JP2011198691A - Gel ion conductor and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gel ion conductor having high transparency, which is equipped with high electrolytic solution holding power and mechanical strength (shape maintaining characteristics against external stress).SOLUTION: The gel ion conductor contains polyurethane as a matrix material of gel, a nonaqueous solvent, and electrolyte. The polyurethane has a cross-linked structure derived from polycaprolactone polyol having at least two or more hydroxyl groups in a molecule, and a compound (wherein at least three or more of either hydroxyl group or isocyanate group are contained therein) having at least two or more isocyanate groups in a molecule.

Description

  The present invention relates to a gel ion conductor and a method for producing the same. More specifically, the present invention relates to a gel ion conductor that can contain a large amount of a non-aqueous solvent and is excellent in mechanical strength, and a method for producing the same.

  The ionic conductor (electrolyte) is a constituent requirement for electrochemical devices such as lithium ion secondary batteries, wet photovoltaic cells, capacitors, and electric double layer capacitors. When the electrolyte is liquid, accidents such as liquid leakage, heat generation due to a short circuit, and ignition may occur.

Therefore, in the electrochemical device, for the purpose of preventing leakage of the electrolytic solution, a gel electrolyte in which a solvent is contained in the polymer has been proposed. For example, a gel electrolyte is known in which a non-aqueous electrolyte solution in which a lithium ion compound is dissolved in a polyether polyurethane is impregnated and held to form a gel (see Patent Document 1).
The gel electrolyte of Patent Document 1 is an alternative to the liquid electrolyte that has been used in the past, and is intended to solve the problem of liquid leakage.

JP-A-5-283103

  In general, in an electrochemical device, since the conductivity of an electrolytic solution used influences the characteristics of the device, the gel electrolyte is required to have good conductivity. In order for the gel electrolyte to have good conductivity, it is necessary to be able to contain many electrolyte solutions. However, the gel electrolyte described in Patent Document 1 has a difficulty in increasing the content of the electrolyte because the electrolyte retention capacity, that is, the liquid retention, is not sufficient.

  If the electrolyte is held in a large amount in order to improve conductivity, the gel electrolyte may cause a decrease in shape maintenance against external stress, that is, a decrease in mechanical strength, and further the electrolyte may ooze out. There is also a fear. On the other hand, if the holding amount of the electrolytic solution is suppressed in order to prevent the mechanical strength from being lowered and the electrolytic solution to ooze out, the conductivity is lowered and the performance of the device is lowered. As described above, in the gel electrolyte, it is a technical problem to achieve both high mechanical strength and high conductivity. In addition, if the gel electrolyte can be used, for example, in a device that requires light transmission, a portion that can be seen from the outside, and the like, the range of use of the gel electrolyte is widened, so that a highly transparent one has been desired.

  The present invention solves the above-mentioned problems, and the object of the present invention is to provide a property that can stably contain a large amount of an electrolytic solution and mechanical strength (shape maintainability against external stress), and transparency. Another object of the present invention is to provide a gel-like ionic conductor having a high thickness.

  As a result of earnest research to solve the above problems, the inventors of the present invention cross-linked a polycaprolactone polyol having at least two hydroxyl groups in the molecule and a compound having at least two isocyanate groups in the molecule. The polyurethane obtained by the reaction has a high ability to retain a non-aqueous solvent, and a large amount of solvent can be contained in the gel, so that ion conductivity is good, shape maintenance is excellent, and high transparency is achieved. As a result, the present invention was found.

  Thus, according to the present invention, it is a gel-like ionic conductor containing a polyurethane as a gel matrix material, a non-aqueous solvent, and an electrolyte, and the polyurethane has a polycaprolactone having at least two hydroxyl groups in the molecule. Gel having a crosslinked structure derived from a polyol and a compound having at least two or more isocyanate groups in the molecule (provided that any one of the hydroxyl group and the isocyanate group is at least three). A ionic conductor is provided.

  Further, according to the present invention, in a non-aqueous solvent containing an electrolyte, a polycaprolactone polyol having at least two hydroxyl groups in the molecule and a compound having at least two isocyanate groups in the molecule (however, the hydroxyl group And at least three of the isocyanate groups) are subjected to a cross-linking reaction to obtain a gel ion conductor.

  Since the gel-like ionic conductor according to the present invention can stably contain a large amount of an electrolytic solution containing a non-aqueous solvent and an electrolyte, the ionic conductivity is high and there is little risk of leakage. In addition, since the mechanical strength is high, the shape maintaining property against external stress is excellent. Furthermore, it has high transparency. Thus, the gel ion conductor according to the present invention, which has solved the problems of conventional gel ion conductors, can be used in electrochemical devices such as lithium ion secondary batteries, wet photovoltaic cells, capacitors, and electric double layer capacitors. It can be suitably used. In addition, it can be used in new fields such as light-controlling materials such as light-controlling glass that uses electrochromic phenomenon that develops color tone changes by applying voltage, and new recording medium materials that apply the principle of photoelectrochemistry. I can expect.

  In addition, when the polycaprolactone polyol having at least two hydroxyl groups in the molecule is polycaprolactone diol or polycaprolactone triol, the ion conductivity can be further increased, the gel has excellent mechanical strength and high transparency. A ionic conductor is obtained.

In addition, the compound having at least two isocyanate groups in the molecule is represented by the following formula:
(In the formula, R ^{1 to} R ³ are the same or different alkylene groups having 1 to 8 carbon atoms.)
In the case of a compound represented by the formula (I), a gel-like ionic conductor can be obtained that can further increase ionic conductivity, has excellent mechanical strength, and has high transparency.

  Further, when the total amount of the non-aqueous solvent and the electrolyte is 200 to 500 parts by weight with respect to 100 parts by weight of the polyurethane as the gel matrix material, the ion conductivity can be further increased, the mechanical strength is excellent, and the transparency is high. A gel-like ionic conductor having the following is obtained.

  Further, when the electrolyte is contained in the non-aqueous solvent at a concentration of 0.1 to 15 mol / l, a gel-like ionic conductor having higher ionic conductivity, excellent mechanical strength and high transparency can be obtained. can get.

  Further, when the non-aqueous solvent is at least one aprotic solvent selected from the group consisting of a carbonate ester, a lactone compound, a sulfolane compound, a lactam compound, and a phosphate compound, the ion conductivity is further increased. A gel-like ionic conductor having high mechanical strength and high transparency can be obtained.

  Further, when the electrolyte is at least one electrolyte selected from a lithium salt and a potassium salt, a gel-like ionic conductor that can further increase the ionic conductivity, has excellent mechanical strength, and has high transparency is obtained. It is done.

  Moreover, the above-mentioned problem that the conventional gel-like ionic conductor has can be solved by the method for producing a gel-like ionic conductor according to the present invention. That is, it is possible to produce a gel-like ionic conductor that can stably contain a large amount of electrolytic solution, has excellent mechanical strength, and has high transparency.

  The gel ion conductor according to the present invention includes polyurethane as a gel matrix material, a non-aqueous solvent, and an electrolyte. Polyurethane is a polycaprolactone polyol having at least two or more hydroxyl groups in the molecule and a compound having at least two or more isocyanate groups in the molecule (provided that any one of the hydroxyl groups and isocyanate groups is at least three). It has a crosslinked structure derived from.

The cross-linked structure can be obtained by cross-linking a polycaprolactone polyol having at least two hydroxyl groups in the molecule and a compound having at least two isocyanate groups in the molecule.
By having a crosslinked structure, it can have excellent mechanical strength. Thereby, even if it contains many electrolyte solutions containing a non-aqueous solvent and electrolyte, it will become difficult to leak and the shape maintenance property with respect to an external stress can be improved.

  In addition, in order to have a crosslinked structure, any one of a hydroxyl group and an isocyanate group needs to be three or more. This is because a crosslinked structure cannot be formed when both the hydroxyl group and the isocyanate group are two.

  The polycaprolactone polyol can be produced, for example, by ring-opening polymerization of a caprolactone monomer to the polyol. The properties of the resulting polycaprolactone polyol can be adjusted by the type of polyol used as a raw material and the polymerization degree of caprolactone. A typical structure of a polycaprolactone polyol (polycaprolactone diol or polycaprolactone triol) having 2 or 3 hydroxyl groups in one molecule is shown below. The polycaprolactone polyol has two or more units derived from caprolactone in one molecule.

(In the formula, m is an integer of 0 or more, n is an integer of 1 or more, m + n is 2 or more, and R ¹ represents a divalent organic residue.)

(In the formula, m and p are integers of 0 or more, n is an integer of 1 or more, m + n + p is 2 or more, and R ² represents a trivalent organic residue.)

R ¹ is a polyol having two hydroxyl groups in one molecule, such as ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octane. R ² is derived from a diol or the like, and R ² is a polyol having three hydroxyl groups in one molecule, such as 2-ethyl-2- (hydroxymethyl) -1,3-propanediol (common name: trimethylolpropane), 2- It is derived from (hydroxymethyl) -1,3-propanediol, glycerin, triethanolamine and the like.

  The molecular weight of the polycaprolactone polyol is not particularly limited, but is preferably 500 to 4,000, and more preferably 500 to 2,000.

The polycaprolactone polyol having at least two hydroxyl groups in the molecule is commercially available under the following trade names, and may be arbitrarily selected from these.
Examples of the bifunctional polycaprolactone diol include PLACEL 200 series manufactured by Daicel Chemical Industries, Ltd., depending on the variety and properties, 205, L-205AL, 208, L-208AL, 210, 210N, 212, L-212AL, 220, 220N, 220NP1. , L-220AL, 230, 230-AL, 240.

  Examples of the trifunctional polycaprolactone triol include the PLACEL 300 series manufactured by Daicel Chemical Industries, Ltd., and are classified into products such as 303, 305, 308, 312, L312AL, 320ML, and L320AL depending on the variety and properties.

  Examples of the compound having at least two isocyanate groups in the molecule include diisocyanate compounds such as ethylene diisocyanate, hexamethylene diisocyanate, 2,4-tolylene diisocyanate, naphthalene diisocyanate, methylene bis (4-phenyl isocyanate), and xylylene diisocyanate. Examples include polyisocyanates derived from diisocyanates, such as isocyanurate-modified polyisocyanates, allophanate-modified polyisocyanates, and burette-modified polyisocyanates. Among these, those having the following structure are preferable for imparting electrochemical stability, weather resistance, and gel flexibility.

(In the formula, R ^{1 to} R ³ are the same or different alkylene groups having 1 to 8 carbon atoms.)

Examples of the alkylene group for R ^{1 to} R ³ include methylene, ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, octamethylene and the like. R ^{1 to} R ³ may be alkylene groups having different carbon numbers, but are preferably alkylene groups having the same carbon number.

  In the polymerization of the polyurethane, in order to form a crosslinked structure, a polycaprolactone polyol having two hydroxyl groups and a polyisocyanate having three or more isocyanate groups, or a polycaprolactone polyol having three or more hydroxyl groups and two isocyanates are used. A combination of polyisocyanates having groups is preferred. Further, the reaction ratio between the polyol component and the polyisocyanate component is preferably regulated so that the ratio of the terminal functional groups, that is, the NCO / OH value is 0.5 ≦ NCO / OH ≦ 1.0.

  When the NCO / OH value exceeds 1.0, the terminal NCO is often free, and a volatile component may be generated by reaction with moisture. On the other hand, when it is less than 0.5, there is a possibility that the crosslinking is not sufficiently performed, and the mechanical strength of the ionic conductor may be lowered.

  In the polymerization of polyurethane, a polymerization catalyst may be added to accelerate curing. Examples of the polymerization catalyst include metal oxides, organometallic compounds, and amine catalysts.

  The non-aqueous solvent contained in the gel ion conductor is not particularly limited as long as it is chemically stable, but is more preferable if it can dissolve not only the electrolyte but also the above-mentioned caprolactone polyol and isocyanate. . Examples of such non-aqueous solvents include carbonates such as ethylene carbonate, propylene carbonate, butylene carbonate, diethyl carbonate, dimethyl carbonate, and methyl ethyl carbonate, lactone compounds such as γ-butyrolactone, sulfolane, and methyl sulfolane. Examples include sulfolane compounds, nitrile compounds such as adiponitrile and glutaronitrile, lactam compounds such as N-methylpyrrolidone, and phosphate compounds such as trimethyl phosphate. These may be used singly or in combination of two or more.

  The total content of the non-aqueous solvent and the electrolyte is preferably 200 to 500 parts by weight with respect to 100 parts by weight of polyurethane. More preferably, it is 300 to 450 parts by weight. If the content of the non-aqueous solvent and the electrolyte is less than 200 parts by weight, the ion conductivity may be insufficient and the charge / discharge capacity as a battery may be reduced. In addition, transparency may be lost. On the other hand, if it exceeds 500 parts by weight, the mechanical strength of the gel ion conductor may be lowered.

The electrolyte contained in the gel ion conductor is not particularly limited as long as it is a known one. For example, lithium salts such as LiClO ₄ , LiBF ₄ , LiPF ₆ , LiAsF ₆ which are inorganic compounds, potassium salts such as KClO ₄ , KBF ₄ , KPF ₆ , KAsF ₆ , NaClO ₄ , NaBF ₄ , NaPF ₆ , NaAsF ₆ etc. Sodium salt, CF ₃ SO ₃ Li, (CF ₃ SO ₂ ) ₂ NLi, (CF ₃ SO ₂ ) ₃ CLi and other organic fluorine lithium salts, tetramethylammonium tetrafluoroborate, tetraethylammonium hexafluorophosphate And quaternary ammonium salts such as tetrabutylammonium tetrafluoroborate and monomethyltriethylammonium tetrafluoroborate. These electrolytes may be appropriately selected in consideration of the use of the electrochemical device, the solubility in the non-aqueous solvent to be used, the conductivity in the electrolytic solution, and the like.

  The concentration of the electrolyte in the non-aqueous solvent is not particularly limited, but is preferably 0.1 to 15 mol / l. More preferably, it is 0.1-5 mol / l.

  The thickness of the gel ion conductor varies depending on the use of the electrochemical device, but is preferably 1 mm or less. More preferably, it is 0.001-0.5 mm, and 0.001-0.3 mm is especially preferable. If the thickness is less than 0.001 mm, coating may be difficult. On the other hand, if it exceeds 1 mm, sufficient electrical performance may not be obtained.

  As a method for producing the gel-like ionic conductor of the present invention, once the polyurethane is made, the method is made to swell by immersing the electrolyte in a non-aqueous solvent, and in the non-aqueous solvent in which the electrolyte is dissolved. The method of making a polyol and isocyanate react is mentioned. Among these, the latter method is preferable from the viewpoint that the shape of the gel can be freely controlled and can be easily prepared. After the composition of the electrochemical device other than the gel ion conductor is prepared, a solution in which a polyol and an isocyanate are dissolved in a non-aqueous solvent in which an electrolyte is dissolved is injected into the device, and the gel is formed by heat treatment. When it produces | generates, there exists an advantage that the adhesiveness of a gel and a structure can be improved.

  The gel-like ionic conductor according to the present invention can be used in various electrochemical devices. For example, a lithium ion secondary battery, a wet photovoltaic cell, a capacitor, an electric double layer capacitor and the like can be mentioned. Further, it can be expected to be used as a light control material such as a light control glass using an electrochromic phenomenon that causes a change in color tone by applying a voltage, a material for a new recording medium applying the principle of photoelectrochemistry, and the like.

  Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto.

  First, the evaluation method of the gel-like ionic conductor produced by the Example and the comparative example is demonstrated.

(Mechanical strength)
The state when the gel-like ionic conductor having a size of 4 cm × 4 cm and a thickness of 0.5 mm is bent is judged by visual observation and evaluated as follows.
○: Even if bent 180 degrees, no tearing occurs, and elasticity is restored to its original shape.
X: Tears when bent 180 degrees.

(Electrolytic solution retention)
The electrolyte solution retention is determined by the presence or absence of bleeding. Specifically, since the bleeding of the electrolytic solution occurs so as to ooze from the gel surface, it is evaluated as follows based on visual judgment.
○: Cured and no bleed ×: Cured but with or without bleed

(Total light transmittance, haze)
The total light transmittance and haze of the gel ion conductor are measured with a haze meter HM-150 (manufactured by Murakami Color Research Laboratory). As for the measurement conditions, transmission is measured according to JIS K7361, and haze is measured according to JIS K7136.

(Ionic conductivity)
A gel-like ionic conductor is sandwiched between stainless plates to produce a measurement cell. The resistance component is measured by applying an AC voltage between the electrodes of the cell at 25 ° C. (using an AC impedance method). Ion conductivity is calculated from the real impedance intercept of the Cole-Cole plot.

Example 1
In a glass container containing 400 parts by weight of a LiPF ₆ propylene carbonate (PC) solution prepared to 1 mol / l, a polycaprolactone diol having a molecular weight of 2,000 (manufactured by Daicel Chemical Industries: Plaxel L-220AL, hydroxyl value = 56. (5 mg KOH / g) 84.4 parts by weight, isocyanurate-modified polyisocyanate (manufactured by Asahi Kasei Chemicals: Duranate TPA-100, NCO concentration 23.1% by weight) was added 15.6 parts by weight and mixed well. Further, an appropriate amount of an organic zirconia compound (manufactured by Matsumoto Fine Chemicals Co., Ltd .: ORGATIZ ZC-700) as a polymerization catalyst was added to obtain a uniform compounded liquid. The mixture was degassed under reduced pressure, and then poured into a mold on a 100 μm-thick polyethylene terephthalate release film treated with silicon (inside mold dimensions: 4 cm × 4 cm × 0.5 mm). A gel-like ionic conductor was obtained by allowing the compounded solution in the mold to reach 60 ° C. and allowing it to stand.

The obtained gel ion conductor was cured and no bleed occurred (◯). Moreover, when it was bent 180 degrees, it returned to the original shape without tearing (◯). The total light transmittance of the gel ion conductor was 93%, and the haze was 0.4%. The ionic conductivity at 25 ° C. was 2.0 × 10 ⁻³ S / cm.

(Example 2)
A gel ion conductor was obtained in the same manner as in Example 1 except that the PC solution of LiPF ₆ prepared at 1 mol / l was changed to 300 parts by weight.
The obtained gel ion conductor was cured and no bleed occurred (◯).
Moreover, when it was bent 180 degrees, it returned to its original shape without tearing (◯). The total light transmittance of the gel ion conductor was 93%, and the haze was 0.4%. The ionic conductivity at 25 ° C. was 1.0 × 10 ⁻³ S / cm.

(Example 3)
A gel ion conductor was obtained in the same manner as in Example 1 except that the PC solution of LiPF ₆ prepared at 1 mol / l was changed to 233 parts by weight.
The obtained gel ion conductor was cured and no bleed occurred (◯). Moreover, when it was bent 180 degrees, it returned to the original shape without tearing (◯). The total light transmittance of the gel ion conductor was 93%, and the haze was 0.4%. The ionic conductivity at 25 ° C. was 5.0 × 10 ⁻⁴ S / cm.

Example 4
A gel ion conductor was obtained in the same manner as in Example 1 except that the electrolytic solution was changed to a PC solution of KPF ₆ prepared at 1 mol / l.
The obtained gel ion conductor was cured and no bleed occurred (◯). Moreover, when it was bent 180 degrees, it returned to the original shape without tearing (◯). The total light transmittance of the gel ion conductor was 93%, and the haze was 0.4%. The ionic conductivity at 25 ° C. was 1.0 × 10 ⁻³ S / cm.

(Example 5)
A gel ion conductor was obtained in the same manner as in Example 2 except that the electrolytic solution was changed to a PC solution of KPF ₆ prepared at 1 mol / l.
The obtained gel ion conductor was cured and no bleed occurred (◯).
Moreover, when it was bent 180 degrees, it returned to the original shape without tearing (◯). The total light transmittance of the gel ion conductor was 93%, and the haze was 0.4%. The ionic conductivity at 25 ° C. was 8.0 × 10 ⁻⁴ S / cm.

(Example 6)
84.4 parts by weight of a polycaprolactone diol having a molecular weight of 2,000 is added to 78.7 parts by weight of a polycaprolactone triol having a molecular weight of 2,000 (manufactured by Daicel Chemical Industries: Plaxel L-320AL, hydroxyl value = 83.4 mgKOH / g). A gel ion conductor was obtained in the same manner as in Example 1 except that the amount of the nurate-modified polyisocyanate was changed from 15.6 parts by weight to 21.3 parts by weight.
The obtained gel ion conductor was cured and no bleed occurred (◯).
Moreover, when it was bent 180 degrees, it returned to its original shape without tearing (◯). The total light transmittance of the gel ion conductor was 93%, and the haze was 0.4%. The ionic conductivity at 25 ° C. was 2.0 × 10 ⁻³ S / cm.

(Example 7)
A gel ion conductor was obtained in the same manner as in Example 6 except that the PC solution of LiPF ₆ prepared to 1 mol / l was changed to 300 parts by weight.
The obtained gel ion conductor was cured and no bleed occurred (◯).
Moreover, when it was bent 180 degrees, it returned to its original shape without tearing (◯). The total light transmittance of the gel ion conductor was 93%, and the haze was 0.4%. The ionic conductivity at 25 ° C. was 9.0 × 10 ⁻⁴ S / cm.

(Comparative Example 1)
73.7 parts by weight of a polypropylene glycol having a molecular weight of 1,000 (manufactured by NOF Corporation: Uniol D-1000, hydroxyl value = 110 mgKOH / g) was used as the polyol component, and 26.3 parts by weight of the isocyanurate-modified polyisocyanate was used. Except for this, the operation was carried out in the same manner as in Example 1, but the blended solution was not cured and a gel-like ionic conductor could not be obtained.

(Comparative Example 2)
100 parts by weight of a PC solution of LiPF ₆ prepared to 1 mol / l, 73.7 parts by weight of polypropylene glycol having a molecular weight of 1,000 as a polyol component (manufactured by NOF Corporation: Uniol D-1000, hydroxyl value = 110 mgKOH / g), A gel-like ionic conductor was obtained in the same manner as in Example 1 except that 26.3 parts by weight of isocyanurate-modified polyisocyanate was used.
The obtained gel ion conductor was cured and no bleed occurred (◯). Moreover, when it bent 180 degree | times, it was torn (x). The total light transmittance of the gel ion conductor was 93%, and the haze was 0.4%. The ionic conductivity at 25 ° C. was 1.0 × 10 ⁻⁴ S / cm.

(Comparative Example 3)
Polypropylene glycol having a molecular weight of 2,000 (manufactured by NOF Corporation: Uniol D-2000, hydroxyl value = 55.4 mgKOH / g) is used as the polyol component, 84.8 parts by weight, and 15.2 parts by weight of the isocyanurate-modified polyisocyanate. Except that it was changed to, the operation was performed in the same manner as in Example 1, but the compounded liquid was not cured and a gel ion conductor could not be obtained.
The results of Examples 1 to 3 and Comparative Examples 1 to 3 are summarized in Table 1.

L-220AL: Polycaprolactone diol (Daicel Chemical Industries: Plaxel L-220AL)
L-320AL: Polycaprolactone triol (Daicel Chemical Industries: Plaxel L-320AL)
D-1000: Polypropylene glycol (manufactured by NOF Corporation: UNIOR D-1000)
D-2000: Polypropylene glycol (manufactured by NOF Corporation: UNIOR D-2000)
TPA-100: Isocyanurate-modified polyisocyanate (Asahi Kasei Chemicals Corporation: Duranate TPA-100)
1M LiPF ₆ / PC: Propylene carbonate solution of LiPF ₆ adjusted to 1 mol / l 1M KPF ₆ / PC: Propylene carbonate solution of KPF ₆ adjusted to 1 mol / l

  The results of Comparative Examples 1 to 3 are considered to be because the gel-like ionic conductor was not prepared within the range defined by the present invention. That is, a polycaprolactone polyol having at least two hydroxyl groups in the molecule and a compound having at least two isocyanate groups in the molecule (provided that any one of the hydroxyl groups and the isocyanate groups is at least three) is crosslinked. This is considered to be caused by not being obtained by reaction.

Claims (8)

  A gel-like ionic conductor comprising a polyurethane as a gel matrix material, a non-aqueous solvent, and an electrolyte, wherein the polyurethane is a polycaprolactone polyol having at least two hydroxyl groups in the molecule and at least 2 in the molecule. A gel-like ionic conductor characterized by having a crosslinked structure derived from a compound having one or more isocyanate groups (provided that any one of the hydroxyl groups and isocyanate groups is at least three).   The gel ion conductor according to claim 1, wherein the polycaprolactone polyol having at least two hydroxyl groups in the molecule is polycaprolactone diol or polycaprolactone triol. The compound having at least two or more isocyanate groups in the molecule is represented by the following formula:
(In the formula, R ^{1 to} R ³ are the same or different alkylene groups having 1 to 8 carbon atoms.)
The gel ion conductor according to claim 1 or 2, which is a compound represented by the formula:   The gel-like ionic conductor according to any one of claims 1 to 3, wherein the total amount of the non-aqueous solvent and the electrolyte is included in an amount of 200 to 500 parts by weight with respect to 100 parts by weight of polyurethane as a matrix material of the gel. .   The gel ion conductor according to any one of claims 1 to 4, wherein the electrolyte is contained in the non-aqueous solvent at a concentration of 0.1 to 15 mol / l.   The non-aqueous solvent is at least one aprotic solvent selected from the group consisting of a carbonate ester, a lactone compound, a sulfolane compound, a lactam compound, and a phosphate compound. Gel-like ionic conductor as described in one.   The gel electrolyte according to any one of claims 1 to 6, wherein the electrolyte is at least one electrolyte selected from a lithium salt and a potassium salt.   In a non-aqueous solvent containing an electrolyte, a polycaprolactone polyol having at least two hydroxyl groups in the molecule and a compound having at least two isocyanate groups in the molecule (provided that at least one of the hydroxyl group and the isocyanate group is at least A method for producing a gel-like ionic conductor, comprising obtaining a gel-like ionic conductor by cross-linking reaction of three or more).