JP2018106844A - Binder for all-solid battery and all-solid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a binder for an all-solid battery, which is superior in safety to conventional ones; and an all-solid battery arranged by use of the binder.SOLUTION: Disclosed are a binder for an all solid battery and an all-solid battery comprising the binder. The all solid battery 100 has a positive electrode 40, a negative electrode 30, and a solid electrolyte between the positive electrode 40 and the negative electrode 30, in which at least any one of the positive electrode 40, the negative electrode 30, and the solid electrolyte includes the binder. The binder comprises a polymer material having primarily a repeating unit including, in its side chain, a terminal substituent of at least any one of a t-butoxycarbonyl group and a t-butoxy carbonyloxy group.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a binder for an all-solid battery that is superior in safety to conventional ones, and an all-solid battery using the same.

  An all-solid battery is a battery in which the positive electrode, the negative electrode, and the electrolyte layer between the two electrodes are all made of solid. The all-solid-state battery is expected as a battery capable of simplifying the safety mechanism because there is no risk of electrolyte leakage or ignition as compared with a conventional battery using a liquid electrolyte. However, even if it is an all-solid-state battery, for example, a sulfide solid battery or the like is required to have higher safety because the sulfide solid electrolyte in the battery can react with moisture to generate hydrogen sulfide.

  Patent Document 1 discloses an all-solid battery in which a positive electrode layer is formed by mixing sulfur (S), which is a positive electrode active material, a sulfide-based lithium ion conductive solid electrolyte, and conductive carbon. It is disclosed. In this document, since the positive electrode layer includes a sulfide-based lithium ion conductive solid electrolyte, a combination of an electrolyte layer composed of an oxide-based lithium ion conductive solid electrolyte and sulfur that is a positive electrode active material, There is a description that battery performance can be improved.

JP 2014-029777 A

However, the all-solid-state battery as disclosed in Patent Document 1 may increase the battery temperature due to a short circuit between electrodes or overcharge. This is because when the electrodes are short-circuited, a large discharge current continues to flow, so that a discharge reaction or an overdischarge reaction proceeds. Further, in overcharging, the charging current is excessively supplied from the outside, and the decomposition reaction of the battery material proceeds. In all solid lithium batteries, a method for suppressing such an exothermic reaction is required.
The present disclosure has been accomplished in view of the above circumstances, and an object of the present disclosure is to provide a binder for an all-solid battery that is superior to conventional ones and an all-solid battery using the same.

  The binder for all-solid-state batteries of this indication is characterized by including the polymeric material which has as a main repeating unit the structural unit shown by following General formula (1).

(In the general formula (1), A ¹ , A ² , A ³ and A ⁴ are independently of each other,
Single bond, or
A linear aliphatic hydrocarbon group having 1 to 8 carbon atoms,
A branched C3-C8 acyclic aliphatic hydrocarbon group,
A C3-C8 cyclic aliphatic hydrocarbon group which may have a side chain,
An aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a side chain, a group formed by connecting an aromatic hydrocarbon group and an aliphatic hydrocarbon group having 7 to 14 carbon atoms in total, and ,
A group selected from the group consisting of groups in which some of the atoms constituting these hydrocarbon groups are substituted with heteroatoms is shown.
B ¹ , B ² , B ³ and B ⁴ each independently represent a single bond or an oxygen atom.
p, q and r each represents an integer of 0 or 1. However, when B ¹ is a single bond, p + q + r ≧ 1. )

  In the present disclosure, the number average molecular weight Mn of the polymer material may be 5,000 or more and 200,000 or less.

  In the present disclosure, in the polymer material, the repeating number of the main repeating unit may be 25 or more and 1,000 or less.

  In the present disclosure, the onset temperature of mass decrease in the TG curve of the polymer material obtained by simultaneous differential thermal-thermogravimetric analysis based on JISK 0129: 2005 may be 150 ° C. or higher and 220 ° C. or lower.

In the present disclosure, it may be 99% or less mass reduction rate M _L of the polymeric material obtained 40% or more by the following formula (A).
Formula _{(A) M L = (m} 150 ℃ -m 220 ℃ / m 150 ℃) × 100
(In the above formula (A), _{M L} is a mass reduction rate of the polymer material _{(%), m 150 ℃} is JISK 0129: a differential thermal conforms to 2005 - of the polymer material obtained by thermogravimetric simultaneous analysis (The mass (mg) at 150 ° C. in the TG curve, and m _{220 ° C.} represents the mass (mg) at 220 ° C. in the TG curve.)

  In the present disclosure, the polymer material may have a structural unit represented by the following general formula (1A) as a main repeating unit.

(In the above general formula (1A), A ^1a , A ^2a , A ^3a and A ^4a are independently of each other,
Single bond, or
Methylene group (—CH ₂ —), ethylene group (—CH ₂ CH ₂ —), trimethylene group (—CH ₂ CH ₂ CH ₂ —), propylene group (—CH (CH ₃ ) CH ₂ —), 1, 4 -A hydrocarbon group selected from the group consisting of a cyclohexylene group, a 1,2-phenylene group, a 1,4-phenylene group, and a 4,4'-biphenylene group.
p _a , q _a, and r _a represent an integer of 0 or 1, and p _a + q _a + r _a ≧ 1. )

  In the present disclosure, the polymer material may have a structural unit represented by the following general formula (1B) as a main repeating unit.

(In the above general formula (1B), A ^1b , A ^2b , A ^3b and A ^4b are independent of each other,
Single bond, or
Methylene group (—CH ₂ —), ethylene group (—CH ₂ CH ₂ —), trimethylene group (—CH ₂ CH ₂ CH ₂ —), propylene group (—CH (CH ₃ ) CH ₂ —), 1, 4 -A hydrocarbon group selected from the group consisting of a cyclohexylene group, a 1,2-phenylene group, a 1,4-phenylene group, and a 4,4'-biphenylene group.
p _{b, q b} and _{r b} are each independently an integer of 0 or 1. )

  The all-solid-state battery of this indication has a positive electrode, a negative electrode, and the solid electrolyte which exists between a positive electrode and a negative electrode, and at least any one of a positive electrode, a negative electrode, and a solid electrolyte is the said Claim 1 thru | or 7 It contains the binder for all-solid-state batteries as described in any one.

  According to the binder of the present disclosure, since it includes a polymer material mainly having a repeating unit containing at least one terminal substituent of a t-butoxycarbonyl group and a t-butoxycarbonyloxy group in a side chain, When used in an all-solid-state battery, a gas derived from decomposition of the terminal substituent is generated before the surface temperature of the all-solid-state battery reaches a specific temperature. As a result, an all-solid battery having higher safety than the conventional one can be obtained.

It is a plane schematic diagram of one embodiment of the all-solid battery of the present disclosure. It is a cross-sectional schematic diagram of one Embodiment of the all-solid-state battery of this indication, and is a figure which shows the AA cross section in FIG. It is a cross-sectional schematic diagram of one embodiment of the all-solid battery of the present disclosure, and is a schematic cross-sectional view showing a state where the internal terminal 31 and the external terminal 32 are peeled off due to the generation of a small molecule gas. It is the graph which piled up and showed each mass reduction rate of polymer 1 to polymer 4.

1. Binder for all-solid-state battery A binder for all-solid-state battery according to the present disclosure includes a polymer material having a structural unit represented by the following general formula (1) as a main repeating unit.

In the general formula (1), A ¹ , A ² , A ³ and A ⁴ are each independently a single bond or a linear aliphatic hydrocarbon group having 1 to 8 carbon atoms and a carbon having a branch. A 3 to 8 acyclic aliphatic hydrocarbon group, a C 3-8 cyclic aliphatic hydrocarbon group that may have a side chain, and a C 6-12 carbon chain that may have a side chain Aromatic hydrocarbon groups, groups having a total carbon number of 7 to 14 formed by linking aromatic hydrocarbon groups and aliphatic hydrocarbon groups, and some of the atoms constituting these hydrocarbon groups are heteroatoms Represents a group selected from the group consisting of groups substituted by
B ¹ , B ² , B ³ and B ⁴ each independently represent a single bond or an oxygen atom.
p, q and r each represents an integer of 0 or 1. However, when B ¹ is a single bond, p + q + r ≧ 1.

B ¹ , B ² , B ³ and B ⁴ determine the substituent structure at the end of the side chain of the polymeric material. For example, when B ¹ is a single bond, the terminal substituent bonded to A ¹ is a t-butoxycarbonyl group. For example, when B ¹ is an oxygen atom, the terminal substituent bonded to A ¹ is a t-butoxycarbonyloxy group. ^This also applies to B 2 .about.B ^4.
Since B ¹ , B ² , B ³ and B ⁴ are independent of each other, the terminal substituent in the repeating unit may be only a t-butoxycarbonyl group or only a t-butoxycarbonyloxy group. Both of these two groups may be contained in the repeating unit.
Both the t-butoxycarbonyl group and the t-butoxycarbonyloxy group are decomposed into relatively stable compounds such as isobutene and carbon dioxide at a high temperature. Therefore, in the present disclosure, when such an easily decomposable terminal substituent is incorporated in the polymer material in advance, when the all-solid battery including the polymer material generates heat, the terminal substituent is derived from the decomposition. The generation of gas to make it easier to detect the heat generation of the battery. In particular, when a battery reaction stop structure as described later is provided in an all-solid battery, the current can be cut off by gas generation, and the heat generation of the battery can be suppressed.

A ¹ , A ² , A ^3, and A ⁴ each serve as a linker that connects the terminal substituent (t-butoxycarbonyl group or t-butoxycarbonyloxy group) and the carbon atom in the main chain skeleton. As described above, since the terminal substituent is mainly responsible for gas generation, these linkers are not particularly limited as long as they are usually used as the side chain structure of the binder and do not interfere with gas generation under high temperature.
Since A ¹ , A ² , A ³ and A ⁴ are independent of each other, the structure of the linker can be freely designed.
Will be mainly described hereinafter ^{A 1} as an example, the following description applies for ^A 2 to A ^4.

When A ¹ is a single bond, the terminal substituent and the carbon atom in the main chain skeleton are directly bonded.
On the other hand, a hydrocarbon group can be adopted as A ¹ and the terminal substituent and the carbon atom in the main chain skeleton can be connected by a hydrocarbon group. Examples of the hydrocarbon group that can be used include a linear aliphatic hydrocarbon group having 1 to 8 carbon atoms, a branched acyclic aliphatic hydrocarbon group having 3 to 8 carbon atoms, and carbon that may have a side chain. A cyclic aliphatic hydrocarbon group having 3 to 8 carbon atoms, an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a side chain, and an aromatic hydrocarbon group and fat having 7 to 14 carbon atoms in total And a group formed by linking with a group hydrocarbon group.

The straight-chain aliphatic hydrocarbon group having 1 to 8 carbon atoms includes both saturated hydrocarbon groups and unsaturated hydrocarbon groups. Specific examples of the linear aliphatic hydrocarbon group having 1 to 8 carbon atoms include a methylene group (—CH ₂ —), an ethylene group (—CH ₂ CH ₂ —), and a trimethylene group (—CH ₂ CH ₂ CH). _A linear saturated hydrocarbon group such as _2- ); vinylene group (—CH═CH—), —CH═CHCH ₂ —, and —CC— (a group in which carbon atoms are bonded by a triple bond). Linear unsaturated hydrocarbon groups such as; and the like. Among these, a methylene group, an ethylene group, a trimethylene group, and the like may be particularly used.
The branched C3-C8 acyclic aliphatic hydrocarbon group includes both saturated hydrocarbon groups and unsaturated hydrocarbon groups. Specific examples of the branched acyclic aliphatic hydrocarbon group having 3 to 8 carbon atoms include a propylene group (—CH (CH ₃ ) CH ₂ —) and a methylvinylene group (—C (CH ₃ ) ═CH—). Etc. Among these, a propylene group may be particularly used.
The C 3-8 cycloaliphatic hydrocarbon group includes both saturated hydrocarbon groups and unsaturated hydrocarbon groups. Examples of the ring structure in the cyclic aliphatic hydrocarbon group include a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, and a cyclohexane ring. The cyclic aliphatic hydrocarbon group may have a side chain, and examples of the side chain include a methyl group, an ethyl group, and a propyl group. Specific examples of the cyclic aliphatic hydrocarbon group having 3 to 8 carbon atoms include 1,4-cyclohexylene group.
Examples of the aromatic ring structure in the aromatic hydrocarbon group having 6 to 12 carbon atoms include a phenyl ring, a naphthyl ring, and a biphenyl ring. The aromatic hydrocarbon group may have a side chain, and examples of the side chain are the same as in the case of the cyclic aliphatic hydrocarbon group. Specific examples of the aromatic hydrocarbon group having 6 to 12 carbon atoms include 1,2-phenylene group, 1,4-phenylene group, 4,4′-biphenylene group and the like.
Specific examples of the group formed by linking an aromatic hydrocarbon group and an aliphatic hydrocarbon group having a total carbon number of 7 to 14 include —CH ₂ —C ₆ H ₄ —, —CH ₂ CH ₂ —C _6. H ₄ -C ₆ H _4- and the like can be mentioned.

As A ¹ , a group in which a part of the atoms constituting the hydrocarbon group is substituted with a hetero atom may be used. The atom substituted by the hetero atom may be either the main chain or the side chain constituting A ^1, and may be either a carbon atom or a hydrogen atom. Further, the hetero atom means an atom other than a carbon atom and a hydrogen atom, for example, a halogen such as a fluorine atom, a chlorine atom, a bromine atom or an iodine atom; a nitrogen atom, an oxygen atom, a silicon atom, a phosphorus atom or a sulfur atom. Atoms belonging to typical elements such as;
Examples of the hydrocarbon group partially substituted with a hetero atom include a methylene difluoride group (—CF ₂ —), a tetrafluoroethylene group (—CF ₂ CF ₂ —), and —CH ₂ O—C _6. H ₄ —, —CH ₂ NH—C ₆ H ₄ — and the like can be mentioned.

A ¹ is a single bond or a methylene group, ethylene group, trimethylene group, propylene group, 1,4-cyclohexylene group, 1,2-phenylene group, 1,4-phenylene group, and 4,4′-. It is preferable to use a hydrocarbon group selected from the group consisting of a biphenylene group, and it is more preferable to use a single bond or a 1,4-phenylene group.

p, q and r each represents an integer of 0 or 1. However, when B ¹ is a single bond, p + q + r ≧ 1. That is, when the terminal substituent on the upper left of the general formula (1) is a t-butoxycarbonyl group, at least one of p, q and r is an integer of 1, and the other terminal substituent (t-butoxycarbonyl) Group or t-butoxycarbonyloxy group). The reason for this is that a polymer material containing only one t-butoxycarbonyl group as a terminal substituent in the structural unit of the general formula (1) can be used even when the temperature exceeds 100 ° C. when used in an all-solid battery. This is because decomposition hardly occurs (see Comparative Example 2 described later).
Note that A ² and B ² when p is 1 are as described above, but when p is 0, a carbon atom that is the main chain skeleton of the repeating unit has a hydrogen atom instead of A ^2. Join. The same applies to the relationship between q, A ³ and B ^{3 and} the relationship between r, A ⁴ and B ⁴ .

The “main repeating unit” in the present disclosure means a repeating unit that occupies a sufficiently high ratio for the polymer material to exert the effects of the present disclosure. More specifically, the “main repeating unit” refers to a ratio of the repeating unit of 80 mol% or more and 100 mol% or less, preferably 90 mol% or more and 100 mol% when the number of moles of the whole polymer material is 100 mol%. Hereinafter, it means that it is 95 mol% or more and 100 mol% or less, more preferably 100 mol%.
Therefore, as long as the object of the present disclosure can be achieved, the polymer material may contain another repeating unit different from the general formula (1). When the total number of moles of the polymer material is 100 mol%, the proportion of other repeating units is preferably 20 mol% or less, more preferably 10 mol% or less, and even more preferably 5 mol% or less. .

  The following general formula (1A) and general formula (1B) represent structural units suitable for having as main repeating units in the polymer material of the present disclosure.

In the general formula (1A), A ^1a , A ^2a , A ^3a and A ^4a are each independently a single bond, a methylene group (—CH ₂ —) or an ethylene group (—CH ₂ CH ₂ —). , Trimethylene group (—CH ₂ CH ₂ CH ₂ —), propylene group (—CH (CH ₃ ) CH ₂ —), 1,4-cyclohexylene group, 1,2-phenylene group, 1,4-phenylene group, And a hydrocarbon group selected from the group consisting of 4,4′-biphenylene groups.
p _a , q _a, and r _a represent an integer of 0 or 1, and p _a + q _a + r _a ≧ 1.
Specific examples of the polymer having the structural unit represented by the general formula (1A) include poly (di-tert-butyl fumarate) (A ^1a and A ^2a are single bonds, p _a = 1 _, q _a = r _a = 0) Etc.

In the general formula (1B), A ^1b , A ^2b , A ^3b and A ^4b are each independently a single bond, a methylene group (—CH ₂ —), an ethylene group (—CH ₂ CH ₂ —). , Trimethylene group (—CH ₂ CH ₂ CH ₂ —), propylene group (—CH (CH ₃ ) CH ₂ —), 1,4-cyclohexylene group, 1,2-phenylene group, 1,4-phenylene group, And a hydrocarbon group selected from the group consisting of 4,4′-biphenylene groups.
p _{b, q b} and _{r b} are each independently an integer of 0 or 1.
Specific examples of the polymer having the structural unit of the general formula (1B) include poly (4-t-butoxycarbonyloxystyrene) (A ^1b is a 1,4-phenylene group, p _b = q _b = r _b = 0. ) And the like.

The number average molecular weight Mn of the polymer material is preferably 5,000 or more and 200,000 or less, more preferably 10,000 or more and 150,000 or less, and further preferably 15,000 or more and 100,000. It is as follows. When the number average molecular weight Mn of the polymer material is less than 5,000, the polymer chain is too short, so that the function as a binder may not be exhibited. On the other hand, when the number average molecular weight Mn of the polymer material exceeds 200,000, the viscosity of the composition containing the polymer material may increase, or the polymer material may be difficult to dissolve in the solvent. This may cause difficulty in preparing battery materials.
As a method for measuring and calculating the number average molecular weight Mn of the polymer material, a known method can be adopted. For example, the method for measuring and calculating the number average molecular weight of a polymer described in JIS K7252-1-4 are used. be able to.

In the polymer material, the number of repeating main repeating units is preferably 25 or more and 1,000 or less, more preferably 50 or more and 750 or less, and further preferably 75 or more and 500 or less.
When the number of main repeating units is less than 25, the number of terminal substituents (t-butoxycarbonyl group or t-butoxycarbonyloxy group) in the polymer material becomes too small. There is a risk that the amount of gas generated will be reduced. On the other hand, when the number of repeating main repeating units exceeds 1,000, the viscosity of the composition containing the polymer material may increase, or the polymer material may become difficult to dissolve in the solvent. This may make it difficult to prepare battery materials.
As a method for measuring and calculating the number of repetitions of the polymer material, a known method can be adopted as a method for measuring and calculating the degree of polymer polymerization. For example, a polymer material obtained by using gel permeation chromatography or gel filtration chromatography. The degree of polymerization can be calculated from the average molecular weight.

The onset temperature of mass reduction in the TG curve of the polymer material obtained by differential thermal-thermogravimetric simultaneous analysis based on JISK 0129: 2005 is preferably 150 ° C. or higher and 220 ° C. or lower, more preferably 160 ° C. The temperature is 210 ° C. or lower, and more preferably 170 ° C. or higher and 200 ° C. or lower.
The differential thermal-thermogravimetric analysis (simultaneous thermogravimetry and differential thermal analysis: TG-DTA) is as defined in JISK 0129: 2005 3d) 1). The TG curve is as defined in 3s) of the same standard.
The onset temperature of mass decrease in the TG curve is the temperature at which decomposition of the polymer material begins, that is, the terminal substituent (at least one of t-butoxycarbonyl group and t-butoxycarbonyloxy group) decomposes. This is the temperature at which isobutene and carbon dioxide begin to be generated. If the starting temperature is less than 150 ° C., when the binder is used for an all-solid battery, the polymer material may start to decompose only when the temperature of the all-solid battery rises slightly, and the battery can be operated safely. Even in the temperature range, the battery reaction may stop. On the other hand, if the start temperature exceeds 220 ° C., when the binder is used for an all-solid battery, the polymer material may start to decompose at a stage where the all-solid battery becomes sufficiently hot. Regarding the method for determining the onset temperature of mass reduction, the descriptions of 2 (4) and 8 (2) and (3) of JISK 7120, which are related standards, can be referred to.
Note that there is a difference of approximately 50 ° C. or more between the start temperature (150 ° C. or more and 220 ° C. or less) and the limit value (for example, around 100 ° C.) of the battery surface temperature assumed in the present disclosure. This takes into account the difference in heat distribution across the battery. That is, in the present disclosure, when the surface temperature of the battery reaches 100 ° C., it is assumed that a portion of 150 ° C. or higher is already locally generated inside the battery. As the locally generated portion of 150 ° C. or higher, for example, a portion where the battery member is damaged due to overcharge, external short circuit, or the like can be considered. When the battery member is locally heated to 150 ° C. or higher, a chain exothermic reaction of the battery member may occur.

Formula mass reduction rate M _L of the polymeric material obtained by (A) is preferably not more than 99% more than 40%, more preferably not more than 99% to 42%, and more preferably 45 % To 99%.
Formula _{(A) M L = (m} 150 ℃ -m 220 ℃ / m 150 ℃) × 100
(In the above formula (A), _{M L} is a mass reduction rate of the polymer material _{(%), m 150 ℃} is JISK 0129: a differential thermal conforms to 2005 - of the polymer material obtained by thermogravimetric simultaneous analysis (The mass (mg) at 150 ° C. in the TG curve, and m _{220 ° C.} represents the mass (mg) at 220 ° C. in the TG curve.)
When the mass reduction rate M _L is less than 40%, the polymer material at a temperature region of 0.99 ° C. or higher 220 ° C. or less is not sufficiently decomposed, there is a possibility that the gas generation amount under high temperature conditions is reduced. On the other hand, in a polymer material having a main chain skeleton composed of a carbon-carbon bond as the main repeating unit as in the general formula (1), it is difficult to completely decompose this main chain skeleton at 220 ° C. the reduction rate M _L exceeds 99% is usually difficult to assume.
Note that the mass reduction rate _{M L} in the formula (A), 8 (2) and (3) of JISK 7120 and the disclosure of 9.2 can be referred to.

2. All-solid-state battery The all-solid-state battery of this indication has a positive electrode, a negative electrode, and the solid electrolyte which exists between a positive electrode and a negative electrode, and at least any one of a positive electrode, a negative electrode, and a solid electrolyte is the said all-solid-state battery. A binder is included.
The structure of the all solid state battery of the present disclosure is not particularly limited as long as the binder of the present disclosure is used as described above.

The all solid state battery of the present disclosure may have a structure using high temperature decomposition of the binder of the present disclosure.
For example, in the all-solid-state battery of the present disclosure, the battery member is deformed by a physical method when a small molecule gas (for example, isobutene, carbon dioxide, etc.) generated by the decomposition of the binder of the present disclosure diffuses in the battery. Or the battery member may be altered by a chemical method, and the battery reaction may be stopped.
The all-solid-state battery of the present disclosure further includes a sensor and a control circuit. When the small molecule gas generated by the decomposition of the binder of the present disclosure is detected by the sensor and the concentration of the small molecule gas exceeds a certain amount, The battery reaction may be stopped via a control circuit by a signal emitted from the sensor.
Note that these are merely examples of the battery structure, and the present disclosure is not limited to these examples.
In the present disclosure, the above-described structures in which the battery reaction stops due to the high-temperature decomposition of the binder are collectively referred to as “battery reaction stop structure”.

Hereinafter, an embodiment of the all-solid battery of the present disclosure will be described. This embodiment has a structure in which when a small molecule gas is generated, a current is interrupted by deforming a part of the battery member using a physical method, and as a result, the battery reaction is stopped.
FIG. 1 is a schematic plan view of the present embodiment. The all-solid-state battery 100 of this embodiment includes a laminate 10, an exterior body 20 that seals the laminate 10, and a flat negative electrode that has one end connected to the laminate 10 and the other end protruding outside the exterior body 20. The terminal 30 and the positive electrode terminal 40 are provided.

The laminate 10 is formed by laminating a sheet-like negative electrode (not shown), a sheet-like positive electrode (not shown), and a solid electrolyte (not shown) existing between the positive electrode and the negative electrode. The
As the positive electrode active material in the positive electrode, for example, a layered oxide (ternary active material) containing Li, Ni, Mn and Co can be used, and a specific example thereof is LiNi _1/3 Co _1/3 Mn _{1. /} is a 3 _{O 2.} The positive electrode active material may include a coating layer made of LiNbO ₃ or the like. In addition to the positive electrode active material, a conductive material such as VGCF or a solid electrolyte such as Li ₂ S—P ₂ S ₅ may be used for the positive electrode.
As the negative electrode active material in the negative electrode, for example, a carbon material or a silicon material can be used. Specific examples of the carbon material include spheroidized natural graphite and graphite. Specific examples of the silicon material include silicon crystals. And amorphous, alloys containing silicon, and composites containing silicon. In addition to the negative electrode active material, a conductive material such as VGCF or a solid electrolyte such as Li ₂ S—P ₂ S ₅ may be used for the negative electrode.
As the solid electrolyte between the positive electrode and the negative electrode, for example, a sulfide-based solid electrolyte, an oxide-based solid electrolyte, or the like can be used. Specific examples of the sulfide-based solid electrolyte include Li ₂ S—P ₂ S ₅ .

The binder of this indication should just be contained in at least any one of the positive electrode mentioned above, a negative electrode, and a solid electrolyte.
The binder content is not particularly limited. For example, when the binder is included in the positive electrode, the binder content may be 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the positive electrode active material. Is 0.3 parts by mass or more and 3.0 parts by mass or less, and a more preferable content ratio of the binder is 0.5 parts by mass or more and 2.5 parts by mass or less. If the content of the binder with respect to 100 parts by mass of the positive electrode active material is less than 0.1 parts by mass, the effects of the present disclosure may not be sufficiently enjoyed. On the other hand, when the content of the binder with respect to 100 parts by mass of the positive electrode active material exceeds 5.0 parts by mass, the content of other materials in the positive electrode is relatively reduced, and as a result, the battery performance may be deteriorated.
The numerical range of the content ratio of the binder is the same when the binder is included in the negative electrode and when the binder is included in the solid electrolyte. When the binder is included in the negative electrode, the content of the binder is based on 100 parts by mass of the negative electrode active material. Moreover, when a binder is contained in a solid electrolyte, the said content of a binder shall be with respect to 100 mass parts of solid electrolytes.

  A flexible laminate film is used for the exterior body 20. The laminate 10 is sandwiched between two laminate films, and the outer periphery is joined and sealed by heat welding. At this time, the negative electrode terminal 30 and the positive electrode terminal 40 are also joined to the exterior body 20. An adhesive may be used for bonding.

  The negative electrode terminal 30 includes a flat plate-like internal terminal 31 positioned inside the outer package 20, a flat plate-like external terminal 32 whose one end is positioned inside the outer package 20, and the other end projects outside the package 20. Consists of Normally, the internal terminal 31 and the external terminal 32 are in contact with each other, and a current flows between the internal terminal 31 and the external terminal 32. However, the peeling occurs when the internal pressure of the exterior body 20 becomes a predetermined pressure. Current is cut off. In the present embodiment, only the negative electrode terminal 30 includes the internal terminal 31 and the external terminal 32, but the positive electrode terminal 40 may include the internal terminal and the external terminal, or both the negative electrode terminal 30 and the positive electrode terminal 40. May have an internal terminal and an external terminal. From the viewpoint of maintaining the sealed state of the battery, it is desirable that the internal pressure of the exterior body 20 when the internal terminal and the external terminal are peeled is smaller than the pressure at which the exterior body 20 bursts.

FIG. 2 is a schematic cross-sectional view of the present embodiment, showing the AA cross section in FIG. The exterior body 20 and the negative electrode terminal 30 will be described in detail with reference to FIG.
As shown in FIG. 2, the first end 31 </ b> A on the laminated body 10 side of the internal terminal 31 is connected to the negative electrode (not shown) of the laminated body 10. The second end 31B opposite to the first end 31A is overlapped with the first end 32A of the external terminal 32 on the stacked body 10 side. At this time, the upper surface 31C of the internal terminal 31 and the lower surface 32D of the external terminal 32 are in contact with each other, and the internal terminal 31 and the external terminal 32 are electrically connected.
The portion l ₁ that overlap the internal terminal 31 and the external terminal 32, the length, in the case where a pressure that the internal pressure of the exterior body is predetermined, so that the internal terminal 31 and the external terminal 32 is peeled off Set to In the portion l ₁ , the internal terminal 31 and the external terminal 32 are merely in contact with each other and are not joined. A second end portion 32 </ b> B located on the side opposite to the first end portion 32 </ b> A of the external terminal 32 protrudes outside the exterior body 20. Devices (not shown) are connected to the second end 32B of the external terminal 32.

In the portion L where the external terminals 32 are present inside the exterior body 20, the upper surfaces of the external terminals 32 are all joined to the exterior body 20. In the portion ₁₁ , the lower surface of the internal terminal 31 is all joined to the exterior body 20. Further, in the portion l ₂ of the external terminal 32 is present inside the exterior body 20, and does not overlap the internal terminal 31 and the external terminal 32, the lower surface of the external terminal 32 are joined to all exterior body 20.

FIG. 3 is a schematic cross-sectional view showing a state where the internal terminal 31 and the external terminal 32 are peeled off due to the generation of the small molecule gas in the present embodiment.
Assume that the temperature of the all solid state battery of the present embodiment rises to around 100 ° C., and as a result, the binder of the present disclosure is decomposed and a small molecule gas is generated. Here, in the portion l ₁ that overlap the internal terminal 31 and the external terminal 32, whereas it is merely in contact to the internal terminal 31 and the external terminal 32, internal terminal 31 lower surface or the external terminal 32 upper surface Both are joined to the exterior body 20 respectively. Therefore, the generated gas enters the gap between the internal terminal 31 and the external terminal 32.

  When gas enters the gap between the internal terminal 31 and the external terminal 32, a force acts in a direction in which the internal terminal 31 and the external terminal 32 are peeled off due to the pressure of the gas. When the gas continues to be generated and the internal pressure rises to a predetermined pressure, the internal terminal 31 and the external terminal 32 are separated. A margin may be provided in the structure of the exterior body 20 so that the exterior body 20 can be expanded by the gas.

When the internal terminal 31 and the external terminal 32 are separated from each other, the connection between these terminals is cut off, so that the current is cut off. For this reason, a battery reaction stops and generation | occurrence | production of gas also stops. In the portion L where the external terminal 32 is present inside the exterior body 20, the bonding between the upper surface of the external terminal 32 and the exterior body 20 is maintained. Also, there external terminal 32 inside the exterior body 20, and also in part l ₂ of the internal terminal 31 and the external terminal 32 does not overlap, at least a portion joining the lower surface and the outer body 20 of the external terminal 32 is maintained Has been. Thereby, even when the internal terminal 31 and the external terminal 32 peel, the sealed state inside the exterior body 20 is maintained. Accordingly, the generated gas does not leak to the outside of the exterior body 20, the internal pressure of the exterior body 20 can be maintained at a predetermined pressure or more, and the peeled state between the internal terminal 31 and the external terminal 32 is maintained. be able to. As a result, it is possible to prevent the internal terminal 31 and the external terminal 32 from coming into contact with each other, causing current to flow and regenerating gas.

As described above, the all solid state battery of the present embodiment can stop the generation of gas by separating the internal terminal 31 and the external terminal 32 after the generation of the small molecule gas to cut off the current. Moreover, after the internal terminal 31 and the external terminal 32 peel, the internal pressure in the exterior body 20 is maintained, and the state where the internal terminal 31 and the external terminal 32 peel can be maintained.
Regarding the structure of the all-solid-state battery of the present disclosure, the structure described in JP-A-2005-44523 can also be referred to.

Hereinafter, an example of the manufacturing method of the all-solid-state battery of this indication is demonstrated.
First, the positive electrode material described above is mixed to prepare a positive electrode mixture. Similarly, a negative electrode mixture is prepared from the negative electrode material described above. These electrode mixtures are applied to a substrate to form an electrode active material layer. A solid electrolyte layer is formed on the surface of one electrode active material layer, and the other electrode active material layer is further placed on the solid electrolyte layer, thereby providing a single electrode comprising a positive electrode active material layer, a solid electrolyte layer, and a negative electrode active material layer. Manufacture batteries. Here, the binder of this indication should just be contained in at least any one among a positive electrode, a negative electrode, and a solid electrolyte.
Next, two or more unit cells are stacked to produce a stacked body. Each current collecting tab of the laminate is connected to the positive electrode terminal or the negative electrode terminal, and the obtained laminate is accommodated in the exterior body, whereby the all-solid battery of the present disclosure is completed. At this time, a battery reaction stop structure may be adopted for at least one of the positive electrode terminal and the negative electrode terminal. That is, for example, the electrode terminal may be composed of an internal terminal and an external terminal, and the battery contact may be stopped by disconnecting the electrical contact between the internal terminal and the external terminal due to high-temperature decomposition of the binder. Moreover, a battery reaction stop structure may be adopted in the solid electrolyte layer, or another battery reaction stop structure described in JP-A-2005-44523 may be adopted.
The above manufacturing method is merely an example, and the method of manufacturing the all-solid battery of the present disclosure is not limited to the above method.

  Hereinafter, the present disclosure will be described more specifically with reference to examples. However, the present disclosure is not limited to the examples.

[Example 1]
1. Production of Laminate Cell (1) Formation of Positive Electrode Active Material Layer A ternary active material (particle size: 1 to 10 μm) as a positive electrode active material, a crystalline sulfide solid electrolyte as a solid electrolyte, and a poly (di- TGCF was used as a conductive material for improving the electronic conductivity of a 5 mass% toluene solution of t-butyl fumarate). A paste was prepared by adding heptane to a mixture of these positive electrode materials and dispersing the positive electrode material in heptane using an ultrasonic homogenizer (manufactured by SMT, UH-50) as a dispersion mixer. The solid content of the paste is 50% by mass, and the mass ratio of the positive electrode active material to the solid electrolyte in the paste is positive electrode active material: solid electrolyte = 75 parts by mass: 25 parts by mass, and binder (poly (di-t-butyl fumarate) )) Content was 1.5 parts by mass with respect to 100 parts by mass of the positive electrode active material.
The prepared paste was applied onto an aluminum foil by a doctor blade method and dried to form a positive electrode active material layer.

  The number average molecular weight Mn of poly (di-t-butyl fumarate) used in Example 1 (the following formula (1a), hereinafter this compound may be referred to as polymer 1) is 19,300. The number of repetitions n in the following formula (1a) is 85.

(2) Formation of negative electrode active material layer Natural graphite as the negative electrode active material, crystalline sulfide solid electrolyte as the solid electrolyte, and 5% by mass toluene solution of poly (di-t-butyl fumarate) as the binder solution, respectively Using. A paste was prepared by adding heptane to a mixture of these negative electrode materials and dispersing the negative electrode material in heptane using an ultrasonic homogenizer (UH-50, manufactured by SMT) as a dispersion mixer. The solid content of the paste is 50% by mass. In the paste, the mass ratio of the negative electrode active material to the solid electrolyte is negative electrode active material: solid electrolyte = 58 parts by mass: 42 parts by mass, and the binder (poly (di-t-butyl fumarate) is used. )) Content was 1.1 parts by mass with respect to 100 parts by mass of the negative electrode active material.
The prepared paste was applied onto a copper foil by a doctor blade method and dried to prepare a negative electrode active material layer.

(3) Formation of solid electrolyte layer and production of unit cell A sulfide solid electrolyte was used as a solid electrolyte, and PVdF was used as a binder. Heptane was added to the mixture of these solid electrolyte layer materials, and a slurry was prepared by dispersing the solid electrolyte layer material in heptane using an ultrasonic homogenizer (manufactured by SMT, UH-50) as a dispersion mixer. The solid content of the slurry was 50% by mass, and the mass ratio between the solid electrolyte and the binder in the slurry was solid electrolyte: binder = 95% by mass: 5% by mass.
The prepared slurry was applied to the surface of the copper foil on which the negative electrode active material layer was formed, and the solvent was evaporated and dried to form a solid electrolyte layer. A unit cell was fabricated by further stacking a positive electrode active material layer on an aluminum foil on the solid electrolyte layer.

(4) Production of Laminate Cell 20 unit cells thus produced were stacked to produce a laminate. Each current collecting tab of the laminate was ultrasonically welded to the positive terminal or the negative terminal. The obtained laminate was vacuum-sealed in a laminate to produce an all-solid battery (laminate cell). At this time, a battery reaction stop structure was adopted for the negative electrode terminal. That is, the negative electrode terminal is composed of an internal terminal and an external terminal as shown in FIGS. 1 and 2, and the periphery of the negative electrode terminal has a structure as shown in FIGS.

[Example 2]
In Example 1, “(1) Formation of positive electrode active material layer” and “(2) Formation of negative electrode active material layer”, instead of a 5 mass% toluene solution of poly (di-t-butyl fumarate), poly ( An all-solid-state battery (laminate cell) (Example 2) was produced in the same manner as in Example 1 except that the same mass of 5 mass% toluene solutions of 4-t-butoxycarbonyloxystyrene) was used.
The number average molecular weight Mn of poly (4-t-butoxycarbonyloxystyrene) used in Example 2 (the following formula (1b), hereinafter this compound may be referred to as polymer 2) is 41,100. . The number of repetitions n in the following formula (1b) is 187.

[Comparative Example 1]
In Example 1, “(1) Formation of positive electrode active material layer” and “(2) Formation of negative electrode active material layer”, instead of a 5 mass% toluene solution of poly (di-t-butyl fumarate), polyvinylidene An all-solid-state battery (laminate cell) (Comparative Example 1) was prepared in the same manner as in Example 1 except that the same mass was used for each 5 mass% toluene solution of fluoride (PVdF).
In addition, the number average molecular weight Mn of PVdF (following Formula (2)) used for the comparative example 1 is 100,000. The number of repetitions n in the following formula (2) is 1,560.

[Comparative Example 2]
In Example 1, “(1) Formation of positive electrode active material layer” and “(2) Formation of negative electrode active material layer”, instead of a 5 mass% toluene solution of poly (di-t-butyl fumarate), poly ( An all-solid battery (laminate cell) (Comparative Example 2) was prepared in the same manner as in Example 1 except that the same mass of 5% by mass toluene solutions of (t-butyl-4-vinylbenzoate) was used.
The number average molecular weight Mn of poly (t-butyl-4-vinylbenzoate) used in Comparative Example 2 (the following formula (3), hereinafter this compound may be referred to as polymer 3) is 54,000. is there. The number of repetitions n in the following formula (3) is 265.

[Comparative Example 3]
In Example 1, “(1) Formation of positive electrode active material layer” and “(2) Formation of negative electrode active material layer”, instead of a 5 mass% toluene solution of poly (di-t-butyl fumarate), poly ( All solid battery (laminate cell) (Comparative Example) as in Example 1 except that the same mass of 5 mass% toluene solution of 7,8-dicyano-7,8-dibutoxycarbonyl-p-quinodimethane) was used. 3) was produced.
The number of poly (7,8-dicyano-7,8-dibutoxycarbonyl-p-quinodimethane) used in Comparative Example 3 (the following formula (4), hereinafter this compound may be referred to as polymer 4). The average molecular weight Mn is 420,000. The number of repetitions n in the following formula (4) is 1,190.

2. TG-DTA
The differential thermal-thermogravimetric analysis (TG-DTA) was performed on the polymers 1 to 4, and the onset temperature of mass reduction was examined. TG-DTA was implemented based on JISK 0129: 2005. Moreover, it was calculated from TG curve obtained by TG-DTA, the mass reduction rate _{M L} of each polymer on the basis of the following formula (A). The onset temperature of mass reduction and the mass reduction rate are shown in Table 1 below.
Formula _{(A) M L = (m} 150 ℃ -m 220 ℃ / m 150 ℃) × 100
(In the above formula (A), the mass reduction rate of _{M L} polymer material _{(%), m 150 ℃} is JISK 0129: a differential thermal conforming to 2005 - TG curve of a polymer material obtained by thermogravimetric simultaneous analysis The mass (mg) at 150 ° C. in m, and m _{220 ° C.} represents the mass (mg) at _{220 ° C.} in the TG curve.

Thermogravimetry and mass spectrometry (TG / MS) was performed in parallel with TG-DTA, and for polymers 1 to 3, the onset of mass reduction (ie, the point of time of 195 ° C. per polymer 1) It was confirmed that the gas generated at 187 ° C. for polymer 2 and 240 ° C. for polymer 3) was isobutene (CH ₂ ═C (CH ₃ ) ₂ ).

3. Overcharge test After charging all solid state batteries of Example 1-Example 2 and Comparative Example 1-Comparative Example 3 to 4V, they were placed in a thermostat at 80 ° C., and the temperature was adjusted by a thermocouple attached to the surface of the battery. While measuring, the battery was overcharged with a current amount of 2C. Overcharging was performed until the battery reaction stop structure was activated and the current was cut off, and the maximum temperature reached by the cell immediately before the current was cut off was measured.
The results of the overcharge test are shown in Table 1 below. In Comparative Example 1, since the current was not interrupted up to 120 ° C, the test was terminated at 120 ° C.

  Table 1 below is a table summarizing the presence or absence of current interruption in the all-solid-state battery and the maximum temperature reached by the cell immediately before the current interruption, along with the physical properties of the polymer material and the measurement results. In Table 1 below, “250 <” means that the onset temperature of mass reduction exceeds 250 ° C.

4). Discussion Hereinafter, the experimental results of this example will be discussed with reference to Table 1 and FIG.
First, from Table 1, the all-solid battery of Comparative Example 1 did not block current even when the cell surface temperature reached 120 ° C. The reason for this is considered that PVdF in the all solid state battery was not decomposed even at 220 ° C., and no PVdF-derived gas was generated, and as a result, the temperature of the all solid state battery continued to rise.

As shown in Table 1, for the all solid state battery of Comparative Example 3, the current was cut off when the cell surface temperature reached 118 ° C. Even if the current stops after the surface temperature of the battery reaches 100 ° C., the deterioration of the battery member proceeds rapidly at a high temperature of 100 ° C. or higher, and the chain of battery members well above 100 ° C. inside the battery. Since the exothermic reaction has begun, the current interruption is too slow. The reason why the current is interrupted in this way is considered to be because the polymer 4 is hardly decomposed.
FIG. 4 supports the above reason. FIG. 4 is a graph showing the respective mass reduction rates of Polymer 1 to Polymer 4 in an overlapping manner. FIG. 4 is a graph in which the vertical axis represents mass reduction rate (%) and the horizontal axis represents temperature (° C.).
As can be seen from FIG. 4, the polymer 4 starts to decrease in mass from 250 ° C., gradually decomposes as the temperature rises, and then decomposes to about half of the initial mass at 400 ° C. Thus, the reason why the decomposition proceeds slowly at a sufficiently high temperature is that the repeating unit of the polymer 4 contains a substituent that is relatively difficult to decompose such as an n-butylcarbonyl group or a cyano group, and t- This is presumably because it does not contain a substituent that is easily decomposed even under relatively low temperature conditions such as a butylcarbonyl group and a t-butylcarbonyloxy group.

Next, from Table 1, for the all-solid-state battery of Comparative Example 2, the current was interrupted when the cell surface temperature reached 113 ° C. In Comparative Example 2, as in Comparative Example 3, the current interruption is too slow. The reason why the current interruption is slow is considered to be because the polymer 3 is hardly decomposed.
FIG. 4 supports the above reason. As can be seen from FIG. 4, the polymer 3 starts to rapidly decrease in mass from 240 ° C., and once reaches a plateau at 250 ° C., a second rapid mass decrease starts from 450 ° C. Polymer 3 eventually progresses to nearly 80% at 500 ° C. Here, from the result of the TG / MS, it is presumed that the mass decrease at 240 ° C. is derived from the elimination and decomposition of the t-butylcarbonyl group. Thus, the reason why the mass decrease of the polymer 3 starts at a high temperature of 240 ° C. is because the repeating unit of the polymer 3 contains only one t-butylcarbonyl group, and the density of the side chain that causes the decomposition reaction is small. This is thought to be because the chain reaction during decomposition is suppressed.

On the other hand, from Table 1, in the all solid state batteries of Example 1 and Example 2, the current was interrupted when the cell surface temperature reached 98 ° C or 90 ° C. The reason why the current is interrupted quickly in this way is considered to be because both polymers 1 and 2 rapidly decompose at a desired temperature.
FIG. 4 supports the above reason. As can be seen from FIG. 4, the mass of polymer 1 sharply decreases by more than half at 195 ° C., and then reaches the second mass decrease at 300 ° C. across the flat region. Polymer 1 finally undergoes degradation to near 90% at 500 ° C. From the above TG / MS results, it is presumed that the decrease in mass at 195 ° C. originates from elimination and decomposition of the t-butylcarbonyl group. On the other hand, as can be seen from FIG. 4, the mass of polymer 2 sharply decreases to almost half at 187 ° C., and then reaches the second mass decrease at 350 ° C. across the flat region. Polymer 2 decomposes almost completely before finally reaching 500 ° C. From the above TG / MS results, it is estimated that the mass decrease at 187 ° C. is elimination and decomposition of the t-butylcarbonyloxy group.
As described above, the reason why the mass reduction of the polymer 1 starts at a relatively low temperature of 195 ° C. is that the repeating unit of the polymer 1 contains two t-butylcarbonyl groups, and the density of the side chain that causes the decomposition reaction is large. Therefore, it is considered that a chain reaction occurs at the time of decomposition.
The reason why the mass decrease of the polymer 2 starts at a relatively low temperature of 187 ° C. is considered that the repeating unit of the polymer 2 contains a t-butylcarbonyloxy group that is easily decomposed. Note that, unlike the polymer 3, the polymer 2 contains a t-butylcarbonyloxy group that is more easily removed and decomposed than the t-butylcarbonyl group, and therefore has a mass at a relatively low temperature regardless of the number of terminal substituents. The decline is expected to start.

As described above, by using the binder of the present disclosure for an all-solid battery, even when the battery temperature rises during overcharge, the pressure in the battery rises due to the gas generated from the polymer in the binder. Was confirmed to operate normally. Moreover, it was also confirmed that the temperature increase of the all-solid battery can be suppressed as a result of the overcharge current being cut off at an appropriate temperature by the operation of the battery reaction stop structure. Therefore, it can be seen that the binder of the present disclosure is superior to the conventional binder because it can suppress the heat generation of the electrode active material during overcharge when used in an all-solid battery.
When Example 1 and Example 2 are compared, the difference between the onset temperature of mass reduction (Example 1: 195 ° C, Example 2: 187 ° C) and the maximum cell temperature (Example 1: 98 ° C, implementation) The difference in Example 2: 90 ° C is 8 ° C. Moreover, it can be said from the results of all the batteries in Table 1 that the lower the starting temperature of mass reduction, the lower the maximum temperature reached by the cell. Therefore, it is presumed that the temperature rise of the battery can be suppressed more quickly as the polymer that decomposes at a lower temperature is used as a binder without impairing the normal battery reaction.

DESCRIPTION OF SYMBOLS 10 Laminate 20 Exterior body 30 Negative electrode terminal 31 Internal terminal 31A First end 31B of internal terminal 31 Second end 31C of internal terminal 31 Upper surface 32 of internal terminal 31 External terminal 32A First end 32B of external terminal 32 External Second end 32D of terminal 32 Lower surface 40 of external terminal 32 Positive electrode terminal 100 All solid state battery 11 of this embodiment _{1 A} portion l ₂ where internal terminal 31 and external terminal 32 overlap ₂ External terminal 32 is present inside exterior body 20. And the part L in which the internal terminal 31 and the external terminal 32 do not overlap L The part in which the external terminal 32 exists in the exterior body 20

Claims (8)

An all-solid-state battery binder comprising a polymer material having a structural unit represented by the following general formula (1) as a main repeating unit.
(In the general formula (1), A ¹ , A ² , A ³ and A ⁴ are independently of each other,
Single bond, or
A linear aliphatic hydrocarbon group having 1 to 8 carbon atoms,
A branched C3-C8 acyclic aliphatic hydrocarbon group,
A C3-C8 cyclic aliphatic hydrocarbon group which may have a side chain,
An aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a side chain, a group formed by connecting an aromatic hydrocarbon group and an aliphatic hydrocarbon group having 7 to 14 carbon atoms in total, and ,
A group selected from the group consisting of groups in which some of the atoms constituting these hydrocarbon groups are substituted with heteroatoms is shown.
B ¹ , B ² , B ³ and B ⁴ each independently represent a single bond or an oxygen atom.
p, q and r each represents an integer of 0 or 1. However, when B ¹ is a single bond, p + q + r ≧ 1. )   The binder for all-solid-state batteries according to claim 1, wherein the polymer material has a number average molecular weight Mn of 5,000 or more and 200,000 or less.   The binder for all-solid-state batteries according to claim 1 or 2, wherein in the polymer material, the number of repetitions of the main repeating unit is 25 or more and 1,000 or less.   The start temperature of the mass reduction | decrease in the TG curve of the said polymeric material obtained by the differential thermal-thermogravimetric simultaneous analysis based on JISK 0129: 2005 is 150 to 220 degreeC, The any one of Claims 1 thru | or 3 The binder for all-solid-state batteries as described in a term. Formula (A) mass decrease rate M _L of the polymeric material as determined by is 99% or less than 40% total solids battery binder according to any one of claims 1 to 4.
Formula _{(A) M L = (m} 150 ℃ -m 220 ℃ / m 150 ℃) × 100
(In the above formula (A), _{M L} is a mass reduction rate of the polymer material _{(%), m 150 ℃} is JISK 0129: a differential thermal conforms to 2005 - of the polymer material obtained by thermogravimetric simultaneous analysis (The mass (mg) at 150 ° C. in the TG curve, and m _{220 ° C.} represents the mass (mg) at 220 ° C. in the TG curve.) The binder for all-solid-state batteries as described in any one of Claims 1 thru | or 5 in which the said polymeric material has a structural unit shown by the following general formula (1A) as a main repeating unit.
(In the above general formula (1A), A ^1a , A ^2a , A ^3a and A ^4a are independently of each other,
Single bond, or
Methylene group (—CH ₂ —), ethylene group (—CH ₂ CH ₂ —), trimethylene group (—CH ₂ CH ₂ CH ₂ —), propylene group (—CH (CH ₃ ) CH ₂ —), 1, 4 -A hydrocarbon group selected from the group consisting of a cyclohexylene group, a 1,2-phenylene group, a 1,4-phenylene group, and a 4,4'-biphenylene group.
p _a , q _a, and r _a represent an integer of 0 or 1, and p _a + q _a + r _a ≧ 1. ) The binder for an all-solid-state battery according to any one of claims 1 to 5, wherein the polymer material has a structural unit represented by the following general formula (1B) as a main repeating unit.
(In the above general formula (1B), A ^1b , A ^2b , A ^3b and A ^4b are independent of each other,
Single bond, or
Methylene group (—CH ₂ —), ethylene group (—CH ₂ CH ₂ —), trimethylene group (—CH ₂ CH ₂ CH ₂ —), propylene group (—CH (CH ₃ ) CH ₂ —), 1, 4 -A hydrocarbon group selected from the group consisting of a cyclohexylene group, a 1,2-phenylene group, a 1,4-phenylene group, and a 4,4'-biphenylene group.
p _{b, q b} and _{r b} are each independently an integer of 0 or 1. ) In an all-solid battery having a positive electrode, a negative electrode, and a solid electrolyte present between the positive electrode and the negative electrode,
8. An all-solid battery, wherein at least one of a positive electrode, a negative electrode, and a solid electrolyte includes the all-solid battery binder according to any one of claims 1 to 7.