Method for manufacturing quasi-solid-state battery

Abstract

This method for manufacturing a quasi-solid-state battery comprises: a step for forming an aggregate having a volume-average particle diameter of 10-500 μm and a specific surface area of 20 m2 / g to 25 m2 / g, the aggregate being composed of an electrode active material and an electroconductive assistant; a step for stirring the aggregate while heating the aggregate to 100-300°C under reduced pressure; a step for mixing the aggregate with an electrolytic solution to obtain an electrode material; and a step for providing the electrode material on a support to form an electrode layer.

Description

Quasi-solid battery manufacturing method

[0001] The present disclosure relates to a method for manufacturing a quasi-solid-state battery.

[0002] Quasi-solid-state batteries have the advantage that the electrode layer can be formed without a drying process by mixing the electrolyte with the electrode active material and conductive additive in advance.Furthermore, because they do not contain a large amount of binder, they can be said to be batteries with excellent recyclability.

[0003] Patent Document 1 discloses an electrochemical cell including a positive current collector having a first surface and a second surface, a semi-solid cathode disposed only on the first surface of the positive current collector, a negative current collector having a first surface and a second surface, a semi-solid anode disposed only on the first surface of the negative current collector, and a separator disposed between the first surface of the positive current collector and the first surface of the negative current collector.

[0004] U.S. Patent No. 5,949,999 discloses a method comprising continuously dispensing a semi-solid electrode slurry onto a current collector, separating the semi-solid electrode slurry into separate portions, and cutting the current collector to form finished electrodes.

[0005] Patent Document 3 discloses a method for producing a sheet-like electrode molded body, which includes a first step of preparing granules containing one or both of an electrode active material and a conductive additive, and a second step of obtaining a mixture of the electrode active material, the conductive additive, and an electrolyte solution using the granules prepared in the first step, and which forms an electrode material film containing the electrode active material, the conductive additive, and the electrolyte solution on a support.

[0006] Patent Document 4 discloses a lithium-ion battery anode comprising a negative electrode active material layer formed on a negative electrode current collector and made of a non-binding material containing negative electrode active material particles and a conductive additive, wherein the negative electrode active material particles contain silicon and / or silicon compound particles, the conductive additive is a conductive carbon filler in which the average value of the maximum Feret diameter of unit particles in a projected image of the conductive additive obtained by a method in accordance with JIS Z8827-1:2008 is 0.001 to 0.1 times the volume average particle diameter of the negative electrode active material particles, and the proportion of the conductive additive contained in the negative electrode active material layer is 5 to 25 wt % based on the total weight of the negative electrode active material particles and the conductive additive.

[0007] Patent Document 1: JP-T-2017-533548A Patent Document 2: JP-T-2021-530829A Patent Document 3: WO 2024 / 024737 Patent Document 4: JP-T-2017-533548A

[0008] The present inventors have put these prior arts into practice and discovered new problems. For example, in the case of film formation as described in Patent Document 1, the electrode material has low fluidity, making it difficult to quantitatively supply the material into a frame, and a uniform electrode layer cannot be obtained. Furthermore, even when pressed, it is difficult to spread the material according to the frame shape, resulting in a non-uniform electrode layer shape. Furthermore, in the nozzle supply method as described in Patent Document 2, the small amount of liquid component results in low wettability to the current collector, resulting in areas where the electrode material is not applied, resulting in poor electrode layer formation.

[0009] The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to provide a method for manufacturing a quasi-solid-state battery that is excellent in terms of continuous supply of an electrode material and suppression of coating defects.

[0010] The means for solving the above problems include the following aspects: <1> A porous carbon nanotube comprising an electrode active material and a conductive additive, having a volume average particle size of 10 μm to 500 μm and a specific surface area of ​​20 m ２ / g~25m ２ / g aggregates, stirring the aggregates while heating them to 100°C to 300°C under reduced pressure, mixing the aggregates with an electrolyte solution to obtain an electrode material, and applying the electrode material to a support to form an electrode layer. <2> The method for manufacturing a quasi-solid battery according to <1>, wherein the step of forming the aggregates comprises mixing and stirring an electrode active material and a conductive additive, granulating the mixture under a pressure of 20 kN / cm to 2,000 kN / cm, and then milling the mixture. <3> The method for manufacturing a quasi-solid battery according to <2>, wherein, in the step of forming the aggregates, the volume average particle size of the aggregates after milling is larger than the thickness of the electrode layer to be formed. <4> The method for manufacturing a quasi-solid battery according to any one of <1> to <3>, wherein the water content of the aggregates after the stirring step is 200 ppm or less. <5> The method for manufacturing a quasi-solid battery according to any one of <1> to <4>, wherein, in the step of forming the electrode layer, the electrode material is applied to a support while applying vibrations with an amplitude of 1 μm to 100 μm and a frequency of 5 kHz to 500 kHz. <6> The method for manufacturing a quasi-solid battery according to any one of <1> to <5>, wherein the electrode material does not contain a binder. <7> The method for manufacturing a quasi-solid battery according to any one of <1> to <6>, wherein the stirring step is carried out under a reduced pressure of 0.1 kPa to 10 kPa. <8> The method for manufacturing a quasi-solid battery according to any one of <1> to <7>, wherein the volume average particle size of the aggregates in the electrode layer is smaller than the volume average particle size of the aggregates in the stirring step.

[0011] According to the present disclosure, it is possible to provide a method for manufacturing a quasi-solid-state battery that is excellent in the ability to continuously supply an electrode material and in the ability to suppress coating defects.

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The present disclosure is not limited to the following embodiments and can be implemented with appropriate modifications within the scope of the object of the present disclosure. Components indicated by the same reference numerals in the drawings are the same components. Descriptions of duplicated components and reference numerals in the drawings may be omitted. The dimensional ratios in the drawings do not necessarily represent the actual dimensional ratios.

[0013] In the present disclosure, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the upper and lower limits. In the numerical ranges described in stages in the present disclosure, the upper or lower limit described in a certain numerical range may be replaced with the upper or lower limit of another staged numerical range. Furthermore, in the numerical ranges described in the present disclosure, the upper or lower limit described in a certain numerical range may be replaced with a value shown in the examples. In the present disclosure, the term "process" includes not only an independent process but also a process that cannot be clearly distinguished from other processes as long as the intended purpose of the process is achieved. In the present disclosure, "(meth)acrylic" means both acrylic and methacrylic, or either one. In the present disclosure, when multiple substances corresponding to each component are present in the composition, the amount of each component in the composition means the total amount of the multiple substances present in the composition, unless otherwise specified. In the present disclosure, a combination of two or more preferred aspects or forms is a more preferred aspect or form. In the present disclosure, a "solid component" means a component that is solid at 25°C and 1 atmosphere, and a "liquid component" means a component that is liquid at 25°C and 1 atmosphere.

[0014] <Method for manufacturing quasi-solid battery> A method for manufacturing a quasi-solid battery according to the present disclosure is to manufacture a quasi-solid battery having a volume average particle size of 10 μm to 500 μm and a specific surface area of ​​20 m2, which comprises an electrode active material and a conductive additive. ２ / g~25m ２ / g of aggregates, agitating the aggregates while heating them to 100°C to 300°C under reduced pressure, mixing the aggregates with an electrolyte solution to obtain an electrode material, and applying the electrode material to a support to form an electrode layer. The "quasi-solid battery" in the present disclosure is a secondary battery that includes an electrode layer formed using an electrode material in which an electrolyte solution is mixed with an electrode active material and a conductive additive.

[0015] The present inventors have found that the viscosity of an electrode material containing an electrode active material decreases as the particle size of the electrode active material increases. On the other hand, the present inventors have also noted that the smaller the particle size of the electrode active material, the higher the adhesion of the electrode material to a support and the better the application. These two seemingly contradictory characteristics are usually difficult to achieve together. However, the present inventors have discovered a method for producing an electrode material that combines the effect of lowering the viscosity of the material due to the large-sized aggregates and the effect of improving adhesion due to the small-sized aggregates or particles by forming an electrode material by mixing the aggregates with an electrolyte solution. The electrode material has a specific average particle size of 10 μm to 500 μm and a specific surface area of ​​20 m. ２ / g~25m ２ It is estimated that by stirring the aggregates of 1 / g while heating them to 100°C to 300°C under reduced pressure and then mixing them with an electrolyte solution to form an electrode material, moisture due to humidity in the aggregates is removed, making the aggregates more likely to break down when the electrode material is applied, resulting in a low viscosity effect in the state of the electrode material, and after the electrode layer is formed, at least a portion of the aggregates are broken down into small-sized particles or droplets, improving adhesion to the support, and providing excellent continuous supply of the electrode material and suppressing application defects.

[0016] (Step of forming aggregates) The method for producing a quasi-solid battery according to the present disclosure includes forming an aggregate of an electrode active material and a conductive additive, the aggregate having a volume average particle size of 10 μm to 500 μm and a specific surface area of ​​20 m ２ / g~25m ２ The method includes a step of forming aggregates of 0.1g / g. The aggregates are also referred to as "composite aggregates." In the step of forming the aggregates, an electrode active material and a conductive additive may be mixed to form aggregates. However, from the viewpoints of granulation ability, continuous supply of electrode material, and suppression of coating defects, the step of mixing and stirring the electrode active material and the conductive additive, and then applying a pressure of 20 kN / cm to 2,000 kN / cm to form aggregates is preferred. More preferred is a step of mixing and stirring the electrode active material and the conductive additive, then applying a pressure of 20 kN / cm to 2,000 kN / cm to granulate, and then milling. Furthermore, in the above embodiment, aggregates having the desired volume average particle size and specific surface area can be easily obtained.

[0017] Furthermore, from the viewpoints of continuous supply of the electrode material and suppression of application defects, it is preferable that, in the step of forming the aggregates, the volume average particle size of the aggregates after milling the aggregates is larger than the thickness of the electrode layer to be formed, which will be described later. By crushing the aggregates during the formation of the electrode layer, a viscosity reduction effect is obtained in the state of the electrode material, and adhesion to the support is obtained during application.

[0018] In the present disclosure, the granulation method is not particularly limited, and known methods can be used. For example, known granulators can be used as the granulation means used in the granulation method. Among these, roller compactors are preferably used. Specific examples of devices used in the granulation method include dry granulation devices such as Freund Turbo's dry granulator (such as the Roller Compactor FT) and Powrex's dry granulator (the Chilsonator). The device used in the granulation method may be a device using a mechanochemical method. By using a device using a mechanochemical method, aggregates are obtained and the powder surface is also smoothed. Alternatively, the electrode active material and the conductive additive may be premixed by a mixing means, and then the aggregates may be formed by a granulation means. In the present disclosure, known granulation and mixing means can be used.

[0019] The volume-average particle size of the agglomerates obtained by the agglomerate-forming step is 10 μm to 500 μm. Within this range, the agglomerates sufficiently reduce the viscosity of the electrode material, and the small-sized agglomerates or particles obtained by crushing the agglomerates during application of the electrode material sufficiently improve adhesion, resulting in excellent continuous supply of the electrode material and suppression of application defects. Furthermore, from the viewpoints of continuous supply of the electrode material and suppression of application defects, the volume-average particle size of the agglomerates is preferably 10 μm to 300 μm, more preferably 50 μm to 300 μm, and particularly preferably 100 μm to 250 μm.

[0020] The volume average particle size of the aggregates in the present disclosure is measured using a laser diffraction particle size distribution measuring device (LA960 manufactured by Horiba, Ltd.).

[0021] The specific surface area of ​​the agglomerates obtained by the agglomerate forming step is 20 m ２ / g~25m ２ Within this range, the agglomerates have a sufficient effect of reducing the viscosity of the electrode material, and the small-sized agglomerates or particles obtained by crushing the agglomerates when applying the electrode material have a sufficient effect of improving adhesion, resulting in excellent continuous supply of the electrode material and excellent suppression of application defects. Furthermore, the specific surface area of ​​the agglomerates is preferably 20 m or less from the viewpoint of continuous supply of the electrode material and suppression of application defects. ２ / g~24m ２ / g, and 21m ２ / g~23m ２ It is more preferable that the SiO2 content is 1 / g.

[0022] The specific surface area of ​​the aggregates in this disclosure is measured using a BET specific surface area meter (BELSORP MINI manufactured by Microtrac-Bell Inc.) Nitrogen gas is used as the adsorption gas.

[0023] The amount of electrode active material added in the step of forming the aggregate may be appropriately selected depending on the desired electrode layer, but is preferably 80% by mass to 99.99% by mass, more preferably 90% by mass to 99.9% by mass, and particularly preferably 95% by mass to 99.7% by mass, relative to the total amount of electrode active material and conductive aid. The amount of conductive aid added in the step of forming the aggregate may be appropriately selected depending on the desired electrode layer, but is preferably 0.01% by mass to 20% by mass, more preferably 0.1% by mass to 10% by mass, and particularly preferably 0.3% by mass to 5% by mass, relative to the total amount of electrode active material and conductive aid.

[0024] - Electrode active material - An electrode active material is a material capable of inserting and releasing ions of a metal element belonging to Group 1 or Group 2 of the periodic table. The electrode active material is contained in a solid component. Examples of the electrode active material include a positive electrode active material and a negative electrode active material.

[0025] --Positive Electrode Active Material-- The positive electrode active material is not limited, and any known electrode active material used for positive electrodes can be used. The positive electrode active material is preferably a positive electrode active material that can reversibly insert and release lithium ions.

[0026] Specific examples of the positive electrode active material include transition metal oxides and elements that can be composited with lithium (e.g., sulfur). Among the above, the positive electrode active material is preferably a transition metal oxide.

[0027] The transition metal oxide is preferably a transition metal oxide containing at least one transition metal element (hereinafter referred to as "element Ma") selected from the group consisting of Co (cobalt), Ni (nickel), Fe (iron), Mn (manganese), Cu (copper), and V (vanadium).

[0028] When the transition metal oxide contains Li and the element Ma, the molar ratio of Li to Ma (Li / Ma) is preferably 0.3 to 2.2.

[0029] The transition metal oxide may also contain at least one transition metal element (hereinafter referred to as "element Mb") selected from the group consisting of Group 1 elements other than lithium, Group 2 elements, Al (aluminum), Ga (gallium), In (indium), Ge (germanium), Sn (tin), Pb (lead), Sb (antimony), Bi (bismuth), Si (silicon), P (phosphorus), and B (boron). The content of element Mb is preferably 0 mol % to 30 mol % relative to the amount of element Ma.

[0030] Examples of transition metal oxides include transition metal oxides having a layered rock salt structure, transition metal oxides having a spinel structure, lithium-containing transition metal phosphate compounds, lithium-containing transition metal halide phosphate compounds, and lithium-containing transition metal silicate compounds.

[0031] Examples of transition metal oxides having a layered rock salt structure include LiCoO ２ (Lithium cobalt oxide [LCO]), LiNi ２ O ２ (lithium nickel oxide), LiNi ０．８５ Co ０．１０ Al ０．０５ O ２ (nickel cobalt lithium aluminum oxide [NCA]), LiNi １／３ Co １／３ Mn １／３ O ２ (lithium nickel manganese cobalt oxide [NMC]), and LiNi ０．５ Mn ０．５ O ２ (lithium manganese nickel oxide).

[0032] Examples of transition metal oxides having a spinel structure include LiCoMnO ４ , Li ２ FeMn ３ O ８ , Li ２ CuMn ３ O ８ , Li ２ CrMn ３ O ８ , and Li ２ NiMn ３ O ８ Examples include:

[0033] Examples of lithium-containing transition metal phosphate compounds include olivine-type iron phosphate salts (e.g., LiFePO ４ , and Li ３ Fe ２ (P.O. ４ ) ３ ), iron pyrophosphate (e.g., LiFeP ２ O ７ ), cobalt phosphate salts (e.g., LiCoPO ４), monoclinic Nasicon-type vanadium phosphate salts (e.g., Li ３ V ２ (P.O. ４ ) ３ (Lithium vanadium phosphate)).

[0034] Examples of lithium-containing transition metal halophosphate compounds include iron fluorophosphates (e.g., Li ２ FePO ４ F), manganese fluorophosphate salts (e.g., Li ２ MnPO ４ F), and cobalt fluorophosphate salts (e.g., Li ２ CoPO ４ F).

[0035] Examples of lithium-containing transition metal silicate compounds include Li ２ FeSiO ４ , Li ２ MnSiO ４ , and Li ２ CoSiO ４ Examples include:

[0036] The transition metal oxide is preferably a transition metal oxide having a layered rock salt structure, such as LiCoO ２ (Lithium cobalt oxide [LCO]), LiNi ０．８５ Co ０．１０ Al ０．０５ O ２ (nickel cobalt lithium aluminum oxide [NCA]), and LiNi １／３ Co １／３ Mn １／３ O ２ (lithium nickel manganese cobalt oxide [NMC]) is more preferable.

[0037] The positive electrode active material may be a commercially available product or a synthetic product produced by a known method (e.g., a calcination method). For example, the positive electrode active material obtained by the calcination method may be washed with water, an acidic aqueous solution, an alkaline aqueous solution, or an organic solvent. The positive electrode active material may also have a carbon coating on its surface.

[0038] The shape of the positive electrode active material is not limited, but from the viewpoint of ease of handling, it is preferably in the form of particles.

[0039] The volume average particle size of the positive electrode active material is not limited and can be, for example, 0.1 μm to 50 μm. The volume average particle size of the positive electrode active material is preferably 0.3 μm to 40 μm, and more preferably 0.5 μm to 30 μm. When the volume average particle size of the positive electrode active material is 0.3 μm or more, scattering of the positive electrode active material during handling can be suppressed. When the volume average particle size of the positive electrode active material is 40 μm or less, the thickness of the electrode molded body can be easily adjusted and the occurrence of voids during the molding process can be suppressed.

[0040] The volume average particle size of the positive electrode active material is measured by the following method. A dispersion containing 0.1 mass % or less of the positive electrode active material is prepared by mixing the positive electrode active material with a solvent (e.g., pure water, ethanol, heptane, octane, toluene, or xylene). The dispersion is irradiated with 1 kHz ultrasound for 10 minutes and used as a measurement sample. Using a laser diffraction / scattering particle size distribution measurement device (e.g., LA-960 manufactured by Horiba, Ltd.), data is acquired 50 times at a temperature of 25°C, and the volume average particle size is determined from the volume frequency particle size distribution. A quartz cell is used as the measurement cell. The above measurement is performed using five samples, and the average of the measured values ​​is used as the volume average particle size of the positive electrode active material. For other detailed conditions, refer to "JIS Z 8828:2013" as necessary.

[0041] Examples of methods for adjusting the particle size of the positive electrode active material include methods using a pulverizer, a crusher, or a classifier. Alternatively, known milling methods may be used to adjust the particle size of the positive electrode active material.

[0042] The positive electrode active material may be used alone or in combination of two or more. Even when one type of positive electrode active material is used, positive electrode active materials having different particle sizes may be used in combination.

[0043] --Negative Electrode Active Material-- The negative electrode active material is not limited, and any known electrode active material used for negative electrodes can be used. The negative electrode active material is preferably a negative electrode active material that can reversibly insert and release lithium ions.

[0044] Examples of the negative electrode active material include carbonaceous materials, metal oxides (e.g., tin oxide), silicon oxide, metal composite oxides, lithium alone, lithium alloys (e.g., lithium-aluminum alloys), and metals capable of forming alloys with lithium (e.g., Sn, Si, and In). Among these, the negative electrode active material is preferably a carbonaceous material or a lithium composite oxide from the viewpoint of reliability.

[0045] Carbonaceous materials are materials consisting essentially of carbon. Examples of carbonaceous materials include petroleum pitch, carbon black (e.g., acetylene black), graphite (e.g., natural graphite and artificial graphite (e.g., vapor-grown graphite)), hard carbon, and carbonaceous materials obtained by calcining synthetic resins (e.g., polyacrylonitrile (PAN) and furfuryl alcohol resin). Examples of carbonaceous materials include carbon fibers (e.g., polyacrylonitrile-based carbon fibers, cellulose-based carbon fibers, pitch-based carbon fibers, vapor-grown carbon fibers, dehydrated PVA (polyvinyl alcohol)-based carbon fibers, lignin carbon fibers, glassy carbon fibers, and activated carbon fibers). Examples of graphite include mesophase microspheres, graphite whiskers, and tabular graphite. In this disclosure, "tabular" refers to a shape having two major planes facing in opposite directions.

[0046] The metal composite oxide is preferably a metal composite oxide capable of absorbing and desorbing lithium. From the viewpoint of high current density charge / discharge characteristics, the metal composite oxide capable of absorbing and desorbing lithium preferably contains at least one element selected from the group consisting of titanium and lithium.

[0047] The metal oxide and metal composite oxide are particularly preferably amorphous oxides.

[0048] The metal oxides and metal composite oxides are also preferably chalcogenides, which are reaction products of metal elements and elements of Group 16 of the periodic table.

[0049] Among the group of compounds consisting of amorphous oxides and chalcogenides, amorphous oxides and chalcogenides of metalloid elements are preferred, and oxides and chalcogenides containing at least one element selected from the group consisting of elements of Groups 13 to 15 in the periodic table, Al, Ga, Si, Sn, Ge, Pb, Sb, and Bi are more preferred.

[0050] It is also preferable that the negative electrode active material further contains titanium. From the viewpoint that the volume change during the absorption and desorption of lithium ions is small, and thus rapid charge and discharge characteristics are excellent, and that deterioration of the electrode is suppressed, thereby enabling an improvement in the life of the lithium ion secondary battery, the negative electrode active material containing titanium is preferably Li ４ Ti ５ O １２ (lithium titanate [LTO]) is preferred.

[0051] The negative electrode active material may be a commercially available product or a synthetic product produced by a known method (e.g., a calcination method). For example, the negative electrode active material obtained by the calcination method may be washed with water, an acidic aqueous solution, an alkaline aqueous solution, or an organic solvent.

[0052] The negative electrode active material is available, for example, as CGB20 (Nippon Graphite Industries Co., Ltd.).

[0053] The composition of the negative electrode active material is measured using inductively coupled plasma (ICP) emission spectroscopy.

[0054] The shape of the negative electrode active material is not limited, but is preferably particulate from the viewpoints of ease of handling and ease of control of uniformity during mass production.

[0055] The volume average particle size of the negative electrode active material is preferably 0.1 μm to 60 μm, more preferably 0.3 μm to 50 μm, and particularly preferably 0.5 μm to 40 μm. The volume average particle size of the negative electrode active material is measured by a method similar to the method for measuring the volume average particle size of the positive electrode active material.

[0056] The particle size of the negative electrode active material can be adjusted, for example, by using a pulverizer or a classifier.

[0057] The negative electrode active material may be used alone or in combination of two or more. Even when one type of negative electrode active material is used, negative electrode active materials having different particle sizes may be used in combination.

[0058] The surfaces of the positive electrode active material and the negative electrode active material may each be coated with a surface coating agent. Examples of the surface coating agent include metal oxides containing Ti, Nb, Ta, W, Zr, Si, or Li. Examples of the metal oxide include titanate spinel, tantalum-based oxides, niobium-based oxides, and lithium niobate-based compounds.

[0059] Conductive Aid—The conductive aid is not limited, and any known conductive aid can be used. The conductive aid is contained in the solid component.

[0060] Examples of conductive additives include graphite (e.g., natural graphite and artificial graphite), carbon black (e.g., acetylene black, ketjen black, and furnace black), amorphous carbon (e.g., needle coke), carbon fibers (e.g., vapor-grown carbon fibers and carbon nanotubes), other carbonaceous materials (e.g., graphene and fullerene), metal powders (e.g., copper powder and nickel powder), metal fibers (e.g., copper fibers and nickel fibers), and conductive polymers (e.g., polyaniline, polypyrrole, polythiophene, polyacetylene, and polyphenylene derivatives).

[0061] The conductive additive may be used alone or in combination of two or more kinds.

[0062] (Stirring Step) The method for producing a quasi-solid battery according to the present disclosure includes a step of stirring the aggregates while heating them under reduced pressure to 100° C. to 300° C. It is presumed that the stirring step removes moisture from the aggregates formed in the aggregate-forming step, making the aggregates more likely to be broken down when applied.

[0063] The pressure in the stirring step may be any pressure lower than atmospheric pressure, but from the viewpoint of suppressing poor application, the pressure is preferably 0.001 kPa to 50 kPa, more preferably 0.01 kPa to 20 kPa, even more preferably 0.1 kPa to 10 kPa, and particularly preferably 0.5 kPa to 5 kPa.

[0064] The stirring temperature in the stirring step is 100°C to 300°C. Within this range, moisture in the aggregates is sufficiently removed, and the effect of improving adhesion due to the small-sized aggregates or particles obtained by crushing the aggregates when applying the electrode material is sufficiently obtained, resulting in excellent suppression of coating defects. Furthermore, from the viewpoint of suppressing coating defects, the stirring temperature is preferably 150°C to 300°C, more preferably 200°C to 300°C, and particularly preferably 250°C to 300°C.

[0065] The moisture content of the aggregates after the stirring step is preferably 300 ppm or less, more preferably 200 ppm or less, and even more preferably 150 ppm or less, from the viewpoint of suppressing poor application.

[0066] The moisture content of the aggregates in the present disclosure is measured using a Karl Fischer moisture meter (CA-200 manufactured by Mitsubishi Chemical Analytech Co., Ltd.).

[0067] From the viewpoints of continuous supply of the electrode material and suppression of coating defects, it is preferable that the volume average particle size of the aggregates in the electrode layer described below is smaller than the volume average particle size of the aggregates in the stirring step. Note that the volume average particle size of the aggregates in the stirring step is the volume average particle size of the aggregates after stirring has been completed.

[0068] The vacuum heating and stirring means used in the stirring step is not particularly limited, and known means can be used. Also, known vacuum means, heating means, and stirring means may be used in combination. Among these, it is preferable to use a stirring type vacuum heating dryer. Specific examples include Ribocone manufactured by Okawara Manufacturing Co., Ltd.

[0069] (Step of Obtaining Electrode Material) The method for producing a quasi-solid battery according to the present disclosure includes a step of mixing the aggregate with an electrolyte solution to obtain an electrode material. Details of the electrolyte solution used in the present disclosure will be described later. The amount of electrolyte solution added in the step of obtaining the electrode material may be appropriately selected depending on the desired electrode layer, but is preferably 50 mass % or less, and more preferably 40 mass % or less, relative to the total mass of the electrode material. The lower limit of the amount of electrolyte solution added relative to the total volume of the electrode material film is not particularly limited, and is preferably 5 mass % or more, and more preferably 10 mass % or more.

[0070] The mixing means used in the step of obtaining the electrode material is not particularly limited, and any known mixing means can be used, such as a ball mill, a bead mill, a planetary mixer, a blade mixer, a roll mill, a kneader, or a disk mill.

[0071] In the obtained electrode material, from the viewpoints of recyclability, improvement of energy density, and prevention of coating defects, the content of the binder is preferably 0% by mass to 5% by mass, more preferably 0% by mass to 1% by mass, and even more preferably 0% by mass to 0.1% by mass, based on the total solid content of the electrode material. Furthermore, from the viewpoints of recyclability, improvement of energy density, and prevention of coating defects, it is particularly preferable that the obtained electrode material does not contain a binder.

[0072] -Electrolyte- The electrolyte is not particularly limited, and a known electrolyte can be used. For example, the electrolyte contains an electrolyte and a solvent. Specific examples of the electrolyte include a lithium salt compound as the electrolyte and a carbonate compound as the solvent.

[0073] An example of the lithium salt compound is lithium hexafluorophosphate. The electrolyte solution may contain one kind of lithium salt compound alone, or may contain two or more kinds of lithium salt compounds.

[0074] Examples of carbonate compounds include linear carbonate compounds such as ethyl methyl carbonate (also referred to as EMC), dimethyl carbonate (also referred to as DMC), and diethyl carbonate (DEC), and cyclic carbonate compounds such as ethylene carbonate (also referred to as EC) and propylene carbonate (also referred to as PC). The electrolyte may contain one type of carbonate compound alone, or may contain two or more types of carbonate compounds, or may use one or more linear carbonate compounds and one or more cyclic carbonate compounds in combination.

[0075] As the electrolyte contained in the electrolytic solution, for example, a known inorganic solid electrolyte can be used.

[0076] An ionic liquid may be used as a component of the electrolytic solution, for example. The ionic liquid may be used as either an electrolyte or a solvent.

[0077] The electrode material may contain, as a liquid component, a solvent (hereinafter simply referred to as "solvent") other than the solvent contained as a component of the electrolyte. Examples of the solvent include alcohol compound solvents, ether compound solvents, amide compound solvents, amino compound solvents, ketone compound solvents, aromatic compound solvents, aliphatic compound solvents, and nitrile compound solvents.

[0078] The boiling point of the solvent at normal pressure (i.e., 1 atmosphere) is preferably 50° C. or higher, and more preferably 70° C. or higher. The upper limit of the boiling point of the solvent at normal pressure (i.e., 1 atmosphere) is preferably 250° C. or lower, and more preferably 220° C. or lower.

[0079] The solvents may be used alone or in combination of two or more.

[0080] The content of the liquid components (i.e., the electrolyte and solvent) relative to the total volume of the electrode material is preferably 48% by volume or less, and may be 45% by volume or less, or 40% by volume or less. The lower limit of the content of the liquid components relative to the total volume of the electrode material film is not limited, and may be 28% by volume or more, or 30% by volume or more.

[0081] Note that the liquid components contained in the electrode material, i.e., the components in the electrode material that are liquid at 25° C., are preferably liquid even at −10° C., and are preferably liquid even at −20° C. In other words, the components in the electrode material that are liquid at 25° C. are preferably components that do not solidify at −10° C., and are preferably components that do not solidify even at −20° C.

[0082] -Other Components- In addition to the above-mentioned components, the electrode material may contain binders, dispersants, other additives, etc. Examples of binders include fluorine-containing resins, hydrocarbon-based thermoplastic resins, acrylic resins, and urethane resins. Furthermore, the dispersant may be any known dispersant capable of dispersing the substance to be dispersed. Furthermore, known additives added to electrodes can be used as other additives. The solid component concentration is preferably 30% to 70% by mass, more preferably 40% to 70% by mass, and even more preferably 50% to 70% by mass. The solid component refers to components excluding the electrolyte and the solvent.

[0083] (Step of forming an electrode layer) The manufacturing method of a quasi-solid battery according to the present disclosure includes a step of applying the electrode material onto a support to form an electrode layer. The means for applying the electrode material onto the support in the step of forming the electrode layer may be any means capable of applying a required amount of electrode material onto the support. Examples of the means for applying the electrode material to the support include means for intermittently or continuously supplying the electrode material onto the support (e.g., a hopper, a screw feeder, a disk feeder, a vibrating feeder, etc.), and various applying means (e.g., applying means using a slit applying method, a bar applying method, a blade applying method, etc.). Furthermore, when applying the electrode material onto the support, a regulating frame or a mesh frame may be used to ensure uniform application of the mixture.

[0084] The thickness of the electrode layer may be appropriately selected as desired, but is preferably 10 μm to 1,000 μm, more preferably 20 μm to 500 μm, and particularly preferably 70 μm to 230 μm.

[0085] The thickness of the electrode layer is the arithmetic mean value of the thicknesses measured at three locations by cross-sectional observation, which can be performed using a known microscope (for example, a scanning electron microscope).

[0086] -Support- The support is not particularly limited as long as it is a support on whose surface an electrode layer can be formed. In particular, from the viewpoint of continuously forming an electrode layer, it is preferable to use a long support. In the case of a long support, the width of the support may be determined depending on the size of the electrode layer, the width in the width direction of the pressing member (for example, a blade, a roller, etc.) described above, and the like.

[0087] A specific example of a preferred support is a current collector. The current collector, which is an example of a support, is not particularly limited, and known current collectors (positive electrode current collectors and negative electrode current collectors) can be used.

[0088] Examples of the positive electrode current collector include aluminum, aluminum alloy, stainless steel, nickel, and titanium. The positive electrode current collector is preferably aluminum or an aluminum alloy. The positive electrode current collector may be aluminum having a coating layer on its surface that contains one or more of carbon, nickel, titanium, silver, gold, platinum, and vanadium oxide.

[0089] Examples of the negative electrode current collector include aluminum, copper, a copper alloy, stainless steel, nickel, and titanium. The negative electrode current collector is preferably aluminum, copper, a copper alloy, or stainless steel, and more preferably copper or a copper alloy. The negative electrode current collector may be copper or stainless steel having a coating layer on its surface containing one or more of carbon, nickel, titanium, silver, and lithium.

[0090] The current collector is preferably an aluminum foil (including an aluminum foil having the above-described coating layer on its surface) or a copper foil (including a copper foil having the above-described coating layer on its surface). Aluminum foil is usually used as a current collector in a positive electrode. Copper foil is usually used as a current collector in a negative electrode.

[0091] The support may be a laminate of a metal layer exemplified as the positive electrode current collector or the negative electrode current collector described above and a resin film. Examples of the resin film used in the laminate include polyethylene terephthalate (PET) film, polypropylene (PP) film, polyethylene (PE) film, cyclic olefin polymer (COP, COC) film, triacetyl cellulose (TAC) polyimide (PI) film, and polyamide (PA) film.

[0092] An example of the support is a release material. Examples of the release material, which is an example of the support, include release paper (e.g., release paper manufactured by Lintec Corporation), a film having a release layer, and paper having a release layer, and among these, release paper is preferred. When a release material is used as the support, the electrode material film formed on the release material can be transferred to the current collector by utilizing the releasability of the release material.

[0093] The thickness of the support (preferably the current collector) is preferably 3 μm or more, more preferably 5 μm or more, and particularly preferably 10 μm or more, from the viewpoint of transportability, etc. The thickness is preferably 100 μm or less, more preferably 70 μm or less, and particularly preferably 50 μm or less, from the viewpoint of flexibility and lightness. The thickness of the support is measured in the same manner as the thickness of the electrode material film having a single layer structure.

[0094] The size of the support is not limited, and may be determined depending on the size of the electrode molded body to be produced, the sizes of various members used in the production process, and the like.

[0095] Furthermore, known conveying means can be used as the means for conveying the support, and specific examples of the means for conveying the support include a belt conveyor, a linear motion guide, and a cross roller table.

[0096] In the step of forming the electrode layer, from the viewpoint of suppressing poor application, it is preferable to include a step of applying pressure or vibration to the electrode layer arranged on the support, it is more preferable to include a step of applying vibration to the electrode layer arranged on the support, and it is particularly preferable to include a step of applying pressure and vibration to the electrode layer arranged on the support.

[0097] A method for applying pressure to the electrode layer on the support can be a method of applying pressure from above the electrode layer toward the support. Specific examples of a method for applying pressure to the electrode layer include a method of pressing the electrode layer from above toward the support using a pressing member. In this case, from the viewpoint of suppressing volatilization of the liquid component, it is preferable to place a film on the electrode layer and press the electrode layer from above the film using a pressing member. Examples of pressing members include plate-like members such as blades and scrapers, rollers, flat plate presses, and roll presses.

[0098] -Pressing Member- Preferred examples of the pressing member include a blade and a roller. As described above, the blade and roller as the pressing member may vibrate when they come into contact with the electrode layer. By using a vibrating pressing member, the electrode layer can be vibrated.

[0099] The blade is a plate-like member, and the shape, size, material, etc. of the contact portion that contacts the electrode layer may be appropriately determined depending on the physical properties of the mixture (type of electrode active material, concentration of solid components, composition of the electrolyte (viscosity, surface tension), etc.), the size and thickness of the electrode material film to be formed, etc. Furthermore, it is preferable that the electrode material does not easily adhere to the contact portion of the blade with the mixture. For example, it is preferable that at least the surface of the blade exhibits mold-releasability. For example, the blade may be made of a fluororesin such as polytetrafluoroethylene (PTFE) or a resin such as polyether ether ketone (PEEK), or may be made of a metal such as stainless steel, aluminum, iron, or cemented carbide, or may be made of ceramic. Furthermore, to impart mold-releasability to the surface, the blade may have a surface layer that exhibits mold-releasability (e.g., a surface layer containing a fluororesin, a surface layer containing silicon-based particles and a resin). Furthermore, from the viewpoint of improving wear resistance, the blade may have a high-hardness coating such as titanium oxide, titanium nitride (TiN), or tungsten carbide on the metal or ceramic blade body.

[0100] The roller is a member whose outer circumferential surface is rotatable, and its size, material, etc. may be determined appropriately depending on the physical properties of the electrode material (type of electrode active material, concentration of solid components, composition of the electrolyte (viscosity, surface tension), etc.), the size and thickness of the electrode material film to be formed, etc. The material constituting the outer circumferential surface of the roller may be similar to that of the blade, and may have a surface layer that exhibits release properties. The outer diameter of the roller is not particularly limited, but may be, for example, 20 mm to 30 mm. Furthermore, since the roller rotates, the coefficient of friction between its outer circumferential surface and the mixture can be considered to be 0. However, as this may result in increased adhesion to the mixture, it is preferable to interpose a film between the mixture and the outer circumferential surface of the roller.

[0101] In the step of forming the electrode layer, from the viewpoint of suppressing application defects, it is preferable to apply the electrode material onto the support while applying vibration, and it is more preferable to apply the electrode material onto the support while applying vibration with an amplitude of 1 μm to 100 μm and a frequency of 5 kHz to 500 kHz.

[0102] A method for vibrating the electrode layer on the support may be to use a means for vibrating the electrode layer. Specifically, the method for vibrating the electrode layer may involve contacting a vibrating member from above the electrode layer to vibrate the electrode layer, or vibrating the support on which the electrode layer is disposed to vibrate the electrode layer. The vibrating member may be the same as the pressing member described above. By vibrating the pressing member, vibrations can be imparted to the electrode layer in contact with the vibrating pressing member. In particular, from the viewpoint of forming an electrode material film having a uniform thickness and a uniform concentration distribution of each component, it is preferable to apply pressure and vibration to the electrode layer on the support. Specifically, it is preferable to press the electrode layer on the support from above toward the support using a vibrating pressing member.

[0103] The vibration direction of the pressing member is not particularly limited. The vibration of the pressing member may be continuous or intermittent. The amplitude of the vibration of the pressing member is preferably, for example, 0.1 μm to 200 μm, more preferably 1 μm to 100 μm, and even more preferably 1 μm to 10 μm. The frequency of the vibration of the pressing member is preferably, for example, 50 Hz to 1 MHz, and more preferably 5 kHz to 500 kHz. The frequency of the vibration of the pressing member may include multiple frequencies. For example, the vibration of the pressing member may be such that multiple frequency peaks are detected, such as 150 kHz, 300 kHz, and 450 kHz. The vibration amplitude and frequency can be measured using an acceleration sensor or a vibration measuring device. When multiple frequency peaks are detected during measurement of the vibration of the pressing member, the smallest frequency is defined as the "frequency of the vibration of the pressing member," and the amplitude at this frequency is defined as the "amplitude of the vibration of the molding material." For example, if multiple frequency peaks such as 150 kHz, 300 kHz, and 450 kHz are detected for the vibration of the pressing member, 150 kHz is defined as the "frequency of the vibration of the pressing member," and the amplitude at the frequency of 150 kHz is defined as the "amplitude of the vibration of the pressing member."

[0104] (Other Steps) The method for manufacturing a quasi-solid battery according to the present disclosure may include other steps. Examples of the other steps include a step of pressing the electrode layer, and when the support is release paper, a step of transferring the electrode layer formed on the release paper to a current collector. Another example of the other step is a step of manufacturing a quasi-solid battery using the electrode layer. There are no particular limitations on the method for manufacturing a quasi-solid battery other than using the electrode layer, and known materials and methods can be used.

[0105] The method for manufacturing a quasi-solid-state battery according to the present disclosure may include a step of applying pressure to the electrode layer. By including the step of applying pressure to the electrode layer, it is possible to increase the density of the electrode material and to achieve in-plane uniformity in the density and thickness of the solid component.

[0106] When the electrode layer is pressurized, the pressure is preferably 0.01 MPa to 100 MPa, more preferably 0.1 MPa to 50 MPa, and particularly preferably 0.2 MPa to 10 MPa.

[0107] In the step of pressurizing the electrode layer, the electrode layer may be pressurized in stages using a plurality of pressurizing means. By pressurizing the electrode layer in stages using a plurality of pressurizing means, the density and thickness of the electrode material can be made more uniform.

[0108] In the step of pressurizing the electrode layer, the pressurizing means and the electrode layer (specifically, the support on which the electrode layer is formed) are preferably moved relative to each other. In the present disclosure, "moving the pressurizing means and the electrode layer relative to each other" includes moving the pressurizing means in one direction relative to the electrode layer, moving the electrode layer in one direction relative to the pressurizing means, and moving both the pressurizing means and the electrode layer in one direction, but it is preferable to move the electrode layer in one direction relative to the pressurizing means.

[0109] The means for moving the electrode layer (specifically, the support on which the electrode layer is formed) is not limited, and known conveying means can be used, for example, a belt conveyor, a linear motion guide, and a cross roller table.

[0110] In the step of pressing the electrode layer, from the viewpoint of improving formability, the electrode layer may be heated at, for example, 30° C. to 100° C. before being pressed.

[0111] The present disclosure will be described in detail below with reference to examples, but the present disclosure is not limited thereto. Note that each step in each example described below was carried out in a dry room (low dew point room) at 22°C.

[0112] [Measurement of Volume Average Particle Size of Aggregates] The volume average particle size of the aggregates was measured using a laser diffraction particle size distribution measuring device (LA960 manufactured by Horiba, Ltd.).

[0113] [Measurement of Specific Surface Area of ​​Aggregates] The specific surface area of ​​the aggregates was measured using a BET specific surface area meter (BELSORP MINI manufactured by Microtrac-Bell Co., Ltd.) Nitrogen gas was used as the adsorption gas.

[0114] [Measurement of Moisture Content of Aggregates] The moisture content of the aggregates was measured using a Karl Fischer moisture meter (CA-200, manufactured by Mitsubishi Chemical Analytech Co., Ltd.).

[0115] [Preparation of Aggregate (G1-1)] Aggregate (G1-1) was obtained as follows. A conductive additive (Ketjen black, volume average particle size 40 nm) and a positive electrode active material (lithium iron phosphate, volume average particle size 1.4 μm) were mixed and dispersed in a mass ratio of 0.4 mass% of conductive additive and 99.4 mass% of positive electrode active material to prepare a powder. This was dry granulated using a roller compactor FT manufactured by Freund Turbo Corporation at a roll pressure of 20 kN / cm, and aggregates (granules) of the desired size were removed using a sieve. Thereafter, the aggregates (granules) were treated at 280 ° C. and 1.5 kPa while stirring in an agitation type vacuum heating dryer (Ribocone manufactured by Okawara Seisakusho Co., Ltd.). The volume average particle size of the obtained aggregate (G1-1) was 200 μm, and the specific surface area was 23 m ２ / g, and the water content was 100 ppm.

[0116] [Preparation of Aggregates (G1-2) and (G1-3)] In the preparation of Aggregate (G1-1), the conditions for extracting aggregates (granules) of the desired size using a sieve were changed to obtain Aggregate (G1-2) with a volume average particle size of 50 μm and Aggregate (G1-3) with a volume average particle size of 500 μm. ２ / g, and the water content was 100 ppm.

[0117] [Preparation of Aggregate (G2-1)] In the preparation of Aggregate (G1-1), the roll pressure of the roller compactor FT was changed to 2000 kN / cm to obtain Aggregate (G2-1). The volume average particle size was 200 μm and the specific surface area was 23 m. ２ / g, and the water content was 100 ppm.

[0118] [Preparation of Aggregate (G2-2)] In the preparation of Aggregate (G1-1), the roll pressure of the roller compactor FT was changed to 500 kN / cm to obtain Aggregate (G2-2). The volume average particle size was 200 μm and the specific surface area was 23 m. ２ / g, and the water content was 100 ppm.

[0119] [Preparation of Aggregate (G3)] In the preparation of Aggregate (G1-1), the temperature of the stirring, heating, and vacuum treatment was changed to 150°C to obtain Aggregate (G3) having a volume average particle size of 200 μm. ２ / g, and the water content was 200 ppm.

[0120] [Preparation of Aggregates (G4-1) to (G4-3)] In the preparation of aggregate (G1-1), the mixing ratio of the conductive additive and the positive electrode active material was changed to prepare aggregates having a specific surface area of ​​21 m ２ / g aggregate (G4-1) and a specific surface area of ​​15 m ２ / g aggregate (G4-2) and a specific surface area of ​​50 m ２ / g of aggregates (G4-3) were obtained. The volume average particle size was 200 μm and the moisture content was 100 ppm.

[0121] [Preparation of Aggregate (G5)] In the preparation of Aggregate (G1-1), the positive electrode active material was changed to lithium nickel manganese cobalt oxide to obtain Aggregate (G5) having a volume average particle size of 200 μm. ２ / g, and the water content was 200 ppm.

[0122] [Preparation of Aggregate (G6)] Aggregate (G6) was obtained without the treatment in the agitation type vacuum heating dryer in the preparation of Aggregate (G1-1). The volume average particle size was 210 μm and the specific surface area was 23 m ２ / g, and the water content was 1,500 ppm.

[0123] [Preparation of Aggregates (G7-1) and (G7-2)] In the preparation of Aggregate (G1-1), the conditions for extracting aggregates (granules) of the desired size using a sieve were changed to obtain Aggregate (G7-1) with a volume average particle size of 5 μm and Aggregate (G7-2) with a volume average particle size of 1,000 μm. The specific surface area was 23 m ２ / g, and the water content was 100 ppm.

[0124] [Preparation of Electrolyte (X)] LiPF 5 was added to a mixed solvent of ethylene carbonate (EC), propylene carbonate (PC), and diethyl carbonate (DEC). ６ (Electrolyte) was mixed, and vinylene carbonate (VC) was further mixed therewith to obtain an electrolytic solution (X).

[0125] [Preparation of Support (S)] A positive electrode current collector (aluminum foil, average thickness 20 μm, Ra=0.5 μm) was used as the support (S). Note that Ra of the current collector refers to the arithmetic mean roughness Ra of the surface on which the electrode material film is formed.

[0126] [Preparation of Pressing Member (B)] A stainless steel blade was used as the pressing member (B) for film formation.

[0127] Example 1 120 g of aggregate (G1-1) and 32 g of electrolyte (X) were stirred and mixed in a mixer (Thinky Mixer ARE-310) to obtain a mixture (M). The mixture (M1) was applied to a conveyed support (S) using a twin-shaft screw feeder manufactured by Seiwa Giken Co., Ltd., to form a film with a thickness of approximately 300 μm. Subsequently, the film formed on the support (S) was pressed using a pressing member (B). Specifically, the pressing member was positioned so that the distance between the support and the tip of the pressing member was 200 μm. Thereafter, the support (S) was conveyed and moved, and the film formed on the support (S) was passed through the gap while being brought into contact with the pressing member (B). This formed an electrode material film with a thickness of 200 μm on the support. The solid component concentration of the obtained electrode material film was 56% by volume.

[0128] Examples 2 to 8 An electrode material film having a thickness of 200 μm and a solid component concentration of 56% by volume was obtained on a support in the same manner as in Example 1, except that aggregate (G1-1) was replaced with aggregate (G1-2), aggregate (G1-3), aggregate (G2-1), aggregate (G2-2), aggregate (G3), aggregate (G4-1), or aggregate (G5).

[0129] Comparative Examples 1 to 5 An electrode material film having a thickness of 200 μm and a solid component concentration of 56% by volume was obtained on a support in the same manner as in Example 1, except that aggregate (G1-1) was replaced with aggregate (G6), aggregate (G4-2), aggregate (G4-3), aggregate (G7-1), or aggregate (G7-2).

[0130] [Evaluation of Continuous Supply Ability] Evaluation of continuous supply ability was carried out using a syringe-type air pressure dispenser. The mixture obtained in each of the above examples was filled into a syringe, and the mixture was discharged from the syringe using a dispenser MS-1D manufactured by Musashi Engineering Co., Ltd. The pressure at which the material could be continuously discharged was recorded, and the continuous supply ability was evaluated according to the following criteria. -Evaluation Criteria- A: The discharge pressure of the mixture is 300 kPa or less. B: The discharge pressure of the mixture is greater than 300 kPa and less than 400 kPa. C: The discharge pressure of the mixture is greater than 400 kPa and less than 500 kPa. D: The discharge pressure of the mixture is greater than 500 kPa and less than 600 kPa. E: The discharge pressure of the mixture is greater than 600 kPa.

[0131] [Evaluation of Suppression of Coating Defects] The evaluation of suppression of coating defects was performed using an image inspection device manufactured by the present inventors. The image inspection device includes an XY stage on which the support on which the electrode material film is formed is placed, a CCD (Charge Coupled Device) camera connected to a Z-axis guide installed above the XY stage, and a line light. When the electrode material film is imaged with the CCD camera, areas where the film is not applied or missing are detected by a change in color. Using the XY stage and the Z-axis guide, the electrode material film, the CCD camera, and the line light were moved to capture 140 images of the entire surface of the 210 mm x 150 mm electrode material film obtained in each example, with a 16 mm x 16 mm field of view. The number of images containing areas where the film is not applied was counted, and the ratio of the number of images of the areas where the film is not applied to the total number of images of the entire surface was calculated. The coating property was evaluated according to the following criteria. -Evaluation criteria- A: The percentage of captured images containing areas where the film is not applied is 1% or less. B: The percentage of captured images containing areas where the film is not applied is more than 1% and not more than 3%. C: The percentage of captured images containing areas where the film is not applied is more than 3% and not more than 5%. D: The percentage of captured images containing areas where the film is not applied is more than 5% and not more than 10%. E: The percentage of captured images containing areas where the film is not applied is more than 10%.

[0132] The evaluation results are shown in Table 1.

[0133]

[0134] As shown in Table 1, the manufacturing methods of Examples 1 to 8, which are manufacturing methods of quasi-solid-state batteries according to the present disclosure, are superior to the manufacturing methods of Comparative Examples 1 to 5 in terms of continuous supply of electrode material and suppression of coating defects.

[0135] The disclosure of Japanese Patent Application No. 2024-050267, filed on March 26, 2024, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards mentioned herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A composite electrode consisting of an electrode active material and a conductive additive, with a volume average particle size of 10 μm to 500 μm and a specific surface area of ​​20 m ２ / g~25m ２ / g of aggregates; stirring the aggregates while heating them to 100°C to 300°C under reduced pressure; mixing the aggregates with an electrolyte solution to obtain an electrode material; and applying the electrode material onto a support to form an electrode layer.

2. The method for producing a quasi-solid-state battery according to claim 1, wherein the step of forming the aggregates comprises mixing and stirring the electrode active material and the conductive additive, granulating them under a pressure of 20 kN / cm to 2,000 kN / cm, and then milling the mixture.

3. The method for manufacturing a quasi-solid battery according to claim 2, wherein in the step of forming the aggregates, the volume average particle size of the aggregates after milling the aggregates is larger than the thickness of the electrode layer to be formed.

4. The method for producing a quasi-solid battery according to claim 1 or 2, wherein the moisture content of the aggregates after the stirring step is 200 ppm or less.

5. The method for producing a quasi-solid battery according to claim 1 or 2, wherein in the step of forming the electrode layer, the electrode material is applied onto the support while applying vibrations with an amplitude of 1 μm to 100 μm and a frequency of 5 kHz to 500 kHz.

6. The method for producing a quasi-solid battery according to claim 1 or 2, wherein the electrode material does not contain a binder.

7. The method for producing a quasi-solid battery according to claim 1 or 2, wherein the stirring step is carried out under a reduced pressure of 0.1 kPa to 10 kPa.

8. The method for producing a quasi-solid battery according to claim 1 or 2, wherein the volume average particle size of the aggregates in the electrode layer is smaller than the volume average particle size of the aggregates in the stirring step.

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