JP7407286B2 - Inorganic solid electrolyte-containing composition, all-solid-state secondary battery sheet and all-solid-state secondary battery, and manufacturing method of all-solid-state secondary battery sheet and all-solid-state secondary battery - Google Patents

Description

The present invention relates to an inorganic solid electrolyte-containing composition, an all-solid-state secondary battery sheet, an all-solid-state secondary battery, and a method for producing an all-solid-state secondary battery sheet and an all-solid-state secondary battery.

All-solid-state secondary batteries have a negative electrode, an electrolyte, and a positive electrode all made of solid materials, and can greatly improve the safety and reliability, which are issues faced by batteries using organic electrolytes. It is also said that it will be possible to extend the lifespan. Furthermore, the all-solid-state secondary battery can have a structure in which electrodes and electrolytes are directly arranged in series. Therefore, it is possible to achieve higher energy density than secondary batteries using organic electrolytes, and is expected to be applied to electric vehicles, large storage batteries, etc.

In such an all-solid-state secondary battery, materials forming constituent layers (solid electrolyte layer, negative electrode active material layer, positive electrode active material layer, etc.) include inorganic solid electrolytes, active materials, and the like. Inorganic solid electrolytes, particularly oxide-based inorganic solid electrolytes and sulfide-based inorganic solid electrolytes, have recently attracted attention as electrolyte materials having high ionic conductivity approaching that of organic electrolytes.
Materials containing the above-mentioned inorganic solid electrolyte and the like have been proposed as materials for forming constituent layers of all-solid-state secondary batteries (constituent layer forming materials). For example, Patent Document 1 describes an inorganic solid electrolyte (A) having conductivity for metal ions belonging to Group 1 or Group 2 of the periodic table, and a macromonomer having a number average molecular weight of 1,000 or more as a side chain component. A solid electrolyte composition is described that includes binder particles (B) made of a polymer incorporating (X) and having an average particle diameter of 10 nm or more and 1,000 nm or less, and a dispersion medium (C).

Japanese Patent Application Publication No. 2015-088486

Since the constituent layers of all-solid-state secondary batteries are formed of solid particles (inorganic solid electrolytes, active materials, conductive additives, etc.), the interfacial contact between solid particles is restricted, resulting in an increase in interfacial resistance (ionic conductivity (decreases).
As the interfacial resistance between solid particles increases, the battery resistance of the all-solid-state secondary battery also increases. Furthermore, the increase in battery resistance is further accelerated by voids between solid particles that occur during charging and discharging of the all-solid-state secondary battery, which ultimately leads to a decrease in the cycle characteristics of the all-solid-state secondary battery.
The increase in battery resistance is caused not only by the interfacial contact between solid particles, but also by the uneven presence (arrangement) of solid particles in the constituent layers, and also by the surface smoothness (also called surface flatness) of the constituent layers. ) is also a factor. Therefore, when forming a constituent layer using a constituent layer-forming material, the constituent layer-forming material has not only the dispersibility of solid particles immediately after preparation, but also the property to stably maintain the dispersibility of solid particles immediately after preparation (dispersion). Stability) and properties (surface smoothness) that facilitate the formation of a coating film with a flat surface (good surface properties) are also required.

However, in Patent Document 1, no study is conducted based on such a viewpoint. Moreover, in recent years, research and development for improving the performance and practical application of electric vehicles has progressed rapidly, and demands for battery performance (for example, cycle characteristics) of all-solid-state secondary batteries have become even higher.

The present invention is an inorganic solid electrolyte-containing composition with excellent dispersion stability and surface smoothness, which can be used as a constituent layer forming material of an all-solid-state secondary battery to further suppress increases in battery resistance and provide excellent cycle performance. An object of the present invention is to provide an inorganic solid electrolyte-containing composition that can realize the following characteristics. The present invention also provides an all-solid-state secondary battery sheet and an all-solid-state secondary battery, and a method for manufacturing an all-solid-state secondary battery sheet and an all-solid-state secondary battery using this inorganic solid electrolyte-containing composition. The challenge is to provide.

The present inventors have conducted various studies focusing on polymer binders used in combination with solid particles such as inorganic solid electrolytes and dispersion media. By introducing a hydrogen bonding group (BHa) that can form two or more hydrogen bonds into the side chain, and controlling the solubility of the polymer in the dispersion medium using this hydrogen bonding group (BHa), We have found that the above problems can be solved.
That is, in an inorganic solid electrolyte-containing composition containing an inorganic solid electrolyte and a dispersion medium, the hydrogen-bonding group (BHa) introduced into the side chain of the polymer is used to dissolve the binder component containing this polymer in the dispersion medium. It has been found that by developing the properties, it is possible to form a coating film with a flat surface while suppressing reagglomeration or sedimentation of solid particles such as inorganic solid electrolytes over time. On the other hand, when forming a film using an inorganic solid electrolyte-containing composition, the hydrogen-bonding group (BHa) is used to reduce the solubility of the binder constituent components in the dispersion medium and solidify or precipitate them as a polymer binder. It was discovered that inorganic solid electrolytes can be bonded together while suppressing an increase in interfacial resistance. As a result, by using this inorganic solid electrolyte-containing composition as a constituent layer forming material, a constituent layer with a flat surface that binds solid particles together can be formed over time while suppressing the increase in interfacial resistance between solid particles. The inventors have discovered that it is possible to manufacture an all-solid-state secondary battery that can be formed while suppressing re-aggregation, etc. due to oxidation, suppressing an increase in battery resistance, and achieving excellent cycle characteristics.
The present invention was completed after further studies based on these findings.

That is, the above problem was solved by the following means.
<1> An inorganic solid electrolyte-containing composition containing an inorganic solid electrolyte having ion conductivity of a metal belonging to Group 1 or Group 2 of the Periodic Table, a component constituting a polymer binder, and a dispersion medium. hand,
An inorganic solid electrolyte-containing composition in which a component constituting a polymer binder contains a compound defined in at least one of the following (C1) to (C3).
(C1) A polymer C1-1 having at least one type of hydrogen bonding group (BHa) in a side chain capable of forming two or more hydrogen bonds, and a polymer C1-1 having an active hydrogen atom and containing this active hydrogen atom to form a hydrogen bond. Compound C1-2 having a hydrogen bonding group (BHb) capable of forming a hydrogen bond with a hydrogen bonding group (BHa) and having a CLogP value of 1.5 or more
(C2) A polymer having two or more types of hydrogen-bonding groups (BHa) capable of forming two or more hydrogen bonds in its side chain, and having an SP value of 22.5 or less. Polymer C2
(C3) Two or more of the above polymers C1-1, or one or more of the above polymers C1-1 and one or more of the above polymers C2
<2> The inorganic solid electrolyte-containing composition according to <1>, wherein the polymer C1-1 or C2 has a component derived from a (meth)acrylic monomer or a vinyl monomer.
<3> The inorganic solid electrolyte-containing composition according to <2>, wherein the hydrogen bonding group (BHa) is introduced into the constituent components.
<4> The inorganic solid electrolyte-containing composition according to any one of <1> to <3>, wherein the inorganic solid electrolyte is a sulfide-based inorganic solid electrolyte.
<5> The inorganic solid electrolyte-containing composition according to any one of <1> to <4>, wherein the dispersion medium contains at least one selected from ketone compounds, aliphatic compounds, and ester compounds.
<6> The inorganic solid electrolyte-containing composition according to any one of <1> to <5>, which contains an active material.
<7> The inorganic solid electrolyte-containing composition according to any one of <1> to <6>, which contains a conductive aid.
<8> An all-solid-state secondary battery sheet having a layer made of the inorganic solid electrolyte-containing composition according to any one of <1> to <7> above.
<9> An all-solid-state secondary battery comprising a positive electrode active material layer, a solid electrolyte layer, and a negative electrode active material layer in this order,
At least one layer of the positive electrode active material layer, the solid electrolyte layer, and the negative electrode active material layer is a layer composed of the inorganic solid electrolyte-containing composition according to any one of <1> to <7> above. solid state secondary battery.
<10> A method for manufacturing an all-solid-state secondary battery sheet, which comprises forming a film from the inorganic solid electrolyte-containing composition according to any one of <1> to <7> above.
<11> A method for manufacturing an all-solid-state secondary battery, which comprises manufacturing an all-solid-state secondary battery through the manufacturing method described in <10> above.

The present invention is an inorganic solid electrolyte-containing composition with excellent dispersion stability and surface smoothness, which can be used as a constituent layer forming material of an all-solid-state secondary battery to further suppress increases in battery resistance (ion conductivity It is possible to provide an inorganic solid electrolyte-containing composition that can realize (increase in the amount of carbon dioxide) and excellent cycle characteristics. Moreover, the present invention can provide an all-solid-state secondary battery sheet and an all-solid-state secondary battery having a layer made of this inorganic solid electrolyte-containing composition. Furthermore, the present invention can provide a sheet for an all-solid-state secondary battery and a method for manufacturing an all-solid-state secondary battery using this inorganic solid electrolyte-containing composition.
The above and other features and advantages of the present invention will become more apparent from the following description, with appropriate reference to the accompanying drawings.

1 is a vertical cross-sectional view schematically showing an all-solid-state secondary battery according to a preferred embodiment of the present invention. FIG. 2 is a vertical cross-sectional view schematically showing a coin-type all-solid-state secondary battery produced in an example. FIG. 3 is a diagram illustrating the layer thickness measurement locations in the surface smoothness test in Examples.

In the present invention, a numerical range expressed using "~" means a range that includes the numerical values written before and after "~" as lower and upper limits.
In the present invention, the expression of a compound (for example, when it is referred to with the suffix "compound") is used to include the compound itself, its salt, and its ion. The term also includes derivatives that have been partially changed, such as by introducing a substituent, within a range that does not impair the effects of the present invention.
In the present invention, (meth)acrylic means one or both of acrylic and methacrylic. The same applies to (meth)acrylate.
In the present invention, substituents, linking groups, etc. (hereinafter referred to as substituents, etc.) that do not specify whether they are substituted or unsubstituted mean that they may have an appropriate substituent. Therefore, in the present invention, even if it is simply described as a YYY group, this YYY group includes not only an embodiment having no substituent but also an embodiment having a substituent. This also applies to compounds that do not specify whether they are substituted or unsubstituted. Preferred substituents include, for example, substituent Z described below.
In the present invention, when there are multiple substituents, etc. indicated by specific symbols, or when multiple substituents, etc. are specified simultaneously or alternatively, each substituent, etc. may be the same or different from each other. It means that. Further, even if not specified otherwise, when a plurality of substituents are adjacent to each other, it is meant that they may be connected to each other or condensed to form a ring.
In the present invention, the term "polymer" refers to a polymer, and has the same meaning as a so-called high molecular compound. Moreover, a polymer binder means a binder composed of a polymer, and includes the polymer itself and a binder formed by containing the polymer. In the present invention, the polymer binder is formed from binder components described below, and in the case of binder component (C1), the polymer binder may or may not contain compound C1-2.

[Inorganic solid electrolyte-containing composition]
The inorganic solid electrolyte-containing composition of the present invention contains an inorganic solid electrolyte having conductivity for metal ions belonging to Group 1 or 2 of the periodic table, a binder component, and a dispersion medium.
The binder component contained in the inorganic solid electrolyte-containing composition constitutes a polymer binder in the constituent layer formed of the inorganic solid electrolyte-containing composition, and contains the inorganic solid electrolyte (and the active material that may coexist). , conductive aid) and the like (for example, inorganic solid electrolytes, inorganic solid electrolytes and active materials, and active materials). Furthermore, it may function as a binder that binds the current collector and solid particles.
In the inorganic solid electrolyte-containing composition, the binder component contains a compound or a combination of compounds defined in at least one of the following (C1) to (C3). In the present invention, each compound defined in any one of (C1) to (C3) can be combined as appropriate, but it is also possible to include a compound defined in any one of (C1) to (C3) or a combination of compounds. Good.

(C1) A polymer C1-1 having at least one hydrogen-bonding group (BHa) capable of forming two or more hydrogen bonds in its side chain, and a polymer C1-1 having an active hydrogen atom and containing the above-mentioned hydrogen Combination of compound C1-2 with a CLogP value of 1.5 or more, which has a hydrogen bonding group (BHb) that can form a hydrogen bond with a binding group (BHa) (C2) Hydrogen that can form two or more hydrogen bonds Polymer C2 which is a polymer having two or more types of binding groups (BHa) in the side chain and has an SP value of 22.5 or less
(C3) A combination of two or more polymers C1-1 or one or more polymers C1-1 and one or more polymers C2

In the inorganic solid electrolyte-containing composition, the binder component and the polymer binder may or may not have the function of binding solid particles together.

The inorganic solid electrolyte-containing composition of the present invention is preferably a slurry in which the inorganic solid electrolyte is dispersed in a dispersion medium. In the inorganic solid electrolyte-containing composition, the binder component defined by any one of (C1) to (C3) above exhibits solubility (solubility) in the dispersion medium contained in the inorganic solid electrolyte-containing composition, and It is dissolved in the dispersion medium in the solid electrolyte-containing composition.
In the present invention, when the binder component is dissolved in the dispersion medium, it means, for example, that the solubility is 50% or more in solubility measurement. The method for measuring the solubility of the binder components is as follows.
That is, approximately 0.1 g of the binder component (solid) is accurately weighed, and the accurately weighed mass is defined as W0. Next, the binder components and 10 g of the dispersion medium are placed in a container and mixed for 48 hours at 25° C. and 100 rpm using a mix rotor (model number VMR-5, manufactured by As One Corporation). Thereafter, the insoluble matter is filtered from the solution, the obtained solid is vacuum dried at 120° C. for 3 hours, and the mass W1 of the insoluble matter is precisely weighed. Then, the value calculated according to the following formula is defined as the solubility (%) of the binder component in the dispersion medium.
Solubility (%) = (W0-W1)/W0×100

The binder component dissolved in the inorganic solid electrolyte-containing composition has the function of adsorbing onto solid particles such as the inorganic solid electrolyte and dispersing it in the dispersion medium. Thereby, the dispersion stability and surface smoothness (also sometimes referred to as dispersion characteristics) of the inorganic solid electrolyte-containing composition can be improved. Here, the adsorption of the binder component onto solid particles includes not only physical adsorption but also chemical adsorption (adsorption due to chemical bond formation, adsorption due to transfer of electrons, etc.).

The inorganic solid electrolyte-containing composition of the present invention has excellent dispersion stability and surface smoothness. By using this inorganic solid electrolyte-containing composition as a constituent layer forming material, an all-solid-state secondary battery sheet with a constituent layer with a flat surface and excellent surface properties, and an all-solid-state sheet with low resistance and excellent cycle characteristics. A secondary battery can be realized.
In the embodiment in which the active material layer formed on the current collector is formed using the inorganic solid electrolyte-containing composition of the present invention, the adhesiveness between the current collector and the active material layer is excellent, and further improvement in cycle characteristics is achieved. can be achieved.

Although the details of the reason are not yet clear, it is thought to be as follows.
That is, in an inorganic solid electrolyte-containing composition, the polymer C1-1 contained in the binder component is usually not completely dissolved in the dispersion medium because the hydrogen-bonding group (BHa) tends to form hydrogen bonds within the molecule. do not. However, when a compound C1-2 or a polymer (different type of polymer C1-1 or polymer C2, etc.) that can form a hydrogen bond coexists with polymer C1-1, the intramolecular hydrogen bond of polymer C1-1 is It is considered that the polymer C1-1 is partially cut and an intermolecular hydrogen bond is formed between the polymer C1-1 and the compound or polymer. In addition, since the SP value of polymer C2 contained in the binder component is 22.5 or less, hydrogen bonding groups easily form hydrogen bonds between molecules in the inorganic solid electrolyte-containing composition, and the dispersion medium It is thought that the solubility in It is believed that the polymers C1-1 and C2, which have formed intermolecular hydrogen bonds in this way, have increased solubility in the dispersion medium and are dissolved in the dispersion medium, and are appropriately adsorbed onto the solid particles while maintaining their dissolved state in the dispersion medium. It will be done. As a result, it is possible to suppress reagglomeration or sedimentation of the inorganic solid electrolyte not only immediately after preparation of the inorganic solid electrolyte-containing composition but also after time, and to stably maintain the high degree of dispersibility immediately after preparation (dispersion stability It also suppresses excessive increases in viscosity, exhibits good fluidity, and achieves a flat coating surface (excellent handling).

On the other hand, when a constituent layer is formed using the inorganic solid electrolyte-containing composition of the present invention, the polymer C1-1 It is considered that the intermolecular hydrogen bond formed at C2 is broken and an intramolecular hydrogen bond is formed instead. As intramolecular hydrogen bonds are formed, each polymer can no longer maintain its solubility in the dispersion medium and solidifies or precipitates to form a polymer binder, which partially covers the surface of the solid particle instead of completely covering it. It is thought to be coated (adsorbed). As a result, contact between solid particles is not inhibited by the presence of the polymer binder, and an ion conduction path is sufficiently established through contact between solid particles (suppressing increase in interfacial resistance between solid particles). Can be tied together.
Furthermore, the inorganic solid electrolyte-containing composition of the present invention can maintain dispersion characteristics even during film formation of the constituent layers, suppressing variations in the contact state of solid particles in the constituent layers (dispersion of solid particles in the constituent layers), and suppressing variations in the contact state of solid particles in the constituent layers. It is thought that uniform contact (adhesion) of solid particles can be ensured by making the solid particles uniform. In addition, the inorganic solid electrolyte-containing composition is easy to form into a film, and the inorganic solid electrolyte-containing composition moderately flows (leveling) during film formation, resulting in uneven surfaces caused by insufficient or excessive flow. This results in a constituent layer (with excellent flatness of the film-formed surface) that is free of surface roughness caused by clogging of the discharge section during film-forming. In this way, it is believed that an all-solid-state secondary battery sheet having a flat surface (uniform layer thickness) and low resistance (high conductivity) constituent layers can be realized.

An all-solid-state secondary battery equipped with constituent layers exhibiting the above characteristics exhibits excellent cycle characteristics even after repeated charging and discharging under normal conditions.
By the way, in all-solid-state secondary batteries for electric vehicles, due to high-output charging and discharging (high-speed charging and discharging) aimed at practical use, further increases in battery resistance and deterioration of cycle characteristics become early and noticeable. However, the all-solid-state secondary battery of the present invention enables high-speed charging and discharging with a large current in addition to charging and discharging under normal conditions. Furthermore, even during high-speed charging and discharging, the generation of voids due to expansion and contraction of the active material etc. is effectively suppressed, and excellent cycle characteristics can be achieved.

When an active material layer is formed using the inorganic solid electrolyte-containing composition of the present invention, the constituent layer is formed while maintaining a highly (uniform) dispersed state immediately after preparation, as described above. Therefore, the contact (adhesion) of the polymer binder to the current collector surface is not inhibited by preferentially settling solid particles, and the polymer binder comes into contact (adhesion) with the current collector surface in a state where the solid particles are dispersed. It seems possible. Thereby, an electrode sheet for an all-solid-state secondary battery in which an active material layer is formed on a current collector using the inorganic solid electrolyte-containing composition of the present invention can realize strong adhesion between the current collector and the active material. In addition, an all-solid-state secondary battery in which an active material layer is formed on a current collector using the inorganic solid electrolyte-containing composition of the present invention exhibits strong adhesion between the current collector and the active material, resulting in improved cycle characteristics and conductivity. Further improvements can be achieved.

The inorganic solid electrolyte-containing composition of the present invention is a forming material ( It can be preferably used as a constituent layer forming material). In particular, it can be preferably used as a material for forming a negative electrode active material layer or a negative electrode sheet for an all-solid-state secondary battery containing a negative electrode active material that expands and contracts significantly during charging and discharging, and in this embodiment also has high cycle characteristics and high conductivity. can be achieved.

The inorganic solid electrolyte-containing composition of the present invention is preferably a non-aqueous composition. In the present invention, the non-aqueous composition includes not only a form containing no water but also a form in which the water content (also referred to as water content) is preferably 500 ppm or less. In the non-aqueous composition, the water content is more preferably 200 ppm or less, even more preferably 100 ppm or less, and particularly preferably 50 ppm or less. When the inorganic solid electrolyte-containing composition is a nonaqueous composition, deterioration of the inorganic solid electrolyte can be suppressed. The water content indicates the amount of water contained in the inorganic solid electrolyte-containing composition (mass ratio to the inorganic solid electrolyte-containing composition), and specifically, it is filtered with a 0.02 μm membrane filter, This is the value measured using titration.

In addition to the inorganic solid electrolyte, the inorganic solid electrolyte-containing composition of the present invention also includes an embodiment containing an active material, a conductive aid, etc. (the composition of this embodiment is referred to as an electrode composition).
Hereinafter, the components contained and the components that can be contained in the inorganic solid electrolyte-containing composition of the present invention will be explained.

<Inorganic solid electrolyte>
The inorganic solid electrolyte-containing composition of the present invention contains an inorganic solid electrolyte.
In the present invention, the inorganic solid electrolyte refers to an inorganic solid electrolyte, and the solid electrolyte refers to a solid electrolyte that can move ions within it. Because it does not contain organic substances as the main ion-conducting material, organic solid electrolytes (polymer electrolytes such as polyethylene oxide (PEO), organic materials such as lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)) It is clearly distinguished from electrolyte salts). Furthermore, since the inorganic solid electrolyte is solid in a steady state, it is not normally dissociated or liberated into cations and anions. In this respect, it is clearly distinguishable from inorganic electrolyte salts (LiPF ₆ , LiBF ₄ , lithium bis(fluorosulfonyl)imide (LiFSI), LiCl, etc.) that are dissociated or liberated into cations and anions in electrolytes or polymers. be done. The inorganic solid electrolyte is not particularly limited as long as it has conductivity for metal ions belonging to Group 1 or Group 2 of the periodic table, and generally does not have electron conductivity. When the all-solid-state secondary battery of the present invention is a lithium ion battery, the inorganic solid electrolyte preferably has ion conductivity for lithium ions.
As the inorganic solid electrolyte, solid electrolyte materials commonly used in all-solid-state secondary batteries can be appropriately selected and used. For example, the inorganic solid electrolytes include (i) sulfide-based inorganic solid electrolytes, (ii) oxide-based inorganic solid electrolytes, (iii) halide-based inorganic solid electrolytes, and (iv) hydride-based inorganic solid electrolytes. Sulfide-based inorganic solid electrolytes are preferred from the viewpoint of being able to form a better interface between the active material and the inorganic solid electrolyte.

(i) Sulfide-based inorganic solid electrolyte Sulfide-based inorganic solid electrolytes contain sulfur atoms, have the ionic conductivity of metals belonging to Group 1 or 2 of the periodic table, and are electronically insulating. It is preferable that the material has a certain property. The sulfide-based inorganic solid electrolyte preferably contains at least Li, S, and P as elements and has lithium ion conductivity, but depending on the purpose or case, other materials other than Li, S, and P may be used. May contain elements.

Examples of the sulfide-based inorganic solid electrolyte include a lithium ion conductive inorganic solid electrolyte that satisfies the composition represented by the following formula (S1).

L _a1 M _b1 P _c1 S _d1 A _e1 (S1)

In the formula, L represents an element selected from Li, Na and K, with Li being preferred. M represents an element selected from B, Zn, Sn, Si, Cu, Ga, Sb, Al, and Ge. A represents an element selected from I, Br, Cl and F. a1 to e1 indicate the composition ratio of each element, and a1:b1:c1:d1:e1 satisfies 1 to 12:0 to 5:1:2 to 12:0 to 10. a1 is preferably 1 to 9, more preferably 1.5 to 7.5. b1 is preferably 0 to 3, more preferably 0 to 1. d1 is preferably 2.5 to 10, more preferably 3.0 to 8.5. e1 is preferably 0 to 5, more preferably 0 to 3.

The composition ratio of each element can be controlled by adjusting the blending amount of the raw material compounds when producing the sulfide-based inorganic solid electrolyte, as described below.

The sulfide-based inorganic solid electrolyte may be amorphous (glass) or crystallized (glass-ceramic), or only partially crystallized. For example, Li-P-S glass containing Li, P, and S, or Li-P-S glass ceramic containing Li, P, and S can be used.
Sulfide-based inorganic solid electrolytes include, for example, lithium sulfide (Li ₂ S), phosphorus sulfide (e.g. diphosphorus pentasulfide (P ₂ S ₅ )), elemental phosphorus, elemental sulfur, sodium sulfide, hydrogen sulfide, lithium halide (e.g. LiI, LiBr, LiCl) and sulfides of the elements represented by M (for example, SiS ₂ , SnS, GeS ₂ ) can be produced by reacting at least two raw materials.

The ratio of Li ₂ S to P ₂ S ₅ in Li-P-S glass and Li-P-S glass ceramics is a molar ratio of Li ₂ S:P ₂ S ₅ , preferably 60:40 to 60:40. The ratio is 90:10, more preferably 68:32 to 78:22. By setting the ratio of Li ₂ S to P ₂ S ₅ within this range, lithium ion conductivity can be made high. Specifically, the lithium ion conductivity can be preferably set to 1×10 ⁻⁴ S/cm or higher, more preferably 1×10 ⁻³ S/cm or higher. Although there is no particular upper limit, it is practical to set it to 1×10 ⁻¹ S/cm or less.

Examples of combinations of raw materials are shown below as specific examples of sulfide-based inorganic solid electrolytes. For example, Li ₂ SP ₂ S ₅ , Li ₂ SP ₂ S ₅ -LiCl, Li ₂ SP ₂ S ₅ -H ₂ S, Li ₂ SP ₂ S ₅ -H ₂ S-LiCl, Li ₂ S-LiI-P ₂ S ₅ , Li ₂ S-LiI-Li ₂ OP ₂ S ₅ , Li ₂ S-LiBr-P ₂ S ₅ , Li ₂ S-Li ₂ OP ₂ S ₅ , Li ₂ S-Li ₃ PO ₄ -P ₂ S ₅ , Li ₂ S-P ₂ S ₅ -P ₂ O ₅ , Li ₂ S-P ₂ S ₅ -SiS ₂ , Li ₂ S-P ₂ S ₅ -SiS ₂ -LiCl, Li ₂ S-P ₂ S ₅ -SnS, Li ₂ S-P ₂ S ₅ -Al ₂ S ₃ , Li ₂ S-GeS ₂ , Li ₂ S-GeS ₂ -ZnS, Li ₂ S-Ga ₂ S ₃ , Li ₂ S-GeS ₂ -Ga ₂ S ₃ , Li ₂ S-GeS ₂ -P ₂ S ₅ , Li ₂ S-GeS ₂ -Sb ₂ S ₅ , Li ₂ S-GeS ₂ -Al ₂ S ₃ , Li ₂ S-SiS ₂ , Li ₂ S-Al ₂ S ₃ , Li ₂ S-SiS ₂ -Al ₂ S ₃ , Li ₂ S-SiS ₂ -P ₂ S ₅ , Li ₂ S-SiS ₂ -P Examples include ₂ S ₅ -LiI, Li ₂ S-SiS ₂ -LiI, Li ₂ S-SiS ₂ -Li ₄ SiO ₄ , Li ₂ S-SiS ₂ -Li ₃ PO ₄ and Li ₁₀ GeP ₂ S ₁₂ . However, the mixing ratio of each raw material does not matter. An example of a method for synthesizing a sulfide-based inorganic solid electrolyte material using such a raw material composition is an amorphization method. Examples of the amorphization method include a mechanical milling method, a solution method, and a melt quenching method. This is because processing at room temperature becomes possible and the manufacturing process can be simplified.

(ii) Oxide-based inorganic solid electrolyte Oxide-based inorganic solid electrolytes contain oxygen atoms, have the ionic conductivity of metals belonging to Group 1 or 2 of the periodic table, and are electronically insulating. It is preferable that the material has a certain property.
The ionic conductivity of the oxide-based inorganic solid electrolyte is preferably 1×10 ⁻⁶ S/cm or more, more preferably 5×10 ⁻⁶ S/cm or more, and 1×10 ⁻⁵ S It is particularly preferable that it is at least /cm. Although the upper limit is not particularly limited, it is practical that it is 1×10 ⁻¹ S/cm or less.

Specific examples of compounds include, for example, Li _xa La _ya TiO ₃ [xa satisfies 0.3≦xa≦0.7, and ya satisfies 0.3≦ya≦0.7. ] (LLT); Li _xb La _yb Zr _zb M ^bb _{mb Onb} (M ^bb is one or more elements selected from Al, Mg, Ca, Sr, V, Nb, Ta, Ti, Ge, In and Sn Yes. ); Li _{xc Byc} M ^cc _zc O _nc (M ^cc is one or more elements selected from C, S, Al, Si, Ga, Ge, In, and Sn. xc is 0<xc≦5 yc satisfies 0<yc≦1, zc satisfies 0<zc≦1, and nc satisfies 0<nc≦6.); Li _xd (Al, Ga) _yd (Ti, Ge) _zd Si _ad P _md O _nd (xd satisfies 1≦xd≦3, yd satisfies 0≦yd≦1, zd satisfies 0≦zd≦2, ad satisfies 0≦ad≦1, md satisfies 1≦ md≦7, nd satisfies 3≦nd≦13); Li _(3-2xe) ^Mee _xe D ^ee O (xe represents a number from 0 to 0.1, and M ^ee represents a divalent Represents a metal ^atom.Dee represents a halogen atom or _a combination _of two or more halogen atoms) _; , zf satisfies 1≦zf≦10); Li _xg S _yg O _zg (xg satisfies 1≦xg≦3, yg satisfies 0<yg≦2, and zg satisfies 1≦zg≦10. ); Li ₃ BO ₃ ; Li ₃ BO ₃ -Li ₂ SO ₄ ; Li ₂ O-B ₂ O ₃ -P ₂ O ₅ ; Li ₂ O-SiO ₂ ; Li ₆ BaLa ₂ Ta ₂ O ₁₂ ; Li ₃ PO _(4-3/2w) N _w (w<1); Li _3.5 Zn _0.25 GeO ₄ having a LISICON (Lithium super ionic conductor) type crystal structure; La _0.55 having a perovskite type crystal structure Li _0.35 TiO ₃ ; LiTi ₂ P ₃ O ₁₂ having a NASICON (Natrium super ionic conductor) type crystal structure; Li _1+xh+yh (Al, Ga) _xh (Ti, Ge) _2-xh Si _yh P _3-yh O ₁₂ (xh satisfies 0≦xh≦1, and yh satisfies 0≦yh≦1. ); Examples include Li ₇ La ₃ Zr ₂ O ₁₂ (LLZ) having a garnet-type crystal structure.
Also desirable are phosphorus compounds containing Li, P and O. For example, lithium phosphate (Li ₃ PO ₄ ); LiPON in which a part of the oxygen element of lithium phosphate is replaced with a nitrogen element; LiPOD ¹ (D ¹ is preferably Ti, V, Cr, Mn, Fe, Co, One or more elements selected from Ni, Cu, Zr, Nb, Mo, Ru, Ag, Ta, W, Pt, and Au.
Furthermore, LiA ¹ ON (A ¹ is one or more elements selected from Si, B, Ge, Al, C, and Ga) can also be preferably used.

(iii) Halide-based inorganic solid electrolyte The halide-based inorganic solid electrolyte contains a halogen atom, has ion conductivity of a metal belonging to Group 1 or Group 2 of the periodic table, and has electron conductivity. Compounds having insulating properties are preferred.
Examples of the halide-based inorganic solid electrolyte include, but are not particularly limited to, compounds such as LiCl, LiBr, LiI, Li ₃ YBr ₆ and Li ₃ YCl ₆ described in ADVANCED MATERIALS, 2018, 30, 1803075. Among them, Li ₃ YBr ₆ and Li ₃ YCl ₆ are preferred.

(iv) Hydride-based inorganic solid electrolyte The hydride-based inorganic solid electrolyte contains hydrogen atoms, has the ionic conductivity of a metal belonging to Group 1 or Group 2 of the periodic table, and is electronically insulating. Compounds having properties are preferred.
Examples of the hydride-based inorganic solid electrolyte include, but are not limited to, LiBH ₄ , Li ₄ (BH ₄ ) ₃ I, 3LiBH ₄ -LiCl, and the like.

Preferably, the inorganic solid electrolyte is a particle. In this case, the average particle diameter (volume average particle diameter) of the inorganic solid electrolyte is not particularly limited, but is preferably 0.01 μm or more, more preferably 0.1 μm or more. The upper limit is preferably 100 μm or less, more preferably 50 μm or less.
The average particle diameter of the inorganic solid electrolyte is measured by the following procedure. A 1% by mass dispersion of inorganic solid electrolyte particles is prepared by diluting with water (heptane in the case of a substance unstable in water) in a 20 mL sample bottle. The diluted dispersion sample is irradiated with 1 kHz ultrasonic waves for 10 minutes, and immediately thereafter used for the test. Using this dispersion sample, data was acquired 50 times using a laser diffraction/scattering particle size distribution analyzer LA-920 (trade name, manufactured by HORIBA) at a temperature of 25°C using a quartz cell for measurement. Obtain the volume average particle size. For other detailed conditions, refer to the description in Japanese Industrial Standards (JIS) Z 8828:2013 "Particle Size Analysis - Dynamic Light Scattering Method" if necessary. Five samples are prepared for each level and the average value is used.

The inorganic solid electrolyte may contain one type or two or more types.
When forming a solid electrolyte layer, the mass (mg) (basis weight) of the inorganic solid electrolyte per unit area (cm ² ) of the solid electrolyte layer is not particularly limited. It can be determined as appropriate depending on the designed battery capacity, and can be, for example, 1 to 100 mg/cm ² .
However, when the inorganic solid electrolyte-containing composition contains the active material described below, the basis weight of the inorganic solid electrolyte is preferably such that the total amount of the active material and the inorganic solid electrolyte is within the above range.

The content of the inorganic solid electrolyte in the inorganic solid electrolyte-containing composition is not particularly limited, but it should be 50% by mass or more based on 100% by mass of solids in terms of binding and dispersibility. is preferable, more preferably 70% by mass or more, and particularly preferably 90% by mass or more. From the same viewpoint, the upper limit is preferably 99.9% by mass or less, more preferably 99.5% by mass or less, and particularly preferably 99% by mass or less.
However, when the inorganic solid electrolyte-containing composition contains the active material described below, the content of the inorganic solid electrolyte in the inorganic solid electrolyte-containing composition is such that the total content of the active material and the inorganic solid electrolyte is within the above range. It is preferable.
In the present invention, the solid content (solid component) refers to a component that does not disappear by volatilization or evaporation when the inorganic solid electrolyte-containing composition is dried at 150°C for 6 hours under an atmospheric pressure of 1 mmHg and a nitrogen atmosphere. . Typically, it refers to components other than the dispersion medium described below.

<Polymer binder and binder components>
As mentioned above, the inorganic solid electrolyte-containing composition of the present invention contains at least one of the compounds specified in (C1) to (C3) below as a component constituting the polymer binder that functions as a binder in the constituent layers. or a combination of compounds. In the present invention, when it is said that the inorganic solid electrolyte-containing composition contains a binder component, it includes an embodiment in which a part of the binder component forms a polymer binder.

(polymer binder)
The binder component forms a polymer binder during film formation of the inorganic solid electrolyte-containing composition. This is thought to be due to the selective formation of intramolecular hydrogen bonds in polymer C1-1 or C2. The polymer binder contained in the constituent layer thus formed can be said to be an (intramolecular) hydrogen bond of polymer C1-1 or C2 defined by any one of (C1) to (C3). The polymer binder is not uniquely determined by the type of compound defined by any of (C1) to (C3), the type or combination of hydrogen bonding groups, etc., and in the present invention, (meth) Hydrogen bonds of acrylic polymers or vinyl polymers are preferred.
Polymer C1-1 or C2 having a hydrogen-bonding group (BHa) has a lower solubility in a dispersion medium as the number of intramolecular hydrogen bonds formed increases, and a decrease in solubility in a dispersion medium as the number of intermolecular hydrogen bonds formed increases. It is thought that the sex will increase. Therefore, in the present invention, the solubility in the dispersion medium can be controlled by increasing or decreasing the amount of intramolecular hydrogen bonds of the polymer C1-1 or C2. Thereby, it is possible to improve the dispersion characteristics of the inorganic solid electrolyte-containing composition, and to suppress the binding function between the solid particles in the constituent layers and the increase in interfacial resistance.
The constituent layer may contain one kind or two or more kinds of polymer binders.
In the present invention, when a constituent layer contains a polymer binder, it includes an embodiment in which the constituent layer contains (remains) a binder constituent component.

(Components constituting the polymer binder)
The binder component is at least one of a combination of compounds defined in (C1) below, a compound defined in (C2), and a combination of compounds defined in (C3) below.

(C1) A polymer C1-1 having at least one type of hydrogen bonding group (BHa) in a side chain capable of forming two or more hydrogen bonds, and a hydrogen bonding group (BHb) having an active hydrogen atom, Combination with compound C1-2 having a CLogP value of 1.5 or more and having a hydrogen-bonding group (BHb) that contains an active hydrogen atom and can form a hydrogen bond with the hydrogen-bonding group (BHa) of a polymer (C1 ), the compound C1-2 easily forms an intermolecular hydrogen bond with the polymer C1-1 in the inorganic solid electrolyte-containing composition (dispersion medium) and dissolves in the dispersion medium. In this respect, compound C1-2 can be referred to as a compatibilizer for polymer C1-1.

(C2) A polymer having two or more types of hydrogen-bonding groups (BHa) capable of forming two or more hydrogen bonds in its side chain, and having an SP value of 22.5 or less. Polymer C2

(C3) Two or more polymers C1-1, or one or more polymers C1-1 and one or more polymers C2

First, the binder component (C1) will be explained.
- Polymer C1-1 -
Polymer C1-1 has at least one hydrogen bonding group (BHa) capable of forming two or more hydrogen bonds in its side chain.
The hydrogen-bonding group (BHa) is not particularly limited as long as it is a substituent or a linking group that can form two or more hydrogen bonds. This hydrogen bonding group (BHa) has an acceptor site (unshared electron pair) that accepts a hydrogen atom and a donor site (a hydrogen atom capable of hydrogen bonding) that supplies a hydrogen atom within one substituent (linking group). Preferably, at least one of the hydrogen-bonding groups (BHa) is a group containing at least one acceptor site and at least one donor site.

The hydrogen-bonding group (BHa) usually forms a hydrogen bond with another hydrogen-bonding group (BHa) or the hydrogen-bonding group (BHb) of compound C1-2, which will be described later. A portion of the hydrogen bonding groups (BHa) may form a hydrogen bond within one group as long as it does not cause any damage.

The number of hydrogen bonds that can be formed by the hydrogen bonding group (BHa) may be 2 or more, and from the viewpoint of ease of forming hydrogen bonds, it is preferably 3 or more, and 4 or more is preferable. More preferred. The upper limit is not particularly limited, but is practically 10 or less, and is preferably 5 or less in terms of increasing solubility in the inorganic solid electrolyte-containing composition.
The total number of acceptor sites and donor sites that the hydrogen-bonding group (BHa) has is usually synonymous with the number of hydrogen bonds that the hydrogen-bonding group (BHa) can form.

The combination of the acceptor site and the donor site that the hydrogen-bonding group (BHa) has is not particularly limited and is determined as appropriate, but it includes both an acceptor site and a donor site in that it can form a strong hydrogen bond. Combinations are preferred, and combinations in which acceptor sites (excluding heteroatoms to which hydrogen atoms in donor sites are covalently bonded) and donor sites are arranged alternately in the molecular chain constituting the hydrogen-bonding group (for example, urea groups, urethane groups) ) is more preferable.

The acceptor site (unshared electron pair) is not particularly limited, but includes, for example, the oxygen atom of a carbonyl group (>C=O), the sulfur atom of a thiocarbonyl group (>C=S), an enamine, or a heterocyclic ring. =N-, furthermore, ether groups (including hydroxyl groups), amino groups or thioether groups (including sulfanyl groups (-SH)) have oxygen atoms, nitrogen atoms or sulfur atoms, phosphoric acid groups, etc. =P- Among them, the above =N-, the oxygen atom in each of the above groups, and the nitrogen atom in each of the above groups are preferable in terms of forming stronger hydrogen bonds with hydrogen atoms.

The donor site is not particularly limited, and includes a hydrogen atom capable of hydrogen bonding, usually a hydrogen atom (active hydrogen atom) bonded to a heteroatom such as oxygen or nitrogen. Examples include a hydrogen atom covalently bonded to a nitrogen atom, a hydrogen atom covalently bonded to an oxygen atom, a hydrogen atom covalently bonded to a sulfur atom, a hydrogen atom covalently bonded to a phosphorus atom, and the like. Among these, a hydrogen atom covalently bonded to a nitrogen atom or a hydrogen atom covalently bonded to an oxygen atom is preferred in terms of forming a stronger hydrogen bond with an acceptor site.
Here, the nitrogen atom to which a hydrogen atom is covalently bonded is not limited to a primary or secondary amino group, but if a hydrogen atom is covalently bonded, it is included in a functional group such as a urethane group or a urea group. This includes nitrogen atoms. The same applies to phosphorus atoms.

Examples of the hydrogen-bonding group (BHa) include a group formed by appropriately combining an acceptor site and a donor site. As the acceptor site, a combination of an oxygen atom of a carbonyl group (>C=O) and a donor site is preferred.
Specific examples of hydrogen-bonding groups (BHa) include, but are not limited to, acidic groups such as hydroxyl groups and carboxy groups, sulfanyl groups, primary or secondary amino groups, primary or secondary amide groups (amide bonds, : -CO-NR ^a -), urethane group (urethane bond: -O-CO-NR ^a - included), urea group (urea bond: -NR ^a -CO-NR ^{a -} included) , a carbonate group (including a carbonate bond: -O-CO-O-), an alkylene diamine structure, and an alkylene amino ether structure. In addition to these, examples of generally well-known nucleobases (adenine and thymine/guanine and cytosine), as well as Lehn supramolecular chemistry (Kagaku Doujin, 1997; written by J-M. Lehn, translated by Keito Takeuchi) Chapter 9, pp. 145-206, Developments in Supramolecular Chemistry (Iwanami Shoten, 2000; written by Katsuhiko Ariga and Toyoshi Kunitake), Chapter 4, pp. 63-71, Chem. Rev. , 94, 2383-2420 (1994), Polym. Int. , 51, 825-839 (2002), Chem. Rev. , 101, 4071-4097 (2001) and the like. Each of the above R ^a represents a hydrogen atom or a substituent (preferably selected from substituents Z described below), and a hydrogen atom is preferable.
Among these, substituents such as hydroxyl group and sulfanyl group, substituents or linking groups (bonds) such as amide group, urethane group, and urea group are preferred.

The polymer C1-1 only needs to have at least one type of the above-mentioned hydrogen bonding group (BHa), and may have 2 to 5 types. Improving solubility in a dispersion medium by preferentially forming intermolecular hydrogen bonds in an inorganic solid electrolyte-containing composition, and reducing solubility in a dispersion medium by preferentially forming intramolecular hydrogen bonds in the film forming process. Considering this, it is preferable to use one type.
The number of hydrogen-bonding groups (BHa) that one molecule of polymer C1-1 has may be one or more, but it is preferable to have two or more since strong hydrogen bonds can be formed. The number of hydrogen-bonding groups (BHa) cannot be uniquely determined, but is appropriately determined based on the number of hydrogen-bonding groups (BHa) possessed by the hydrogen-bonding constituents and the content of the hydrogen-bonding constituents, which will be described later. be done.
This hydrogen bonding group (BHa) is present in the side chain of the polymer C1-1, and is preferably introduced into the side chain as a linking group or (terminal) substituent, and is preferably introduced into the side chain as a linking group. It is more preferable that the
In the present invention, the main chain of a polymer refers to a linear molecular chain in which all other molecular chains constituting the polymer can be considered as branched chains or pendants with respect to the main chain. Although it depends on the weight average molecular weight of the molecular chains considered as branched chains or pendant chains, typically the longest chain among the molecular chains constituting the polymer is the main chain. However, the main chain does not include the terminal group that the polymer terminal has. Moreover, the side chain of a polymer refers to a molecular chain other than the main chain, and includes short molecular chains and long molecular chains.
In the present invention, having a hydrogen bonding group (BHa) in the side chain of a polymer means that the hydrogen bonding group (BHa) is indirectly bonded to an atom constituting the main chain of the polymer, It does not include embodiments in which it is directly bonded to atoms constituting the main chain. For example, when polymer C1-1 has a component derived from a (meth)acrylic monomer, the ester bond (directly bonded to an atom constituting the main chain) of this (meth)acrylic monomer is Not included in hydrogen bonding groups (BHa). In the present invention, the main chain of the polymer may contain a hydrogen-bonding group (BHa), but it is preferable that it does not.

The group that connects the main chain of the polymer and the hydrogen-bonding group (BHa) introduced as a linking group or (terminal) substituent is not particularly limited and is appropriately selected. For example, alkylene group (carbon number is preferably 1 to 12, more preferably 1 to 6, still more preferably 1 to 3), alkenylene group (carbon number is preferably 2 to 6, more preferably 2 to 3), arylene group (preferably 6 to 24 carbon atoms, more preferably 6 to 10 carbon atoms), oxygen atom, sulfur atom, imino group (-NR ^N -: R ^N is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a carbon number 6 to 10 aryl groups), carbonyl group, phosphoric acid linking group (-O-P(OH)(O)-O-), phosphonic acid linking group (-P(OH)(O)-O- ), or a combination thereof. A polyalkyleneoxy chain can also be formed by combining an alkylene group and an oxygen atom.
The linking group is preferably a group formed by combining an alkylene group, an arylene group, a carbonyl group, an oxygen atom, a sulfur atom, and an imino group, and a group formed by a combination of an alkylene group, an arylene group, a carbonyl group, an oxygen atom, and an imino group. More preferably, a group containing a -CO-O- group, a -CO-N(R ^N )- group (R ^N is as described above), or an arylene group, a -CO-O-alkylene group, - A CO-N(R ^N )-alkylene group and the like are particularly preferred.
In the present invention, the number of atoms constituting the above-mentioned connecting group is preferably 1 to 36, more preferably 1 to 24, and even more preferably 1 to 12. The number of linked atoms in the linked groups is preferably 10 or less, more preferably 8 or less. The lower limit is 1 or more. The above-mentioned number of connected atoms refers to the minimum number of atoms connecting predetermined structural parts. For example, in the case of -C(=O)-O-CH ₂ -, the number of atoms constituting the linking group is six, but the number of linking atoms is three.
On the other hand, when a hydrogen-bonding group (BHa) is introduced as a linking group, the terminal substituent that bonds to the hydrogen-bonding group (BHa) is not particularly limited and is appropriately selected. For example, a group selected from the following substituent Z may be mentioned, and among them, an alkyl group, an aralkyl group, an aryl group, a heterocyclic group, etc. are preferably mentioned.

In addition to the hydrogen bonding group (BHa), the polymer C1-1 may have a hydrogen bonding group (acceptor site) capable of forming one hydrogen bond.

In the inorganic solid electrolyte-containing composition, the polymer C1-1 preferably has a small SP value, since it increases its solubility in the dispersion medium by improving its affinity with the dispersion medium. The value is preferably 21.0 MPa ^1/2 or less, more preferably 20.5 MPa ^1/2 or less. The lower limit is not particularly limited, but for example, it is preferably 13.0 MPa ^1/2 or more, more preferably 16.0 MPa ^1/2 or more, and still more preferably 18.0 MPa ^1/2 or more. preferable.

Polymer C1-1 may be a commercially available product or a synthesized product.
In the inorganic solid electrolyte-containing composition, the content of polymer C1-1 is not particularly limited, and is appropriately determined depending on dispersion characteristics, battery performance, etc. For example, the content of polymer C1-1 is from 0.1 to 10% as the total content with compound C1-2, based on solid content of 100% by mass, in terms of improvement in dispersion characteristics, resistance, and cycle characteristics. It is preferably 0% by mass, more preferably 0.2-5.0% by mass, and even more preferably 0.3-4.0% by mass.
The content of polymer C1-1 in the inorganic solid electrolyte-containing composition is not particularly limited, but in terms of improvement in dispersion characteristics, resistance, cycle characteristics, etc., the content of polymer C1-1 is 0.1 to 9 at 100% by mass solid content. It is preferably 0.9% by weight, more preferably 0.15-4.95% by weight, even more preferably 0.25-3.96% by weight. Furthermore, the mass ratio between the content of polymer C1-1 and the content of compound C1-2 [content of polymer C1-1: content of compound C1-2] is not particularly limited, but hydrogen-bonding groups ( In terms of the number of BHa) and (BHb), solubility in dispersion medium due to hydrogen bond formation, etc., the ratio is preferably 50:50 to 99:1, and preferably 70:30 to 97:3. The ratio is more preferably 85:15 to 95:5.
The above content of the polymer C1-1 is the total amount including the polymer C1-1 forming the hydrogen bond when the polymer C1-1 has a hydrogen bond with the compound C1-2.

- Compound C1-2 with a CLogP value of 1.5 or more -
This compound C1-2 has a hydrogen bonding group (BHb) that contains an active hydrogen atom and can form a hydrogen bond with the hydrogen bonding group (BHa) possessed by the polymer C1-1. The hydrogen-bonding group (BHb) possessed by this compound C1-2 is similar to the hydrogen-bonding group (BHa) in that it easily forms an intermolecular hydrogen bond with the polymer C1-1 in the inorganic solid electrolyte-containing composition. Preferably, they are different groups.
The hydrogen-bonding group (BHb) has an active hydrogen atom. This active hydrogen atom may be any hydrogen atom that can form a hydrogen bond with the above-mentioned hydrogen-bonding group (BHa), usually the above-mentioned acceptor site, and each hydrogen atom described as a donor site of the hydrogen-bonding group (BHa). A hydrogen atom covalently bonded to a nitrogen atom or an oxygen atom is preferable in terms of forming a stronger hydrogen bond with the hydrogen bonding group (BHa). The number of active hydrogen atoms that one hydrogen bonding group (BHb) has is not particularly limited, and is usually 1 to 8, preferably 1 or 2.
Examples of such a hydrogen-bonding group (BHb) having an active hydrogen atom include a group containing a nitrogen atom, an oxygen atom, a sulfur atom, or a phosphorus atom to which a hydrogen atom is covalently bonded. Examples include acidic groups such as hydroxyl groups and carboxy groups, sulfanyl groups, primary or secondary amino groups, alkylene diamine structures, and alkylene amino ether structures.
This hydrogen-bonding group (BHb) may further include the above-mentioned acceptor site, donor site, etc., and constitute the above-mentioned hydrogen-bonding group (BHa). For example, the amino group as the hydrogen-bonding group (BHb) may be an amino group constituting an amide group or a urethane group, which is the hydrogen-bonding group (BHa). Examples of the group containing such an amino group include those explained in the above-mentioned hydrogen bonding group (BHa), and specific examples thereof include a primary or secondary amide group, a urethane group, and a urea group. The hydrogen-bonding group (BHb) is preferably a hydroxyl group, an amino group, or a group containing an amino group, since it forms a strong hydrogen bond with the hydrogen-bonding group (BHa).
Compound C1-2 may have one or more hydrogen-bonding groups (BHb), but only one is preferable since it can form an efficient hydrogen bond with polymer C1-1. It is preferable.

In (C1), the combination of the hydrogen-bonding group (BHa) of the polymer C1-1 and the hydrogen-bonding group (BHb) of the compound C1-2 is not particularly limited and is appropriately set. For example, a combination of a preferable hydrogen-bonding group (BHa) and a preferable hydrogen-bonding group (BHb) is preferable, and a combination of a hydroxyl group, a urethane group, or a urea group as the hydrogen-bonding group (BHa), More preferred is a combination with a hydroxyl group, an amino group, or a group containing an amino group as a hydrogen-bonding group (BHb).

Compound C1-2 has a CLogP value of 1.5 or more. Thereby, while dissolving in the dispersion medium of the inorganic solid electrolyte-containing composition, it becomes compatible with the polymer C1-1, increasing the solubility of the polymer C1-1 in the dispersion medium, and contributing to improving the dispersion characteristics.
The CLogP value is preferably 1.7 or more, more preferably 1.9 or more, and even more preferably 2.0 or more. The upper limit is not particularly limited, but it is practical to be 12.0 or less, and preferably 6.0 or less.
In the present invention, the CLogP value is a value obtained by calculating the common logarithm LogP of the partition coefficient P between 1-octanol and water. Known methods and software can be used to calculate the CLogP value, but unless otherwise specified, the structure is drawn using ChemDraw from PerkinElmer, and the calculated value is used.
When two or more types of compounds C1-2 are contained, the ClogP value is the sum of the products of the ClogP value and the mass fraction of each compound.

Compound C1-2 is not particularly limited as long as it satisfies the ClogP value and has the above hydrogen bonding group (BHb), and may be a low molecular compound (non-polymerizable compound) or a high molecular compound. A low-molecular compound is preferable because it can effectively reinforce the improvement in dispersion properties provided by polymer C1-1.

When compound C1-2 is a low-molecular compound, this low-molecular compound is not particularly limited, and may be a compound in which the above hydrogen-bonding group (BHb) is introduced as a substituent or a linking group (bond) into an appropriate basic skeleton. Can be mentioned. Examples of low-molecular compounds include amine compounds having an amino group (including compounds in which an amino bond is introduced as a linking group), alcohol compounds having a hydroxyl group, thiol compounds having a sulfanyl group, and carboxyl compounds having a carboxy group. Examples thereof include acid compounds, sulfonic acid compounds having a sulfo group, phosphoric acid compounds having a phosphoric acid group, and phosphonic acid compounds having a phosphonic acid group. These compounds may be either aliphatic compounds or aromatic compounds, and the above-mentioned hydrogen-bonding group (BHb ) are introduced. Among these, alcohol compounds or amine compounds such as aliphatic saturated hydrocarbons, aliphatic unsaturated hydrocarbons, aromatic hydrocarbons, and aromatic heterocycles are preferable, and alcohol compounds or amine compounds of aliphatic saturated hydrocarbons are more preferable. More preferred are chain or cyclic aliphatic saturated hydrocarbon alcohol compounds or amine compounds.
The molecular weight and chemical structure of the low-molecular compound are not particularly limited as long as they satisfy the ClogP value, and can be set as appropriate. For example, the molecular weight can be 1000 or less, preferably 100-400. Furthermore, the low molecular compound may have a substituent other than the hydrogen-bonding group (BHb) as long as it satisfies the ClogP value, for example, it may have a group selected from substituents Z described below. .

As compound C1-2, a commercially available product may be used, or one synthesized by a conventional method may be used.
The inorganic solid electrolyte-containing composition of the present invention may contain one or more compounds C1-2.
The content of compound C1-2 in the inorganic solid electrolyte-containing composition is not particularly limited, and in terms of the solubility of polymer C1-1 in the dispersion medium due to the formation of hydrogen bonds, etc., at 100% by mass solid content, The amount is preferably 0.05 to 8.0% by weight, more preferably 0.10 to 4.0% by weight, and even more preferably 0.15 to 3.0% by weight.
The above content of compound C1-2 is the total amount including, when compound C1-2 forms a hydrogen bond with polymer C1, compound C1-2 forming this hydrogen bond.

The combination of polymer C1-1 and compound C1-2 is not particularly limited as long as it is a combination that can form a hydrogen bond, for example, a combination of a preferred polymer C1-1 and a preferred compound C1-2. can be mentioned.

Next, the binder component (C2) will be explained.
Polymer C2 has two or more types of hydrogen-bonding groups (BHa) capable of forming two or more hydrogen bonds in its side chains.
This polymer C2 may be the same as the polymer C1-1 having two or more types of hydrogen bonding groups (BHa).
The hydrogen-bonding group (BHa) possessed by the polymer C2 and the aspect of having this hydrogen-bonding group (BHa) in the side chain are also the same as those in the above-mentioned polymer C1-1.

Polymer C2 only needs to have at least two types of hydrogen-bonding groups (BHa), which improves solubility in a dispersion medium by preferentially forming intermolecular hydrogen bonds in an inorganic solid electrolyte-containing composition; Considering the reduction in solubility in the dispersion medium due to the preferential formation of intramolecular hydrogen bonds in the film forming process, it is preferable to have 2 to 5 types, and it is more preferable to have 2 or 3 types. preferable.
It is preferable that the two or more types of hydrogen-bonding groups (BHa) possessed by the polymer C2 are different from each other because they can form strong hydrogen bonds and effectively solidify or precipitate the polymer C2. In this case, the combination of two or more hydrogen bonding groups (BHa) is not particularly limited, and the above-mentioned combination of the hydrogen bonding group (BHa) possessed by polymer C1-1 and the hydrogen bonding group possessed by compound C1-2 is not particularly limited. The above-mentioned preferred combinations with the group (BHb) are mentioned.
The number of hydrogen-bonding groups (BHa) that one molecule of polymer C2 has may be at least one for each type of hydrogen-bonding group, but it is preferably two or more in order to form strong hydrogen bonds. It is preferable. The number of hydrogen-bonding groups (BHa) cannot be uniquely determined, but is appropriately determined based on the number of hydrogen-bonding groups (BHa) possessed by the hydrogen-bonding constituents and the content of the hydrogen-bonding constituents, which will be described later. be done.

In addition to the hydrogen bonding group (BHa), the polymer C2 may have a hydrogen bonding group capable of forming one hydrogen bond.

Polymer C2 has an SP value of 22.5 MPa ^1/2 or less according to the calculation method described below. This increases the affinity for the dispersion medium in the inorganic solid electrolyte-containing composition, and particularly when intermolecular hydrogen bonds are formed, the solubility in the dispersion medium increases and the dispersion characteristics can be improved. The SP value of the polymer C2 is preferably 21.0 MPa ^1/2 or less, more preferably 20.5 MPa ^1/2 or less. The lower limit is not particularly limited, but for example, it is preferably 13.0 MPa ^1/2 or more, more preferably 16.0 MPa ^1/2 or more, and more preferably 18.0 MPa ^1/2 or more. preferable.

The method of calculating the SP value will be explained.
(1) Calculate the SP value of the constituent unit.
First, for a polymer, a structural unit that specifies the SP value is determined.
That is, in the present invention, when calculating the SP value of a polymer, if the polymer (segment) is a chain polymerization polymer, the same structural unit as the component derived from the raw material compound is used, but if the polymer is a sequential polymerization polymer. In this case, the unit is different from the constituent components derived from the raw material compound. For example, taking polyurethane as an example of a sequentially polymerized polymer, the constituent units that specify the SP value are defined as follows. As a structural unit derived from a polyisocyanate compound, an -O- group is bonded to one -NH-CO- group, and the remaining -NH-CO- group is bonded to a constituent component derived from a polyisocyanate compound. This is the removed unit (a unit having one urethane bond). On the other hand, as a structural unit derived from a polyol compound, a -CO-NH- group is bonded to one -O- group and the remaining -O- group is removed. unit (unit having one urethane bond). In addition, in the case of other sequentially polymerized polymers, the constituent units are determined in the same manner as for polyurethane.

Next, unless otherwise specified, the SP value for each constituent unit is determined by the Hoy method (H.L.Hoy JOURNAL OF PAINT TECHNOLOGY Vol. 42, No. 541, 1970, 76-118, and POLYMER HANDBOOK 4 ^th , Chapter 59) , VII, page 686, Table 5, Table 6, and the following formula in Table 6).

(2) SP value of polymer Calculate from the following formula using the structural units determined as above and the SP value determined. In addition, the SP value of the structural unit determined according to the above literature is converted to SP value (MPa ^1/2 ) (for example, 1 cal ^1/2 cm ^-3/2 ≒ 2.05J ^1/2 cm ^{-3/ 2} ≒2.05MPa ^1/2 ).

SP _p ² = (SP ₁ ² ×W ₁ )+(SP ₂ ² ×W ₂ )+...

In the formula, SP ₁ , SP ₂ . . . represent the SP values of the structural units, and W ₁ , W ₂ .
In the present invention, the mass fraction of a structural unit is the mass fraction of a structural component corresponding to the structural unit (a raw material compound that leads to this structural component) in the polymer.

The SP value of a polymer can be adjusted depending on the type or composition of the polymer (types and contents of constituent components), and the like.

In the present invention, the SP value of the polymer is calculated using the above formula for all structural units. If the polymer contains a component derived from a macromonomer, the SP value (excluding MM) calculated by the above formula may be calculated by excluding the component corresponding to the component derived from the macromonomer (MM). can. According to the SP value (excluding MM) calculated in this way, the dispersion characteristics can be further improved. The SP value (excluding MM) can be in the same range as the above SP value, but is preferably 13.0 to 22.5 MPa ^1/2 , and preferably 16.0 to 21.0 MPa ^1/2 . More preferably, it is 17.5 to 20.5 MPa ^1/2 .

Polymer C2 may be a commercially available product or a synthesized product.
The inorganic solid electrolyte-containing composition of the present invention may contain one or more types of polymer C2.
The content of polymer C2 in the inorganic solid electrolyte-containing composition is not particularly limited, and is appropriately determined depending on dispersion characteristics, battery performance, and the like. For example, in terms of improvement in dispersion characteristics, resistance, cycle characteristics, etc., it is preferably 0.1 to 10.0% by mass, and preferably 0.2 to 5.0% by mass, based on 100% by mass of solid content. The content is more preferably 0.3 to 4.0% by mass. The above-mentioned content of the polymer C2 is the total amount including the polymer C2 forming the hydrogen bond when the polymers C2 are hydrogen bonded to each other.

Finally, the binder component (C3) will be explained.
One embodiment of (C3) is to use two or more types of polymer C1-1 in combination, and in place of the compound C1-2 used in combination with polymer C1-1 in the above (C1), another polymer C1-1 is used. Use in combination. Polymer C1-1 is as described above.
It is preferable that the two types of polymers C1-1 used in combination are different in type, such as a combination of polymers with different types or compositions and types of hydrogen bonding groups (BHa), which can form strong hydrogen bonds. A combination of different types of hydrogen-bonding groups (BHa) is more preferable.
The combination of different types of hydrogen bonding groups (BHa) is not particularly limited, and in (C1) above, the hydrogen bonding group (BHa) possessed by polymer C1-1 and the hydrogen bond possessed by compound C1-2. and a preferable combination with a functional group (BHb).

In one embodiment, the inorganic solid electrolyte-containing composition may contain at least two types of polymer C1-1, and may also include two to five types. Preferably it is 2, 3 or 4 types.
In one embodiment, the total content of polymer C1-1 in the inorganic solid electrolyte-containing composition is not particularly limited, and is appropriately determined depending on dispersion characteristics, battery performance, and the like. For example, in terms of improvement in dispersion characteristics, resistance, cycle characteristics, etc., it is preferably 0.1 to 10.0% by mass, and preferably 0.2 to 5.0% by mass, based on 100% by mass of solid content. The content is more preferably 0.3 to 4.0% by mass. The content ratio of two or more types of polymer C1-1 is not particularly limited, and depends on the number of hydrogen-bonding groups (BHa) that polymer C1-1 has, solubility in a dispersion medium due to the formation of hydrogen bonds, etc. This will be determined as appropriate. For example, when two types are used in combination, the content (mass%) ratio of one polymer to the other polymer is preferably 1:10 to 10:1, and preferably 1:5 to 5:1. is more preferable, and even more preferably 1:3 to 3:1. The content of the polymer C1-1 is the total amount including the polymer C1-1 forming hydrogen bonds when the polymers C1-1 have hydrogen bonds with each other.

Another embodiment of (C3) uses a combination of one or more polymers C1-1 and one or more polymers C2. Polymers C1-1 and C2 are as described above.
The hydrogen-bonding group (BHa) possessed by the polymer C1-1 and the hydrogen-bonding group (BHa) possessed by the polymer C2 are preferably different types in that they can form a strong hydrogen bond. The combination of different types of hydrogen bonding groups (BHa) is the same as in the above embodiment.
In another embodiment, the inorganic solid electrolyte-containing composition contains one or more types of polymers C1-1 and C2, respectively, and may include 2 to 5 types, but preferably one type.
In another embodiment, the total content of polymers C1-1 and C2 in the inorganic solid electrolyte-containing composition is not particularly limited, and is appropriately determined depending on dispersion characteristics, battery performance, etc. For example, in terms of improvement in dispersion characteristics, resistance, cycle characteristics, etc., it is preferably 0.1 to 10.0% by mass, and preferably 0.2 to 5.0% by mass, based on 100% by mass of solid content. The content is more preferably 0.3 to 4.0% by mass. In addition, the content ratio of polymer C1-1 and polymer C2 is not particularly limited, and the number of hydrogen-bonding groups (BHa) that polymers C1-1 and C2 have, the solubility in the dispersion medium due to the formation of hydrogen bonds, The ratio is determined as appropriate in consideration of the above factors, and for example, the ratio in the above-mentioned embodiment can be mentioned. The content of the polymers C1-1 and C2 is the total amount including the polymer C1-1 forming hydrogen bonds when the polymers C1-1 have hydrogen bonds with each other.

-- Polymer C1-1 and C2 --
Polymers C1-1 and C2 are the same except for the number of types of hydrogen bonding groups (BHa) mentioned above, so they will be described together.
The polymer is a polymer having the above-mentioned hydrogen-bonding group (BHa) in its side chain, and any polymer commonly used as a binder for all-solid-state secondary batteries can be used without particular limitation. Examples of such polymers include sequentially polymerized (polycondensation, polyaddition, or addition condensation) polymers such as polyurethane, polyurea, polyamide, polyimide, polyester, polyether, and polycarbonate, as well as fluoropolymers (fluorine-containing polymers). polymers), hydrocarbon polymers, vinyl polymers, (meth)acrylic polymers, and other chain polymers. Among these, vinyl polymers and (meth)acrylic polymers are preferred.
The polymer constituting the polymer preferably has a component derived from a (meth)acrylic monomer or a vinyl monomer, and a polymer having 50% by mass or more of a component derived from these monomers ((meth)acrylic polymer or vinyl polymers) are preferred.
In the present invention, when the polymer is a copolymer, the bonding mode (arrangement) of the copolymer components is not particularly limited, and it may be a random copolymer, an alternating copolymer, a block copolymer, a graft copolymer, etc. But that's fine.

The (meth)acrylic monomer includes a monomer having a (meth)acryloyloxy group or a (meth)acryloylamino group, and further includes a (meth)acrylonitrile compound. (Meth)acrylic monomers include, but are not particularly limited to, (meth)acrylic compounds (M ), among which (meth)acrylic acid ester compounds are preferred.
The (meth)acrylic acid ester compound is not particularly limited, and examples include esters of aliphatic or aromatic hydrocarbons or aliphatic or aromatic heterocyclic compounds, and these hydrocarbons, heterocyclic compounds, etc. The number of carbon atoms and the type or number of heteroatoms are not particularly limited and are set appropriately. For example, the number of carbon atoms can be 1 to 30.

The vinyl monomer is a monomer containing a vinyl group other than the (meth)acrylic compound (M), and is not particularly limited, but includes, for example, a vinyl group-containing aromatic compound (styrene compound, vinylnaphthalene compound, etc.), a vinyl group-containing monomer Heterocyclic compounds (vinylcarbazole compounds, vinylpyridine compounds, vinylimidazole compounds, vinyl group-containing aromatic heterocyclic compounds such as N-vinylcaprolactam, vinyl group-containing non-aromatic heterocyclic compounds, etc.), allyl compounds, vinyl ether compounds, vinyl ketones Examples thereof include vinyl compounds such as vinyl ester compounds, dialkyl itaconate compounds, and unsaturated carboxylic acid anhydrides. Examples of vinyl compounds include "vinyl monomers" described in JP-A No. 2015-88486.

As a (meth)acrylic monomer, the polymer is a (meth)acrylic acid ester compound containing an aliphatic hydrocarbon (preferably an alkyl) having 4 or more carbon atoms in order to express or improve solubility in a dispersion medium. It is preferable to have a component derived from a meth)acrylic acid ester compound. The number of carbon atoms in the aliphatic hydrocarbon group is preferably 6 or more, more preferably 10 or more. The upper limit is not particularly limited, and is preferably 20 or less, more preferably 14 or less. The aliphatic hydrocarbon having 4 or more carbon atoms may have a branched structure or a cyclic structure, but preferably has a linear structure. As the (meth)acrylic monomer into which the hydrogen-bonding group (BHa) is introduced, among (meth)acrylic ester compounds, (meth)acrylic esters of aliphatic hydrocarbons (preferably alkyl) having 3 or less carbon atoms are used. Preferably, it is a compound.
The polymer preferably has a constituent component derived from a styrene compound as a vinyl monomer, from the viewpoint of resistance and cycle characteristics, as well as improving the strength of the polymer binder, and a constituent component derived from a (meth)acrylic monomer and/or Alternatively, it is more preferable to have a component derived from a vinyl monomer other than a styrene compound and a component derived from a styrene compound (styrene component).
The polymer may have other copolymerizable components.

The hydrogen-bonding group (BHa) may be introduced into any component that constitutes the polymer, but it is introduced into a component derived from a (meth)acrylic monomer or a vinyl monomer. It is preferable. When distinguishing a component into which a hydrogen-bonding group (BHa) has been introduced from a component derived from a (meth)acrylic monomer or vinyl monomer into which a hydrogen-bonding group (BHa) has not been introduced, for convenience, hydrogen-bonding It is called a component.
As described above, the hydrogen-bonding component is a component having a main chain of a polymer, a hydrogen-bonding group (BHa), and a group that connects them. When this hydrogen-bonding component is a component derived from a (meth)acrylic monomer, a hydrogen-bonding group (BHa) is linked to the side chain terminal group of the component derived from the (meth)acrylic compound (M). Examples include constituent components introduced as groups or (terminal) substituents. In addition, when the hydrogen-bonding component is a component derived from a vinyl monomer, a hydrogen-bonding group (BHa) is attached to the side chain terminal group of the component derived from the vinyl compound as a linking group or (terminal) substituent. Introduced structural components are mentioned. When a hydrogen-bonding group (BHa) is introduced as a linking group, its terminal group can be the above-mentioned terminal substituent.

Preferred examples of the polymer include vinyl polymers and (meth)acrylic polymers.
The vinyl polymer is not particularly limited, but includes, for example, a polymer containing, for example, 50% by mass or more of a vinyl monomer other than the (meth)acrylic compound (M). Examples of the vinyl monomer include the above-mentioned vinyl compounds. Vinyl polymers include polyvinyl alcohol, polyvinyl acetal, polyvinyl acetate, copolymers containing these, and the like.
The vinyl polymer preferably has a component derived from a vinyl monomer and a hydrogen-bonding component, and further includes a component derived from a (meth)acrylic compound (M) forming a (meth)acrylic polymer described below, It may have a constituent component (MM) derived from a macromonomer.

The content of the constituent components in the vinyl polymer is not particularly limited, and is appropriately selected in consideration of solubility in the dispersion medium, SP value, etc., and for example, within the following range based on 100% by mass of all constituent components Can be set.
The content of the constituent components derived from the vinyl monomer (if the hydrogen-bonding constituents also correspond to this constituent component, the contents of the hydrogen-bonding constituents are summed. The same applies hereinafter) is determined by the dispersion characteristics, and even the resistance. The content of the component derived from the (meth)acrylic compound (M) in the (meth)acrylic polymer is preferably the same as that of the (meth)acrylic compound (M) in terms of cycle characteristics and cycle characteristics. The content of the constituent components derived from styrene compounds among the vinyl monomers in the vinyl polymer is appropriately set in consideration of the content range of the constituent constituents derived from the vinyl monomers, but the resistance and cycle characteristics In this respect, the content is preferably 50 to 90% by weight, more preferably 53 to 80% by weight, and particularly preferably 55 to 75% by weight.
The content of the hydrogen-bonding component in the vinyl polymer is appropriately determined in consideration of the content of the component derived from the vinyl monomer or the (meth)acrylic compound (M) described below. For example, in terms of dispersion properties, furthermore, resistance and cycle properties, in polymers C1-1 and C2, the content is preferably 3 to 40% by mass, more preferably 5 to 35% by mass, and 10 to 30% by mass. Particularly preferred is 30% by mass.
The content of the constituent components derived from the (meth)acrylic compound (M) (if the hydrogen bonding constituent also corresponds to this constituent, the content of the hydrogen bonding constituent is added up; the same applies hereinafter): There is no particular restriction as long as the amount is less than 50% by weight in the polymer, but it is preferably 0 to 47% by weight, more preferably 15 to 45% by weight. Among the (meth)acrylic compounds (M), the content in the vinyl polymer of the constituent components derived from the (meth)acrylic acid ester compounds of aliphatic hydrocarbons having 4 or more carbon atoms is as follows: It is appropriately set in consideration of the content range of the constituent components derived from M). For example, it is preferably 5 to 45% by weight, more preferably 8 to 35% by weight, and particularly preferably 10 to 25% by weight.
The content of the constituent component (MM) is preferably the same as the content in the (meth)acrylic polymer.
When other constituent components are contained, their content is determined as appropriate.

The (meth)acrylic polymer is not particularly limited, but for example, a polymer obtained by (co)polymerizing at least one of the above-mentioned (meth)acrylic compounds (M) is preferable. Also preferred is a (meth)acrylic polymer consisting of a copolymer of a (meth)acrylic compound (M) and another polymerizable compound (N). Other polymerizable compounds (N) are not particularly limited, and include the above-mentioned vinyl compounds and the like. The (meth)acrylic polymer has constituent components derived from the above-mentioned low molecular weight monomers (without polymer chains) and does not have constituent components (MM) derived from macromonomers having polymer chains. It includes embodiments and embodiments having a constituent component (MM). Examples of this macromonomer include, but are not limited to, (meth)acrylic monomers or vinyl monomers having a polymer chain with a number average molecular weight of 1,000 or more. Specifically, the macromonomer described in Patent Document 1 ( X). Examples of the (meth)acrylic polymer include those described in Japanese Patent No. 6295332.

The content of the constituent components in the (meth)acrylic polymer is not particularly limited and is appropriately selected in consideration of solubility in the dispersion medium, SP value, etc. Can be set within the range.
The content of the component derived from the (meth)acrylic compound (M) in the (meth)acrylic polymer is not particularly limited, and can be 100% by mass, but it is important to note the dispersion properties, resistance and cycle properties. In this respect, the amount is preferably 1 to 90% by weight, more preferably 10 to 80% by weight, and particularly preferably 20 to 70% by weight. In addition, the content in the (meth)acrylic polymer of the component derived from the (meth)acrylic acid ester compound of an aliphatic hydrocarbon having 4 or more carbon atoms is derived from the above (meth)acrylic compound (M). It is appropriately set in consideration of the content range of the constituent components. For example, it is preferably 10 to 95% by weight, more preferably 30 to 85%, and particularly preferably 40 to 80% by weight.
The content of the hydrogen-bonding component in the (meth)acrylic polymer is appropriately determined in consideration of the content of the (meth)acrylic compound (M) or the vinyl monomer described below. For example, in terms of dispersion properties, further resistance and cycle properties, in polymers C1-1 and C2, the content is preferably 3 to 40% by mass, more preferably 5 to 35% by mass, and 10% by mass. It is particularly preferred that the amount is 30% by mass.
The content of the component derived from the polymerizable compound (N) in the (meth)acrylic polymer is not particularly limited, but is preferably 1% by mass or more and less than 50% by mass, and 10% by mass or more and less than 50% by mass. %, and particularly preferably 20% by mass or more and less than 50% by mass.
The content of the constituent component (MM) is preferably 0 to 50% by mass, more preferably 0 to 30% by mass.
When containing other constituent components, the content thereof is determined as appropriate.

The polymer may have substituents. The substituent is not particularly limited, and preferably includes a group selected from the following substituents Z.
Since a polymer binder composed of a polymer has the function of binding solid particles as described above, the polymer does not have a substituent (for example, a polar group such as a carboxy group) that exhibits adsorption to solid particles. You can.

- Substituent Z -
Alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, such as methyl, ethyl, isopropyl, t-butyl, pentyl, heptyl, 1-ethylpentyl, benzyl, 2-ethoxyethyl, 1-carboxymethyl, etc.), alkenyl group (preferably an alkenyl group having 2 to 20 carbon atoms, such as vinyl, allyl, oleyl, etc.), an alkynyl group (preferably an alkynyl group having 2 to 20 carbon atoms, such as ethynyl, butadiynyl, phenylethynyl, etc.), cycloalkyl group (Preferably a cycloalkyl group having 3 to 20 carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, etc. In this specification, the term alkyl group usually includes a cycloalkyl group, but here ), an aryl group (preferably an aryl group having 6 to 26 carbon atoms, such as phenyl, 1-naphthyl, 4-methoxyphenyl, 2-chlorophenyl, 3-methylphenyl, etc.), an aralkyl group (preferably a carbon number 7 ~23 aralkyl groups, such as benzyl, phenethyl, etc.), heterocyclic groups (preferably heterocyclic groups having 2 to 20 carbon atoms, more preferably 5 or It is a 6-membered heterocyclic group.Heterocyclic groups include aromatic heterocyclic groups and aliphatic heterocyclic groups.For example, tetrahydropyran ring group, tetrahydrofuran ring group, 2-pyridyl, 4-pyridyl, 2- imidazolyl, 2-benzimidazolyl, 2-thiazolyl, 2-oxazolyl, pyrrolidone group, etc.), alkoxy group (preferably an alkoxy group having 1 to 20 carbon atoms, such as methoxy, ethoxy, isopropyloxy, benzyloxy, etc.), aryloxy group (Preferably an aryloxy group having 6 to 26 carbon atoms, such as phenoxy, 1-naphthyloxy, 3-methylphenoxy, 4-methoxyphenoxy, etc. In this specification, the term aryloxy group refers to an aryloyloxy group) ), a heterocyclic oxy group (a group in which an -O- group is bonded to the above heterocyclic group), an alkoxycarbonyl group (preferably an alkoxycarbonyl group having 2 to 20 carbon atoms, such as ethoxycarbonyl, 2-ethylhexyloxycarbonyl) , dodecyloxycarbonyl, etc.), aryloxycarbonyl group (preferably an aryloxycarbonyl group having 6 to 26 carbon atoms, such as phenoxycarbonyl, 1-naphthyloxycarbonyl, 3-methylphenoxycarbonyl, 4-methoxyphenoxycarbonyl, etc.), A heterocyclic oxycarbonyl group (a group in which an -O-CO- group is bonded to the above heterocyclic group), an amino group (preferably an amino group having 0 to 20 carbon atoms, an alkylamino group, an arylamino group, such as an amino (-NH ₂ ), N,N-dimethylamino, N,N-diethylamino, N-ethylamino, anilino, etc.), sulfamoyl group (preferably a sulfamoyl group having 0 to 20 carbon atoms, such as N,N-dimethylsulf famoyl, N-phenylsulfamoyl, etc.), acyl groups (including alkylcarbonyl groups, alkenylcarbonyl groups, alkynylcarbonyl groups, arylcarbonyl groups, heterocyclic carbonyl groups, preferably acyl groups having 1 to 20 carbon atoms, e.g. , acetyl, propionyl, butyryl, octanoyl, hexadecanoyl, acryloyl, methacryloyl, crotonoyl, benzoyl, naphthoyl, nicotinoyl, etc.), acyloxy group (alkylcarbonyloxy group, alkenylcarbonyloxy group, alkynylcarbonyloxy group, arylcarbonyloxy group, Contains a heterocyclic carbonyloxy group, preferably an acyloxy group having 1 to 20 carbon atoms, such as acetyloxy, propionyloxy, butyryloxy, octanoyloxy, hexadecanoyloxy, acryloyloxy, methacryloyloxy, crotonoyloxy, benzoyloxy , naphthoyloxy, nicotinoyloxy, etc.), an aryloyloxy group (preferably an aryloyloxy group having 7 to 23 carbon atoms, such as benzoyloxy), a carbamoyl group (preferably a carbamoyl group having 1 to 20 carbon atoms, For example, N,N-dimethylcarbamoyl, N-phenylcarbamoyl, etc.), acylamino groups (preferably acylamino groups having 1 to 20 carbon atoms, such as acetylamino, benzoylamino, etc.), alkylthio groups (preferably 1 to 20 carbon atoms), alkylthio groups such as methylthio, ethylthio, isopropylthio, benzylthio, etc.), arylthio groups (preferably arylthio groups having 6 to 26 carbon atoms, such as phenylthio, 1-naphthylthio, 3-methylphenylthio, 4-methoxyphenylthio) etc.), heterocyclic thio group (a group in which -S- group is bonded to the above heterocyclic group), alkylsulfonyl group (preferably an alkylsulfonyl group having 1 to 20 carbon atoms, such as methylsulfonyl, ethylsulfonyl, etc.), aryl A sulfonyl group (preferably an arylsulfonyl group having 6 to 22 carbon atoms, such as benzenesulfonyl), an alkylsilyl group (preferably an alkylsilyl group having 1 to 20 carbon atoms, such as monomethylsilyl, dimethylsilyl, trimethylsilyl, triethylsilyl) ), arylsilyl groups (preferably arylsilyl groups having 6 to 42 carbon atoms, such as triphenylsilyl), alkoxysilyl groups (preferably alkoxysilyl groups having 1 to 20 carbon atoms, such as monomethoxysilyl, dimethoxysilyl), silyl, trimethoxysilyl, triethoxysilyl, etc.), aryloxysilyl group (preferably an aryloxysilyl group having 6 to 42 carbon atoms, such as triphenyloxysilyl), phosphoryl group (preferably having 0 to 20 carbon atoms), Phosphoric acid group, such as -OP(=O)(R ^P ) ₂ ), phosphonyl group (preferably a phosphonyl group having 0 to 20 carbon atoms, such as -P(=O)(R ^P ) ₂ ), phosphinyl group (preferably a phosphinyl group having 0 to 20 carbon atoms, such as -P(R ^P ) ₂ ), a phosphonic acid group (preferably a phosphonic acid group having 0 to 20 carbon atoms, such as -PO(OR ^P ) ₂ ), Examples thereof include a sulfo group (sulfonic acid group), a carboxy group, a hydroxy group, a sulfanyl group, a cyano group, and a halogen atom (eg, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.). R ^P is a hydrogen atom or a substituent (preferably a group selected from substituents Z).
Further, each of the groups listed as the substituent Z may be further substituted by the above substituent Z.
The above-mentioned alkyl group, alkylene group, alkenyl group, alkenylene group, alkynyl group and/or alkynylene group may be cyclic or chain-like, and may be linear or branched.

(Polymer physical properties or characteristics, etc.)
The polymer preferably has the following physical properties or characteristics.
The water concentration of the polymer is preferably 100 ppm (based on mass) or less. Moreover, this polymer may be crystallized and dried, or a polymer solution may be used as it is.
Preferably, the polymer is amorphous. In the present invention, a polymer being "amorphous" typically means that no endothermic peak due to crystal melting is observed when measured at the glass transition temperature.

The polymer may be a non-crosslinked polymer or a crosslinked polymer. Further, when crosslinking of the polymer progresses by heating or application of voltage, the molecular weight may be larger than the above molecular weight. Preferably, the polymer has a mass average molecular weight within the range described below when the all-solid-state secondary battery is started to be used.

The weight average molecular weight of the polymer is not particularly limited. For example, it is preferably 15,000 or more, more preferably 30,000 or more, and even more preferably 50,000 or more. The upper limit is substantially 5,000,000 or less, preferably 4,000,000 or less, more preferably 3,000,000 or less, and even more preferably 1,000,000 or less.

-Measurement of molecular weight-
In the present invention, the molecular weights of polymers, polymer chains, and macromonomers refer to mass average molecular weights or number average molecular weights measured by gel permeation chromatography (GPC) in terms of standard polystyrene, unless otherwise specified. The measurement method basically includes the method under the following condition 1 or condition 2 (priority). However, depending on the type of polymer or macromonomer, an appropriate eluent may be selected and used.
(Condition 1)
Column: Connect two TOSOH TSKgel Super AWM-H (product name, manufactured by Tosoh Corporation) Carrier: 10mMLiBr/N-methylpyrrolidone Measurement temperature: 40°C
Carrier flow rate: 1.0ml/min
Sample concentration: 0.1% by mass
Detector: RI (refractive index) detector (condition 2)
Column: A column in which TOSOH TSKgel Super HZM-H, TOSOH TSKgel Super HZ4000, and TOSOH TSKgel Super HZ2000 (all trade names, manufactured by Tosoh Corporation) are connected is used.
Carrier: Tetrahydrofuran Measurement temperature: 40℃
Carrier flow rate: 1.0ml/min
Sample concentration: 0.1% by mass
Detector: RI (refractive index) detector

A polymer can be synthesized by selecting a raw material compound (monomer) and polymerizing the raw material compound by a known method. The method of incorporating a hydrogen bonding group is not particularly limited, and includes, for example, a method of copolymerizing a compound having a hydrogen bonding group, a method of using a polymerization initiator or a chain transfer agent having (generates) a hydrogen bonding group, Examples include methods that utilize polymer reactions.
Specific examples of the polymer and combinations of components constituting the polymer binder include those shown in Examples, but the present invention is not limited thereto.

The inorganic solid electrolyte-containing composition of the present invention may contain a component constituting one type of polymer binder, or may contain a component constituting multiple types of polymer binders.

The content of the binder components in the inorganic solid electrolyte-containing composition is as described above, but assuming that these components form a polymer binder, the inorganic solid electrolyte-containing composition (constituent layer) of the polymer binder From the viewpoint of dispersion characteristics, resistance reduction, and cycle characteristics, the content is preferably 0.1 to 10.0% by mass, and 0.2 to 5% by mass based on the total mass of the composition (constituent layer). The content is more preferably 0.0% by weight, and even more preferably 0.3 to 4.0% by weight. On the other hand, when the solid content is 100% by mass, for the same reason, it is preferably 0.1 to 10.0% by mass, more preferably 0.3 to 8% by mass, and 0.5 to 7% by mass. % is more preferable.

In the present invention, at a solid content of 100% by mass, the mass ratio of the total content of the inorganic solid electrolyte and the active material to the above content of the polymer binder [(mass of the inorganic solid electrolyte + mass of the active material)/(mass of the polymer binder) Mass)] is preferably in the range of 1,000 to 1. This ratio is more preferably 500-2, and even more preferably 100-10.

<Dispersion medium>
The inorganic solid electrolyte-containing composition of the present invention preferably contains a dispersion medium that dissolves or disperses each of the above components.
The dispersion medium may be any organic compound that is liquid in the environment in which it is used, such as various organic solvents, specifically alcohol compounds, ether compounds, amide compounds, amine compounds, ketone compounds, and aromatic compounds. , aliphatic compounds, nitrile compounds, ester compounds and the like.
The dispersion medium may be either a non-polar dispersion medium (hydrophobic dispersion medium) or a polar dispersion medium (hydrophilic dispersion medium), but non-polar dispersion medium is preferred since it can exhibit excellent dispersion characteristics. A non-polar dispersion medium generally refers to a property that has a low affinity for water, but in the present invention, examples include ester compounds, ketone compounds, ether compounds, aromatic compounds, aliphatic compounds, etc. Among them, ketones Preferable examples include compounds, aliphatic compounds and ester compounds.

Examples of alcohol compounds include methyl alcohol, ethyl alcohol, 1-propyl alcohol, 2-propyl alcohol, 2-butanol, ethylene glycol, propylene glycol, glycerin, 1,6-hexanediol, cyclohexanediol, sorbitol, xylitol, -Methyl-2,4-pentanediol, 1,3-butanediol, and 1,4-butanediol.

Examples of ether compounds include alkylene glycols (diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, etc.), alkylene glycol monoalkyl ethers (ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, propylene glycol monomethyl ether, Dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, diethylene glycol monobutyl ether, etc.), alkylene glycol dialkyl ethers (ethylene glycol dimethyl ether, etc.), dialkyl ethers (dimethyl ether, diethyl ether, diisopropyl ether, dibutyl ether, etc.), cyclic ethers (tetrahydrofuran, dioxane (including 1,2-, 1,3- and 1,4-isomers), etc.).

Examples of the amide compound include N,N-dimethylformamide, N-methyl-2-pyrrolidone, 2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, formamide, N-methylformamide, and acetamide. , N-methylacetamide, N,N-dimethylacetamide, N-methylpropanamide, hexamethylphosphoric triamide, and the like.

Examples of the amine compound include triethylamine, diisopropylethylamine, and tributylamine.
Examples of ketone compounds include acetone, methyl ethyl ketone, methyl isobutyl ketone (MIBK), cyclopentanone, cyclohexanone, cycloheptanone, dipropyl ketone, dibutyl ketone, diisopropyl ketone, diisobutyl ketone (DIBK), isobutylpropyl ketone, sec- Examples include butylpropylketone, pentylpropylketone, butylpropylketone, and the like.
Examples of aromatic compounds include benzene, toluene, xylene, and the like.
Examples of the aliphatic compound include hexane, heptane, octane, nonane, decane, dodecane, cyclohexane, methylcyclohexane, ethylcyclohexane, cycloheptane, cyclooctane, decalin, paraffin, gasoline, naphtha, kerosene, light oil, and the like.
Examples of the nitrile compound include acetonitrile, propionitrile, isobutyronitrile, and the like.
Examples of ester compounds include ethyl acetate, butyl acetate, propyl acetate, propyl butyrate, isopropyl butyrate, butyl butyrate, isobutyl butyrate, butyl pentanoate, ethyl isobutyrate, propyl isobutyrate, isopropyl isobutyrate, isobutyl isobutyrate, and pivalic acid. Propyl, isopropyl pivalate, butyl pivalate, isobutyl pivalate, and the like.

In the present invention, ether compounds, ketone compounds, aromatic compounds, aliphatic compounds, and ester compounds are preferred, and ester compounds, ketone compounds, and ether compounds are more preferred.

The number of carbon atoms in the compound constituting the dispersion medium is not particularly limited, and is preferably from 2 to 30, more preferably from 4 to 20, even more preferably from 6 to 15, and particularly preferably from 7 to 12.

In terms of dispersion characteristics, the dispersion medium preferably has an SP value (unit: MPa ^1/2 ) of 15 to 21, more preferably 16 to 20, and even more preferably 17 to 19. The difference (absolute value) in SP value between the polymer C1-1 or C2 and the dispersion medium is not particularly limited, but it is preferably 3 or less, and 0 to 2. It is more preferably 5, and even more preferably 0 to 2.0. When containing multiple polymers, it is preferable that the smallest difference (absolute value) in SP values is within the above range, and all differences (absolute values) are within the above range. Good too.
The SP value of the dispersion medium is a value obtained by converting the SP value calculated by the Hoy method described above into a unit of MPa ^1/2 . When the inorganic solid electrolyte-containing composition contains two or more types of dispersion medium, the SP value of the dispersion medium means the SP value of the entire dispersion medium, and is the product of the SP value of each dispersion medium and the mass fraction. Let it be the sum. Specifically, it is calculated in the same manner as the method for calculating the SP value of the polymer described above, except that the SP value of each dispersion medium is used instead of the SP value of the constituent components.
The SP value (units are omitted) of the dispersion medium is shown below.
MIBK (18.4), diisopropyl ether (16.8), dibutyl ether (17.9), diisopropyl ketone (17.9), DIBK (17.9), butyl butyrate (18.6), butyl acetate (18) .9), toluene (18.5), ethylcyclohexane (17.1), cyclooctane (18.8), isobutyl ethyl ether (15.3), N-methylpyrrolidone (NMP, SP value: 25.4)

The boiling point of the dispersion medium at normal pressure (1 atm) is preferably 50°C or higher, more preferably 70°C or higher. The upper limit is preferably 250°C or less, more preferably 220°C or less.

The inorganic solid electrolyte-containing composition of the present invention only needs to contain at least one type of dispersion medium, and may contain two or more types.
In the present invention, the content of the dispersion medium in the inorganic solid electrolyte-containing composition is not particularly limited and can be set as appropriate. For example, in the inorganic solid electrolyte-containing composition, it is preferably 20 to 80% by mass, more preferably 30 to 70% by mass, and particularly preferably 40 to 60% by mass.

<Active material>
The inorganic solid electrolyte-containing composition of the present invention can also contain an active material capable of inserting and releasing metal ions belonging to Group 1 or Group 2 of the periodic table. Examples of the active material include a positive electrode active material and a negative electrode active material, which will be explained below.
In the present invention, an inorganic solid electrolyte-containing composition containing an active material (positive electrode active material or negative electrode active material) may be referred to as an electrode composition (positive electrode composition or negative electrode composition).

(Cathode active material)
The positive electrode active material is an active material capable of inserting and extracting metal ions belonging to Group 1 or Group 2 of the periodic table, and is preferably one that can reversibly insert and release lithium ions. The material is not particularly limited as long as it has the above characteristics, and may be a transition metal oxide, an organic substance, an element such as sulfur, etc. that can be composited with Li by decomposing the battery.
Among these, it is preferable to use a transition metal oxide as the positive electrode active material, and a transition metal oxide containing a transition metal element M ^a (one or more elements selected from Co, Ni, Fe, Mn, Cu, and V) is preferable. more preferable. In addition, this transition metal oxide contains elements M ^b (elements of group 1 (Ia) of the periodic table of metals other than lithium, elements of group 2 (IIa) of the periodic table of metals, Al, Ga, In, Ge, Sn, Pb, Elements such as Sb, Bi, Si, P, and B may be mixed. The mixing amount is preferably 0 to 30 mol % based on the amount of transition metal element M ^a (100 mol %). More preferably, it is synthesized by mixing Li/M ^a in a molar ratio of 0.3 to 2.2.
Specific examples of transition metal oxides include (MA) transition metal oxides having a layered rock salt structure, (MB) transition metal oxides having a spinel structure, (MC) lithium-containing transition metal phosphate compounds, (MD ) Lithium-containing transition metal halide phosphoric acid compounds and (ME) lithium-containing transition metal silicate compounds.

(MA) Specific examples of transition metal oxides having a layered rock salt type 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 aluminate [NCA]), LiNi _1/3 Co _1/3 Mn _1/3 O ₂ (nickel manganese cobalt lithium [NMC]), and LiNi _0.5 Mn _0.5 O ₂ ( lithium manganese nickelate).
(MB) Specific examples of transition metal oxides having a spinel structure include LiMn ₂ O ₄ (LMO), LiCoMnO ₄ , Li ₂ FeMn ₃ O ₈ , Li ₂ CuMn ₃ O ₈ , Li ₂ CrMn ₃ O ₈ and Li _{2NiMn3O8 is mentioned} .
(MC) Examples of lithium-containing transition metal phosphate compounds include olivine-type iron phosphates such as LiFePO ₄ and Li ₃ Fe ₂ (PO ₄ ) ₃ , iron pyrophosphates such as LiFeP ₂ O ₇ , LiCoPO ₄ , etc. cobalt phosphates and monoclinic nasicon type vanadium phosphate salts such as Li ₃ V ₂ (PO ₄ ) ₃ (lithium vanadium phosphate).
(MD) Examples of lithium-containing transition metal halide phosphate compounds include iron fluorophosphates such as Li ₂ FePO ₄ F, manganese fluorophosphates such as Li ₂ MnPO ₄ F, and Li ₂ CoPO ₄ F. Examples include cobalt fluoride phosphates such as.
(ME) Examples of the lithium-containing transition metal silicate compound include Li ₂ FeSiO ₄ , Li ₂ MnSiO ₄ , Li ₂ CoSiO ₄ , and the like.
In the present invention, (MA) transition metal oxides having a layered rock salt type structure are preferred, and LCO or NMC is more preferred.

The shape of the positive electrode active material is not particularly limited, but a particulate shape is preferable. The average particle diameter (volume average particle diameter) of the positive electrode active material is not particularly limited. For example, it can be 0.1 to 50 μm. The average particle diameter of the positive electrode active material particles can be measured in the same manner as the average particle diameter of the inorganic solid electrolyte. A normal pulverizer or classifier is used to make the positive electrode active material into a predetermined particle size. For example, a mortar, a ball mill, a sand mill, a vibrating ball mill, a satellite ball mill, a planetary ball mill, a swirling air jet mill, a sieve, etc. are preferably used. Wet pulverization can also be carried out in the presence of a dispersion medium such as water or methanol during pulverization. In order to obtain a desired particle size, it is preferable to perform classification. Classification is not particularly limited, and can be performed using a sieve, a wind classifier, or the like. Both dry and wet classification can be used.
The positive electrode active material obtained by the calcination method may be used after being washed with water, an acidic aqueous solution, an alkaline aqueous solution, or an organic solvent.

The positive electrode active materials may be used alone or in combination of two or more.
When forming a positive electrode active material layer, the mass (mg) (basis weight) of the positive electrode active material per unit area (cm ² ) of the positive electrode active material layer is not particularly limited. It can be determined as appropriate depending on the designed battery capacity, and can be, for example, 1 to 100 mg/cm ² .

The content of the positive electrode active material in the inorganic solid electrolyte-containing composition is not particularly limited, and is preferably 10 to 97% by mass, more preferably 30 to 95% by mass, and 40 to 93% by mass based on 100% by mass of solid content. is more preferable, and 50 to 90% by mass is particularly preferable.

(Negative electrode active material)
The negative electrode active material is an active material capable of inserting and extracting ions of metals belonging to Group 1 or Group 2 of the periodic table, and is preferably one that can reversibly insert and release lithium ions. The material is not particularly limited as long as it has the above characteristics, such as carbonaceous materials, metal oxides, metal composite oxides, lithium alone, lithium alloys, and negative electrode active materials that can be alloyed with lithium. Examples include substances. Among these, carbonaceous materials, metal composite oxides, or lithium alone are preferably used from the viewpoint of reliability. An active material that can be alloyed with lithium is preferable in terms of increasing the capacity of an all-solid-state secondary battery. Since the constituent layer formed from the inorganic solid electrolyte-containing composition of the present invention can maintain a strong binding state between solid particles, a negative electrode active material capable of forming an alloy with lithium can be used as the negative electrode active material. This makes it possible to increase the capacity of the all-solid-state secondary battery and extend the life of the battery.

The carbonaceous material used as the negative electrode active material is a material consisting essentially of carbon. For example, petroleum pitch, carbon black such as acetylene black (AB), graphite (natural graphite, artificial graphite such as vapor-grown graphite, etc.), and various synthetic materials such as PAN (polyacrylonitrile) resin or furfuryl alcohol resin. Examples include carbonaceous materials obtained by firing resin. Furthermore, various carbon fibers such as PAN carbon fiber, cellulose carbon fiber, pitch carbon fiber, vapor grown carbon fiber, dehydrated PVA (polyvinyl alcohol) carbon fiber, lignin carbon fiber, glassy carbon fiber, and activated carbon fiber. Mention may also be made of mesophase microspheres, graphite whiskers, and tabular graphite.
These carbonaceous materials can also be divided into non-graphitizable carbonaceous materials (also referred to as hard carbon) and graphite-based carbonaceous materials depending on the degree of graphitization. Further, the carbonaceous material preferably has the interplanar spacing or density and crystallite size described in JP-A-62-22066, JP-A-2-6856, and JP-A-3-45473. The carbonaceous material does not need to be a single material, and a mixture of natural graphite and artificial graphite described in JP-A-5-90844, graphite with a coating layer as described in JP-A-6-4516, etc. may be used. You can also do it.
As the carbonaceous material, hard carbon or graphite is preferably used, and graphite is more preferably used.

The oxide of a metal or metalloid element used as a negative electrode active material is not particularly limited as long as it is an oxide that can absorb and release lithium, and metal element oxides (metal oxides) and composites of metal elements can be used. Examples include oxides or composite oxides of metal elements and metalloid elements (collectively referred to as metal composite oxides), and oxides of metalloid elements (metalloid oxides). As these oxides, amorphous oxides are preferred, and chalcogenides, which are reaction products of metal elements and elements of group 16 of the periodic table, are also preferred. In the present invention, a metalloid element refers to an element that exhibits intermediate properties between a metal element and a non-metallic element, and usually includes six elements: boron, silicon, germanium, arsenic, antimony, and tellurium, and further includes selenium. , polonium and astatine. In addition, amorphous means that it has a broad scattering band with an apex in the 2θ value range of 20° to 40° when measured by X-ray diffraction using CuKα rays, and crystalline diffraction lines are not observed. May have. The strongest intensity of the crystalline diffraction lines observed at 2θ values of 40° to 70° is 100 times or less than the diffraction line intensity at the top of the broad scattering band observed at 2θ values of 20° to 40°. , more preferably 5 times or less, and particularly preferably no crystalline diffraction lines.

Among the compound group consisting of the above-mentioned amorphous oxides and chalcogenides, amorphous oxides of metalloid elements or the above-mentioned chalcogenides are more preferable, and elements of groups 13 (IIIB) to 15 (VB) of the periodic table (e.g. , Al, Ga, Si, Sn, Ge, Pb, Sb and Bi) or a (composite) oxide or chalcogenide consisting of one selected from the group consisting of one or a combination of two or more thereof is particularly preferred. Specific examples of preferable amorphous oxides and chalcogenides include, for example, Ga ₂ O ₃ , GeO, PbO, PbO ₂ , Pb ₂ O ₃ , Pb ₂ O ₄ , Pb ₃ O ₄ , Sb ₂ O ₃ , Sb _{2 O4 , Sb2O8Bi2O3 , Sb2O8Si2O3 , Sb2O5 , Bi2O3 , Bi2O4 , GeS} , _{PbS , PbS2 , Sb2S3} or _{Sb2 S5} is preferred.
Examples of negative electrode active materials that can be used in conjunction with amorphous oxides mainly containing Sn, Si, and Ge include carbonaceous materials that can absorb and/or desorb lithium ions or lithium metal, lithium alone, lithium alloys, and lithium. Preferred examples include negative electrode active materials that can be alloyed with.

The oxide of a metal or metalloid element, particularly the metal (composite) oxide and the chalcogenide described above, preferably contain at least one of titanium and lithium as a constituent from the viewpoint of high current density charge/discharge characteristics. The metal composite oxide containing lithium (lithium composite metal oxide) is, for example, a composite oxide of lithium oxide and the above metal (composite) oxide or the above chalcogenide, more specifically, Li ₂ SnO ₂ Can be mentioned.
Preferably, the negative electrode active material, such as a metal oxide, contains a titanium element (titanium oxide). Specifically, Li ₄ Ti ₅ O ₁₂ (lithium titanate [LTO]) has excellent rapid charging and discharging characteristics due to its small volume fluctuation when intercalating and releasing lithium ions, suppresses electrode deterioration, and is used as a lithium ion secondary material. This is preferable in that the battery life can be improved.

The lithium alloy as the negative electrode active material is not particularly limited as long as it is an alloy that is normally used as a negative electrode active material of secondary batteries. For example, a lithium aluminum alloy containing lithium as a base metal and 10% by mass of aluminum added may be mentioned. It will be done.

The negative electrode active material capable of forming an alloy with lithium is not particularly limited as long as it is commonly used as a negative electrode active material of secondary batteries. Such an active material greatly expands and contracts during charging and discharging of an all-solid-state secondary battery, accelerating the deterioration of cycle characteristics. However, since the inorganic solid electrolyte-containing composition of the present invention contains the above-mentioned binder component, Decrease in cycle characteristics can be suppressed. Examples of such active materials include (negative electrode) active materials (alloys, etc.) containing silicon element or tin element, and metals such as Al and In, and negative electrode active materials containing silicon element that enable higher battery capacity. (Silicon element-containing active material) is preferable, and a silicon element-containing active material in which the content of silicon element is 50 mol% or more of all constituent elements is more preferable.
In general, negative electrodes containing these negative electrode active materials (for example, Si negative electrodes containing silicon element-containing active materials, Sn negative electrodes containing tin active materials, etc.) are carbon negative electrodes (such as graphite and acetylene black). ) can store more Li ions. That is, the amount of Li ions stored per unit mass increases. Therefore, battery capacity (energy density) can be increased. As a result, there is an advantage that the battery operating time can be extended.
Examples of silicon-containing active materials include silicon materials such as Si and SiOx (0<x≦1), and silicon-containing alloys containing titanium, vanadium, chromium, manganese, nickel, copper, lanthanum, etc. (for example, LaSi ₂ , VSi ₂ , La-Si, Gd-Si, Ni-Si) or structured active materials (e.g. LaSi ₂ /Si), as well as silicon elements and tin elements such as SnSiO ₃ and SnSiS ₃ Examples include active materials containing. Note that SiOx itself can be used as a negative electrode active material (semi-metal oxide), and since SiOx generates Si when operating an all-solid-state secondary battery, it can be used as a negative electrode active material that can be alloyed with lithium (semi-metallic oxide). (precursor substances).
Examples of the negative electrode active material containing the tin element include Sn, SnO, SnO ₂ , SnS, SnS ₂ , and active materials containing the silicon element and tin element described above. Further, a composite oxide with lithium oxide, for example, Li ₂ SnO ₂ can also be used.

In the present invention, the above-mentioned negative electrode active materials can be used without particular limitation, but from the viewpoint of battery capacity, negative electrode active materials that can be alloyed with lithium are preferred as negative electrode active materials, and among them, negative electrode active materials that can be alloyed with lithium are preferred. , the silicon material or silicon-containing alloy (alloy containing silicon element) is more preferable, and it is even more preferable to include silicon (Si) or a silicon-containing alloy.

The chemical formula of the compound obtained by the above calcination method can be calculated by inductively coupled plasma (ICP) emission spectrometry as a measurement method, or from the difference in mass of the powder before and after calcination as a simple method.

The shape of the negative electrode active material is not particularly limited, but a particulate shape is preferable. The average particle size (volume average particle size) of the negative electrode active material is not particularly limited, but is preferably 0.1 to 60 μm. The average particle diameter of the negative electrode active material particles can be measured in the same manner as the average particle diameter of the inorganic solid electrolyte. In order to obtain a predetermined particle size, a normal pulverizer or classifier is used as in the case of the positive electrode active material.

The above negative electrode active materials may be used alone or in combination of two or more.
When forming a negative electrode active material layer, the mass (mg) (basis weight) of the negative electrode active material per unit area (cm ² ) of the negative electrode active material layer is not particularly limited. It can be determined as appropriate depending on the designed battery capacity, and can be, for example, 1 to 100 mg/cm ² .

The content of the negative electrode active material in the inorganic solid electrolyte-containing composition is not particularly limited, and is preferably 10 to 90% by mass, more preferably 20 to 85% by mass, and more preferably 30 to 85% by mass based on 100% by mass of solid content. It is more preferably 80% by mass, and even more preferably 40 to 75% by mass.

In the present invention, when the negative electrode active material layer is formed by charging the secondary battery, a metal belonging to Group 1 or Group 2 of the periodic table, which is generated in the all-solid-state secondary battery, is used instead of the negative electrode active material. Ions can be used. A negative electrode active material layer can be formed by combining these ions with electrons and depositing them as metal.

(Active material coating)
The surfaces of the positive electrode active material and the negative electrode active material may be coated with another metal oxide. Examples of the surface coating agent include metal oxides containing Ti, Nb, Ta, W, Zr, Al, Si, or Li. Specific examples include spinel titanate, tantalum oxides, niobium oxides, lithium niobate compounds, and specific examples include Li ₄ Ti ₅ O ₁₂ , Li ₂ Ti ₂ O ₅ , LiTaO ₃ , LiNbO ₃ , LiAlO ₂ , Li ₂ ZrO ₃ , Li ₂ WO ₄ , Li ₂ TiO ₃ , Li ₂ B ₄ O ₇ , Li ₃ PO ₄ , Li ₂ MoO ₄ , Li ₃ BO ₃ , LiBO ₂ , Li ₂ CO ₃ , Li ₂ SiO ₃ , SiO ₂ , TiO ₂ , ZrO ₂ , Al ₂ O ₃ , B ₂ O ₃ and the like.
Further, the electrode surface containing the positive electrode active material or the negative electrode active material may be surface-treated with sulfur or phosphorus.
Furthermore, the particle surface of the positive electrode active material or the negative electrode active material may be surface-treated with active light or active gas (plasma, etc.) before or after the surface coating.

<Conductivity aid>
The inorganic solid electrolyte-containing composition of the present invention preferably contains a conductive aid. For example, it is preferable that a silicon atom-containing active material as a negative electrode active material is used in combination with the conductive aid.
There are no particular limitations on the conductive aid, and those known as general conductive aids can be used. For example, electron conductive materials such as graphites such as natural graphite and artificial graphite, carbon blacks such as acetylene black, Ketjen black, and furnace black, amorphous carbon such as needle coke, vapor-grown carbon fibers, or carbon nanotubes. may be carbon fibers such as carbon fibers such as graphene or fullerene, metal powders such as copper and nickel, metal fibers, and conductive polymers such as polyaniline, polypyrrole, polythiophene, polyacetylene, and polyphenylene derivatives. may also be used.
In the present invention, when an active material and a conductive additive are used together, among the conductive additives mentioned above, metal ions belonging to Group 1 or Group 2 of the periodic table (preferably Li) A conductive additive is one that does not insert or release ions (ions) and does not function as an active material. Therefore, among conductive aids, those that can function as active materials in the active material layer when the battery is charged and discharged are classified as active materials rather than conductive aids. Whether or not it functions as an active material when charging and discharging a battery is not unique, but is determined by the combination with the active material.

The conductive aid may contain one kind or two or more kinds.
The shape of the conductive aid is not particularly limited, but is preferably particulate.
When the inorganic solid electrolyte-containing composition of the present invention contains a conductive aid, the content of the conductive aid in the inorganic solid electrolyte-containing composition is preferably 0 to 10% by mass based on 100% by mass of solid content.

<Lithium salt>
It is also preferable that the inorganic solid electrolyte-containing composition of the present invention contains a lithium salt (supporting electrolyte).
The lithium salt is preferably a lithium salt that is normally used in this type of product, and is not particularly limited. For example, lithium salts described in paragraphs 0082 to 0085 of JP 2015-088486 A are preferred.
When the inorganic solid electrolyte-containing composition of the present invention contains a lithium salt, the content of the lithium salt is preferably 0.1 parts by mass or more, more preferably 5 parts by mass or more, based on 100 parts by mass of the solid electrolyte. The upper limit is preferably 50 parts by mass or less, more preferably 20 parts by mass or less.

<Dispersant>
The inorganic solid electrolyte-containing composition of the present invention does not need to contain any dispersant other than the binder component, since the binder component described above also functions as a dispersant. When the inorganic solid electrolyte-containing composition contains a dispersant other than the binder component, dispersants that are commonly used in all-solid-state secondary batteries can be appropriately selected and used. Generally, compounds intended for particle adsorption and steric repulsion and/or electrostatic repulsion are preferably used.

<Other additives>
In the inorganic solid electrolyte-containing composition of the present invention, other components other than the above-mentioned components include an ionic liquid, a thickener, and a crosslinking agent (such as one that undergoes a crosslinking reaction by radical polymerization, condensation polymerization, or ring-opening polymerization, etc.). , a polymerization initiator (such as one that generates acid or radicals by heat or light), an antifoaming agent, a leveling agent, a dehydrating agent, an antioxidant, and the like. The ionic liquid is contained in order to further improve the ionic conductivity, and any known ionic liquid can be used without particular limitation. Further, the polymer may contain a polymer other than the polymer forming the polymer binder described above, a commonly used binder, and the like.

(Preparation of inorganic solid electrolyte-containing composition)
The inorganic solid electrolyte-containing composition of the present invention includes an inorganic solid electrolyte, a binder component, preferably a dispersion medium, a conductive aid, and, as appropriate, a lithium salt, and any other components, such as a commonly used mixture. It can be prepared as a mixture, preferably as a slurry, by mixing in a machine. In the case of an electrode composition, an active material is further mixed.
The mixing method is not particularly limited, and may be mixed all at once or sequentially. The mixing environment is not particularly limited, but examples include dry air or inert gas. The mixing conditions are not particularly limited, but are preferably conditions that allow the binder components to easily form intermolecular hydrogen bonds, and the type of hydrogen bonding group (BHa) or (BHb), the content of each component, and the polymer C2 It is set appropriately according to the SP value and the like.

[All-solid-state secondary battery sheet]
The all-solid-state secondary battery sheet of the present invention is a sheet-like molded product that can form a constituent layer of an all-solid-state secondary battery, and includes various embodiments depending on its use. For example, a sheet preferably used for a solid electrolyte layer (also referred to as a solid electrolyte sheet for an all-solid-state secondary battery), a sheet preferably used for an electrode, or a laminate of an electrode and a solid electrolyte layer (an electrode for an all-solid-state secondary battery). sheets), etc. In the present invention, these various sheets are collectively referred to as sheets for all-solid-state secondary batteries.

The solid electrolyte sheet for an all-solid-state secondary battery of the present invention may be any sheet that has a solid electrolyte layer, and may be a sheet in which the solid electrolyte layer is formed on a base material or a sheet that does not have a base material and has a solid electrolyte layer. It may also be a sheet formed from. The solid electrolyte sheet for an all-solid-state secondary battery may have other layers in addition to the solid electrolyte layer. Examples of other layers include a protective layer (release sheet), a current collector, and a coat layer.
As the solid electrolyte sheet for an all-solid-state secondary battery of the present invention, for example, a sheet having a layer composed of the inorganic solid electrolyte-containing composition of the present invention, usually a solid electrolyte layer, and a protective layer in this order on a base material. can be mentioned. The layer thickness of each layer constituting the solid electrolyte sheet for an all-solid-state secondary battery is the same as the layer thickness of each layer explained in the all-solid-state secondary battery described below.

The solid electrolyte layer included in the solid electrolyte sheet for an all-solid-state secondary battery is preferably formed of the inorganic solid electrolyte-containing composition of the present invention.
It is believed that in the film forming process of the inorganic solid electrolyte-containing composition of the present invention, intermolecular hydrogen bonds formed by the polymer C1-1 or C2 are broken and intramolecular hydrogen bonds are formed. As the formation of intramolecular hydrogen bonds progresses, the solubility of the polymer C1-1 or C2 in the dispersion medium gradually decreases, and the polymer C1-1 or C2 solidifies or precipitates, preferably in the form of particles, while maintaining the adsorption state with the solid particles. Therefore, while maintaining strong binding between solid particles, it is possible to sufficiently construct an ion conduction path without covering the entire surface of the solid particles. The solid electrolyte layer made of this inorganic solid electrolyte-containing composition preferably contains particles of a polymer binder formed by hydrogen bonding of binder components.
As mentioned above, the constituent layer formed of the inorganic solid electrolyte-containing composition of the present invention contains a polymer binder in which polymer C1-1 or C2 has intramolecular hydrogen bonds, but the inorganic solid electrolyte-containing composition It is not necessary that all of the polymers C1-1 or C2 contained therein form a polymer binder, and as long as the effects of the present invention are not impaired, polymers C1-1 or C2 that do not have intramolecular hydrogen bonds may be used. It may be contained (residual).
The content of each component in the constituent layer is not particularly limited, but preferably has the same meaning as the content of each component in the solid content of the inorganic solid electrolyte-containing composition of the present invention. However, the content of polymer binder usually corresponds to the total content of the binder components.

The base material is not particularly limited as long as it can support the solid electrolyte layer, and examples thereof include sheets (plate-like bodies) of materials such as materials described below for the current collector, organic materials, and inorganic materials. Examples of the organic material include various polymers, and specific examples include polyethylene terephthalate, polypropylene, polyethylene, cellulose, and the like. Examples of inorganic materials include glass and ceramics.

The electrode sheet for all-solid-state secondary batteries (also simply referred to as "electrode sheet") of the present invention may be any electrode sheet having an active material layer, and the active material layer may be formed on a base material (current collector). The active material layer may be a sheet having no base material, or a sheet formed from an active material layer without a base material. This electrode sheet is usually a sheet having a current collector and an active material layer, but there are also embodiments in which the current collector, an active material layer, and a solid electrolyte layer are included in this order, and a current collector, an active material layer, and a solid electrolyte layer. Also included are embodiments having layers and active material layers in this order.
At least one of the solid electrolyte layer and the active material layer of the electrode sheet is formed from the inorganic solid electrolyte-containing composition of the present invention. In the solid electrolyte layer and active material layer formed of the inorganic solid electrolyte-containing composition of the present invention, the state of presence of the polymer binder (state of hydrogen bond formation) is the solid electrolyte layer of the solid electrolyte sheet for all-solid-state secondary batteries described above. The state of existence is the same as in . Further, the content of each component in the solid electrolyte layer or the active material layer is not particularly limited, but preferably the content of each component in the solid content of the inorganic solid electrolyte-containing composition (electrode composition) of the present invention. is synonymous with However, the content of polymer binder usually corresponds to the total content of the binder components. The layer thickness of each layer constituting the electrode sheet of the present invention is the same as the layer thickness of each layer explained in the all-solid-state secondary battery described below. The electrode sheet of the present invention may have other layers described above.
Note that when the solid electrolyte layer or the active material layer is not formed from the inorganic solid electrolyte-containing composition of the present invention, it is formed from a normal constituent layer forming material.

In the all-solid-state secondary battery sheet of the present invention, at least one of the solid electrolyte layer and the active material layer is formed of the inorganic solid electrolyte-containing composition of the present invention, while suppressing an increase in interfacial resistance between solid particles. It has a constituent layer with a flat surface in which solid particles are firmly bound together. This constituent layer preferably exhibits smoothness such that the maximum deviation value is less than 8% in the surface smoothness test in Examples described below. Therefore, by using the all-solid-state secondary battery sheet of the present invention as a constituent layer of an all-solid-state secondary battery, it is possible to achieve low resistance (high conductivity) and excellent cycle characteristics of the all-solid-state secondary battery. In particular, an electrode sheet for an all-solid-state secondary battery and an all-solid-state secondary battery in which the active material layer is formed from the inorganic solid electrolyte-containing composition of the present invention exhibit strong adhesion between the active material layer and the current collector, and Further improvements in characteristics can be achieved. Therefore, the all-solid-state secondary battery sheet of the present invention is suitably used as a sheet that can form constituent layers of an all-solid-state secondary battery.
In the present invention, each layer constituting the all-solid-state secondary battery sheet may have a single-layer structure or a multi-layer structure.

[Method for manufacturing sheet for all-solid-state secondary battery]
The method for producing the all-solid-state secondary battery sheet of the present invention is not particularly limited, and the sheet can be produced by forming each of the above layers using the inorganic solid electrolyte-containing composition of the present invention. For example, preferably, a layer (coated dry layer) made of the inorganic solid electrolyte-containing composition is formed by forming a film (coating and drying) on a base material or a current collector (possibly with another layer interposed therebetween). There are several methods. Thereby, an all-solid-state secondary battery sheet having a base material or a current collector and a coating drying layer can be produced. In particular, when an all-solid-state secondary battery sheet is produced by forming a film of the inorganic solid electrolyte-containing composition of the present invention on a current collector, the adhesion between the current collector and the active material layer can be strengthened. Here, the applied dry layer is a layer formed by applying the inorganic solid electrolyte-containing composition of the present invention and drying the dispersion medium (i.e., a layer formed using the inorganic solid electrolyte-containing composition of the present invention, A layer formed by removing the dispersion medium from the inorganic solid electrolyte-containing composition of the present invention. The dispersion medium may remain in the active material layer and the coating drying layer as long as it does not impair the effects of the present invention, and the remaining amount can be, for example, 3% by mass or less in each layer. As described above, this coated dry layer contains a polymer binder formed by hydrogen bonding of polymer C1-1 or C2.
In the method for manufacturing an all-solid-state secondary battery sheet of the present invention, each process such as coating and drying will be explained in the following method for manufacturing an all-solid-state secondary battery.
In the above preferred method, when an all-solid-state secondary battery sheet is produced by forming a film of the inorganic solid electrolyte-containing composition of the present invention on a current collector, the adhesion between the current collector and the active material layer can be strengthened. .

In the method for producing an all-solid-state secondary battery sheet of the present invention, the coated dry layer obtained as described above can also be pressurized. Pressurization conditions and the like will be explained in the method for manufacturing an all-solid-state secondary battery, which will be described later.
In addition, in the method for manufacturing a sheet for an all-solid-state secondary battery of the present invention, the base material, the protective layer (particularly the release sheet), etc. can also be peeled off.

[All-solid-state secondary battery]
The all-solid-state secondary battery of the present invention includes a positive electrode active material layer, a negative electrode active material layer facing the positive electrode active material layer, and a solid electrolyte layer disposed between the positive electrode active material layer and the negative electrode active material layer. have The positive electrode active material layer is preferably formed on the positive electrode current collector and constitutes a positive electrode. The negative electrode active material layer is preferably formed on the negative electrode current collector and constitutes a negative electrode.
At least one of the negative electrode active material layer, the positive electrode active material layer, and the solid electrolyte layer is formed of the inorganic solid electrolyte-containing composition of the present invention, and at least one of the solid electrolyte layer, the negative electrode active material layer, and the positive electrode active material layer Preferably, one of the two is formed of the inorganic solid electrolyte-containing composition of the present invention. It is also one of the preferred embodiments that all the layers are formed from the inorganic solid electrolyte-containing composition of the present invention. In the present invention, forming the constituent layers of an all-solid-state secondary battery with the inorganic solid electrolyte-containing composition of the present invention refers to the all-solid-state secondary battery sheet of the present invention (however, forming the constituent layers of an all-solid-state secondary battery with the inorganic solid electrolyte-containing composition of the present invention) In the case where the sheet has a layer other than the formed layer, it includes an embodiment in which the constituent layer is formed using a sheet from which this layer is removed. The active material layer or solid electrolyte layer formed from the inorganic solid electrolyte-containing composition of the present invention preferably has different types of components and their contents in accordance with the solid content of the inorganic solid electrolyte-containing composition of the present invention. the same (although the content of polymeric binder usually corresponds to the total content of the binder components). Note that when the active material layer or the solid electrolyte layer is not formed from the inorganic solid electrolyte-containing composition of the present invention, known materials can be used.
The thicknesses of the negative electrode active material layer, solid electrolyte layer, and positive electrode active material layer are not particularly limited. Considering the dimensions of a typical all-solid-state secondary battery, the thickness of each layer is preferably 10 to 1,000 μm, more preferably 20 μm or more and less than 500 μm. In the all-solid-state secondary battery of the present invention, the thickness of at least one of the positive electrode active material layer and the negative electrode active material layer is more preferably 50 μm or more and less than 500 μm.
The positive electrode active material layer and the negative electrode active material layer may each include a current collector on the side opposite to the solid electrolyte layer.

<Housing>
Depending on the application, the all-solid-state secondary battery of the present invention may be used as an all-solid-state secondary battery with the above structure, but in order to form a dry battery, it may be further enclosed in a suitable housing. is preferred. The housing may be made of metal or resin (plastic). When using a metal material, for example, one made of aluminum alloy or stainless steel can be used. It is preferable that the metal casing is divided into a casing on the positive electrode side and a casing on the negative electrode side, and electrically connected to the positive electrode current collector and the negative electrode current collector, respectively. It is preferable that the positive electrode side casing and the negative electrode side casing be joined and integrated via a short-circuit prevention gasket.

An all-solid-state secondary battery according to a preferred embodiment of the present invention will be described below with reference to FIG. 1, but the present invention is not limited thereto.

FIG. 1 is a cross-sectional view schematically showing an all-solid-state secondary battery (lithium ion secondary battery) according to a preferred embodiment of the present invention. The all-solid-state secondary battery 10 of the present embodiment includes, in this order, a negative electrode current collector 1, a negative electrode active material layer 2, a solid electrolyte layer 3, a positive electrode active material layer 4, and a positive electrode current collector 5 when viewed from the negative electrode side. . The layers are in contact with each other and have an adjacent structure. By adopting such a structure, during charging, electrons (e ⁻ ) are supplied to the negative electrode side, and lithium ions (Li ⁺ ) are accumulated there. On the other hand, during discharging, lithium ions (Li ⁺ ) accumulated in the negative electrode are returned to the positive electrode side, and electrons are supplied to the operating region 6 . In the illustrated example, a light bulb is used as a model for the operating portion 6, and the light bulb is lit by discharge.

When an all-solid-state secondary battery having the layer structure shown in FIG. 12 in a 2032-type coin case 11 (for example, a coin-shaped all-solid-state secondary battery shown in FIG. 2) is sometimes called an all-solid-state secondary battery 13.

(positive electrode active material layer, solid electrolyte layer, negative electrode active material layer)
In the all-solid-state secondary battery 10, all of the positive electrode active material layer, solid electrolyte layer, and negative electrode active material layer are formed from the inorganic solid electrolyte-containing composition of the present invention. The state of existence of the polymer binder (formation state of hydrogen bonds) in the positive electrode active material layer 4, solid electrolyte layer 3, and negative electrode active material layer 2 is the state of existence in the solid electrolyte layer of the solid electrolyte sheet for all-solid-state secondary batteries described above. is the same as This all-solid-state secondary battery 10 exhibits excellent battery performance. The inorganic solid electrolyte and polymer binder contained in the positive electrode active material layer 4, solid electrolyte layer 3, and negative electrode active material layer 2 may be the same or different.
In the present invention, either or both of the positive electrode active material layer and the negative electrode active material layer may be simply referred to as an active material layer or an electrode active material layer. Further, either or both of the positive electrode active material and the negative electrode active material may be simply referred to as an active material or an electrode active material.

In the present invention, when the constituent layers are formed from the inorganic solid electrolyte-containing composition of the present invention, an all-solid-state secondary battery with low resistance and excellent cycle characteristics can be realized.

In the all-solid-state secondary battery 10, the negative electrode active material layer can be a lithium metal layer. Examples of the lithium metal layer include a layer formed by depositing or molding lithium metal powder, a lithium foil, and a lithium vapor-deposited film. The thickness of the lithium metal layer can be, for example, 1 to 500 μm, regardless of the thickness of the negative electrode active material layer.

The positive electrode current collector 5 and the negative electrode current collector 1 are preferably electron conductors.
In the present invention, either or both of the positive electrode current collector and the negative electrode current collector may be simply referred to as a current collector.
Materials for forming the positive electrode current collector include aluminum, aluminum alloy, stainless steel, nickel, and titanium, as well as aluminum or stainless steel whose surface is treated with carbon, nickel, titanium, or silver (to form a thin film). Among them, aluminum and aluminum alloys are more preferable.
Materials for forming the negative electrode current collector include aluminum, copper, copper alloy, stainless steel, nickel, and titanium, as well as carbon, nickel, titanium, or silver treated on the surface of aluminum, copper, copper alloy, or stainless steel. Preferably, aluminum, copper, copper alloys and stainless steel are more preferable.

The shape of the current collector is usually in the form of a film sheet, but nets, punched objects, lath bodies, porous bodies, foam bodies, molded bodies of fiber groups, etc. can also be used.
The thickness of the current collector is not particularly limited, but is preferably 1 to 500 μm. Further, it is also preferable that the surface of the current collector is made uneven by surface treatment.

When the all-solid-state secondary battery 10 has a constituent layer other than the constituent layer formed from the inorganic solid electrolyte-containing composition of the present invention, a layer formed from a known constituent layer forming material can also be applied.
In the present invention, functional layers, members, etc. are appropriately interposed or disposed between or outside each layer of the negative electrode current collector, negative electrode active material layer, solid electrolyte layer, positive electrode active material layer, and positive electrode current collector. You may. Moreover, each layer may be comprised of a single layer or may be comprised of multiple layers.

[Manufacture of all-solid-state secondary batteries]
All-solid-state secondary batteries can be manufactured by conventional methods. Specifically, an all-solid-state secondary battery can be manufactured by forming each of the above layers using the inorganic solid electrolyte-containing composition of the present invention. The details will be explained below.

The all-solid-state secondary battery of the present invention is produced by applying the inorganic solid electrolyte-containing composition of the present invention onto an appropriate base material (for example, metal foil serving as a current collector) to form a coating film (film forming). ) (method for producing an all-solid-state secondary battery sheet of the present invention).
For example, a positive electrode active material layer is formed by applying an inorganic solid electrolyte-containing composition containing a positive electrode active material as a positive electrode material (positive electrode composition) onto a metal foil that is a positive electrode current collector. A positive electrode sheet for the next battery is produced. Next, an inorganic solid electrolyte-containing composition for forming a solid electrolyte layer is applied onto this positive electrode active material layer to form a solid electrolyte layer. Further, on the solid electrolyte layer, an inorganic solid electrolyte-containing composition containing a negative electrode active material is applied as a negative electrode material (negative electrode composition) to form a negative electrode active material layer. By overlaying a negative electrode current collector (metal foil) on the negative electrode active material layer, an all-solid-state secondary battery with a structure in which a solid electrolyte layer is sandwiched between the positive electrode active material layer and the negative electrode active material layer can be obtained. Can be done. This can also be enclosed in a housing to form a desired all-solid-state secondary battery.
In addition, by reversing the formation method of each layer, a negative electrode active material layer, a solid electrolyte layer, and a positive electrode active material layer are formed on the negative electrode current collector, and the positive electrode current collector is stacked to produce an all-solid-state secondary battery. You can also.

Another method is as follows. That is, a positive electrode sheet for an all-solid-state secondary battery is produced as described above. In addition, an inorganic solid electrolyte-containing composition containing a negative electrode active material is applied as a negative electrode material (negative electrode composition) onto a metal foil serving as a negative electrode current collector to form a negative electrode active material layer. A negative electrode sheet for the next battery is produced. Next, a solid electrolyte layer is formed on the active material layer of one of these sheets as described above. Furthermore, the other of the positive electrode sheet for an all-solid-state secondary battery and the negative electrode sheet for an all-solid-state secondary battery is laminated on the solid electrolyte layer so that the solid electrolyte layer and the active material layer are in contact with each other. In this way, an all-solid-state secondary battery can be manufactured.
Another method is the following method. That is, as described above, a positive electrode sheet for an all-solid-state secondary battery and a negative electrode sheet for an all-solid-state secondary battery are produced. Separately, an inorganic solid electrolyte-containing composition is applied onto a base material to produce a solid electrolyte sheet for an all-solid-state secondary battery including a solid electrolyte layer. Further, a positive electrode sheet for an all-solid-state secondary battery and a negative electrode sheet for an all-solid-state secondary battery are laminated so as to sandwich the solid electrolyte layer peeled off from the base material. In this way, an all-solid-state secondary battery can be manufactured.
Furthermore, as described above, a positive electrode sheet for an all-solid-state secondary battery, a negative electrode sheet for an all-solid-state secondary battery, and a solid electrolyte sheet for an all-solid-state secondary battery are produced. Next, the positive electrode sheet for an all-solid-state secondary battery or the negative electrode sheet for an all-solid-state secondary battery and the solid electrolyte sheet for an all-solid-state secondary battery were brought into contact with the positive electrode active material layer or the negative electrode active material layer and the solid electrolyte layer. Stack and pressurize. In this way, the solid electrolyte layer is transferred to the positive electrode sheet for an all-solid-state secondary battery or the negative electrode sheet for an all-solid-state secondary battery. Thereafter, the solid electrolyte layer from which the base material of the solid electrolyte sheet for all-solid-state secondary batteries has been peeled off and the negative electrode sheet for all-solid-state secondary batteries or the positive electrode sheet for all-solid-state secondary batteries (the solid electrolyte layer has a negative electrode active material layer or (with the positive electrode active material layers in contact with each other) and pressurize. In this way, an all-solid-state secondary battery can be manufactured. The pressurizing method, pressurizing conditions, etc. in this method are not particularly limited, and the method, pressurizing conditions, etc. explained below in the pressurization of the applied composition can be applied.

The solid electrolyte layer etc. can be formed by pressure molding an inorganic solid electrolyte-containing composition etc. on the substrate or active material layer under the pressurized conditions described below, or can be formed by sheet molding of the solid electrolyte or active material. You can also use your body.
In the above manufacturing method, the inorganic solid electrolyte-containing composition of the present invention may be used for any one of the positive electrode composition, the inorganic solid electrolyte-containing composition, and the negative electrode composition; It is preferable to use an inorganic solid electrolyte-containing composition, and the inorganic solid electrolyte-containing composition of the present invention can be used for any composition.
When forming a solid electrolyte layer or an active material layer using a composition other than the inorganic solid electrolyte-containing composition of the present invention, examples of the material include commonly used compositions. In addition, materials belonging to Group 1 or Group 2 of the periodic table that accumulate in the negative electrode current collector during initialization or charging during use, as described below, without forming a negative electrode active material layer during manufacturing of all-solid-state secondary batteries. A negative electrode active material layer can also be formed by combining metal ions with electrons and depositing the metal on a negative electrode current collector or the like.

<Formation of each layer (film formation)>
Film formation (coating and drying) of the inorganic solid electrolyte-containing composition of the present invention is carried out while gradually solidifying or precipitating the binder components by hydrogen bonding them within the molecule. The method of forming hydrogen bonds within the molecule is not particularly limited, but includes, for example, a method of selecting drying conditions in the film forming process.
The method of applying the inorganic solid electrolyte-containing composition and the like is not particularly limited and can be selected as appropriate. Examples include coating (preferably wet coating), spray coating, spin coating, dip coating, slit coating, stripe coating, and bar coating. The coating conditions are determined as appropriate, but it is preferable that the above-mentioned components constituting the polymer binder do not chemically react. For example, the temperature condition is preferably lower than the drying temperature described below.

The applied inorganic solid electrolyte-containing composition is dried (heated). In the drying process, polymer C1-1 or C2 of the binder components in the applied inorganic solid electrolyte-containing composition forms intramolecular hydrogen bonds while maintaining adsorption with solid particles, for example, in the form of particles, By solidifying or precipitating, solid particles can be bound together while suppressing an increase in interfacial resistance. This solidification or precipitation of the polymer, combined with the excellent dispersion properties of the inorganic solid electrolyte-containing composition, makes it possible to bind solid particles while suppressing variations in contact conditions and increases in interfacial resistance. A flat coated dry layer can be formed.
In the drying process, when the inorganic solid electrolyte-containing composition of the present invention is heated, the formation of intramolecular hydrogen bonds in the polymer among the binder components is promoted as the temperature increases, and the volatilization of the dispersion medium is also promoted. It is considered that the solubility of the polymer in the dispersion medium gradually decreases. In this way, the binder component solidifies or precipitates as a polymeric binder.

The drying treatment may be performed after each inorganic solid electrolyte-containing composition is applied, or after multilayer application.
Drying conditions are not particularly limited as long as they can cleave intermolecular hydrogen bonds and form intramolecular hydrogen bonds. The drying temperature is appropriately set depending on the type of hydrogen-bonding group (BHa) or (BHb), and is preferably 40°C or higher, more preferably 60°C or higher, and even more preferably 80°C or higher. The upper limit is preferably 300°C or less, more preferably 250°C or less, and even more preferably 200°C or less. By heating in such a temperature range, the dispersion medium can be removed while forming intramolecular hydrogen bonds in the polymer C1-1 or C2 to form a coated dry layer. It is also preferable because the temperature does not become too high and each member of the all-solid-state secondary battery is not damaged. As a result, in an all-solid-state secondary battery, it is possible to exhibit excellent overall performance, and to obtain good binding properties and good ionic conductivity even without pressurization.
When the inorganic solid electrolyte-containing composition of the present invention is coated and dried as described above, solid particles can be bound together while suppressing variations in the contact state, and the coated and dried layer (inorganic solid electrolyte layer) has a flat surface. can be formed.

After applying the inorganic solid electrolyte-containing composition, after stacking the constituent layers, or after producing the all-solid-state secondary battery, it is preferable to pressurize each layer or the all-solid-state secondary battery. Examples of the pressurizing method include a hydraulic cylinder press machine. The pressing force is not particularly limited, and is generally preferably in the range of 5 to 1,500 MPa.
Further, the applied inorganic solid electrolyte-containing composition may be heated at the same time as pressure is applied. The heating temperature is not particularly limited and is generally in the range of 30 to 300°C. It is also possible to press at a temperature higher than the glass transition temperature of the inorganic solid electrolyte. Note that pressing can also be performed at a temperature higher than the glass transition temperature of the polymer binder. However, the temperature generally does not exceed the melting point of this polymer.
Pressurization may be carried out with the coating solvent or dispersion medium dried in advance, or may be carried out with the solvent or dispersion medium remaining.
In addition, each composition may be applied at the same time, and the application|coating drying press may be performed simultaneously and/or sequentially. After coating on separate base materials, they may be laminated by transfer.

The atmosphere during the manufacturing process, for example, during coating, heating or pressurization, is not particularly limited, and may be atmospheric air, dry air (dew point -20°C or less), inert gas (for example, argon gas, helium gas, nitrogen (in gas) etc.
As for the pressing time, high pressure may be applied for a short time (for example, within several hours), or medium pressure may be applied for a long time (one day or more). In cases other than sheets for all-solid-state secondary batteries, for example, in the case of all-solid-state secondary batteries, restraints (screw tightening pressure, etc.) for the all-solid-state secondary battery can also be used in order to continue applying moderate pressure.
The press pressure may be uniform or different with respect to the pressurized portion such as the sheet surface.
The press pressure can be changed depending on the area or film thickness of the pressurized portion. It is also possible to apply different pressures to the same area in stages.
The press surface may be smooth or roughened.

<Initialization>
The all-solid-state secondary battery manufactured as described above is preferably initialized after manufacturing or before use. Initialization is not particularly limited, and can be performed, for example, by performing initial charging and discharging with increased press pressure, and then releasing the pressure until the pressure reaches the general operating pressure for all-solid-state secondary batteries.

[Applications of all-solid-state secondary batteries]
The all-solid-state secondary battery of the present invention can be applied to various uses. There are no particular restrictions on how it can be applied, but for example, when installed in electronic devices, it can be used in notebook computers, pen input computers, mobile computers, e-book players, mobile phones, cordless phone handsets, pagers, handy terminals, mobile fax machines, mobile phones, etc. Examples include copiers, portable printers, headphone stereos, video movies, LCD televisions, handy cleaners, portable CDs, mini discs, electric shavers, walkie talkies, electronic notebooks, calculators, memory cards, portable tape recorders, radios, backup power supplies, etc. Other consumer products include automobiles, electric vehicles, motors, lighting equipment, toys, game equipment, road conditioners, watches, strobes, cameras, and medical equipment (pacemakers, hearing aids, shoulder massagers, etc.). Furthermore, it can be used for various military purposes and space purposes. It can also be combined with solar cells.

The present invention will be described in more detail below based on Examples, but the present invention is not to be construed as being limited thereto. In the following examples, "parts" and "%" expressing compositions are based on mass unless otherwise specified. In the present invention, "room temperature" means 25°C.

1. synthesis of polymers,
A polymer shown by the chemical formula below was synthesized as follows.
First, polymers P-01 to P-07, PD-01, and PD-02 were synthesized as a polymer C1-1 having one type of hydrogen-bonding group (BHa) in a side chain.
[Synthesis Example 1: Synthesis of Polymer P-01]
In a 100 mL graduated cylinder, 28.8 g of dodecyl acrylate (manufactured by Tokyo Kasei Kogyo Co., Ltd.), hydrogen bonding monomer 1 (a monomer that leads to a component containing a urea bond in the side chain in the chemical formula below, J. Am. Chem. Soc., 2012, 134, 8344-8347) and 0.1 g of polymerization initiator V-601 (trade name, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) were added to 36 g of N-methylpyrrolidone. A monomer solution was prepared by dissolving.
Next, 18 g of N-methylpyrrolidone was added to a 300 mL three-necked flask, and the above monomer solution was added dropwise to the flask over 2 hours while stirring with an external heater set at 80°C. After the dropwise addition was completed, the temperature was raised to 90° C. using an external heater, and the mixture was stirred for 2 hours. Thereafter, it was added dropwise to methanol and dried under reduced pressure at 60° C. for 5 hours to obtain acrylic polymer P-01 (mass average molecular weight 60,000) as a solid.

[Synthesis Examples 2 to 7: Synthesis of Polymers P-02 to P-07]
Same as Synthesis Example 1, except that in Synthesis Example 1, a compound was used to guide each component so that the polymers P-02 to P-07 had the composition (type and content of the component) shown in the chemical formula below. Polymers P-02 to P-07 (acrylic polymer or vinyl polymer) were each synthesized in the following manner, and each polymer was obtained as a solid.

[Synthesis Examples 8 and 9: Synthesis of polymers PD-01 and PD-02]
In Synthesis Example 1, the same as Synthesis Example 1 except that compounds were used to guide each component so that polymers PD-01 and PD-02 had the composition (types and content of components) shown in the chemical formula below. Polymers PD-01 and PD-02 (acrylic polymers) were synthesized using the following methods, respectively, and polymers PD-01 and PD-02 were obtained as solids.

Next, polymers P-08 to P-11 were synthesized as polymer C2 having two or more types of hydrogen-bonding groups (BHa) in the side chain and having an SP value of 22.5 or less.
[Synthesis Examples 10 to 13: Synthesis of Polymers P-08 to P-11]
In Synthesis Example 1, the same as Synthesis Example 1 was used, except that a compound was used to guide each component so that Polymers P-08 to P-11 had the composition (type and content of the component) shown in the chemical formula below. Polymers P-08 to P-11 (acrylic polymer or vinyl polymer) were each synthesized in the following manner to obtain polymers P-08 to P-11 as solids.

A low molecular compound C1-2 having a hydrogen bonding group (BHb) and having a CLogP value of 1.5 or more was prepared.
D-01: n-hexanol (manufactured by Tokyo Chemical Industry Co., Ltd.)
D-02: n-dodecanol (manufactured by Tokyo Chemical Industry Co., Ltd.)
D-04: 1-pyrenebutanol (manufactured by Aldrich)
D-05: Cholesterol (manufactured by Fujifilm Wako Pure Chemical Industries)

[D-03: Synthesis of N-dodecylbutanoic acid amide]
100 mL of acetonitrile, 10.0 g of dodecylamine (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.), and 6.0 g of triethylamine (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) were added to a 300 mL 3-neck volumetric flask, and after cooling to 0°C, butyric anhydride was added. (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) 8.5 g was slowly added dropwise so as not to exceed 20°C. Thereafter, the temperature was raised to room temperature and stirred for 3 hours. The resulting reaction solution was filtered and the solvent was distilled off to obtain a crude product of N-dodecylbutanoic acid amide. The obtained crude N-dodecylbutanoic acid amide was purified by silica gel column chromatography to obtain 15.3 g of the target N-dodecylbutanoic acid amide D-03.

Finally, compounds for comparison were prepared or synthesized.

cD-01: n-butanol (manufactured by Fujifilm Wako Pure Chemical Industries)

[Synthesis Example 14: Synthesis of polymers cP-01 and cP-02]
In Synthesis Example 1, the same as Synthesis Example 1 was used, except that compounds were used to guide each component so that polymers cP-01 and cP-02 had the composition (type and content of the components) shown in the chemical formula below. Polymers cP-01 and cP-02 (acrylic polymers) were obtained as solids.
[Synthesis Example 15: Synthesis of polymer cP-03]
Toluene (269.0 g) was charged into a 1-liter three-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube, and the temperature was raised to 80° C. under a nitrogen stream. Next, a monomer solution consisting of methyl methacrylate (150.2 g), lauryl methacrylate (381.6 g), V-601 (5.3 g), and mercaptopropionic acid (4.7 g) was added dropwise to the three-necked flask over 2 hours. The solution was added at a uniform rate so that the solution was completed. After the monomer solution was added dropwise, the mixture was stirred for 2 hours, then the temperature was raised to 95° C., and the mixture was further stirred for 2 hours. Subsequently, p-methoxyphenol (0.3 g), glycidyl methacrylate (31.8 g), and tetrabutylammonium bromide (6.4 g) were added to the obtained reaction mixture, and the mixture was heated to 120°C and stirred for 3 hours. did. Thereafter, the reaction solution was cooled to room temperature, poured into stirring methanol (2 L), and allowed to stand for a while. The solid obtained by decantation of the supernatant liquid was dissolved in butyl butyrate (1200 g), and the solvent was distilled off under reduced pressure to a solid content of 40% to obtain a macromonomer solution.
Next, butyl butyrate (167 g) and a macromonomer solution (112.5 g, solid content 40.0%) were charged into a 1 liter three-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube. The temperature was raised to 80°C under a nitrogen stream. Next, a monomer solution consisting of methyl methacrylate (60.0 g), hydroxyethyl acrylate (45.0 g), diisobutyl ketone (115.5 g), and V-601 (1.5 g) was added to the three-necked flask for 2 hours. The solution was added at a constant speed so that the addition was completed at a constant speed. After the monomer solution was added dropwise, the mixture was stirred for 2 hours, then the temperature was raised to 90° C., and the mixture was further stirred for 2 hours. The resulting reaction mixture was filtered through a 50 μm mesh. In this way, a dispersion T-5 of binder particles cP-03 made of polymer cP-03 and having a solid content concentration of 30% by mass was prepared.

Each synthesized polymer is shown below. The number written at the bottom right of each component indicates the content (% by mass).

Table 1 shows the results of calculating the SP value (unit: MPa ^1/2 ) and mass average molecular weight of each synthesized polymer, and the ClogP value of compound C1-2 based on the above method. For each polymer, the above-mentioned SP value (excluding MM) is the same value as the calculated above-mentioned SP value.

2. Preparation of composition containing binder component (hereinafter referred to as binder solution) Binder solutions shown in Table 1 were prepared using each of the polymers synthesized as described above.
[Preparation Example 1: Preparation of binder solution S-1]
By mixing the solid of polymer P-01 synthesized in Synthesis Example 1 and n-hexanol (D-01) as compound C1-2 at a ratio of 10:1 (mass ratio) and dissolving it in butyl butyrate, binder solution S- 1 (solid content mass 3%) was obtained.
[Preparation Examples 2 to 14: Preparation of binder solutions S-2 to S-11 and T-1 to T-4]
In Preparation Example 1, binder solutions S-2 to S-11 and T -1 to T-4 (solid content 3% by mass) were obtained.

[Preparation Examples 15 and 16: Preparation of binder solutions S-12 and S-13]
By mixing the solid of polymer P-07 synthesized in Synthesis Example 7 and the solid of polymer PD-01 synthesized in Synthesis Example 8 at a ratio of 1:1 (mass ratio) and dissolving it in butyl butyrate, binder solution S-12 is obtained. (solid content mass 3%) was obtained.
Similarly to binder solution S-12, binder solution S-13 (solid content 3% by mass) is a combination of the solid of polymer P-07 synthesized in Synthesis Example 7 and the polymer PD-02 synthesized in Synthesis Example 9. It was prepared by mixing the solids in a 1:1 (mass ratio) and dissolving them in butyl butyrate.

[Preparation Examples 17 to 20: Preparation of binder solutions S-14 to 17]
Binder solution S-14 (solid content: 3% by mass) was obtained by dissolving the solid polymer P-08 synthesized in Synthesis Example 8 in butyl butyrate.
In addition, in preparing binder solution S-14, binder solutions S-15 to S-17 ( Solid content: 3% by mass) were obtained.
In Table 1 below, "-" in each column means that the corresponding component is not included.
Moreover, when a polymer has multiple types of hydrogen-bonding groups (BHa), they are also written using "/".

3. Synthesis of sulfide-based inorganic solid electrolyte [Synthesis example A]
The sulfide-based inorganic solid electrolyte is described by T. Ohtomo, A. Hayashi, M. Tatsumisago, Y. Tsuchida, S. Hama, K. Kawamoto, Journal of Power Sources, 233, (2013), pp231-235, and A. Hayashi, S. Hama, H. Morimoto, M. Tatsumisago, T. Minami, Chem. Lett. , (2001), pp. 872-873.
Specifically, in a glove box under an argon atmosphere (dew point -70°C), 2.42 g of lithium sulfide (Li ₂ S, manufactured by Aldrich, purity >99.98%) and diphosphorus pentasulfide (P ₂ S ₅ , manufactured by Aldrich, purity >99%) was weighed, placed in an agate mortar, and mixed for 5 minutes using an agate pestle. The mixing ratio of Li ₂ S and P ₂ S ₅ was Li ₂ S:P ₂ S ₅ =75:25 in molar ratio.
Next, 66 g of zirconia beads with a diameter of 5 mm were placed in a zirconia 45 mL container (manufactured by Fritsch), the entire amount of the mixture of lithium sulfide and diphosphorus pentasulfide was added, and the container was completely sealed under an argon atmosphere. A container was set in a planetary ball mill P-7 (trade name, manufactured by Fritsch) and mechanical milling was performed at a temperature of 25°C and a rotation speed of 510 rpm for 20 hours to produce a yellow powder of sulfide-based inorganic solid electrolyte. (Li-P-S glass, hereinafter sometimes referred to as LPS) 6.20 g was obtained. The average particle size of the Li-P-S glass was 15 μm.

[Example 1]
Each of the compositions shown in Tables 2-1 to 2-3 (collectively referred to as Table 2) was prepared as follows.
In each composition prepared, the binder component was dissolved in the dispersion medium.
<Preparation of inorganic solid electrolyte-containing composition>
60 g of zirconia beads with a diameter of 5 mm were placed in a zirconia 45 mL container (manufactured by Fritsch), and 8.7 g of LPS synthesized in Synthesis Example A above was added to each binder solution or binder shown in the "Binder solution or dispersion" column of Table 2. 0.3 g of the dispersion liquid (solid content mass) and butyl butyrate as a dispersion medium were added so that the content of butyl butyrate in the composition was 55% by mass. Thereafter, this container was set in a planetary ball mill P-7 (trade name) manufactured by Fritsch. The mixture was mixed for 10 minutes at a temperature of 25° C. and a rotation speed of 150 rpm to prepare inorganic solid electrolyte-containing compositions (slurries) K-1 to K-17 and Kc1 to Kc5, respectively.

<Preparation of positive electrode composition>
60 g of zirconia beads with a diameter of 5 mm were placed in a zirconia 45 mL container (manufactured by Fritsch), and 8.0 g of LPS synthesized in Synthesis Example A and each binder solution or dispersion shown in the "Binder solution or dispersion" column of Table 2 were added. 0.4 g (solid mass) of the binder dispersion was added. This container was set in a planetary ball mill P-7 (trade name) manufactured by Fritsch, and stirred at 25° C. and a rotational speed of 200 pm for 30 minutes. Thereafter, in this container, 27.5 g of NMC (manufactured by Aldrich) as a positive electrode active material, 1.0 g of acetylene black (AB) as a conductive agent, and butyl butyrate as a dispersion medium were added in a composition containing 26% by mass. Add butyl butyrate as a dispersion medium, set the container in a planetary ball mill P-7, and continue mixing at a temperature of 25°C and a rotation speed of 200 rpm for 30 minutes to form a positive electrode composition (slurry) PK-1 to PK-17. and PKc1 to PKc5 were prepared, respectively.

<Preparation of negative electrode composition>
60 g of zirconia beads with a diameter of 5 mm were placed in a zirconia 45 mL container (manufactured by Fritsch), and 8.0 g of LPS synthesized in Synthesis Example A was added to each binder solution or binder dispersion shown in the "Binder solution or dispersion" column of Table 2. 0.4 g (solid mass) of liquid was added. This container was set in a planetary ball mill P-7 (trade name) manufactured by Fritsch, and mixed for 60 minutes at a temperature of 25° C. and a rotation speed of 300 pm. After that, the content in the composition of 9.5 g of silicon (Si, manufactured by Aldrich) as a negative electrode active material, 1.0 g of VGCF (manufactured by Showa Denko) as a conductive agent, and butyl butyrate as a dispersion medium was adjusted to 48% by mass. Butyl butyrate was added as a dispersion medium, and similarly, the container was set in a planetary ball mill P-7, and mixed for 10 minutes at a temperature of 25°C and a rotation speed of 100 rpm to form a negative electrode composition (slurry) NK-1. -NK-17 and NKc1 to NKc5 were prepared, respectively.

<Table abbreviations>
LPS: LPS synthesized in Synthesis Example A
NMC: LiNi _1/3 Co _1/3 Mn _1/3 O ₂
AB: Acetylene black Si: Silicon VGCF: Carbon nanotube "SP value difference" in the table indicates an absolute value, and the unit is MPa ^1/2 . When the composition contains a plurality of polymers, the difference between the SP values of each polymer is also written using a "/".
The unit of "composition content" and "solid content" is "mass %".

<Preparation of solid electrolyte sheet for all-solid-state secondary battery>
Each of the inorganic solid electrolyte-containing compositions shown in the "Solid electrolyte composition No." column of Table 3-1 obtained above was applied onto a 20 μm thick aluminum foil using a Baker applicator (product name: SA-201, Tester). (manufactured by Sangyo Co., Ltd.) and heated at 80° C. for 2 hours to dry the inorganic solid electrolyte-containing composition (at this time, the formation of intramolecular hydrogen bonds in the binder components is promoted). Thereafter, using a heat press machine, the dried inorganic solid electrolyte-containing composition was heated and pressurized at a temperature of 120°C and a pressure of 40 MPa for 10 seconds to form a solid electrolyte sheet for an all-solid secondary battery (Table 3- In No. 1, it is written as a solid electrolyte sheet.) No. 101-117 and c11-c15 were produced, respectively. The thickness of the solid electrolyte layer was 45 μm.

<Production of positive electrode sheet for all-solid-state secondary battery>
Each of the positive electrode compositions shown in the "Positive electrode composition No." column of Table 3-2 obtained above was applied onto a 20 μm thick aluminum foil using a Baker applicator (trade name: SA-201), The positive electrode composition was dried by heating at 80° C. for 1 hour and then at 110° C. for 1 hour (at this time, the formation of intramolecular hydrogen bonds in the binder components was promoted). Thereafter, the dried positive electrode composition was pressurized (10 MPa, 1 minute) at 25°C using a heat press machine to form a positive electrode sheet for an all-solid-state secondary battery having a positive electrode active material layer with a film thickness of 80 μm (front side). (referred to as positive electrode sheet in 3-2) No. Nos. 118 to 134 were produced, respectively.

<Production of negative electrode sheet for all-solid-state secondary battery>
Each negative electrode composition shown in the "Negative electrode composition No." column of Table 3-3 obtained above was applied onto a 20 μm thick copper foil using a Baker applicator (product name: SA-201). The negative electrode composition was dried by heating at 80° C. for 1 hour, and then at 110° C. for 1 hour (at this time, the formation of intramolecular hydrogen bonds in the binder components was promoted). Thereafter, the dried negative electrode composition was pressurized (10 MPa, 1 minute) at 25°C using a heat press machine to form an all-solid-state secondary battery negative electrode sheet (front side) having a negative electrode active material layer with a thickness of 70 μm. In 3-3, it is written as negative electrode sheet.) No. 135-151 and c17-c21 were produced, respectively.

<Evaluation 1: Dispersion stability>
Each of the prepared compositions (slurry) was poured into a glass test tube with a diameter of 10 mm and a height of 4 cm to a height of 4 cm, and allowed to stand at 25° C. for 15 hours. The solid content ratio for 1 cm from the slurry liquid level before and after standing was calculated. Specifically, immediately after the slurry was allowed to stand still, a portion of the slurry up to 1 cm below the surface of the slurry was taken out and dried by heating at 120° C. for 2 hours in an aluminum cup. After that, the mass of the solid content in the cup was measured to determine the respective solid content before and after standing still. The thus obtained solid content ratio [WA/WB] of the solid content WA after standing to the solid content WB before standing was determined.
The ease with which the inorganic solid electrolyte settles (sedimentability) was evaluated as the dispersion stability of the solid electrolyte composition, depending on which of the following evaluation criteria this solid content ratio was included in. In this test, the closer the solid content ratio is to 1, the better the dispersion stability is, and the evaluation standard "B" or higher is a passing level. The results are shown in Table 1.

- Evaluation criteria -
A: 0.9≦solid content ratio≦1.0
B: 0.5≦solid content ratio<0.9
C: 0.3≦solid content ratio<0.5
D: Solid content ratio <0.3

<Evaluation 2: Surface smoothness>
Test pieces measuring 20 mm in length x 20 mm in width were cut out from each solid electrolyte sheet for all-solid secondary batteries, each positive electrode sheet for all-solid secondary batteries, and each negative electrode sheet for all-solid secondary batteries. Regarding this test piece, the layer thickness was measured at 5 points using a constant pressure thickness measuring device (manufactured by Techlock Co., Ltd.), and the arithmetic mean value of the layer thickness was calculated.
From each measured value and its arithmetic average value, the larger deviation value (maximum deviation value) among the deviation values (%) obtained by the following formula (a) or (b) is applied to the following evaluation criteria to evaluate the surface smoothness. evaluated. In this test, the smaller the maximum deviation value (%), the more uniform the layer thickness of the solid electrolyte layer or the active material layer is, that is, the more uniform the layer thickness of the solid electrolyte layer or the active material layer is, the more each composition exhibits appropriate viscosity (fluidity) and the surface of the film formed is This shows that it is possible to form a flat coating film. In this exam, an evaluation standard of "B" or higher is considered a passing level. The results are shown in Table 3-1, Table 3-2, and Table 3-3 (collectively referred to as Table 3).

Formula (a): 100 x (maximum value of layer thickness at 5 points - arithmetic mean value) / (arithmetic mean value)
Formula (b): 100 x (arithmetic mean value of layer thickness at 5 points - minimum value) / (arithmetic mean value)

The layer thickness was measured at the following "5 points" for each test piece.
As shown in FIG. 3, first, three imaginary lines y1, y2, and y3 are drawn to divide the test piece TP in the vertical direction into four equal parts, and then, in the same way, the horizontal direction of the test piece TP is divided into four equal parts. Three imaginary lines x1, x2, and x3 are drawn to divide the surface of the test piece into a grid pattern.
The measurement points are intersection A between virtual lines x1 and y1, intersection B between virtual lines x1 and y3, intersection C between virtual lines x2 and y2, intersection D between virtual lines x3 and y1, and virtual lines x3 and y3. Let the intersection point E be.

- Evaluation criteria -
A: Maximum deviation value < 3%
B: 3%≦maximum deviation value<8%
C: 8%≦maximum deviation value<13%
D: 13%≦maximum deviation value

<Manufacture of all-solid-state secondary batteries>
An all-solid-state secondary battery (No. 101) having the layer structure shown in FIG. 1 was produced in the following manner.

(Preparation of positive electrode sheet for all-solid-state secondary battery with solid electrolyte layer)
Next, on the positive electrode active material layer of each positive electrode sheet for all-solid-state secondary batteries shown in the "Electrode active material layer" column of Table 4, the solid electrolyte sheet shown in the "Solid electrolyte layer" column of Table 4 produced above was applied. are stacked so that the solid electrolyte layer is in contact with the cathode active material layer, and transferred (laminated) using a press machine by applying a pressure of 50 MPa at 25°C, and then applying a pressure of 600 MPa at 25°C to form a solid electrolyte layer with a film thickness of 30 μm. Positive electrode sheets 118 to 134 (positive electrode active material layer thickness: 60 μm) for all-solid-state secondary batteries were each prepared.

(Preparation of negative electrode sheet for all-solid-state secondary battery with solid electrolyte layer)
Next, on the negative electrode active material layer of each negative electrode sheet for all solid-state secondary batteries shown in the "Electrode active material layer" column of Table 4, the solid electrolyte sheet shown in the "Solid electrolyte layer" column of Table 4 produced above was applied. were stacked so that the solid electrolyte layer was in contact with the negative electrode active material layer, and after transfer (lamination) using a press machine and applying a pressure of 50 MPa at 25°C, a pressure of 600 MPa was applied at 25°C to form a solid electrolyte layer with a film thickness of 30 μm. Negative electrode sheets 135 to 151 and c17 to c21 (negative electrode active material layer thickness: 50 μm) for all-solid-state secondary batteries were respectively produced.

(Manufacture of all-solid-state secondary batteries)
1. All-solid-state secondary battery No. Manufacture of Nos. 101 to 117 All-solid-state secondary battery positive electrode sheet No. 1 equipped with the solid electrolyte layer obtained above. 118 (the aluminum foil of the solid electrolyte-containing sheet has been peeled off) is cut into a disc shape with a diameter of 14.5 mm, and as shown in Figure 2, a stainless steel 2032 is assembled with a spacer and a washer (not shown in Figure 2). I put it in a coin case 11. Next, a lithium foil cut out into a disk shape with a diameter of 15 mm was placed on the solid electrolyte layer. After further layering stainless steel foil on top of it, by caulking the 2032 type coin case 11, the No. 2 coin case shown in FIG. 101 all-solid-state secondary batteries 13 were manufactured. The all-solid-state secondary battery (half cell) manufactured in this way has the layer structure shown in FIG. 1 (however, the lithium foil corresponds to the negative electrode active material layer 2 and the negative electrode current collector 1).

In manufacturing the all-solid-state secondary battery (No. 101), all-solid-state secondary battery positive electrode sheet No. 1 including a solid electrolyte layer was manufactured. No. 118 shown in the "electrode active material layer" column of Table 4 was used instead of No. 118. An all-solid-state secondary battery (half cell) was produced in the same manner as the all-solid-state secondary battery (No. 101), except that a positive electrode sheet for an all-solid-state secondary battery with a solid electrolyte layer represented by was used. No. Nos. 102 to 117 were produced, respectively.

2. All-solid-state secondary battery No. Manufacture of 118 to 134 and c101 to c105 Negative electrode sheet No. 1 for all-solid secondary batteries equipped with the solid electrolyte layer obtained above. 135 (the aluminum foil of the solid electrolyte-containing sheet has been peeled off) is cut into a disk shape with a diameter of 14.5 mm, and as shown in FIG. 2, a stainless steel 2032 is assembled with a spacer and a washer (not shown in FIG. 2). I put it in a coin case 11. Next, a positive electrode sheet (positive electrode active material layer) punched out with a diameter of 14.0 mm from the positive electrode sheet for an all-solid-state secondary battery produced below was stacked on the solid electrolyte layer. After further layering stainless steel foil on top of it, by caulking the 2032 type coin case 11, all-solid-state secondary battery (full cell) No. 1 shown in FIG. 118 was produced.

A positive electrode sheet for a solid secondary battery used for manufacturing an all-solid secondary battery (No. 118) was prepared as follows.
(Preparation of positive electrode composition)
180 zirconia beads with a diameter of 5 mm were placed in a 45 mL zirconia container (manufactured by Fritsch), 2.7 g of LPS synthesized in Synthesis Example A above, and KYNAR FLEX 2500-20 (trade name, PVdF-HFP: polyfluoride). A solid content of 0.3 g of vinylidene hexafluoropropylene copolymer (manufactured by Arkema) and 22 g of butyl butyrate were added. This container was set in a planetary ball mill P-7 (trade name) manufactured by Fritsch, and stirred at 25° C. and a rotation speed of 300 rpm for 60 minutes. After that, 7.0 g of LiNi _1/3 Co _1/3 Mn _1/3 O ₂ (NMC) was added as a positive electrode active material, and in the same manner, the container was set in a planetary ball mill P-7 and heated at 25°C and the rotation speed. Mixing was continued for 5 minutes at 100 rpm to prepare a positive electrode composition.
(Preparation of positive electrode sheet for solid secondary battery)
The positive electrode composition obtained above was applied onto a 20 μm thick aluminum foil (positive electrode current collector) using a Baker applicator (trade name: SA-201, manufactured by Tester Sangyo Co., Ltd.), and heated at 100°C for 2 hours. , the positive electrode composition was dried (the dispersion medium was removed). Thereafter, the dried positive electrode composition was pressurized at 25° C. (10 MPa, 1 minute) using a heat press machine to produce a positive electrode sheet for an all-solid-state secondary battery having a positive electrode active material layer with a film thickness of 80 μm. .

The above all-solid-state secondary battery No. In the production of No. 118, an all-solid-state secondary battery negative electrode sheet with a solid electrolyte layer was manufactured. No. 135 shown in the "electrode active material layer" column of Table 4 was used instead of No. 135. All-solid-state secondary battery No. 1 was used except that an all-solid-state secondary battery negative electrode sheet having a solid electrolyte layer represented by the following was used. All-solid-state secondary battery (full cell) No. 118 was manufactured in the same manner as No. 118. 119-134 and c101-c105 were produced, respectively.

<Evaluation 3: Cycle characteristic test>
The discharge capacity retention rate of each manufactured all-solid-state secondary battery was measured using a charge-discharge evaluation device TOSCAT-3000 (trade name, manufactured by Toyo System Co., Ltd.).
Specifically, each all-solid-state secondary battery was charged in a 25° C. environment at a current density of 0.1 mA/cm ² until the battery voltage reached 3.6 V. Thereafter, the battery was discharged at a current density of 0.1 mA/cm ² until the battery voltage reached 2.5 V. One charge and one discharge constituted one charge/discharge cycle, and the charge/discharge was repeated for three cycles under the same conditions for initialization. Thereafter, the above charge/discharge cycle was repeated, and each time the charge/discharge cycle was performed, the discharge capacity of each all-solid-state secondary battery was measured using a charge/discharge evaluation device: TOSCAT-3000 (trade name).
When the discharge capacity of the first charge/discharge cycle after initialization (initial discharge capacity) is 100%, the number of charge/discharge cycles when the discharge capacity retention rate (discharge capacity relative to the initial discharge capacity) reaches 80% is The battery performance (cycle characteristics) was evaluated based on which of the following evaluation criteria the battery was included in. In this test, the higher the evaluation standard, the better the battery performance (cycle characteristics), and the ability to maintain the initial battery performance even after repeated charging and discharging multiple times (even during long-term use). The passing level for this exam is the evaluation standard "C" or higher. The all-solid-state secondary battery c103 was included in the evaluation standard "D", but the number of charge/discharge cycles was 90.
In addition, all-solid-state secondary battery No. The initial discharge capacities of Nos. 101 to 134 all showed values sufficient to function as all-solid-state secondary batteries.

- Evaluation criteria -
A: 500 cycles or more B: 250 cycles or more, less than 500 cycles C: 150 cycles or more, less than 250 cycles D: 80 cycles or more, less than 150 cycles E: Less than 80 cycles

<Evaluation 4: Ionic conductivity measurement>
The ionic conductivity of each manufactured all-solid-state secondary battery was measured. Specifically, for each all-solid-state secondary battery, AC impedance was measured at a voltage amplitude of 5 mV and a frequency of 1 MHz to 1 Hz using a 1255B FREQUENCY RESPONSE ANALYZER (trade name, manufactured by SOLARTRON) in a constant temperature bath at 30°C. Thereby, the resistance in the layer thickness direction of the sample for ionic conductivity measurement was determined, and the ionic conductivity was determined by calculation using the following formula (1).

Formula (1): Ionic conductivity σ (mS/cm) =
1000×sample layer thickness (cm)/[resistance (Ω)×sample area (cm ² )]

In formula (1), the sample layer thickness is measured before putting the laminate 12 into the 2032 type coin case 11, and the value obtained by subtracting the layer thickness of the current collector (the total layer thickness of the solid electrolyte layer and the electrode active material layer) ). The sample area is the area of a disc-shaped sheet with a diameter of 14.5 mm.
It was determined which of the following evaluation criteria the obtained ionic conductivity σ was included in.
Regarding the ionic conductivity σ in this test, an evaluation standard of "C" or higher means a pass. The all-solid-state secondary battery c103 was included in the evaluation standard "D", but the ionic conductivity σ was 0.20 (mS/cm).

- Evaluation criteria -
A: 0.60≦σ
B: 0.50≦σ<0.60
C: 0.30≦σ<0.50
D: 0.20≦σ<0.30
E: σ<0.20

The following can be seen from the results shown in Tables 3 and 4.
All inorganic solid electrolyte-containing compositions that do not contain the binder component specified in the present invention have poor dispersion stability, and the constituent layers formed using these compositions exhibit large coating thickness unevenness. It can be seen that the surface smoothness is also poor. Moreover, all-solid-state secondary batteries using these compositions, which are inferior in dispersion stability and surface smoothness, do not exhibit sufficient ionic conductivity or cycle characteristics.
On the other hand, all inorganic solid electrolyte-containing compositions containing the binder component specified in the present invention have both high levels of dispersion stability and surface smoothness. By using this inorganic solid electrolyte-containing composition to form a constituent layer of an all-solid-state secondary battery, it is possible to form a constituent layer with a flat surface and low resistance, and the resulting all-solid-state secondary battery has excellent cycle characteristics. It can be seen that high ionic conductivity can be achieved. The above-mentioned effects of the present invention are such that the binder component forms intermolecular hydrogen bonds in the inorganic solid electrolyte-containing composition, dissolves in the dispersion medium, and exhibits excellent dispersion properties; This is thought to be because a polymer binder is formed by forming internal hydrogen bonds, and the solid particles can be bound together while suppressing an increase in interfacial resistance.
Since the all-solid-state secondary battery of the present invention exhibits the above-mentioned excellent characteristics, it exhibits excellent cycle characteristics even under high-speed charging and discharging conditions.

Although the invention has been described in conjunction with embodiments thereof, we do not intend to limit our invention in any detail in the description unless otherwise specified and contrary to the spirit and scope of the invention as set forth in the appended claims. I believe that it should be interpreted broadly without any restrictions.

This application claims priority based on Japanese Patent Application No. 2020-110647, which was filed in Japan on June 26, 2020, and the contents thereof are incorporated herein by reference. Incorporate it as a part.

1 Negative electrode current collector 2 Negative electrode active material layer 3 Solid electrolyte layer 4 Positive electrode active material layer 5 Positive electrode current collector 6 Operating part 10 All-solid-state secondary battery 11 2032 type coin case 12 All-solid-state secondary battery laminate 13 Coin type All-solid-state secondary battery TP test piece

Claims (11)

An inorganic solid electrolyte-containing composition comprising an inorganic solid electrolyte having ion conductivity of a metal belonging to Group 1 or 2 of the Periodic Table, a component constituting a polymer binder, and a dispersion medium,
An inorganic solid electrolyte-containing composition, wherein the component constituting the polymer binder contains a compound defined in at least one of the following (C1) to (C3).
(C1) A polymer having an SP value of 21.0 MPa ^1/2 or less among polymer C1-1 having at least one type of hydrogen bonding group (BHa) in a side chain that can form two or more hydrogen bonds, and active hydrogen A compound C1-2 having a CLogP value of 1.5 or more, which has a hydrogen bonding group (BHb) containing the active hydrogen atom and capable of forming a hydrogen bond with the hydrogen bonding group (BHa).
(C2) A polymer having two or more types of hydrogen-bonding groups (BHa) capable of forming two or more hydrogen bonds in its side chain, and having an SP value of 22.5 MPa ^1/2 or less Polymer C2
(C3) Two or more types of polymers dissolved in the dispersion medium among the polymers C1-1, or one or more types of the polymers C1-1 and one or more types of the polymers C2 The inorganic solid electrolyte-containing composition according to claim 1, wherein the polymer C1-1 or C2 has a component derived from a (meth)acrylic monomer or a vinyl monomer. The inorganic solid electrolyte-containing composition according to claim 2, wherein the hydrogen bonding group (BHa) is introduced into the constituent component. The inorganic solid electrolyte-containing composition according to any one of claims 1 to 3, wherein the inorganic solid electrolyte is a sulfide-based inorganic solid electrolyte. The inorganic solid electrolyte-containing composition according to any one of claims 1 to 4, wherein the dispersion medium contains at least one selected from ketone compounds, aliphatic compounds, and ester compounds. The inorganic solid electrolyte-containing composition according to any one of claims 1 to 5, which contains an active material. The inorganic solid electrolyte-containing composition according to any one of claims 1 to 6, which contains a conductive aid. An all-solid-state secondary battery sheet comprising a layer made of the inorganic solid electrolyte-containing composition according to any one of claims 1 to 7. An all-solid-state secondary battery comprising a positive electrode active material layer, a solid electrolyte layer, and a negative electrode active material layer in this order,
At least one layer of the positive electrode active material layer, the solid electrolyte layer, and the negative electrode active material layer is a layer composed of the inorganic solid electrolyte-containing composition according to any one of claims 1 to 7. solid state secondary battery. A method for manufacturing an all-solid-state secondary battery sheet, which comprises forming a film from the inorganic solid electrolyte-containing composition according to any one of claims 1 to 7. A method for manufacturing an all-solid-state secondary battery, comprising manufacturing an all-solid-state secondary battery by the manufacturing method according to claim 10.

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