JPH01230447A - Production of semi-solid electrolyte - Google Patents

Abstract

PURPOSE:To obtain a stable semi-solid electrolyte having high ionic conductivity and small temperature dependence, by adding a specific ion conductivity inducing material to an alkoxide of silicon and polymerizing by a hydrolyzing reaction. CONSTITUTION:(A) A water-containing metal oxide expressed by the formula (e.g., ZrO2.nH2O) having ion conductivity at least 10<-6>S.cm<-1> at 25 deg.C, (B) an inorganic or organic salt of metal in the component A dissolved in a solvent miscible with alkoxide of silicon, (C) an ion conductive inorganic compound (e.g., molybdophosphoric acid) dissolved in a solvent miscible with alkoxide of silicon, (D) an alkoxide of an element other than silicon and (E) one or more kinds of ion conductivity inducing material selected from solution of inorganic acid or organic acid, are prepared. Then the material is added to alkoxide of silicon and polymerized by a hydrolyzing reaction to afford the aimed semi- solid electrolyte.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a semi-solid electrolyte, and in particular to a method for producing a semi-solid electrolyte.
The present invention relates to a method of producing a highly ionic conductive semi-solid material by achieving a semi-solid state using a gel method.

[Background Art] Currently, with the trend toward solid-state electronic devices, interest in solid electrolytes is increasing. That is, liquid electrolytes have problems such as damage to the main body due to liquid leakage when they are made into devices, and the risk of being dangerous as a deleterious substance, so it is desired to solidify the electrolyte.

Solid electrolytes are expected to be used in a wide range of fields, including ion sensors, fuel cells, capacitors, solid batteries, display materials, and light control glass. In particular, the superionic conductive glass discovered by Kunze has attracted even more attention in recent years (D. Kunze, “Fast
Ton transport in 5 solid
s”.

Ed, W. van Gaol, Nort.
h 1rolland publ, 8mste
r-dam, 1973. i p. 405).

Regarding the ionic conductivity of solid electrolytes at room temperature, it is known that silver ion systems range from 10" to 10-'S-c m-' (RbAg4Is, etc.), which is at the level of night-body electrolytes. However, there are problems such as the amount of energy that can be extracted per vehicle is small, the decomposition voltage is low, and the cost of raw materials is high. Lithium is attracting attention as a material that does not have these problems, but lithium nitride, which exhibits 10-30-3S-', has extremely poor stability against humidity and a low decomposition voltage of 0.44μ. There is. From the point of view of ionic conductivity alone,
Molybdophosphoric acid (H3Mo
et t,.

17.1979). However, in the future, there will be a demand for the development of products that not only have high ionic conductivity but also have various characteristics such as decomposition voltage, durability, temperature characteristics, and flexibility.For example, in the development of fuel cells, etc. These conditions are listed as conditions for an ideal solid electrolyte (
Moonlight Separate Research and Development Results Report "Fuel Cell Power Generation Technology" Research and Development of Solid Electrolyte Fuel Cells "Research on High Performance Battery Materials" (National Institute of Industrial Science and Technology University Examination, 1987, p. 7).

■ High ionic conductivity (e.g. about Is-cm-')
.

■ Low electronic conductivity (for example, 1O-8S cm-'
below).

■ Temperature dependence of ionic conductivity is small (ie, activation energy is small).

■ High decomposition voltage (for example, 3 to 4 V).

■It has excellent stability and does not react with electrodes, EC membranes, etc.

■ Wide stable temperature range.

■ Specific gravity is small.

On the other hand, current solid electrolytes basically lack flexibility and have the disadvantage of poor workability. For this purpose, many attempts have been made to combine ionic conductors and organic substances. For example, in Japanese Patent Application Laid-Open No. 53-49234, an acrylic polymer is blended with an ionic conductor and molded after drying to give flexibility to the solid electrolyte. In JP-A-57-40230, a highly viscous substance is mixed into a solid electrolyte to give it plasticity. Further, in JP-A-59-181381, a paste of a hydrous metal oxide and an organic substance is prepared. Furthermore, a method has also been proposed in which an alkali metal salt and polyvinyl butyral resin are mixed with a high boiling point/low melting point solvent.

[Problem to be solved by the invention] However, the conventional method described above has excellent workability, excellent temperature characteristics, and high ionic conductivity at a practical level, which satisfies the requirements of (1) to (3) above. No one has been found with this. Therefore, there is a strong desire for an excellent electrolyte that can fully satisfy these properties.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a semi-solid electrolyte that has high ionic conductivity and is also excellent in temperature characteristics, processability, and other characteristics. .

[Means for Solving the Problems] The method for producing a semi-solid electrolyte of the present invention includes silicon alkoxide having the following ionic conductivity of 10-6S-cm-' or more at 25°C. Hydrous metal oxide Mx Oy -n H20 represented by the following general formula (where M=Zr, Sn, V, Sb, Th.

Cr, In, Ga, Ce, Nb, Ta, Y.

Ti) ■ The inorganic salt or organic salt of metal M in ■ above,
A solution of an ionically conductive inorganic compound in a solvent that is compatible with a silicon alkoxide.A alkoxide of an element other than silicon.A solution selected from inorganic acids or organic acids. The method is characterized in that after adding at least one substance that causes ionic conductivity, the alkoxide is polymerized by a hydrolysis reaction.

In other words, the inventors of the present invention have conducted intensive studies to find an electrolyte with excellent various properties, and as a result, they have found an electrolyte that chemically maintains an ionic conductor in a state close to a liquid state, but physically maintains it in a solid state. More specifically, an elastic polymer (hereinafter referred to as The present inventors have discovered that various conventional problems can be solved by a method of simultaneously embedding an ion conductor and a solvent, which is an ion conduction group, in a matrix (sometimes referred to as a "matrix").

In this case, is this matrix part insulating?
A similar example is the ionic conductor RbCu41 +, y5
It has been proven that even if C113,25 powder is mixed into an insulating polymer (rubber), there is almost no effect on ionic conductivity if the amount of ionic conductor exceeds a certain amount relative to the insulating polymer. (Nikkei New Material No. 37 (1)
987) p. 21).

In addition, in the gelation of an alkoxide, the viscosity increases numerically as the molecular weight increases. In this case, during the curing process under open or closed conditions, from one that flows according to the shape of the container, to one that does not fall in the direction of gravity even if the container is reversed, and has considerable deformability and elasticity,
Completely solidifies. The present invention utilizes the intermediate state from a fluid state to a completely solidified state during this curing process.

The present invention will be explained in detail below.

In the present invention, first, at least one substance that causes ionic conductivity selected from the above (1) to (4) (hereinafter sometimes referred to as "ion conductor source") is added to silicon alkoxide.

The alkoxide is -formula%formula%) (However, A is an alkoxide-forming element, and R is a substituent such as an alkyl group, which may contain a side chain or a double bond or be polyfunctional. ), in which A is silicon, R is generally known to be an alkyl group such as methyl, ethyl, propyl, butyl. These silicon alkoxides form siloxane bonds while producing alcohol through hydrolysis, so the boiling point and freezing point of the alcohol produced are
This will influence the properties of the semi-solid electrolyte obtained.

In the present invention, when considering viscosity, hydrophobicity, solubility, boiling point, etc., the alkyl group for R is preferably one that produces a high molecular weight, high boiling point alcohol such as propyl or butyl. In addition, in terms of the molecular weight of the silicate component,
, there is no problem in using the oligomer directly, but if you want to speed up the polymerization time, reduce the amount of liquid produced by hydrolysis, or mix it with other alkoxides with different hydrolysis rates, you may need to add some amount in advance. Polymerized products can also be used. In this case, the degree of polymerization is generally increased by heating or by adding water, acid, or alkali as a catalyst. In addition, when mixing two or more types of alkoxides, a common solvent can also be used.

Next, an ion conductor source added to such a silicon alkoxide will be described below.

(2) Hydrous metal oxide MXO,-nH20, which exhibits ionic conductivity of 10-6 S.cm-cm-' or higher at 25°C and is represented by the following formula (where M=Zr, Sn, V, Sb, Th.

Cr, In, Ga, Ce, Nb, Ta, Y.

Ti) Hydrous metal oxides having such ionic conductivity include ZrO2・nH2O, 5n02・nH2o, V2
05・nH2O, 5b205 ・nH2o, Th02・
nH2o, I n(OH)3 ・nH2O, Cr (O
H)s ・nH2O, Ga20s ・nH2o, Ce
O2・nH2O, Nb2O5・nH2O, Ta205・
Studies have been conducted on nH2o, Y203・nH2o, TiO2・nH20, etc. (However, the highest value is Ta20a・3.
0298 of 92H20=3×10-'S-cm-' (Solid 5tate1onics, 24
(1987) 147) ).

If such a hydrous metal oxide with ionic conductivity is directly mixed into silicon alkoxide and hydrolyzed,
The ionic conductor is uniformly dispersed in the matrix, and the water, solvent, or ionic conductor necessary for ionic conduction (in this case, protons) coexists.

■ Inorganic salts or organic salts of metal M listed in ■ above,
Dissolved in a solvent that is compatible with silicon alkoxide A more uniform dispersion can be achieved by adding the hydrated metal oxide mentioned above in a liquid form and then hydrolyzing it, rather than adding it as a solid. can. That is, as a starting material, an inorganic salt or an organic salt of the metal is dissolved in a soluble solvent, and any mismixing in the silicon alkoxide is caused by the synthesis of a hydrous metal oxide during the process of matrix formation by subsequent hydrolysis. This can be done almost at the same time, resulting in better results.

(2) An ion-conductive inorganic compound dissolved in a solvent that is compatible with silicon alkoxide.Heteropolyacids are ion-conductive inorganic compounds that have been reported to have very high proton conductivity. Typical examples include molybdophosphoric acid, which has the highest proton conductivity at room temperature of σ-0.2S-cm-', and tungstophosphoric acid.

These ionically conductive inorganic compounds dissolve well in solvents that are compatible with silicon alkoxides, such as alcohols and polyols, so by first dissolving them in these solvents and then adding them to silicon alkoxides,
Uniform dispersion is obtained.

By the way, among the above-mentioned ion-conductive inorganic compounds, molybdophosphoric acid, which exhibits high ionic conductivity, is yellow in color, and gradually changes to green when alcohol is added. For this reason,
If you need to synthesize a transparent proton conductor,
A colorless one such as tungstophosphoric acid may be selected, and in this case, it is desirable to change the blending ratio as appropriate. It is also known that the proton moiety of this heteropolyacid is replaced with other alkali metal ions, such as lithium, sodium, potassium, etc. In particular, lithium molybdophosphate has high ionic conductivity, Moreover, the stability is also good. Furthermore, it is also possible to change the type of tetraelectric ion by appropriately selecting the cation.

(2) Alkoxide of an element other than silicon A semi-solid electrolyte can be synthesized by adding another alkoxide of an element other than silicon to an alkoxide of silicon. In this case, the alkoxide is triethyl phosphate (o=p (oEt)3),
If a material that generates acid during the hydrolysis reaction is selected, a floton conductor can be obtained. In addition, when mixing two or more types of alkoxides in this way, if the hydrolysis rates of the alkoxides used are significantly different, water and a catalyst (acid, etc.) may be added to the slower alkoxide in advance and refluxed to some extent. By mixing after hydrolysis, uniformity can be improved. Furthermore, in cases where there is no compatibility due to different bonded groups, or where there is no compatibility due to different elemental properties, two or more types of solvents may be used as appropriate. The same is true when an alkoxide is a solid and requires a solvent.

■ Inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, propionic acid, toluene sulfone, Organic acids such as acids can be used. These can be adjusted to a predetermined ionic conductivity by changing the concentration added to the silicon alkoxide.

By the way, in the present invention, it is desirable that the solvent used to dissolve or mix the ion conductor sources described in (1) to (4) above has the same component as the alcohol produced by the decomposition of silicon alkoxide. In addition, it is desirable that it has a high boiling point, a low melting point, is colorless, has an appropriate viscosity and weather resistance, is harmless, and has appropriate polarity if necessary. -Numerically, methanol,
Alcohols such as ethanol, propatool, butanol, methylcellosolve, polyfunctional alcohols (polyols) such as ethylene glycol, propanediol, butanediol, glycerin, polyethers, N,N-dimethylformamide, dimethylacetamide, dimethylsulfate, etc. Amide and nitrile solvents such as fluoride and acetonitrile, methyl ethyl ketone, furfural, propylene carbonate, previolactone and dioxane, THF
Or is it desirable to select from organic solvents such as various polymerizable monomers such as methacrylic acid and acrylic acid?
It is not limited to these.

In the present invention, silicon alkoxy F and the above
The above-mentioned solvent, water, polymerization agent, and liquid electrolyte can be further added and mixed as necessary to the mixed system with the ionic conductor source, and the mixing ratio thereof can achieve the purpose of the present invention. It can be determined arbitrarily within the range. There is a certain composition range in which the ionic conductivity does not decrease, but other parameters (check items), such as transparency, non-separability, and stability, are also important factors in determining the mixing ratio. Therefore, the decision shall be made as appropriate depending on the purpose. In addition, handling (
In terms of workability, it is desirable to be able to store the mixture in a near-liquid state and pour it into a device, so it is desirable that the viscosity of the raw mixture is low. However, if a large amount of solvent is used, subsequent gelation is significantly hindered, sometimes gelation does not occur, and solvent leaching after sealing is likely to occur. On the other hand, if it is in a small amount, when silicon alkoxide is added later, precipitation may occur due to solubility problems, causing non-uniform dispersion. For this reason, it is preferable to appropriately determine the amount of solvent to be used depending on the type of the mixed system.

Hydrolysis of the silicon alkoxide in the mixed system containing the silicon alkoxide and the ionic conductor source thus obtained can be caused by the addition of water, by moisture introduced during the synthesis process, by the addition of solvents or other compounds, etc. Possible causes include crystal water and water contained therein, but are not particularly limited to these. In addition, in order to promote hydrolysis, acids or alkalis are usually added or heated, or if it is possible to achieve the purpose of the present invention, such acids or alkalis are added or heated. The presence or absence of this, its degree, etc. are not particularly limited and can be set as appropriate.

In the present invention, the semi-solid material produced by polymerization through the hydrolysis reaction has complex interactions (coordination bonds) such as ionic conductors, silicon oxide, solvents, and water that cannot be expressed simply by composition. It is an aggregate of compounds, mixtures, and reaction intermediates that have interactions such as , ionic bonds, hydrogen bonds, and interactions due to polarization, and even water has different forms of existence and roles depending on its location. In order to stably preserve these groups of substances in a non-equilibrium state, it is important to store them in a sealed space. As mentioned above, the viscosity of the original mixed solution increases during standing or storage in a closed container, and even if the container is tilted, it will no longer self-flow. Therefore, in order to produce a stable semi-solid electrolyte that exhibits the necessary ionic conductivity, it is important to seal and seal the electrolyte at some point in the process of reaching the semi-solid state.

The conductive ionic species of the semi-solid electrolyte produced by the present invention may be numerically hydrogen (protons), cations such as alkali metals such as lithium and sodium, and anions such as fluorine and oxygen. . Examples of the ionic conductor to be dispersed include oxides, nitrides, halides, etc. In order to achieve a high degree of dispersion in the alkoxide matrix, the ionic conductor source may be one that is soluble in alkoxide or alkoxide. It is more desirable to add it in the form of a metal salt or complex that is soluble in a compatible solvent.

Note that the proton conductor differs from other systems in some respects. For example, in molybdophosphoric acid, there is a positive correlation between the amount of crystallization water and proton conductivity, so it is said that hydrogen bonding between water hydrogens seems to play an important role. In addition, in the case of yttrium oxide, there is a report that a small amount of water vapor is taken in to generate protons between the crystal lattices, and electrical conductivity occurs due to these protons (JAm
, Ceram, Soc, 69.780°1986).

According to many of these reports, water must be contained in the solid electrolyte.

Regarding this point, whether the proton conductor contains water in the starting material itself (such as heteropolyacid) or does not contain water (such as phosphorus alkoxide or antimony salt), silicon such as tetraethyl silicate is then used. The amount of water that is added to hydrolyze the alkoxide or that inevitably comes in from the atmosphere can be sufficient to compensate.

On the other hand, ionic conductors other than protons, such as Li', N
There are reports that water actually plays an important role in alkali metals such as a'', but it is not necessary to add water in order to exhibit ionic conductivity. For example, in lithium ion conductors, LiBr, LiF, LiCu, LiI, LiAs are used as lithium salts under non-aqueous conditions.
F6 (Li F-AsF5), LiAuCf14, L
iBF4. LiCIO4 can be used, or a salt containing such a mobile ionic species can be dissolved in a soluble solvent (such as propylene carbonate) and kept dispersed in the matrix.

[Function] In the present invention, the ionically conductive substance is provided in a semi-solid state. The semi-solid electrolyte of the present invention is divided into a portion having ionic conductivity and a matrix portion supporting the ionic conductivity and holding the solvent, depending on the type of the ionic conductor.

The matrix portion is a flexible gel-like material produced as a result of polymerization through hydrolysis of silicon alkoxide, and does not itself have ionic conductivity. Normally, it has the role of holding the ionic conductor part in an amorphous state and the role of holding the solvent (including the crystal water contained in advance to the water and organic solvent added later), and the ionic conductor part It is also the place where contact with the solvent is achieved. However, if mixing or bonding with the ion conductive substance at the molecular level is achieved, the matrix portion may play a more active role in the ion conduction phenomenon.

Regarding proton conductors, mixed or dissolved ionic conductors, silanol groups (SiOH) generated during the polymerization process of this alkoxide, oxygen of siloxane bonds, unreacted alkoxy groups, water (crystal water, added In the matrix, a wide variety of bonds (mostly hydrogen bonds) interact with each other, such as the OH groups of dissolved water or water that inevitably enters, dissolved hydrogen ions, and polarized moieties and functional groups in the added organic solvent. I can say that it is.

The semi-solid electrolyte synthesized according to the present invention can be made into a transparent material, and has various characteristics such as high ionic conductivity close to that of a liquid, flexibility, and low-temperature properties, so it is used in many electronic devices, such as light control. It is thought that it can be used as an electrolyte in a wide range of fields such as glass, display elements, and batteries.

[Examples] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples unless it exceeds the gist thereof.

Example 1 Molybdophosphoric acid-ethanol-various silicate-based molybdenum
Butyric acid (H3M O12P 040・29H2
0) 9.46g was dissolved in 4g of ethanol and stirred for 10 minutes. Next, tetraethyl silicate (St
3.75 g of (OEt)4) was added and further stirred for 60 minutes. The molar ratio at this time was heteropolyacid/ethylsilicate=10 moj2%/90 mofL%. When 1.0 g of pure water was added to this solution and stored in a glass container, the solution gradually became non-liquid after 2 days and became a transparent green semi-solid.

Two platinum electrodes placed parallel to each other were immersed in this semi-solid material, and AC impedance was measured at 24°C (measurement range: fmaX = 20kHz.

fmln=0. 05HZ) to obtain the Cole-Cole plot shown in FIG.

Calculations based on this value revealed that a semi-solid electrolyte having an extremely high ionic conductivity of 4×10 −2 S −cm −′ at room temperature was obtained.

Furthermore, this semi-solid material was cooled and the low-temperature characteristics were examined. The results are shown in FIG. 2 N011. The activation coefficient E obtained from this is approximately 24Kcafl-moρ,
It was confirmed that the temperature dependence was relatively small.

In addition, in the above procedure, instead of the ethanol-tetraethylsilicate combination, propyl alcohol-tetraprobyl silicate system and butyl alcohol-tetrabutyl silicate system were synthesized in the same manner, resulting in a semi-solid product. was produced and showed comparable high ionic conductivity.

Example 2 Hydrous antimony oxide-water-tetraethylsilicate 5.0 g of antimony pentachloride (sbcΩa) and 3.1 g of antimony trichloride (SbCIl,s) were each dissolved in 6.0 g of dilute hydrochloric acid, and pure water was added to each. A hydrated oxide with a valence of was synthesized. Some of them were redissolved by the generated protons and became a clear solution. These were mixed, 20 g of tetraethyl silicate was further added, and the mixture was stirred and left to stand. As a result, a semi-solid state was obtained by hydrolysis, and a semi-transparent ionic conductor was obtained. This material then gradually turned white, and oxides of metals of different valences were uniformly dispersed in the semi-solid material together with water.

The ionic conductivity of the obtained semi-solid material was measured in the same manner as in Example 1, and the ionic conductivity at room temperature was 4.5 x 10-'S.cm-'.

Example 3 Triethyl phosphate-ethanol-tetraethylsilicate system 10 g of ethanol and 2.0 g of 6 wt % dilute nitric acid were added to 10 g of tetraethyl silicate, and 3.0 g of 6 wt % diluted nitric acid was added. After adding Og, the mixture was refluxed for 3 hours in a constant temperature bath at 70°C to perform hydrolysis in advance. Furthermore, triethyl phosphate (Q=p (O
Add Et)3) (silicon; phosphorus; 11 (molar ratio)),
Reflux was performed at 70'C for 14 hours. The solution turned white very slowly and became semi-solid. When the ionic conductivity of the obtained semi-solid material was measured in the same manner as in Example 1, the ionic conductivity at room temperature was 3.2 x 10
-'S -am-'.

Example 4 Tungstophosphoric acid (H3W, 2P04o/29H20)
Take 102g of ethylene glycol (C2H4(OH)
)2) Dissolved in 12.0g.

3.54 g of tetraethyl silicate was added to the colander and upon standing, a transparent semi-solid material was formed. The ionic conductivity of the obtained semi-solid material was measured in the same manner as in Example 1, and it was found to be 4.7x10-0-3 S-C at room temperature.
'Met.

We also investigated the temperature dependence of the ionic conductivity of this sample.
It is shown in Figure No. 2. The activation energy E obtained from this is 1.5Kcau-mof! , -', and it was confirmed that the temperature dependence was very small.

Example 5 Nitric acid-1,3-butanediol-tetraethylsilicate A solution of 2 g each of nitric acid and pure water was mixed with 10 g of 1.3
- It was added to butanediol and stirred well. 8.25 g of tetraethyl silicate was added to this and dispersed using ultrasonic waves. The solution remained transparent and semisolid. The ionic conductivity of the obtained semi-solid material was measured in the same manner as in Example 1, and it was found to be 4°58X 10-3S -Cm
-' cleared it.

Example 6 1.0 g of lithium perchlorate (LiCfl○4) was dissolved in 11.3 g of brobylene carbonate to form a homogeneous solution.

10.0 g of tetraethyl silicate was added to this solution, and ultrasonic dispersion and stirring were repeated. The solution remained transparent and semisolid. The ionic conductivity of the obtained semi-solid material is 7
．． It became 2X10-'S-cm-'.

Comparative Example I P E OL i CF 3 S O 3 type (organic lithium ion conductor) The lithium ion conductivity caused by the interaction between the ether group -〇- in polyethylene oxide, which is a flexible polymer chain, and Li CF 3 SO 3 is as follows. Since this is well known, we investigated this conductivity. Here, the PEO complex was prepared using a known method (J, Electrochem, S
ac, 133 (1986) 315 and references therein). The ionic conductivity of the obtained composite at room temperature is very low at a = 1-98・Cm''.
When determining the activation energy E regarding temperature dependence, as shown in Figure 2 No. 3, E = 10Kcafl-m
It was a very large value of 0°C-1. In FIG. 2, the line No. 3 is drawn to show the slope of the EPOLiCF3 S03 system, and its absolute value is actually very low at 10-9.

[Effects of the Invention] As is clear from the results of the above Examples and Comparative Examples, the semi-solid electrolyte of the present invention has extremely high ionic conductivity, and its temperature dependence is also extremely small.

In the semi-solid electrolyte of the present invention, the hydrolyzate of silicon alkoxide such as ethyl silicate that forms the matrix is hardly involved in ionic conductivity;
By including the ionic conductor in the skeleton, its function is fully demonstrated. This matrix portion is amorphous and is expected to have high ionic conductivity due to its open structure. Furthermore, it has excellent homogeneity, isotropy, moldability, and processability.
It also has the advantage that it can be easily made into a thin film and the chemical composition can be easily controlled. ("Chemistry J 11, 332゜1986).

Furthermore, the flexibility and deformability of the skeleton increases the degree of freedom for protons, which are mobile electrodes, and also retains within the skeleton the liquid that acts as a medium for hydrogen bonding, which is essential for proton conductivity. It also has For this reason,
It is believed that it is possible to exhibit high ionic conductivity that was previously unattainable. In addition, it also has the non-leak property that is an inherent feature of solid electrolytes, and also improves its flexibility, freedom of shape, processability, softness, and low-temperature properties, which had been considered disadvantageous.

Therefore, according to the present invention, (1) ionic conductivity is high.

■ Low electronic conductivity.

■ Low temperature dependence of ionic conductivity.

■ High decomposition voltage.

■ Excellent stability.

■ Wide stable temperature range.

■ Small specific gravity.

■ Excellent workability and handling.

An electrolyte is provided that has excellent characteristics such as: In the present invention, the ionic species is not limited to protons, but can also be realized by containing salts or solvents having conductive species ions that can be ionized, and the range of application is extremely wide.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the Cole-Cole plot diagram obtained in Example 1, and FIG. 2 is a graph showing the temperature dependence of the sample obtained in Example 1.3 and Comparative Example 1. Representative Patent Attorney Tsuyoshi Shigeno

Claims (1)

[Claims] (1) A semi-solid characterized by adding at least one substance that causes ionic conductivity selected from the following [a] to [e] to a silicon alkoxide, and then polymerizing the alkoxide by a hydrolysis reaction. Method for producing electrolyte. [a] Hydrous metal oxide M_xO_y·nH_2O, which exhibits ionic conductivity of 10^-^6S·cm^-^1 or more at 25°C and is represented by the following general formula (where M=Zr, Sn, V, Sb, Th, Cr, In, Ga, Ce, Nb, Ta, Y, Ti) [b] An inorganic or organic salt of metal M in [a] above dissolved in a solvent compatible with silicon alkoxide [ c] An ion-conductive inorganic compound dissolved in a solvent compatible with silicon alkoxide [d] Alkoxide of an element other than silicon [e] Inorganic acid or organic acid solution