JP2003051428A - Gel electrolyte forming composition, the gel electrolyte and method for manufacturing the gel electrolyte - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gel electrolyte forming composition, which exhibits high electrolytic solution retention, moreover exhibits high ion conductivity and can be gelled, after being poured as a liquid into a gap formed by placing electrodes at specific intervals, to provide a gel electrolyte which is formed by bridging the composition, and to provide its method of manufacture. SOLUTION: The gel electrolyte forming composition contains monovinyl monomer and polyvinyl monomer as polymeric components. In this case, the monovinyl monomer contains polyalkylene glycol mono (metha) acrylate as the main component and the polyvinyl monomer contains polyalkylene glycol di(metha) acrylate as the main component.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a gel electrolyte-forming composition that can be used as an electrochemical device such as a battery and a capacitor, a gel electrolyte, and a method for producing the same. The gel electrolyte-forming composition and gel electrolyte of the present invention,
In particular, it can be suitably used for an electric double layer capacitor.

[0002]

2. Description of the Related Art Among electric capacitors, electric double layer capacitors, which are widely used due to their large capacity, conventionally have a structure in which a liquid electrolyte is used and this is enclosed in a metal case. When an overvoltage higher than the rated voltage is applied during use, the internal temperature rises, the internal pressure of the metal case rises, and the liquid organic solvent forming the electrolyte may leak. . That is,
It has not been possible to sufficiently deal with the leakage of the electrolytic solution by using the conventional liquid electrolyte.

Further, the liquid electrolyte has no shape-retaining property,
The manufacturing process of batteries and capacitors is limited, and special consideration must be given to the liquid leakage resistance of products, and improvements have been required.

As a technique for improving the resistance to liquid leakage and maintaining the degree of freedom of processing, there is a method of making the electrolytic solution non-fluidized to meet the above-mentioned demand. By mixing a crosslinked vinyl polymer and the electrolytic solution. A technique using a gel electrolyte is disclosed in Japanese Patent Laid-Open No. 5-325.
It is disclosed in Japanese Patent No. 986.

[0005]

The gel electrolyte disclosed in the above publication is produced by synthesizing a polymer, followed by purification and drying.
After that, the electrolytic solution is mixed. This technology
It has the following problems. (1) The electrolytic solution retention rate in the gel electrolyte is about 5 times the polymer component, the ratio of the polymer component having high specific resistance is high, and the ion conductivity is low, which is not satisfactory. (2) There are many manufacturing steps for manufacturing a gel electrolyte,
Since the electrolyte is mixed after the polymer is produced, it can be applied to capacitors such as electric double layer capacitors.
The degree of freedom in manufacturing is small, because it is necessary to separately manufacture different sizes according to the type.

In the manufacturing and processing steps of batteries and capacitors, the degree of freedom in processing is high. Therefore, after disposing electrodes and separators in a case in a structure required for various batteries, capacitors, etc., an electrolytic solution is formed. A battery and a capacitor are manufactured by pouring into a predetermined space and sealing. Therefore, even when a gel electrolyte is used, in order to maintain the degree of freedom of processing, the gel electrolyte forming composition is poured into a predetermined space formed by an electrode or a separator arranged in the case and then polymerized. Processability capable of reacting and curing a sexual component to form a gel is required. However, the technique disclosed in Japanese Patent Laid-Open No. 5-325986 cannot meet such a request.

Therefore, an object of the present invention is to have a high electrolytic solution retention rate and therefore a high ionic conductivity, and further, it is possible to gel after pouring in a liquid state into a void formed by arranging electrodes at a predetermined interval. A gel electrolyte forming composition, a gel electrolyte obtained by crosslinking the gel electrolyte composition, and a method for producing the same.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to solve the above problems, and as a result, by using a gel electrolyte forming composition containing a monomer having a polyalkylene glycol chain as a main component, The present inventors have found that polymerization in an electrolytic solution is possible and that the electrolytic solution retention rate is improved, and have completed the present invention.

That is, the gel electrolyte forming composition of the present invention is a gel electrolyte forming composition containing a monovinyl monomer and a polyvinyl monomer as polymerizable components, wherein the monovinyl monomer is polyalkylene glycol mono (meth) acrylate. Is contained as a main component, and the polyvinyl monomer contains polyalkylene glycol di (meth) acrylate as a main component.

As described above, by using the monovinyl monomer having a polyalkylene glycol chain and the polyvinyl monomer as the polymerizable component, the polymerization in the electrolytic solution is possible and the electrolytic solution can be obtained. The retention rate can be improved. Although the details of the reason are unknown, it is presumed that the presence of the polyalkylene glycol chain enhances the affinity with the non-aqueous electrolyte solution and that the crosslinking reaction by the polyvinyl monomer preferably proceeds. In the present invention, the main component may be 100%,
This means that a small amount of other components may be contained as long as the effect is not impaired.

In order to more surely improve the polymerizability in the electrolytic solution and the electrolytic solution retention rate, the polyalkylene glycol mono (meth) acrylate and the polyalkylene glycol of the polyalkylene glycol di (meth) acrylate are used. The degree of polymerization of the chains is preferably 1-15.

Further, from the viewpoint of further improving the polymerizability in the electrolytic solution and the electrolytic solution retention rate by the ratio of the monovinyl monomer and the polyvinyl monomer, polyalkylene glycol mono (meth) acrylate / polyalkylene glycol di (meth) acrylate. Has a molar ratio of 30/7
It is preferably 0 to 99/1.

The above-mentioned gel electrolyte forming composition can be used by adding an electrolytic solution, but it is preferable to preliminarily include an electrolytic solution in which an electrolyte is dissolved in an organic solvent. The organic solvent at that time is more preferably a carbonate compound. By carrying out the polymerization in a state where the electrolytic solution is added, the electrolytic solution is easily incorporated into the polymer skeleton, and the retaining force of the electrolytic solution by the gel is also improved.

Specifically, after the electrodes and the separator are arranged in the case in a structure required for various batteries, capacitors, etc., they are poured into a predetermined space and cured, whereby the battery and the capacitor can be easily prepared. It is possible to manufacture a gel electrolyte that constitutes At that time, by using a carbonate compound as the organic solvent, a gel electrolyte forming composition suitable for forming a gel electrolyte of a capacitor such as an electric double layer capacitor can be obtained.

The above gel electrolyte forming composition can be polymerized in the state where various polymerization initiators are added,
It is preferable to contain a radical polymerization initiator in advance.

On the other hand, the gel electrolyte of the present invention is a gel electrolyte gelled by the polymerization of the polymerizable component of the gel electrolyte-forming composition described above. The retention rate is high, and therefore the ionic conductivity is high, and the manufacturing process is simple.

On the other hand, in the method for producing a gel electrolyte of the present invention, since the above gel electrolyte forming composition containing a radical polymerization initiator is heated to gel, the electrodes are arranged at predetermined intervals. It is possible to obtain a gel electrolyte which can be gelled after being poured in a liquid form into the voids formed as described above, and which has a high electrolytic solution retention rate and therefore a high ionic conductivity. As a result, a variety of products can be manufactured with a simple manufacturing process.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. The gel electrolyte-forming composition of the present invention is a composition used for forming a gel electrolyte, and contains a monovinyl monomer and a polyvinyl monomer as polymerizable components.

The monovinyl monomer contains polyalkylene glycol mono (meth) acrylate as a main component. In the present invention, (meth) acrylate means either or both of acrylate and methacrylate.

Examples of the alkylene group constituting the polyalkylene glycol chain (polyoxyalkylene chain) of the polyalkylene glycol mono (meth) acrylate include ethylene, methylene, propylene, butylene, or two or more thereof. Is most preferred. The degree of polymerization of the polyalkylene glycol chain is preferably 1 to 15, more preferably 1 to 10. When the degree of polymerization of the polyalkylene glycol chain is less than 1, the affinity with the non-aqueous electrolyte solution decreases, and the gel tends to be non-uniform. Further, when the degree of polymerization exceeds 15, the gel strength tends to decrease and the composition tends to fluidize.

The other end of the polyalkylene glycol mono (meth) acrylate may remain a hydroxyl group,
It may be alkoxylated. Examples of the alkyl group at the time of alkoxylation include an alkyl group having 1 to 4 carbon atoms.

The polyvinyl monomer contains polyalkylene glycol di (meth) acrylate as a main component. Examples of the alkylene group constituting the polyalkylene glycol chain include ethylene, methylene, propylene, butylene, and two or more thereof, with ethylene being most preferable. The degree of polymerization of the polyalkylene glycol chain is preferably 1 to 15, more preferably 1 to 10. When the degree of polymerization of the polyalkylene glycol chain is less than 1, the affinity with the non-aqueous electrolyte solution decreases and the gel tends to be non-uniform. Further, when the degree of polymerization exceeds 15, the gel strength tends to decrease, and fluidization tends to occur.

The molar ratio of polyalkylene glycol mono (meth) acrylate / polyalkylene glycol di (meth) acrylate is preferably 30/70 to 99/1, more preferably 50/50 to 99/1. If the molar ratio of both is less than 30/70, the crosslinking density tends to be high and the electrolytic solution retention rate tends to be low, and if it exceeds 99/1, it tends to be difficult to obtain a gelled product.

As another polymerizable component of the gel electrolyte-forming composition of the present invention, if necessary, other vinyl monomer may be used in combination so long as the characteristics of the gel electrolyte of the present invention are not significantly impaired. As such a monomer, a known compound can be used without particular limitation, and specifically,
Styrene-based monomers such as styrene and α-methylstyrene, alkyl mono (meth) acrylates such as butyl (meth) acrylate, vinyl halides such as vinyl chloride,
Examples thereof include vinyl ethers, vinyl alcohol derivatives such as vinyl acetate, trimethylolpropane triacrylate, difunctional monomers such as divinylbenzene, and the like. These vinyl monomers may be used alone or in combination of two or more.

As the initiator to be used, a known radical polymerization initiator such as a peroxide polymerization initiator or an azo polymerization initiator can be used. Specifically, as the peroxide-based polymerization initiator, for example, benzoyl peroxide,
Methyl ethyl ketone peroxide, t-butyl peroxypivalate, diisopropyl peroxy carbonate, dicumyl peroxide, di t-butyl peroxide, t-butyl hydroperoxide, t-butyl peroxybenzoate and the like are mentioned, and azo polymerization. Examples of the initiator include 2,2′-azobis (2-isobutyronitrile), 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), 1 , 1′-azobis (cyclohexane-1-carbonitrile) and the like. These may be used alone or in combination of two or more. The addition amount of these thermal polymerization initiators is not limited as long as a gel electrolyte can be obtained, but is generally 0.1 to 2% by weight with respect to the reactive component from the viewpoint of electric characteristics as an electrolyte. %.

When the composition is irradiated with energy rays such as visible rays, ultraviolet rays and electron rays to be cured, it is preferable to use a photosensitizer together. As such a photosensitizer, known photosensitizers can be used without limitation, and benzoin-based photosensitizers, acetophenone-based photosensitizers, benzyl ketal-based photosensitizers and the like can be used. It is illustrated. Specifically, acetophenone, benzophenone, 4-methoxybenzophenone, benzoin methyl ether, 2,2-dimethoxy-
2-phenyldimethoxy-2-phenylacetophenone, benzyl, benzoyl, 2-methylbenzoin, 2
-Hydroxy-2-methyl-1-phenyl-1-one,
1- (4-isopropylphenyl-2-hydroxy-2
-Methylpropan-1-one, triphenylphosphine, 2-chlorothioxanthone and the like are exemplified. These may be used alone or in combination of two or more.
The amount of these photosensitizers added is not limited as long as it exerts a sensitizing action, but is usually 0.1% by weight to 2% by weight with respect to the reactive component.

The initiator and photosensitizer may be added to the gel electrolyte-forming composition from the beginning or before use.

As the organic solvent constituting the electrolytic solution, one that can dissolve the electrolyte to a required concentration is used. Specifically, a highly polar organic solvent such as a carbonate-based solvent, a lactone-based solvent or an alcohol-based solvent, preferably an organic solvent which is liquid at room temperature is used. It is particularly preferable to use a carbonate-based solvent as the gel electrolyte for the electric double layer capacitor. When two or more organic solvents are used in combination, it is also preferable that the mixture be liquid at room temperature.

Examples of carbonate solvents include ethylene carbonate and propylene carbonate.
Specific examples of the lactone solvent include γ-butyrolactone, γ-valerolactone, δ-valerolactone, 3-methyl-1,3-oxazolidin-2-one, 3-ethyl-1,3-oxazolidine-2-. ON and the like are exemplified.

As the alcoholic solvent, alcohols which are liquid at room temperature can be used without limitation, and monoalcohols such as n-butanol, i-butanol and methyl cellosolve, polyhydric alcohols such as ethylene glycol, propylene glycol and diethylene glycol. The kind is illustrated.

If necessary, other organic solvent may be added to the above-mentioned solvent within a range that does not impair the characteristics thereof. Examples of the organic solvent include pyrrolidone-based solvents such as N-methylpyrrolidone, N, N-dimethylformamide, N, N-
Amide solvents such as dimethylacetamide, ether solvents such as tetrahydrofuran, dioxane, 1,2-dimethoxyethane, dibutyl ether, acetonitrile, 3
-Nitrile solvent such as methoxypropionitrile, 1,
Examples thereof include imidazolidinone-based solvents such as 3-dimethyl-2-imidazolidinone and sulfolane-based solvents such as sulfolane and 3-methylsulfolane. These may be used alone or in combination of two or more.
Among these non-aqueous solvents, it is particularly preferable to use carbonate-based solvents, ether-based solvents and cyclic ether-based solvents.

The above organic solvent may contain a small amount of water depending on the use of the condenser. When used in an electric double layer capacitor, it is preferable to use a solvent having a water content as low as possible.

The gel electrolyte forming composition of the present invention and the electrolyte as a constituent of the gel electrolyte may be an alkali metal salt, a quaternary ammonium salt, an alkaline earth metal salt, etc., depending on the intended use of the gel electrolyte. It is appropriately selected without limitation from known electrolytes.

Specifically, examples of the alkali metal salt include
For example, LiClO_Four , LiSCN, LiBF_Four , LiA
sF₆ , LiCF₃ SO₃ , NaI, NaSCN, Na
ClO_Four , NaBF_Four , NaAsF₆ , KSCN, etc.
You can Examples of the quaternary ammonium salt include (CH₃ )
_Four NBF_Four , (C₂ H_Five )_Four NBF_Four , (N-C_Four H
₉ )_Four NBF_Four , (C₂ H_Five )_Four NBr, (C₂ H_Five )
_Four NClO_Four , (N-C _Four H₉ )_Four NClO_Four Etc.
To be Further, as the alkaline earth metal salt, for example,
Mg (ClO_Four )₂ , Ca (ClO_Four )₂ , Mg (BF
_Four )₂ , Ca (BF_Four )₂ , Imidazolium phthalate
Salt, quaternary ammonium salt of phthalic acid, etc.
Ammonium salts may be mentioned. These electrolytes are used alone.
They may be used, or two or more kinds may be used in combination.

The amount of the electrolyte added to the organic solvent is not particularly limited as long as it functions as an electrolyte and depends on the solubility of the electrolyte in the solvent, but it is 0.5 with respect to the organic solvent.
~ 2mol / L, preferably 0.7-1.5mo
1 / L.

The content of the electrolytic solution contained in the gel electrolyte-forming composition or the gel electrolyte of the present invention is preferably 70 to 95% by weight, more preferably 90 to 95% by weight. 7
If it is less than 0% by weight, the ionic conductivity tends to be insufficient.

The method for producing a gel electrolyte according to the present invention heats the above gel electrolyte forming composition to gel it. The heating temperature is preferably 60 to 100 ° C., and the heating time is 0.5 to 2 depending on the heating temperature.
It's about time. The gel electrolyte-forming composition of the present invention,
It is also possible to irradiate with energy rays such as visible light, ultraviolet rays and electron beams to cause gelation, but it is preferable to cause gelation by heating in the production method.

Specifically, the gel electrolyte used in capacitors such as electric double layer capacitors, batteries, etc., has, for example, an activated carbon electrode or the like arranged in a predetermined form, and the gel electrolyte is placed in the void formed by the activated carbon electrode. It is formed by pouring the forming composition and then gelling it by means such as heating. It can also be produced by coating an activated carbon electrode with a gel electrolyte-forming composition to a predetermined thickness, heating and irradiating with energy rays to cause gelation, and winding the resulting laminate. The gel electrolyte-forming composition of the present invention can be applied to capacitors and the like by any method and has a high degree of freedom in processing.

[0039]

EXAMPLES Examples and the like specifically showing the constitution and effects of the present invention will be described below.

(Example 1) Methoxy polyethylene glycol
Monomethacrylate (made by NOF Corporation, trade name Bremma
-PME-400, degree of polymerization of ethylene glycol 9) 1
g (2.0 x 10 ^-3Mol) and polyethylene glycol
Dimethacrylate (made by NOF CORPORATION, trade name Blemmer PD
E-400, degree of polymerization of ethylene glycol 9) 1 g
(1.8 × 10 ^-3(Mol) and room temperature
(A) was obtained. To 2 g of this polymerizable component (A), a carb
Nate-based solvent (propylene carbonate, hereinafter abbreviated as PC)
As an electrolyte.
Electrolyte solution containing luoroborate dissolved at a concentration of 1 mol / L
20 g of t-butylperoxide as a radical polymerization initiator
Xybenzoate (Nippon Oil & Fats, trade name Perbutyl Z)
Add 0.04g and mix at room temperature to form gel electrolyte
A composition was obtained. The gel electrolyte-forming composition was heated to 80 ° C.
The gel electrolyte (a) is obtained by heating for 1 hour.
It was

Example 2 Polyethylene glycol monomethacrylate (manufactured by NOF CORPORATION, trade name Blemmer PE-)
200, degree of polymerization of ethylene glycol 9) 1 g (3.5
X 10 ^-3 mol) and polyethylene glycol dimethacrylate (manufactured by NOF CORPORATION, trade name Blemmer PDE-40)
0, degree of polymerization of ethylene glycol 9) 1 g (1.8 × 1)
0 ^-3 mol) and give the mixture the polymerization component at room temperature (B). To 2 g of this polymerizable component (B), 20 g of an electrolytic solution prepared by dissolving tetraethylammonium tetrafluoroborate as an electrolyte at a concentration of 1 mol / L in PC, and t-butylperoxybenzoate (manufactured by NOF CORPORATION) as a radical polymerization initiator. 0.04 g of trade name Perbutyl Z) was added and mixed at room temperature to obtain a gel electrolyte forming composition. The gel electrolyte (b) was obtained by heating this gel electrolyte forming composition at 80 ° C. for 1 hour.

Comparative Example 1 1.4 g of styrene, 0.5 g of n-butyl acrylate, and 0.1 of divinylbenzene.
A polymerizable component was obtained by mixing g at room temperature. To 2 g of this polymerizable component, the same electrolyte solution and initiator as used in Example 1 were added and mixed in the same amount to obtain a gel electrolyte forming composition. This gel electrolyte forming composition
When heated at 0 ° C. for 1 hour, although a gel electrolyte was obtained, the gel state was cloudy and the phenomenon that the electrolytic solution oozes out from the gel was observed.

Comparative Example 2 1.4 g of styrene, 0.5 g of n-butyl acrylate, and 0.1 of divinylbenzene.
g, t-butylperoxybenzoate (Nippon Yushi-Seiya, trade name Perbutyl Z) as a radical polymerization initiator.
04 g was added and stirred to sufficiently disperse. After sufficiently replacing the inside of the reactor with nitrogen, it was heated at 80 ° C. for 1 hour to obtain a polymer. To 2 g of this polymer, 1 mo of tetraethylammonium tetrafluoroborate as an electrolyte was added to PC.
The electrolytic solution dissolved at a concentration of 1 / L was gradually added and mixed at room temperature. However, the content of the electrolyte in the gel should be 8
It could not be 3% by weight or more. The gel electrolyte having this content was used as a sample for measuring ionic conductivity.

Reference Example 1 Methoxy polyethylene glycol
Monomethacrylate (made by NOF Corporation, trade name Bremma
-PME-400, degree of polymerization of ethylene glycol 9) 1
g (2.0 x 10 ^-3Mol) and polyethylene glycol
Dimethacrylate (made by NOF CORPORATION, trade name Blemmer PD
E-400, degree of polymerization of ethylene glycol 9) 1 g
(1.8 × 10 ^-3Mol) and as a radical polymerization initiator
t-Butyl peroxybenzoate (made by NOF Corporation, product
Add 0.04 g of perbutyl Z), stir, and mix well.
Dispersed. After thoroughly replacing the inside of the reactor with nitrogen, raise the temperature to 80 ° C.
And heated for 1 hour to obtain a polymer. To 2 g of this polymer,
Tetraethylammonium tetraf as an electrolyte in PC
Electrolyte solution containing luoroborate dissolved at a concentration of 1 mol / L
Was added and mixed at room temperature. However, the gel
-Like electrolyte was not obtained, and the gel-like electrolytes of Examples 1 and 2 were obtained.
It was found that the electrolyte retention rate was lower than that of

Reference Example 2 Methoxypolyethylene glycol monomethacrylate (manufactured by NOF CORPORATION, trade name Bremmer PME-400, ethylene glycol polymerization degree 9)
0.2 g (0.4 × 10 ⁻³ mol) and polyethylene glycol dimethacrylate (manufactured by NOF CORPORATION, trade name Blemmer PDE-400, ethylene glycol polymerization degree 9)
1.8 g (3.3 × 10 ⁻³ mol) was mixed at room temperature to obtain a polymerizable component (C). 2 g of this polymerizable component (C)
In addition, 20 g of an electrolytic solution prepared by dissolving tetraethylammonium tetrafluoroborate as an electrolyte in PC at a concentration of 1 mol / L, and 0.04 g of t-butyl peroxybenzoate (manufactured by NOF Corporation, trade name Perbutyl Z) as a radical polymerization initiator. The mixture was added and mixed at room temperature to obtain a gel electrolyte-forming composition. 80% of this gel electrolyte forming composition
By heating at ℃ for 1 hour, gel electrolyte (c)
Got The gel state was cloudy, and the phenomenon that the electrolyte oozes out from the gel was observed.

(Measurement of Ionic Conductivity) The ionic conductivity of the gel electrolyte obtained above was measured at 20 ° C. by the complex AC impedance method. The measurement results of the ionic conductivity are shown in Table 1 together with the content of the electrolytic solution in the gel and the gel state.

[0047]

[Table 1] * 1: It is an apparent amount, and the actual content as a gel is lower than this.

As shown in the results of Table 1, the gel electrolyte of the present invention is excellent in that the content of the electrolytic solution in the polymer can be increased, the appearance is transparent, and the ionic conductivity is high. It was On the other hand, in the conventional compositions using the monomers having no polyalkylene glycol chain (Comparative Examples 1 and 2), polymerization in the electrolytic solution resulted in a non-uniform gel with a cloudy appearance, and the polymer was converted into the electrolytic solution. In the case of containing, the content was low and the ionic conductivity was also low. In addition,
As shown in Reference Examples, the gel electrolyte-forming composition of the present invention is preferably polymerized in an electrolytic solution, and in particular, the molar ratio of monovinyl monomer to polyvinyl monomer is 30.
It is preferably / 70 to 99/1.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01M 6/18 H01M 6/22 C 6/22 10/40 B 10/40 H01G 9/00 301D (72) Inventor Takashi Oga 1-17-18 Edobori, Nishi-ku, Osaka City, Osaka Prefecture Toyo Tire & Rubber Co., Ltd. F-term (reference) 4J027 AC02 AC03 AC04 AC06 AJ02 AJ08 BA01 BA07 BA19 BA20 BA21 CA14 CB03 CB10 CC02 CC03 4J100 AL08P AL66Q BA03P BA08P BA08Q CA04 CA23 DA40 EA03 JA45 5G301 CD01 5H024 AA00 BB01 DD00 EE09 FF15 FF23 GG01 HH08 5H029 AJ06 AJ14 AM00 AM03 AM07 AM16 CJ02 DJ09 HJ10

Claims (8)

[Claims] 1. A gel electrolyte forming composition containing a monovinyl monomer and a polyvinyl monomer as a polymerizable component, wherein the monovinyl monomer contains polyalkylene glycol mono (meth) acrylate as a main component, and the polyvinyl monomer is poly A gel electrolyte-forming composition comprising alkylene glycol di (meth) acrylate as a main component. 2. The gel electrolyte forming composition according to claim 1, wherein the polyalkylene glycol mono (meth) acrylate and the polyalkylene glycol di (meth) acrylate have a polyalkylene glycol chain having a degree of polymerization of 1 to 15. 3. Polyalkylene glycol mono (meth)
The gel electrolyte forming composition according to claim 1 or 2, wherein the molar ratio of acrylate / polyalkylene glycol di (meth) acrylate is 30/70 to 99/1. 4. The gel electrolyte forming composition according to claim 1, further comprising an electrolytic solution in which an electrolyte is dissolved in an organic solvent. 5. The gel electrolyte forming composition according to claim 4, wherein the organic solvent is a carbonate compound. 6. The gel electrolyte forming composition according to claim 1, further comprising a radical polymerization initiator. 7. A gel electrolyte, which is gelled by polymerizing the polymerizable component of the gel electrolyte forming composition according to claim 4. 8. A method for producing a gel electrolyte, wherein the gel electrolyte forming composition according to claim 6 is heated to gel.