ion conductivity. D 90 / D 10 >10... Equation (1) D 50 <1μm... Formula (2) D m <2μm...Equation (3)

[0013] This can be explained for the following reasons. In actual powder packing of a liquid composition during drying, particles are thought to be packed randomly. In the case of ideal close packing, i.e., when small particles fill the gaps between larger particles, it is necessary for small particles to fill the gaps between larger particles, but this situation is difficult to achieve with random packing. In fact, the effects of defects appear in areas where large particles do not exist, resulting in a decrease in ionic conductivity. Therefore, extremely high pressures of 100 MPa or more are required to increase the packing density. In such a situation, it was found that a situation in which particles having a wide range of particle sizes are continuously present and, contrary to the case of ideal packing, there are many small particles present, actually improves the packing rate of the solid electrolyte membrane of dry powder obtained from the liquid composition and works favorably in terms of ionic conductivity.

[0014] In this specification, "ejectable by inkjet method" refers to a case where ejection is performed from one nozzle (nozzle diameter: 40 μm) of an inkjet head using a droplet observation device EV1000 (manufactured by Ricoh Co., Ltd.) and the ejection state can be maintained for 60 seconds or more. Note that "the ejection state can be maintained for 60 seconds or more" means that the liquid composition has been ejected for at least 60 seconds from the start of ejection, regardless of the amount of ejection. In other words, as long as the liquid composition has been ejected for at least 60 seconds from the start of ejection, the amount of ejection may or may not change between the start of ejection and the 60 seconds after the start of ejection.

[0015] <Solvent> -First aspect- The solvent in the first aspect is not particularly limited and can be appropriately selected depending on the purpose, but a solvent having a relative dielectric constant of 6.0 or less at 25°C is preferred. The preferred solvent is advantageous in that it can improve the dispersibility of the inorganic solid electrolyte in the solvent, whether it is an inorganic solid electrolyte containing elemental sulfur or an inorganic solid electrolyte containing elemental oxygen. Furthermore, when the preferred solvent is used in combination with an inorganic solid electrolyte containing elemental sulfur, it is advantageous in that it makes it difficult for the solvent to react with the inorganic solid electrolyte containing elemental sulfur, thereby suppressing the generation of toxic hydrogen sulfide. The solvent may be used alone, or two or more types may be used in combination. When a mixed solvent containing two or more solvents is used, it is preferable that the mixed solvent has a relative dielectric constant of 6.0 or less.

[0016] The method for measuring the relative dielectric constant of the solvent is not particularly limited and can be appropriately selected depending on the purpose. For example, the relative dielectric constant can be measured by performing a double-cylinder tube current measurement at 10 kHz using Model 871 (manufactured by Sanyo Trading Co., Ltd.).

[0017] Specific examples of the solvent having a relative dielectric constant at 25°C of 6.0 or less include pentane, isopentane, hexane, heptane, 2,2-dimethylbutane, octane, cyclohexane, tetradecane, 1,4-dioxane, benzene, xylene, carbon tetrachloride, mesitylene, toluene, dibutyl ether, anisole, 1,2-diethoxyethane, 2-methylanisole, 3-methylanisole, 4-methylanisole, 1,2-methoxybenzene, 1,3-methoxybenzene, p-ethylaniline, 4-octanol, phenetole, 2-ethylhexyl acetate, butylphenyl ether, isopropylbenzene, 1,2,3,4-tetrahydronaphthalene, ethyl decanoate, isobutyl acetate, diisopentyl ether, tridecane, cyclooctane, and ethyl propionate.

[0018] The solvent is preferably dehydrated. The degree of dehydration is not particularly limited and can be appropriately selected depending on the purpose, but the water content measured with a Karl Fischer moisture content meter is preferably 1,000 ppm or less, more preferably 100 ppm or less, and even more preferably 10 ppm or less.

[0019] -Second aspect- The solvent in the second embodiment is the same as the solvent in the first embodiment.

[0020] <Inorganic solid electrolyte> -First aspect- The inorganic solid electrolyte in the first embodiment is not particularly limited as long as it has ionic conductivity but not electronic conductivity. Among the inorganic solid electrolytes, sulfide solid electrolytes containing sulfur element in the composition formula or oxide solid electrolytes containing oxygen element as an anion are preferred from the viewpoint of ionic conductivity, and sulfide solid electrolytes are more preferred because they have high plasticity and can form good interfaces between solid electrolyte particles or between the solid electrolyte and the active material. The inorganic solid electrolyte may be one type or two or more types, and can be used as appropriate.

[0021] --Sulfide solid electrolyte-- The sulfide solid electrolyte can be roughly divided into a crystalline sulfide solid electrolyte and a glass solid electrolyte. The crystalline sulfide solid electrolyte is not particularly limited and can be appropriately selected depending on the purpose. For example, 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 , Li10 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 and M2 are Si, Ge, Sn, As, and 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 is any of Cl, Br, and I), Li5PS4X2 (X is any of Cl, Br, and 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 is any of Si, Ge, and Sn, 0≦x≦1), Li7P2S8I, γ-Li3PS4, Li4MS4 (M is any of Ge, Sn, and As), Li 4-x Sn 1-x Sb x S4(0≦x≦0.15), Li 4-x Ge 1-x P x S4(0≦x≦0.15), Li 3+5x P 1-x Examples include S4 (0≦x≦0.3). The glass-based sulfide solid electrolyte is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof 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 MOy (M is Si, P, or Ge). Also, Li7P3S, which is a glass-based sulfide solid electrolyte partially crystallized, is used. 11 Glass ceramics can also be used. Here, the mixing ratio of the raw materials of the glass-based sulfide solid electrolyte is not important.

[0022] --Oxide solid electrolyte-- The oxide-based inorganic solid electrolyte is preferably a compound that contains oxygen element (O), has the ionic conductivity of a metal belonging to Group 1 or 2 of the periodic table, and has electronic insulation properties.

[0023] The oxide solid electrolytes can be roughly divided into crystalline oxide solid electrolytes and glass oxide solid electrolytes. The crystalline oxide solid electrolyte is not particularly limited and can be appropriately selected depending on the purpose. For example, Li 1+x M x Ti 2-x (PO4)3 (M is Al, Cr, Ga, Fe, Sc, In, Lu, Y, or La, 0≦x≦0.5), La x Li y TiO3(0.3≦x≦0.7, 0.3≦y≦0.7), Li 7-x La3Zr 2-x M x O 12 (M is either Nb or Ta, 0≦x≦1). The glass-based oxide solid electrolyte is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include Li4SiO4-Li2BO3, Li3BO3-Li2SO4, Li2O-B2O3-P2O5, and Li2O-SiO2.

[0024] The inorganic solid electrolyte may be prepared by a known method or may be a commercially available product.

[0025] The content of the inorganic solid electrolyte in the liquid composition is not particularly limited and can be appropriately selected depending on the purpose, but the solid content concentration of the inorganic solid electrolyte is preferably 10% by mass or more, more preferably 15% by mass or more, and particularly preferably 30% by mass or more. The upper limit is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 60% by mass or less. A content within the above preferred range is advantageous in terms of better productivity.

[0026] -Second aspect- The inorganic solid electrolyte in the second embodiment is the same as the inorganic solid electrolyte in the first embodiment.

[0027] <Dispersant> -First aspect- The dispersant in the first aspect is not particularly limited as long as it dissolves in the solvent, does not react easily with the inorganic solid electrolyte, and can disperse the inorganic solid electrolyte, and conventionally known or commercially available dispersants can be appropriately selected depending on the purpose. The dispersant may be used alone or in combination of two or more.

[0028] In this specification, the dispersant being dissolved in the solvent means that the dispersant is compatible with the solvent. More specifically, when 3% by mass of the dispersant is added to the solvent, the dispersant is dissolved, and the solution is allowed to stand for 10 minutes. If no precipitate or supernatant is observed, the dispersant can be determined to be dissolved.

[0029] Specific examples of the dispersant include polymer dispersants such as polyethylene-based, polyethylene oxide-based, polypropylene oxide-based, polycarboxylic acid-based, naphthalenesulfonic acid-formalin condensation-based, polyethylene glycol-based, polycarboxylic acid partial alkyl ester-based, polyether-based, polyethyleneimine-based, and polyalkylene polyamine-based; low molecular weight dispersants such as alkyl sulfonic acid-based, quaternary ammonium-based, higher alcohol alkylene oxide-based, polyhydric alcohol ester-based, and alkyl polyamine-based; and inorganic dispersants such as polyphosphate dispersants.

[0030] The content of the dispersant in the liquid composition is not particularly limited and can be appropriately selected depending on the purpose, but the solid content concentration of the dispersant is preferably 10% by mass or less, more preferably 3% by mass or less, based on the solid electrolyte to be dispersed. If the dispersant concentration is outside the preferred range, there is a concern that aggregation may occur due to excessively high dispersant concentration.

[0031] -Second aspect- The dispersant in the second embodiment is the same as the dispersant in the first embodiment.

[0032] <Other ingredients> The other components in the liquid compositions of the first and second embodiments 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. Examples include known components used in solid electrolyte layers or electrode mixture layers. Specific examples include binders, active materials, and conductive additives. These may be used alone or in combination of two or more. The content of the other components in the liquid composition is not particularly limited and can be appropriately selected depending on the purpose.

[0033] -binder- The binder is not particularly limited as long as it can bind the inorganic solid electrolytes together or the inorganic solid electrolyte to the substrate or the electrode active material, and can be appropriately selected depending on the purpose, and examples thereof include polymer compounds, polymer particles, etc. These may be used alone or in combination of two or more.

[0034] The polymer compound is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include polyamide compounds, polyimide compounds, polyamideimide, ethylene-propylene-butadiene rubber (EPBR), styrene-butadiene rubber (SBR), nitrile butadiene rubber (NBR), isoprene rubber, polyisobutene, polyethylene glycol (PEO), polymethyl methacrylic acid (PMMA), and polyethylene vinyl acetate (PEVA).

[0035] Polymer particles may be used as the polymer compound dispersible in liquid. The maximum particle diameter of the polymer particles may be smaller than the nozzle diameter of the liquid ejection head. The mode diameter of the polymer particles is preferably 0.01 to 1 μm. Examples of materials constituting the polymer particles include thermoplastic resins such as polyvinylidene fluoride, acrylic resin, styrene-butadiene rubber, polyethylene, polypropylene, polyurethane, nylon, polytetrafluoroethylene, polyphenylene sulfide, polyethylene terephthalate, and polybutylene terephthalate.

[0036] -Active material- As the active material, a positive electrode active material or a negative electrode active material that can be applied to an electrochemical element can be used.

[0037] The positive electrode active material is not particularly limited as long as it is capable of reversibly absorbing and releasing alkali metal ions, and an alkali metal-containing transition metal compound can be used.

[0038] Examples of the alkali metal-containing transition metal compound 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.

[0039] Examples of the lithium-containing transition metal compound include lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, and lithium nickel cobalt manganese oxide.

[0040] The alkali metal-containing transition metal compound may also be a polyanionic compound having an XO4 tetrahedron (X=P, S, As, Mo, W, Si, etc.) in its crystal structure. Among these, lithium-containing transition metal phosphate compounds such as lithium iron phosphate and lithium vanadium phosphate are preferred in terms of cycle characteristics, and lithium vanadium phosphate is particularly preferred in terms of lithium diffusion coefficient and input / output characteristics of electrochemical devices.

[0041] From the viewpoint of electron conductivity, the polyanionic compound is preferably composited by coating the surface with a conductive aid such as a carbon material.

[0042] The negative electrode active material is not particularly limited as long as it is capable of reversibly absorbing and releasing alkali metal ions, but carbon materials containing graphite having a graphite-type crystal structure can be used.

[0043] Examples of the carbon material include natural graphite, artificial graphite, non-graphitizable carbon (hard carbon), and easily graphitizable carbon (soft carbon).

[0044] Examples of the negative electrode active material other than the carbon material include lithium titanate and titanium oxide.

[0045] In terms of the energy density of the electrochemical device, it is preferable to use, as the negative electrode active material, a high-capacity material such as metallic lithium, silicon, tin, a silicon alloy, a tin alloy, silicon oxide, silicon nitride, or tin oxide.

[0046] The content of the active material in the liquid composition is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10% by mass or more, more preferably 15% by mass or more. When the content of the active material in the liquid composition is 10% by mass or more, the number of printing operations required to form an electrode mixture layer with a predetermined basis weight is reduced.

[0047] -Conductive additive- The conductive assistant is not particularly limited and can be appropriately selected depending on the purpose. For example, carbon materials such as conductive carbon black, carbon nanofibers, carbon nanotubes, graphene, and graphite particles can be used. Here, the conductive additive may be compounded with the active material.

[0048] The conductive carbon black can be produced by, for example, a furnace method, an acetylene method, a gasification method, or the like.

[0049] As the conductive additive other than the carbon material, for example, metal particles such as aluminum particles and metal fibers can be used.

[0050] The amount of the conductive additive relative to the active material is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10% by mass or less, more preferably 8% by mass or less.

[0051] [Particle size, particle size distribution] The solid components, such as the solid electrolyte and other solid components added as needed, contained in the liquid compositions of the first and second embodiments have a particle diameter (D 10 ), volume fraction 50% particle diameter (D 50 ), volume fraction 90% particle diameter (D 90 ), and mode diameter (D m ) satisfies the following formulae (1) to (3): When the following formulae (1) to (3) are satisfied, the ionic conductivity of the dried material obtained from the liquid composition can be improved. D 90 / D 10 >10... Equation (1) D 50 <1μm... Formula (2) D m <2μm...Equation (3)

[0052] The above D 90 / D 10is not particularly limited as long as it is more than 10 and can be appropriately selected depending on the purpose, but is preferably 15 or more, more preferably 20 or more, in terms of better ionic conductivity.

[0053] The above D 10 The diameter is not particularly limited as long as it satisfies the above formula (1) and can be appropriately selected depending on the purpose, but is preferably 1 μm or less, more preferably 0.5 μm or less, in terms of excellent ion conductivity. 10 The lower limit is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.05 μm or more.

[0054] The above D 90 The diameter is not particularly limited as long as it satisfies the above formula (1) and can be appropriately selected depending on the purpose, but is preferably 2 μm or more, more preferably 4 μm or more, in terms of excellent ion conductivity. 90 There is no particular upper limit to the thickness, which can be selected appropriately depending on the purpose, but it is preferably 10 μm or less.

[0055] The above D 50 The diameter of the porous film is not particularly limited as long as it satisfies the formula (2) and can be appropriately selected depending on the purpose, but it is preferably 1.0 μm or less in terms of superior ion conductivity. 50 The lower limit is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.5 μm or more.

[0056] The above D m The diameter is not particularly limited as long as it satisfies the formula (3) and can be appropriately selected depending on the purpose, but is preferably 2 μm or less, more preferably 1.5 μm or less, in terms of better ion conductivity. m The lower limit is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.5 μm or more.

[0057] [Maximum particle size] The maximum particle size of the solid content contained in the liquid composition of the first and second embodiments is not particularly limited as long as it does not impair the effects of the present invention and can be appropriately selected depending on the purpose. However, it is preferably smaller than the nozzle diameter of the inkjet head, and is preferably sufficiently smaller than the nozzle diameter of the inkjet head in order to further improve inkjet ejection properties. Specifically, the ratio of the maximum particle size of the solid content contained in the liquid composition to the nozzle diameter of the inkjet head (maximum particle size of the solid content contained in the liquid composition / nozzle diameter of the inkjet head) is preferably 0.8 or less, more preferably 0.6 or less, and even more preferably 0.5 or less. That is, if the nozzle diameter of the inkjet head is 40 μm, the maximum particle size of the solid content contained in the liquid composition is preferably 32 μm or less, more preferably 24 μm or less, and even more preferably 20 μm or less.

[0058] D of the solid content contained in the liquid composition 10 , D 50 , D 90 , D m The method for measuring the particle size and maximum particle diameter is not particularly limited and can be appropriately selected depending on the purpose, and can be measured, for example, in accordance with ISO 13320. 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 / scattering particle size distribution analyzer (LA-960, manufactured by Horiba, Ltd.).

[0059] The method for measuring the maximum particle size of the powder components used as raw materials for the liquid composition is not particularly limited and can be appropriately selected depending on the purpose. Examples include a method for measuring the maximum particle size using laser diffraction, a method for determining the maximum particle size from an image obtained by scanning electron diffraction, and the like, similar to the method for measuring the maximum particle size of the solid content contained in the liquid composition described above.

[0060] [viscosity] The viscosity of the liquid composition of the first and second aspects is not particularly limited as long as it does not impair the effects of the present invention and can be appropriately selected depending on the purpose, but it is preferably a viscosity that allows it to be ejected from the nozzles of an inkjet head. More specifically, the viscosity at 25°C is preferably 200 mPa·s or less, more preferably 100 mPa·s or less, even more preferably 50 mPa·s or less, and particularly preferably 25 mPa·s or less. The lower limit is not particularly limited, but may be appropriately set so as to allow ejection by an inkjet method.

[0061] The method for measuring the viscosity of the liquid composition is not particularly limited and can be appropriately selected depending on the purpose. For example, the viscosity can be measured using a B-type viscometer (cone-plate viscometer) equipped with a No. CPA-40Z rotor. In this specification, the viscosity of the liquid composition refers to the viscosity at 25°C.

[0062] The method for producing the liquid composition is not particularly limited and can be appropriately selected depending on the purpose, but it is preferable to produce the liquid composition by the method for producing the liquid composition of the present invention described below.

[0063] The use of the liquid composition is not particularly limited and can be appropriately selected depending on the purpose, but it can be suitably used as a material for a solid electrolyte layer of an all-solid-state secondary battery or as a part when forming a material for an electrode mixture layer.

[0064] (Method of producing liquid composition) The method for producing the liquid composition of the present invention is a method for producing the above-described liquid composition of the present invention, and includes a dissolving or dispersing step, and may further include other steps as necessary.

[0065] <Dissolution or dispersion process> The dissolving or dispersing step is a step of dissolving or dispersing an inorganic solid electrolyte and a dispersant that dissolves in the solvent in a solvent. For example, the inorganic solid electrolyte, the dispersant, and, if necessary, the other components can be added to the solvent and mixed to prepare the dispersion. The solvent, the inorganic solid electrolyte, and the dispersant are the same as the solvent, the inorganic solid electrolyte, and the dispersant described in the liquid composition section above. The mixing means is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include an ultrasonic homogenizer, etc. The mixing conditions are not particularly limited and can be appropriately selected depending on the purpose.

[0066] <Other processes> The other steps are not particularly limited as long as they do not impair the effects of the present invention, and can be appropriately selected depending on the purpose. For example, an adjustment step can be mentioned.

[0067] -Adjustment process- The adjusting step is a step of adjusting the particle size of the solid content in the liquid composition by mechanical treatment. The means for the mechanical treatment is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include means selected from a high-speed rotation homogenizer, a wet jet mill, a wet bead mill, and a combination of two or more of these. The conditions for the mechanical treatment are not particularly limited and can be appropriately selected depending on the purpose. The adjusting step may be carried out during the dissolving or dispersing step, or may be carried out after the dissolving or dispersing step. The adjusting step allows the solid content contained in the liquid composition to satisfy the above formulas (1) to (3). Note that if the dissolving or dispersing step is carried out using a liquid composition whose solid content satisfies the above formulas (1) to (3), the adjusting step does not need to be carried out.

[0068] (container) The storage container of the present invention is a storage container that stores the above-described liquid composition of the present invention. The shape, structure, and size of the container are not particularly limited and can be appropriately selected depending on the purpose.

[0069] (Production apparatus for solid electrolyte layer or electrode mixture layer, production method for solid electrolyte layer or electrode mixture layer) The manufacturing apparatus for a solid electrolyte layer or an electrode mixture layer of the present invention includes the above-described storage container of the present invention and a discharge means that discharges the liquid composition stored in the storage container using an inkjet head, and may further include other components as necessary. The method for producing a solid electrolyte layer or an electrode mixture layer of the present invention includes a discharge step of discharging the above-described liquid composition of the present invention using an inkjet head, and may further include other steps as necessary.

[0070] <Discharge means, discharge process> The ejection means is a means for ejecting the liquid composition contained in the container using an inkjet head. The ejection step is a step of ejecting the liquid composition using an inkjet head. By discharging the liquid composition, it is possible to apply the liquid composition onto an object and form a liquid composition layer. The target object (hereinafter sometimes referred to as "discharge target object") is not particularly limited as long as it is an object on which a solid electrolyte layer or an electrode mixture layer is to be formed, and can be appropriately selected depending on the purpose, and examples thereof include an active material layer.

[0071] <Other components and processes> Other components of the manufacturing apparatus for the solid electrolyte layer or electrode mixture layer are not particularly limited as long as they do not impair the effects of the present invention, and can be appropriately selected depending on the purpose. For example, a heating means may be used. Other steps in the method for producing the solid electrolyte layer or the electrode mixture layer are not particularly limited as long as they do not impair the effects of the present invention, and can be appropriately selected depending on the purpose. For example, a heating step can be included.

[0072] -Heating means, heating process- The heating means is a means for heating the liquid composition ejected by the ejection means. The heating step is a step of heating the liquid composition ejected in the ejection step. The heating can dry the liquid composition layer.

[0073] FIG. 1 is a schematic diagram showing an example of a solid electrolyte layer or electrode mixture layer manufacturing apparatus for realizing the method for manufacturing a solid electrolyte layer or an electrode mixture layer according to this embodiment.

[0074] The solid electrolyte layer or electrode mixture layer manufacturing apparatus of Figure 1 is an apparatus for manufacturing a solid electrolyte layer or an electrode mixture layer using the above-mentioned liquid composition. The solid electrolyte layer or electrode mixture layer apparatus includes a discharge process unit 10 that includes a process of applying a liquid composition to a printing substrate 4 having a discharge target to form a liquid composition layer, and a heating process unit 30 that includes a heating process of heating the liquid composition layer to obtain a solid electrolyte layer or an electrode mixture layer. The solid electrolyte layer or electrode mixture layer apparatus includes a conveying unit 5 that conveys the printing substrate 4, and the conveying unit 5 conveys the printing substrate 4 at a predetermined speed from the discharge process unit 10 to the heating process unit 30 in that order. The method for producing the printing substrate 4 having the discharge target such as the active material layer is not particularly limited, and any known method can be appropriately selected.

[0075] The ejection process section 10 includes an optional printing device 1a suitable for inkjet printing, which is an application means for realizing the application process of applying a liquid composition onto a printing substrate 4, a storage container 1b for storing the liquid composition, and a supply tube 1c for supplying the liquid composition stored in the storage container 1b to the printing device 1a.

[0076] The storage container 1b stores a liquid composition 7, and the discharge process unit 10 discharges the liquid composition 7 from the printing device 1a and applies the liquid composition 7 onto the printing substrate 4 to form a thin film of the liquid composition layer. The storage container 1b may be configured as an integral part of the solid electrolyte layer or electrode mixture layer device, or may be configured as a removable device from the solid electrolyte layer or electrode mixture layer device. Alternatively, the storage container 1b may be a container used for adding to a storage container integrated with the solid electrolyte layer or electrode mixture layer device or a storage container removable from the solid electrolyte layer or electrode mixture layer device.

[0077] The storage container 1b and the supply tube 1c can be arbitrarily selected as long as they can stably store and supply the liquid composition 7.

[0078] As shown in Fig. 1, the heating process section 30 has a heating device 3a and includes a solvent removal step in which the solvent remaining in the liquid composition layer is heated and dried using the heating device 3a to remove it. This allows a solid electrolyte layer or an electrode mixture layer to be formed. The heating process section 30 may perform the solvent removal step under reduced pressure.

[0079] The heating device 3a is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include a substrate heater, an IR heater, and a hot air heater, and these may be combined.

[0080] The heating temperature and time can be appropriately selected depending on the boiling point of the solvent contained in the liquid composition 7 and the thickness of the formed film.

[0081] FIG. 2 is a schematic diagram showing another example of a solid electrolyte layer or electrode mixture layer manufacturing apparatus (liquid ejection apparatus) for realizing the method for manufacturing a solid electrolyte layer or an electrode mixture layer according to this embodiment.

[0082] The liquid ejection device 300 ′ is capable of circulating the liquid composition through the liquid ejection head 306 , the tank 307 and the tube 308 by controlling the pump 310 and the valves 311 and 312 .

[0083] In addition, the liquid ejection device 300' is provided with an external tank 313, and when the liquid composition in the 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.

[0084] By using the solid electrolyte layer or electrode mixture layer manufacturing device, the liquid composition can be ejected onto a target object.

[0085] The solid electrolyte layer or the electrode mixture layer can be suitably used as, for example, a part of the configuration of an energy storage element. The components of the energy storage element other than the solid electrolyte layer or the electrode mixture layer are not particularly limited and can be appropriately selected from known components, such as a positive electrode, a negative electrode, and a separator.

[0086] As a method for producing the electric storage element, any known method can be appropriately selected, except that the solid electrolyte layer or the electrode mixture layer is that of the present invention.

[0087] The shape of the energy storage element is not particularly limited and can be selected appropriately depending on the purpose, and can be selected appropriately depending on the application from various commonly used shapes, such as the shape shown in Fig. 3. The shape is not particularly limited and can be selected appropriately depending on the purpose, and examples include a cylindrical type in which a sheet electrode and a solid electrolyte layer are spirally wound, a cylindrical type with an inside-out structure combining a pellet electrode and a solid electrolyte layer, and a coin type in which a pellet electrode and a solid electrolyte layer are stacked.

[0088] FIG. 3 is a schematic diagram showing an example of an energy storage element provided with a solid electrolyte layer of this embodiment. As shown in FIG. 3, the energy storage element 110 according to this embodiment has a positive electrode 11, a negative electrode 12 disposed opposite the positive electrode 11, and a solid electrolyte layer 13 disposed between the positive electrode 11 and the negative electrode 12. The energy storage element 110 has a container 15 as an outer can that surrounds and holds the positive electrode 11, the negative electrode 12, and the electrolyte layer 13, a positive electrode wire 16 that passes through the container 15 and is connected to the positive electrode 11, and a negative electrode wire 17 that similarly passes through the container 15 and is connected to the negative electrode 12.

[0089] <Application> The use of the energy storage element is not particularly limited, and the energy storage element can be used for various purposes. Examples include power sources and backup power sources for 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 machines, liquid crystal televisions, handheld cleaners, portable CDs, minidiscs, transceivers, electronic organizers, calculators, memory cards, portable tape recorders, radios, motors, lighting equipment, toys, game machines, clocks, strobes, cameras, etc. [Example]

[0090] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples. Unless otherwise specified, the following operations were carried out in an argon glove box maintained at a dew point of −70° C. or less in order to suppress reaction between the inorganic solid electrolyte and moisture in the air.

[0091] The ionic conductivity, particle size, and particle size distribution in the Preparation Examples, Examples, and Comparative Examples described below were measured as follows.

[0092] [Measurement of ionic conductivity] First, 30 mg of the powder was placed in a 2.5 mm diameter press jig and pressed at 10 MPa using a uniaxial hydraulic press to form a pellet. Gold powder was then added to the top and bottom surfaces of the pellet, and the electrode was formed by pressing at 1 MPa. The ionic conductivity (S / cm) was calculated by an AC impedance method in a thermostatic bath at 30°C. The ionic conductivity was evaluated according to the following criteria. ○: Excellent ionic conductivity (ionic conductivity is 1×10 -4 S / cm or more.) ×: Poor ionic conductivity (ionic conductivity is less than 1×10 -4 S / cm or less.)

[0093] [Method for measuring particle size and particle size distribution] D of solids contained in the liquid composition 10 , D 50 , D 90 , D m and maximum particle size were determined in accordance with ISO13320 as follows. First, the liquid composition was diluted with the same solvent as used so that the solid content concentration was 0.1 to 10 ppm to prepare a diluted solution. The diluted solution was placed in a quartz glass container and sealed with a packing. Next, the quartz glass container sealed with a packing was taken out of the glove box, and the D 10 , D 50 , D 90 , D m The dilution concentration was adjusted with the same solvent as that used in the liquid composition so that the transmitted light intensity measured by the laser diffraction / scattering particle size distribution analyzer was within an appropriate range.

[0094] (Preparation Examples 1 to 4: Synthesis of Inorganic Solid Electrolytes 1 to 4) Argyrodite-type sulfide solid electrolytes (Li6PS5Cl) with different particle sizes were prepared as inorganic solid electrolytes 1 to 4 according to the literature 1 (H.-J. Deiseroth, S.-T. Kong, H. Eckert, J. Vannahme, C. Reiner, T. Zaiss and M. Schlosser, Angew. Chem., Int. Ed. 47, 755(2008)). The ionic conductivity of the inorganic solid electrolytes of Preparation Examples 1 to 4 was measured as described above. 10 , D 50 , D 90 , and D m The results are shown in Table 1.

[0095] [Table 1]

[0096] (Examples 1 to 2 and Comparative Examples 1 to 3: Preparation of liquid compositions and dry powders) [Preparation of Liquid Composition] In the following Examples 1 and 2 and Comparative Examples 1 to 3, liquid compositions were prepared as follows. An inorganic solid electrolyte and a dispersant (S21000, manufactured by Lubrizol) were added to a solvent. The inorganic solid electrolyte was added to the solvent so that the content of the inorganic solid electrolyte was 20% by mass relative to the liquid composition. The dispersant was added in a mass ratio of 1% by mass relative to the inorganic solid electrolyte. Here, the dehydrated solvent used was confirmed to have a water content of 100 ppm or less using a Karl Fischer moisture content meter.

[0097] [Preparation of dry powder] The obtained liquid composition was dropped into an evaporating dish and heated on a hot plate maintained at 120° C. for 1 hour to obtain a dry powder.

[0098] For the liquid compositions of Examples 1 and 2 and Comparative Examples 1 to 3 below, the ionic conductivity, particle size and particle size distribution were measured as described above, and the viscosity and inkjet dischargeability of the liquid compositions were evaluated as follows.

[0099] [Viscosity of liquid composition] A No. CPA-40Z rotor was attached to a Brookfield viscometer (cone-plate type viscometer) and the viscosity of the liquid composition at 100 rpm was measured at 25°C.

[0100] [Inkjet ejection properties] The ink jet ejection properties of the liquid composition were evaluated using a droplet observation device EV1000 (manufactured by Ricoh Co., Ltd.) as follows. The liquid composition to be evaluated was ejected from one nozzle (nozzle diameter: 40 μm) of an inkjet head using an EV1000, and if the ejection state could be maintained for 60 seconds or more, it was determined to be ejectable. Note that, if the ejection state could be maintained for 60 seconds or more, this means that the liquid composition has been ejected for at least 60 seconds from the start of ejection, regardless of the amount of ejection. In other words, as long as the liquid composition has been ejected for at least 60 seconds from the start of ejection, the amount of ejection may or may not change between the start of ejection and the 60 seconds after the start of ejection. -evaluation- ○: Discharge possible (discharge state can be maintained for 60 seconds or more) ×: Not possible to discharge (cannot maintain discharge state for 60 seconds)

[0101] Example 1: Liquid composition A and its dry powder The solid electrolyte 4 and the dispersant were added to octane (dielectric constant 2.1, manufactured by Tokyo Chemical Industry Co., Ltd.), and the mixture was treated for 1 hour at a rotation speed of 30,000 rpm using a high-speed rotary homogenizer (manufactured by Kinematica, MT3100S2) to prepare liquid composition A. D of the solid content contained in liquid composition A determined by laser diffraction method 10 , D 50 , D 90 , D m , and the maximum particle sizes were 0.12 μm, 0.8 μm, 2.1 μm, 1.2 μm, and 5.0 μm, respectively. The viscosity of the resulting liquid composition A was 8 mPa·s. The ionic conductivity of the dry powder obtained from liquid composition A was 1.0 × 10 -3 It was S / cm. Furthermore, the inkjet ejection properties of the obtained liquid composition A were examined using EV1000, and it was confirmed that continuous ejection for 60 seconds was possible.

[0102] Example 2: Liquid Composition B and its Dry Powder 10 mass % of the solid electrolyte 1, 7 mass % of the solid electrolyte 2, and 3 mass % of the solid electrolyte 3, as well as the dispersant, were added to octane (dielectric constant: 2.1, manufactured by Tokyo Chemical Industry Co., Ltd.), and the mixture was treated with an ultrasonic homogenizer (manufactured by Nippon Seiki Seisakusho Co., Ltd., US-300E) at 500 W for 10 minutes to prepare a liquid composition B. D of the solid content contained in liquid composition B determined by laser diffraction method 10 , D 50 , D 90 , D m , and the maximum particle sizes were 0.25 μm, 0.9 μm, 5.0 μm, 1.8 μm, and 7.0 μm, respectively. The viscosity of the resulting liquid composition B was 10 mPa·s. The ionic conductivity of the dry powder obtained from liquid composition B was 7 × 10 -4 It was S / cm. Furthermore, the inkjet ejection properties of the obtained liquid composition B were examined using EV1000, and it was confirmed that continuous ejection for 60 seconds was possible.

[0103] Comparative Example 1: Liquid Composition C and its Dry Powder The solid electrolyte 2 and the dispersant were added to octane (dielectric constant 2.1, manufactured by Tokyo Chemical Industry Co., Ltd.), and the mixture was treated for 1 hour at a rotation speed of 30,000 rpm using a high-speed rotary homogenizer (manufactured by Kinematica, MT3100S2) to prepare liquid composition C. D of the solid content contained in liquid composition C determined by laser diffraction method 10 , D 50 , D 90 , D m , and the maximum particle sizes were 0.6 μm, 0.8 μm, 3.0 μm, 1.5 μm, and 4.5 μm, respectively. The viscosity of the resulting liquid composition C was 10 mPa·s. The ionic conductivity of the dry powder obtained from liquid composition C was 5 × 10 -5 The value was S / cm, which was poor. Furthermore, the inkjet ejection properties of the obtained liquid composition C were examined using EV1000, and it was confirmed that continuous ejection for 60 seconds was possible.

[0104] Comparative Example 2: Liquid Composition D and its Dry Powder 10% by mass of the solid electrolyte 1 and 10% by mass of the solid electrolyte 3, as well as the dispersant, were added to octane (dielectric constant 2.1, manufactured by Tokyo Chemical Industry Co., Ltd.), and the mixture was treated at 180 MPa using a wet jet mill (Starburst Minimo, manufactured by Sugino Machine Co., Ltd.) to prepare a liquid composition D. D of the solid content contained in the liquid composition D determined by laser diffraction method 10 , D 50 , D 90 , D m , and the maximum particle sizes were 0.2 μm, 1.1 μm, 6.5 μm, 1.9 μm, and 16.0 μm, respectively. The viscosity of the obtained liquid composition D was 8 mPa·s. The ionic conductivity of the dry powder obtained from liquid composition D was 7 × 10 -4 It was S / cm. Furthermore, the ink jet ejection properties of the obtained liquid composition D were examined using EV1000. Clogging occurred in the ejection, and continuous ejection for 60 seconds was not possible, resulting in poor performance.

[0105] Comparative Example 3: Liquid Composition E and its Dry Powder 15% by mass of the solid electrolyte 1, 5% by mass of the solid electrolyte 4, and the dispersant were added to octane (dielectric constant 2.1, manufactured by Tokyo Chemical Industry Co., Ltd.), and the mixture was treated with an ultrasonic homogenizer (manufactured by Nippon Seiki Seisakusho Co., Ltd., US-300E) at 500 W for 10 minutes to prepare a liquid composition E. D of the solid content contained in the liquid composition E determined by laser diffraction method 10 , D 50 , D 90 , D m , and the maximum particle diameters were 0.4 μm, 0.8 μm, 7.0 μm, 3.0 μm, and 19.0 μm, respectively. The viscosity of the resulting liquid composition E was 11 mPa·s. The ionic conductivity of the dry powder obtained from liquid composition E was 4 × 10 -4 It was S / cm. Furthermore, the ink jet ejection properties of the obtained liquid composition E were examined using EV1000. Clogging occurred in the ejection, and continuous ejection for 60 seconds was not possible, resulting in poor performance.

[0106] The results of the above-mentioned Examples and Comparative Examples are shown in Table 2 below.

[0107] [Table 2]

[0108] Examples of aspects according to this embodiment are as follows. <1> A liquid composition comprising a solvent, an inorganic solid electrolyte, and a dispersant, The dispersant is dissolved in the solvent, The particle size (D) of the 10% volume fraction of the solid content contained in the liquid composition measured by laser diffraction method 10 ), volume fraction 50% particle diameter (D 50 ), volume fraction 90% particle diameter (D 90 ), and mode diameter (D m ) is a liquid composition characterized by satisfying the following formulas (1) to (3): D 90 / D 10 >10... Equation (1) D 50 <1μm... Formula (2) D m <2μm...Equation (3) <2> The viscosity of the liquid composition is 200 mPa·s or less. <1> The liquid composition according to claim 1. <3> The liquid composition has a maximum particle size of 32 μm or less. <1> from <2> The liquid composition according to any one of the above items. <4> A liquid composition ejected using an inkjet head, the liquid composition includes a solvent, an inorganic solid electrolyte, and a dispersant; The dispersant is dissolved in the solvent, The particle size (D) of the 10% volume fraction of the solid content contained in the liquid composition measured by laser diffraction method10 ), volume fraction 50% particle diameter (D 50 ), volume fraction 90% particle diameter (D 90 ), and mode diameter (D m ) is a liquid composition characterized by satisfying the following formulas (1) to (3): D 90 / D 10 >10... Equation (1) D 50 <1μm... Formula (2) D m <2μm...Equation (3) <5> The viscosity of the liquid composition is such that it can be ejected from a nozzle of an inkjet head. <4> The liquid composition according to claim 1. <6> The liquid composition has a maximum particle diameter smaller than the nozzle diameter of an inkjet head. <4> from <5> The liquid composition according to any one of the above items. <7> the ratio of the maximum particle diameter of the solid content contained in the liquid composition to the nozzle diameter of the inkjet head is 0.8 or less; <4> from <6> The liquid composition according to any one of the above items. <8> The solvent has a relative dielectric constant of 6.0 or less at 25°C. <1> from <7> The liquid composition according to any one of the above items. <9> The solid content concentration of the inorganic solid electrolyte in the liquid composition is 15 mass % or more. <1> from <8> The liquid composition according to any one of the above items. <10> The aforementioned <1> from <9> A method for producing the liquid composition according to any one of the above, The method for producing a liquid composition includes a dissolving or dispersing step of dissolving or dispersing an inorganic solid electrolyte and a dispersant that dissolves in a solvent. <11> The method further comprises adjusting the particle size of the solid content in the liquid composition by mechanical treatment. <10> 1. A method for producing the liquid composition according to claim 1. <12> The mechanical treatment is carried out by a means selected from a high-speed rotation homogenizer, a wet jet mill, a wet bead mill, and a combination of two or more of these. <11> 1. A method for producing the liquid composition according to claim 1. <13> The aforementioned <1> from <9> The liquid composition according to any one of the above items is contained in a container. <14> The aforementioned <13> and a discharge means for discharging the liquid composition contained in the storage container using an inkjet head. <15> Using an inkjet head <1> from <9> 1. A method for producing a solid electrolyte layer or an electrode mixture layer, comprising the step of discharging the liquid composition according to any one of the above items.

[0109] The aforementioned <1> from <9> The liquid composition according to any one of <10> from <12> The method for producing a liquid composition according to any one of the <13> The storage container according to <14> 2. The apparatus for manufacturing a solid electrolyte layer or an electrode mixture layer according to claim 1, <15> According to the method for producing a solid electrolyte layer or an electrode mixture layer described above, the various problems encountered in the past can be solved and the object of the present invention can be achieved. [Explanation of symbols]

[0110] 1a Printing device 1b Containment vessel 1c Supply tube 3a Heating device 4 Printing base material 5. Conveyor 7 Liquid composition 10 Discharge process section 11 Positive electrode 12 Negative electrode 13 Solid electrolyte layer 15 Container 16 Positive wire 17 Negative wire 30 Heating process section 110 Energy storage element 300' liquid dispensing device 306 Liquid ejection head 307 Tank 308 Tube 310 Pump 311 Valve 312 Valve 313 External Tank 314 Valve [Prior art documents] [Patent documents]

[0111] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-157084

Claims

1. A liquid composition ejected using an inkjet head, comprising: the liquid composition includes a solvent, an inorganic solid electrolyte, and a dispersant; The dispersant is dissolved in the solvent, A liquid composition characterized in that the particle diameter (D 10 ), particle diameter (D 50 ), particle diameter (D 90 ) at 10% volume fraction, and mode diameter (D m ) of a solid content contained in the liquid composition measured by a laser diffraction method satisfy the following formulas (1) to (3): D 90 / D 10 >10... Formula (1) D 50 <1 μm... Formula (2) D m <2 μm... Formula (3)

2. A liquid composition according to claim 1, wherein the viscosity of the liquid composition is such that it can be ejected from the nozzle of an inkjet head.

3. A liquid composition according to claim 1, wherein the viscosity of the liquid composition at 25°C is 200 mPa·s or less.

4. A liquid composition described in any one of claims 1 to 3, wherein the maximum particle diameter of the solid content contained in the liquid composition is smaller than the nozzle diameter of the inkjet head.

5. A liquid composition described in any one of claims 1 to 3, wherein the maximum particle diameter of the solid content contained in the liquid composition is 32 μm or less.

6. A liquid composition described in any one of claims 1 to 5, wherein the ratio of the maximum particle diameter of the solid content contained in the liquid composition to the nozzle diameter of the inkjet head is 0.8 or less.

7. A liquid composition described in any one of claims 1 to 6, wherein the solvent has a relative dielectric constant of 6.0 or less at 25°C.

8. A liquid composition described in any one of claims 1 to 7, wherein the solid content concentration of the inorganic solid electrolyte in the liquid composition is 15 mass% or more.

9. A method for producing a liquid composition according to any one of claims 1 to 8, comprising: A method for producing a liquid composition, comprising a dissolving or dispersing step of dissolving or dispersing, in a solvent, an inorganic solid electrolyte and a dispersant that is soluble in the solvent.

10. A method for producing a liquid composition as described in claim 9, further comprising an adjustment step of adjusting the particle size of the solid content in the liquid composition by mechanical treatment.

11. A method for producing a liquid composition according to claim 10, wherein the mechanical treatment is carried out by a means selected from a high-speed rotary homogenizer, a wet jet mill, a wet bead mill, and a combination of two or more of these.

12. A storage container characterized by containing a liquid composition described in any one of claims 1 to 8.

13. A manufacturing apparatus for a solid electrolyte layer, comprising: a storage container as described in claim 12; and an ejection means for ejecting the liquid composition stored in the storage container using an inkjet head.

14. A method for producing a solid electrolyte layer, comprising the step of ejecting the liquid composition according to any one of claims 1 to 8 using an inkjet head.

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