JP2006310071A - Solid electrolyte and lithium polymer battery using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid electrolyte excellent in battery property (conductivity, charging/discharging property or the like), and a lithium polymer battery using the same. <P>SOLUTION: The solid electrolyte is made of cured film obtained from a lithium ion conductive composition [1] containing curing oligomer (A), electrolyte salt (B), ionic liquid (C). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a solid electrolyte excellent in battery performance (conductivity, charge / discharge characteristics, etc.) and a lithium polymer battery using the solid electrolyte.

  In recent years, portable terminals such as notebook personal computers, mobile phones, and PDAs have become widespread, and such portable terminals have been rapidly reduced in size, thickness, weight, and performance in search of more comfortable portability. . In addition, lithium secondary batteries are frequently used as the secondary battery for the power source of such portable terminals. Similarly, the demand for smaller, thinner, lighter, higher performance is also increasing for batteries. Yes.

Under these demands, sheet-type secondary batteries using a solid polymer electrolyte as a thin, high energy density battery are being developed. Secondary batteries using a solid polymer electrolyte are liquid leakage. Therefore, it has many features not found in conventional cylindrical and prismatic batteries, such as high reliability, freedom of shape, large area, and extremely thin shape.
Conventionally, as a resin used for an electrolyte, a polyether copolymer having an alkylene oxide group has been known (see, for example, Patent Document 1). In addition, a solid polymer electrolyte comprising a matrix component of a crosslinked polymer containing a urethane (meth) acrylate compound and a polymerizable monomer having a specific structure and an electrolyte salt has been proposed (see, for example, Patent Document 2). ).
JP-A-9-324114 JP 2002-216845 A

However, in the technique disclosed in Patent Document 1, it is necessary to form a film by dissolving it in an organic solvent, drying it, and then bonding it to the negative electrode as an electrolyte film. As a result, the film strength was insufficient. In addition, when the electrolyte resin is applied to a negative electrode, particularly a lithium foil, since the resin is solvent-based, there is a problem that the solvent reacts with lithium of the negative electrode to cause damage and reduce battery performance. There was a limit to thinning with a coating method using a solvent. Furthermore, when the solid electrolyte manufacturing raw material having a solvent is directly applied to the composite positive electrode, the composite positive electrode is partially dissolved and swollen, which may deteriorate the electrode performance.
The disclosed technique of Patent Document 2 is useful as a method that does not use a solvent for the electrolyte, and has good battery performance. However, further improvement is required for recent high demanded performance.
Therefore, in the present invention, a solid electrolyte excellent in battery performance (conductivity, charge / discharge characteristics, etc.) and a lithium polymer battery using the same formed without using a solvent in the electrolyte is provided under such a background. For the purpose.

However, as a result of intensive studies in view of such circumstances, the present inventors obtained from a lithium ion conductive composition [I] containing a curable oligomer (A), an electrolyte salt (B) and an ionic liquid (C). The present invention was completed by finding that a solid electrolyte composed of a cured coating obtained meets the above-mentioned purpose.
The present invention also provides a lithium polymer battery in which the solid electrolyte obtained by the present invention is sandwiched between a positive electrode and a negative electrode.

  The solid electrolyte of the present invention comprises a curable oligomer (A), an electrolyte salt (B) and an ionic liquid (C), more preferably an ethylenically unsaturated monomer (D), an inorganic filler (E), an electrolytic solution (F ) Containing lithium ion conductive composition [I], it has a high ionic conductivity and no charge / discharge characteristics (no deterioration due to repeated charge / discharge) without causing liquid leakage. In particular, it is very useful as a secondary battery, particularly as a lithium polymer secondary battery.

  The present invention is a solid electrolyte comprising a cured film obtained from a lithium ion conductive composition [I], and the lithium ion conductive composition [I] includes a curable oligomer (A), an electrolyte salt (B), and It is a composition comprising an ionic liquid (C), preferably further comprising an ethylenically unsaturated monomer (D) and an inorganic filler (E), and if necessary, an electrolyte solution (F). It is the composition formed.

  Examples of the curable oligomer (A) include epoxy (meth) acrylate, polyester (meth) acrylate, etc., but thinning, conductivity, stability with lithium metal, withstand voltage of 3.5 V or more, more preferably From the standpoint that 4V or more is required, etc., the urethane (meth) acrylate compound (A1) and / or at least one of the molecular terminals is a (meth) acryloyl group and the remaining molecular terminals are all (meth) acryloyl groups. Is preferably a polyisocyanate derivative (A2) which is a hydrocarbon.

  The urethane (meth) acrylate compound (A1) is obtained by reacting polyol, polyisocyanate, and hydroxy (meth) acrylate, and any molecular terminal may be a (meth) acryloyl group. Among them, the compound represented by the following general formula (1) is particularly preferable from the viewpoint of conductivity.

ここで、Ｒ₁はポリオールのウレタン結合残基、Ｒ₂はポリイソシアネートのウレタン結合残基、Ｒ₃はヒドロキシ（メタ）アクリレートのウレタン結合残基であり、ｎは１以上の整数である。

Here, R ₁ is a urethane bond residue of polyol, R ₂ is a urethane bond residue of polyisocyanate, R ₃ is a urethane bond residue of hydroxy (meth) acrylate, and n is an integer of 1 or more.

  As a polyol which comprises a urethane (meth) acrylate type compound (A1), it does not specifically limit, For example, ethylene glycol, propylene glycol, butylene glycol, 1, 4- butanediol, 1, 6-hexanediol, neo Polyhydric alcohols such as pentyl glycol, cyclohexanedimethanol, hydrogenated bisphenol A, polycaprolactone, trimethylol ethane, trimethylol propane, polytrimethylol propane, pentaerythritol, polypentaerythritol, sorbitol, mannitol, glycerin, polyglycerin, Diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polybutyl Besides ethylene glycol, polytetramethylene glycol, etc., ethylene oxide, propylene oxide, tetramethylene oxide, ethylene oxide / propylene oxide random or block copolymer, ethylene oxide / tetramethylene oxide random or block copolymer, propylene oxide Polyol / polyether polyol having at least one structure selected from random / block copolymer of ethylene / tetramethylene oxide, random or block copolymer of ethylene oxide / propylene oxide / tetramethylene oxide Of polybasic acids such as maleic anhydride, maleic acid, fumaric acid, itaconic anhydride, itaconic acid, adipic acid and isophthalic acid Some polyester polyol, caprolactone-modified polyols such as caprolactone-modified polytetramethylene polyol, polyolefin polyol, polybutadiene polyol, such as hydrogenated polybutadiene polyols, and the like.

Among them, the molecular weight is 200 to 6000, preferably 500 to 5000, more preferably 800 to 4000, and ethylene oxide, propylene oxide, tetramethylene oxide, ethylene oxide / propylene oxide random or block copolymer, ethylene oxide. / Tetramethylene oxide random or block copolymer, propylene oxide / tetramethylene oxide random or block copolymer, ethylene oxide / propylene oxide / tetramethylene oxide random or block copolymer It is preferable that it is polyether polyol which has. If the molecular weight of the polyol is less than 200, the strength of the formed film is remarkably lowered, and if it exceeds 6000, the conductivity is adversely affected.
When the urethane (meth) acrylate compound (A1) is a compound represented by the general formula (1), a diol is selected as the polyol.

The polyisocyanate constituting the urethane (meth) acrylate compound (A1) is not particularly limited, and examples thereof include aromatic, aliphatic, cycloaliphatic, and alicyclic polyisocyanates. Among them, tolylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, polyphenylmethane polyisocyanate, modified diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tetramethylxylylene diisocyanate Polyisocyanates such as isocyanate, isophorone diisocyanate, norbornene diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane And polyisocyanate trimer compounds, 2-isocyanatoethyl capronate-2,6-diisocyanate, reaction products of these polyisocyanates and polyols, etc. Particularly preferred are diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, 2-isocyanatoethyl capronate-2,6-diisocyanate.
When the urethane (meth) acrylate compound (A1) is a compound represented by the general formula (1), a diisocyanate is selected as the polyisocyanate from among the polyisocyanates.

  Furthermore, the hydroxy (meth) acrylate constituting the urethane (meth) acrylate compound (A1) is not particularly limited, and examples thereof include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxyethylacryloyl phosphate, 4-butylhydroxy (meth) acrylate, 2- (meth) acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3- (meth) Acryloyloxypropyl (meth) acrylate, caprolactone-modified 2-hydroxyethyl (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, ethylene oxide Hydroxy (meth) acrylate, propylene modified hydroxy (meth) acrylate, ethylene oxide-propylene oxide modified hydroxy (meth) acrylate, ethylene oxide-tetramethylene oxide modified hydroxy (meth) acrylate, propylene oxide-tetramethylene oxide modified hydroxy (meta ) Acrylate, etc., among which 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and ethylene oxide-modified hydroxy (meth) acrylate are preferably used.

  About the manufacturing method of the urethane (meth) acrylate type compound (A1) in which all the molecular ends are (meth) acryloyl groups, there is no particular limitation as long as it is a method of reacting polyol, polyisocyanate, and hydroxy (meth) acrylate. A known method is employed. For example, (i) a method in which three components of polyol, polyisocyanate, and hydroxy (meth) acrylate are mixed and reacted together, and (ii) a polyol and polyisocyanate are reacted to form one or more isocyanate groups per molecule. A method of reacting the intermediate with hydroxy (meth) acrylate after forming the urethane isocyanate intermediate to be contained; (iii) containing one or more isocyanate groups per molecule by reacting polyisocyanate with hydroxy (meth) acrylate And a method of reacting the intermediate with a polyol after the urethane (meth) acrylate intermediate is formed.

  In the above reaction, it is also preferable to use a metal catalyst such as dibutyltin dilaurate or an amine catalyst such as 1,8-diazabicyclo [5.4.0] undecene-7 for the purpose of promoting the reaction.

  The polyisocyanate derivative (A2) used in the present invention is obtained by reacting polyisocyanate, hydroxy (meth) acrylate, and a polyalkylene derivative represented by the following general formula (3), and at least one of the molecular terminals is ( Any compound may be used as long as it is a (meth) acryloyl group and the remainder is a hydrocarbon group. Among them, a compound represented by the following general formula (2) is particularly preferable from the viewpoint of conductivity.

ここで、Ｒ₄はポリイソシアネートのウレタン結合残基、Ｒ₅はヒドロキシ（メタ）アクリレートのウレタン結合残基、Ｒ₆は下記一般式（３）で示されるポリアルキレン誘導体のウレタン結合残基であり、ａ、ｂは１以上の整数である。

Here, R ₄ is a urethane bond residue of polyisocyanate, R ₅ is a urethane bond residue of hydroxy (meth) acrylate, and R ₆ is a urethane bond residue of a polyalkylene derivative represented by the following general formula (3). , A and b are integers of 1 or more.

ここで、Ｙはアルキレン基、Ｚは炭化水素基であり、ｐは１以上の整数である。

Here, Y is an alkylene group, Z is a hydrocarbon group, and p is an integer of 1 or more.

  The polyisocyanate constituting the polyisocyanate derivative (A2) is not particularly limited, and examples thereof include the same aromatic, aliphatic, cycloaliphatic, and alicyclic polyisocyanates as described above. Among them, in the case of the compound represented by the above general formula (2), tolylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, polyphenylmethane polyisocyanate, modified diphenylmethane diisocyanate, hydrogenated xylylene diene Isocyanate, xylylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tetramethylxylylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, 1, -Trimer compounds of polyisocyanates such as bis (isocyanatomethyl) cyclohexane, or reaction products of these polyisocyanates and the above polyols (terminal isocyanate group-containing compounds having 3 or more terminal isocyanate groups), 2-isocyanates Examples include ethyl capronate-2,6-diisocyanate. Among these, hexamethylene diisocyanate trimer compound, 2-isocyanatoethyl capronate-2,6 diisocyanate and the like are particularly preferable from the viewpoints of handleability and viscosity.

  It does not specifically limit as hydroxy (meth) acrylate which comprises a polyisocyanate type derivative (A2), The thing similar to said hydroxy (meth) acrylate is mentioned.

  The polyalkylene derivative represented by the general formula (3) constituting the polyisocyanate derivative (A2) is not particularly limited, and examples thereof include diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, polyethylene glycol, and polypropylene. Glycol, polybutylene glycol, polytetramethylene glycol, etc., ethylene oxide, propylene oxide, tetramethylene oxide, ethylene oxide / propylene oxide random or block copolymer, ethylene oxide / tetramethylene oxide random or block copolymer , Random or block copolymer of propylene oxide / tetramethylene oxide, ethylene oxide / propylene oxide / Compound one of the hydroxyl group, such as polyether polyol is substituted with a hydrocarbon group having at least one structure selected from the random or block copolymers of tiger methylene oxide. Such hydrocarbon groups include alkyl groups (methyl group, ethyl group, propyl group, butyl group, etc.), alicyclic alkyl groups (cyclohexyl group, isobornyl group, etc.), aromatic groups (phenyl group, etc.), etc. Among them, an alkyl group is particularly preferable.

  In the present invention, a urethane (meth) acrylate compound (A1) whose molecular terminals are all (meth) acryloyl groups, and a polyisocyanate type whose at least one molecular terminal is a (meth) acryloyl group and the remainder is a hydrocarbon group When the derivative (A2) is used in combination, it is preferable in terms of electrical conductivity and film strength. In such combination, the urethane (meth) acrylate compound (A1) / polyisocyanate derivative (A2) is 90/10 to 40/60. Furthermore, 90/10 to 50/50, particularly 90/10 to 70/30 are preferable.

The electrolyte salt (B) used in the present invention is not particularly limited as long as it is used as a normal electrolyte. For example, LiBR ₄ (R is a phenyl group or an alkyl group), LiPF ₆ , LiSbF ₆ , LiAsF ₆ , LiBF ₄ , LiCIO ₄ , LiCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiC (CF ₃ SO ₂ ) ₃ , LiC ₆ F ₉ SO ₃ , LiC ₈ F ₁₇ SO ₃ , LiAlCl ₄ , lithium tetrakis Examples include [3,5-bis (trifluoromethyl) phenyl] borate alone or as a mixture. Among them, sulfonic acid type anions or imide salt type electrolytes such as LiCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiC (CF ₃ SO ₂ ) ₃ , LiC ₆ F ₉ SO ₃ , LiC ₈ F _l7 SO _3, etc. Are preferably used.

  The ionic liquid (C) used in the present invention is not particularly limited, but an imidazolium compound represented by the following general formula (4) is particularly preferable from the viewpoint of electrochemical reduction resistance.

（式中Ｒ¹及びＲ³は、置換基を有していても良い炭素数１〜２０の炭化水素基を示し、Ｒ²、Ｒ⁴及びＲ⁵は、それぞれ水酸基、アミノ基、ニトロ基、シアノ基、カルボキシル基、エーテル基、もしくはアルデヒド基を有していてもよい炭素数１〜１０の炭化水素基又は水素原子を示し、Ｘは塩素、臭素、ヨウ素、ＢＦ₄ ^-、ＢＦ₃Ｃ₂Ｆ₅ ^-、ＰＦ₆ ^-，ＮＯ₃ ^-、ＣＦ₃ＣＯ₂ ^-、ＣＦ₃ＳＯ₃ ^-、（ＣＦ₃ＳＯ₂）₂Ｎ^-、（ＣＦ₃ＳＯ₂）₃Ｃ^-、（Ｃ₂Ｆ₅ＳＯ₂）₂Ｎ^-、ＡｌＣｌ₄ ^-、Ａｌ₂Ｃｌ₇ ^-のいずれかを示す。）

(Wherein R ¹ and R ³ represent an optionally substituted hydrocarbon group having 1 to 20 carbon atoms, and R ² , R ⁴ and R ⁵ are a hydroxyl group, an amino group, a nitro group, A C1-C10 hydrocarbon group or hydrogen atom which may have a cyano group, a carboxyl group, an ether group, or an aldehyde group, and X represents chlorine, bromine, iodine, BF ₄ ⁻ , BF ₃ C ₂ F ₅ ⁻ , PF ₆ ⁻ , NO ₃ ⁻ , CF ₃ CO ₂ ⁻ , CF ₃ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) ₃ C ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , AlCl ₄ ⁻ , or Al ₂ Cl ₇ ⁻ is indicated.)

Specific examples of the imidazolium compound represented by the general formula (4) include, for example, 1-isopropyl-2,3-dimethylimidazolium bistrifluoromethanesulfonyl salt, 1-ethyl-2,3-dimethylimidazolium bistri Fluoromethanesulfonyl salt, 1-butyl-2,3-dimethylimidazolium bistrifluoromethanesulfonyl salt, 1-hexyl-2,3-dimethylimidazolium bistrifluoromethanesulfonyl salt, 1-octyl-2,3-dimethylimidazolium Examples thereof include bistrifluoromethanesulfonyl salt. Among them, 1-isopropyl-2,3-dimethylimidazolium bistrifluoromethanesulfonyl salt is most preferable from the viewpoint of conductivity and reduction resistance.

〔ここで、Ｒ¹は水素又はメチル基、Ｒ²は水素、炭素数１〜１８の直鎖又は分岐のアルキル基、ｋ、ｌ、ｍはいずれも整数であり、ｋ＋ｌ＋ｍ≧１である。尚、一般式中、括弧内はブロック共重合体又はランダム共重合体のいずれでもよい。〕
炭素数１〜１８の直鎖又は分岐のアルキル基としては、メチル、エチル、ｎ−プロピル、イソプロピル、ｎ−ブチル、イソブチル、ｓｅｃ−ブチル、ｔ−ブチル、ペンチル、ヘキシル、オクチル、ノニル、デシル、ウンデシル、ドデシル、テトラデシル、ヘキサデシル、オクタデシル等が例示される。 Although it does not specifically limit as ethylenically unsaturated monomer (D) used by this invention, It is preferable that it is a polymerizable monomer shown by General formula (5).

[Wherein R ¹ is hydrogen or a methyl group, R ² is hydrogen, a linear or branched alkyl group having 1 to 18 carbon atoms, k, l, and m are all integers, and k + 1 + m ≧ 1. In the general formula, the parenthesis may be a block copolymer or a random copolymer. ]
Examples of the linear or branched alkyl group having 1 to 18 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, pentyl, hexyl, octyl, nonyl, decyl, Examples include undecyl, dodecyl, tetradecyl, hexadecyl, octadecyl and the like.

  In addition to the polymerizable monomer represented by the general formula (5), 2-vinylpyrrolidone, acryloylmorpholine, 2-hydroxybutyl vinyl ether, ethylethylene glycol mono (meth) acrylate, propylethylene glycol mono (meth) Monofunctional monomers such as acrylate, phenylethylene glycol mono (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol Di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate , Ethylene oxide modified bisphenol A type di (meth) acrylate, propylene oxide modified bisphenol A type di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) Bifunctional such as acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, diglycidyl phthalate di (meth) acrylate, hydroxypivalic acid modified neopentyl glycol di (meth) acrylate Monomers, trimethylolpropane tri (meth) acrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, pentaerythritol (Meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, tri (meth) acryloyloxyethoxytrimethylolpropane, glycerin polyglycidyl ether poly (meth) Trifunctional or higher functional monomers such as acrylate are exemplified, and the polymerizable monomer of the general formula (5) is particularly preferable.

Specific examples of the polymerizable monomer represented by the general formula (5) include polyethylene glycol mono (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and polypropylene glycol mono (meth) acrylate. , Polyethylene glycol-polypropylene glycol mono (meth) acrylate, poly (ethylene glycol-tetramethylene glycol) mono (meth) acrylate, poly (propylene glycol-tetramethylene glycol) mono (meth) acrylate, methoxypolyethylene glycol mono (meth) acrylate , Ethoxy polyethylene glycol mono (meth) acrylate, octoxy polyethylene glycol-polypropylene glycol mono (meth) acrylate Lauroxypolyethylene glycol mono (meth) acrylate, stearoxy polyethylene glycol mono (meth) acrylate. Among them, in general formula (4), methoxypolyethylene glycol mono (meth) acrylate in which R ¹ is hydrogen or a methyl group, R ² is a methyl group, k is 3, 9 or 12, 1 is 0, and m is 0 is conductive. Particularly preferable from the viewpoint of rate.

In the present invention, it is preferable to contain an inorganic filler (E) in terms of mechanical strength. Examples of the inorganic filler (E) include silicon oxide, alumina, titanium oxide, zirconia, barium titanate, calcium titanate, and titanic acid. Lead, γ-LiAlO ₂ , LiTiO _{3 and the} like can be mentioned, among which silicon oxide, preferably silicon oxide having hydrophobicity, silicon oxide having hydrophilicity, particularly preferably silicon oxide having hydrophilicity.
As the silicon oxide having hydrophobicity, for example, silicon oxide surface-treated with a silicon compound selected from silicon oil, hexaalkyldisilazane, and alkylsilane may be used, and one kind or two kinds may be used in combination. .

  Specific examples of silicone oil include dimethyl silicone oil, phenylmethyl silicone oil, etc. Specific examples of hexaalkyldisilazane include hexamethyldisilazane, hexaethyldisilazane, etc. Specific examples of alkylsilane include butylsilane, hexyl Specific examples of silicon oxide surface-treated with silicon oil include silane, octylsilane and the like. For example, “RY50”, “NY50”, “RY200S”, “R202”, “RY200” manufactured by Nippon Aerosil Co., Ltd. Specific examples of silicon oxide surface-treated with hexaalkyldisilazane include, for example, “RY50”, “NAX50”, “NX90”, “RX200”, “RX200” manufactured by Nippon Aerosil Co., Ltd. RX300 "," R812 "," R812S Etc., and specific examples of the silicon oxide surface-treated with an alkylsilane, for example, Nippon Aerosil Co., Ltd. "R805", and the like.

Hydrophilic silicon oxide is obtained by hydrolyzing silicon tetrachloride as a raw material in an oxygen / hydrogen flame. Silanol groups (≡SiOH) are present on the surface of silicon oxide particles. Is something that exists. Specific examples include “Aerosil 300”, “Aerosil 200”, “Aerosil 100”, “Aerosil 50” manufactured by Nippon Aerosil Co., Ltd., and the like.
In the present invention, the inorganic filler (E) is preferably fine particles, and the particle size is preferably 1 μm or less from the viewpoint of improving mechanical strength. A more preferable particle size is 7 to 500 nm, particularly 7 to 40 nm.

  In the present invention, an electrolytic solution (F) can be further used to improve conductivity. Examples of the electrolytic solution (F) include carbonate solvents (propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate). ), Amide solvents (N-methylformamide, N-ethylformamide, N, N-dimethylformamide, N-methylacetamide, N-ethylacetamide, N-methylpyrrolidinone), lactone solvents (γ-butyllactone, γ- Valerolactone, δ-valerolactone, 3-methyl-1,3oxazolidine-2-one, etc.), alcohol solvent (ethylene glycol, propylene glycol, glycerin, methyl cellosolve, 1,2 butanediol, 1,3 butanediol, 1 , 4 butanezio , Diglycerin, polyoxyalkylene glycol cyclohexanediol, xylene glycol, etc.), ether solvent (methylal, 1,2-dimethoxyethane, 1,2-diethoxyethane, 1-ethoxy-2-methoxyethane, alkoxy polyalkylene ether, etc. ), Nitrile solvents (benzonitrile, acetonitrile, 3-methoxypropionitrile, etc.), phosphoric acids and phosphoric ester solvents (regular phosphoric acid, metaphosphoric acid, pyrophosphoric acid, polyphosphoric acid, phosphorous acid, trimethyl phosphate, etc.), 2-imidazolid Nons (1,3-dimethyl-2-imidazolidinone, etc.), pyrrolidones, sulfolane solvents (sulfolane, tetramethylene sulfolane), furan solvents (tetrahydrofuran, 2-methyltetrahydrofuran, 2,5-dimethoxytetrahydrofuran) Dioxolane, dioxane, and the like, these alone or a mixed solvent can be used. Of these, carbonates, ethers and furan solvents are preferred.

  Thus, in the present invention, the curable oligomer (A), the electrolyte salt (B) and the ionic liquid (C), preferably further containing an ethylenically unsaturated monomer (D) and an inorganic filler (E) are necessary. Accordingly, a composition containing the electrolytic solution (F) is also obtained, and the content of each component is as follows.

Regarding the electrolyte salt (B), the ratio of the number of moles of lithium atoms and etheric oxygen atoms in the lithium ion conductive composition [I] is preferably 0.02 to 0.2, more preferably. It is 0.03-0.1, and it becomes unfavorable for conductivity outside the above range.
The ionic liquid (C) is preferably 40 to 900 parts by weight, particularly 100 to 900 parts by weight, more preferably 150 to 900 parts by weight, with respect to 100 parts by weight of the curable oligomer (A). If the amount is less than parts by weight, the conductivity is not improved. If the amount exceeds 900 parts by weight, the mechanical strength of the film is significantly lowered, which is not preferable.
The ethylenically unsaturated monomer (D) is preferably 10 to 100 parts by weight, particularly 10 to 70 parts by weight, more preferably 10 to 30 parts by weight, based on 100 parts by weight of the curable oligomer (A). If the amount is less than 10 parts by weight, the effect is not recognized.

  In addition, the content of the indefinite filler (E) is about 100 parts by weight of the curable oligomer (A) (when the ethylenically unsaturated monomer (D) is contained, the curable oligomer (A) and the ethylenically unsaturated monomer (D) ) To 100 to 100 parts by weight, more preferably 3 to 50 parts by weight, particularly preferably 10 to 50 parts by weight, and further preferably 20 to 50 parts by weight. If the inorganic filler (E) is less than 0.5 parts by weight, it is inferior in terms of improving the mechanical strength and heat resistance.

  The preferable composition when using the electrolytic solution (F) is not particularly limited, but 100 parts by weight of the curable oligomer (A) (when the ethylenically unsaturated monomer (D) is contained, the curable oligomer (A) and ethylene are used. 10 to 100 parts by weight, more preferably 10 to 70 parts by weight, particularly preferably 10 to 30 parts by weight, and the effect is less than 10 parts by weight. If it exceeds 100 parts by weight, the strength is insufficient, which is not preferable.

  Thus, in the present invention, the lithium ion conductive composition [I] obtained above is used to form a cured film and become a solid electrolyte.

  The thickness of the cured film obtained from the lithium ion conductive composition [I] is preferably about 5 to 100 μm, more preferably 10 to 40 μm. If the thickness of the cured film is less than 5 μm, the followability is poor, and if it exceeds 100 μm, the conductivity is affected, which is not preferable.

  The lithium ion conductive cured film obtained from the lithium ion conductive composition [I] is preferably formed “directly” on the negative electrode made of lithium foil. Here, “directly formed” means that since the lithium ion conductive composition [I] does not contain a solvent, it is formed by directly applying and curing on a negative electrode made of a lithium foil. Means. Thus, by using the lithium ion conductive composition [I] that does not contain a solvent, the lithium ion conductive cured film is directly formed on the negative electrode made of lithium foil, so that sufficient strength can be obtained even if the film is thin. As a result, the battery performance can be improved, and further, the oxidation of the lithium metal surface can be prevented, and the handling becomes easy.

  Here, in this invention, 10-500 micrometers is preferable, as for the thickness of the lithium foil used for the negative electrode of a lithium polymer battery, 50-200 micrometers is especially preferable, Furthermore, 50-150 micrometers is preferable. A lithium ion conductive cured coating is applied on the surface of a lithium foil fixed on a current collector such as copper foil or iron foil.

Formation of a lithium ion conductive cured film according to the present invention is achieved by coating a negative electrode such as a lithium foil with the lithium ion conductive composition [I], and then polymerizing and curing by irradiation with actinic rays or / and heat. The In the present invention, it is preferable to polymerize and cure by irradiation with actinic rays in view of handling and production efficiency.
Moreover, it is also preferable to heat after irradiating actinic rays to accelerate curing.

Actinic ray irradiation is usually performed by light, ultraviolet rays, electron beams, X-rays, etc. Among them, ultraviolet rays are preferable, and in the case of ultraviolet irradiation, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp are used as a light source. Chemical lamps and the like are used. The amount of irradiation is appropriately selected without particular limitation, 100~1000mJ / cm ^2, preferably in integrated irradiation dose of 100~700mJ / cm ^2, it is preferable to perform irradiation.
When polymerizing and curing by irradiation with these actinic rays, the photopolymerization initiator is a polymerizable component of the lithium ion conductive composition [I] [curable oligomer (A) and ethylenically unsaturated monomer (D). It is preferable to contain 0.3 part by weight or more, particularly 0.5 to 5 parts by weight with respect to 100 parts by weight. When both the integrated irradiation amount and the photopolymerization initiator are small, the strength of the film cannot be maintained, and when the amount is too large, no further effect is observed, which is not preferable.

  The photopolymerization initiator is not particularly limited, and a known photopolymerization initiator can be used, and examples thereof include benzophenone, P, P′-bis (dimethylamino) benzophenone, P, P′-bis (diethylamino). ) Benzophenone, P, P'-bis (dibutylamino) benzophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin phenyl ether, benzoin isobutyl ether, benzoylbenzoic acid, benzoylbenzoic acid methyl , Benzyldiphenyl disulfide, benzyldimethyl ketal, dibenzyl, diacetyl, anthraquinone, naphthoquinone, 3,3′-dimethyl-4-methoxybenzophenone, dichloroacetophenone, 2- Chlorothioxanthone, 2-methylthioxanthone, 2,4-diethylthioxanthone, 2,2-diethoxyacetophenone, 2,2-dichloro-4-phenoxyacetophenone, phenylglyoxylate, α-hydroxyisobutylphenone, dibenzoparone, 1- (4-Isopropylphenyl) -2-hydroxy-2-methyl-1-propanone, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, tribromophenylsulfone, tribromomethylphenylsulfone Methylbenzoylformate, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,2-dimethoxy-1,2-diphenylmethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, and Are 2, 4, -[Tris (trichloromethyl)]-1,3,5-triazine, 2,4- [bis (trichloromethyl)]-6- (4'-methoxyphenyl) -1,3,5-triazine, 2,4 -[Bis (trichloromethyl)]-6- (4'-methoxynaphthyl) -1,3,5-triazine, 2,4- [bis (trichloromethyl)]-6- (piperonyl) -1,3,5 A triazine, a triazine derivative such as 2,4- [bis (trichloromethyl)]-6- (4′-methoxystyryl) -1,3,5-triazine, an acridine derivative such as acridine and 9-phenylacridine, 2′-bis (o-chlorophenyl) -4,5,4 ′, 5′-tetraphenyl-1,2′-biimidazole, 2,2′-bis (o-chlorophenyl) -4,5,4 ′, 5′-tetraphenyl-1, '-Biimidazole, 2,2'-bis (o-fluorophenyl) -4,5,4', 5'-tetraphenyl-1,1'-biimidazole, 2,2'-bis (o-methoxyphenyl) ) -4,5,4 ′, 5′-tetraphenyl-1,1′-biimidazole, 2,2′-bis (p-methoxyphenyl) -4,5,4 ′, 5′-tetraphenyl-1 , 1′-biimidazole, 2,4,2 ′, 4′-bis [bi (p-methoxyphenyl)]-5,5′-diphenyl-1,1′-biimidazole, 2,2′-bis ( 2,4-dimethoxyphenyl) -4,5,4 ′, 5′-diphenyl-1,1′-biimidazole, 2,2′-bis (p-methylthiophenyl) -4,5,4 ′, 5 ′ -Diphenyl-1,1'-biimidazole, bis (2,4,5-triphenyl) -1,1'-biimidazole, etc. Hexaarylbiimidazole derivatives such as tautomers covalently bonded at 1,2′-, 1,4′-, 2,4′-, disclosed in JP-A-45-37377, triphenylphosphine, and others Also includes 2-benzoyl-2-dimethylamino-1- [4-morpholinophenyl] -butane, and particularly 2-hydroxy-2-methyl-1-phenylpropan-1-one in view of handling. 2,2-dimethoxy-1,2-diphenylmethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone and the like are particularly suitable.

  Moreover, when making it superpose | polymerize and cure with a heat | fever, a thermal-polymerization initiator uses the polymeric component [curable oligomer (A) and ethylenically unsaturated monomer (D)] 100 of lithium ion conductive composition [I]. It is preferable to contain 0.1-5 weight part with respect to a weight part, especially 0.3-1 weight part.

The thermal polymerization initiator is not particularly limited, and examples thereof include azobisisobutyronitrile, benzoyl peroxide, lauroyl peroxide, ethyl methyl ketone peroxide, bis- (4-t-butylcyclohexyl) peroxydicarbonate, and diisopropyl. Examples include peroxydicarbonates such as peroxydicarbonate.
Moreover, when it superposes | polymerizes and hardens using light and a heat together, it is preferable to use said photoinitiator and said thermal polymerization initiator together.

  Furthermore, in the present invention, a sensitizer, a storage stabilizer and the like are used in combination as necessary. As the sensitizer, urea, a nitrile compound (N, N-disubstituted-P-aminobenzonitrile, etc.) and a phosphorus compound (tri-n-butylphosphine, etc.) are preferable. As the storage stabilizer, quaternary ammonium is used. Chloride, benzothiazole and hydroquinone are preferred.

Thus, the lithium ion conductive cured film has a very excellent mechanical strength despite being very thin, and is a lithium ion battery (primary battery) excellent in battery performance such as conductivity and charge / discharge characteristics. , A secondary battery). In particular, when applied to a secondary battery, a great effect is shown.
Furthermore, in the present invention, when the inorganic filler (E), particularly fine particles of silicon oxide having hydrophilicity, are blended with the lithium ion conductive composition [I], the solid state is not reduced without causing a decrease in ion conductivity. The mechanical strength and heat resistance of the electrolyte membrane can be further increased, and there is also a function of suppressing a short circuit between the electrodes. Furthermore, since it is excellent in equipment characteristics in a high temperature range, it exhibits an excellent effect in high temperature stability.

The solid electrolyte of the present invention is basically sandwiched between a positive electrode, in particular, a composite positive electrode and a negative electrode, and becomes a lithium polymer battery. If necessary, a separator is used as a polymer holding material. Also good.
As the separator, one having low resistance to ion migration of the electrolyte solution is used. For example, 1 such as polypropylene, polyethylene, polyester, polytetrafluoroethylene, polyvinyl alcohol, ethylene-vinyl acetate copolymer saponified product, etc. A microporous film, a nonwoven fabric or a woven fabric selected from more than one kind of materials can be mentioned, and a short circuit can be completely prevented. When the solid electrolyte of the present invention itself has a function as a separator, these are unnecessary.

In the present invention, the “composite positive electrode” means a composition comprising a positive electrode active material, a conductive additive such as ketjen black and acetylene black, a binder such as polyvinylidene fluoride, and if necessary, an ion conductive polymer. A positive electrode material mixed with is applied to a conductive metal plate (aluminum foil or the like).
Examples of the positive electrode active material of the lithium polymer battery of the present invention, particularly of the secondary battery, include inorganic active materials, organic active materials, and composites thereof, but inorganic active materials or inorganic active materials and organic active materials can be exemplified. A composite of substances is particularly preferable from the viewpoint of increasing the energy density.

As inorganic-based active material, Li _0.3 MnO ₂ in a _{3V, Li 4 Mn 5 O 12,} V 2 O 5 , _{etc., LiCoO 2, LiMn 2 O 4} , LiNiO metal oxide such as ₂ is 4V-based, TiS _2, MoS ₂ and metal sulfides such as FeS, and complex oxides of these compounds and lithium. Examples of the organic active material include conductive polymers such as polyacetylene, polyaniline, polypyrrole, polythiophene, and polyparaphenylene, (carbon) organic disulfide compounds, sulfur-based positive electrode materials such as carbon disulfide, and active sulfur.

  Examples of the ion conductive polymer include polymers such as polyethylene glycol dialkyl ether such as polyethylene glycol dimethyl ether and polyethylene glycol diethyl ether, polyethylene glycol monoalkyl ether, and polyethylene glycol.

On the other hand, the negative electrode active material of the lithium polymer battery of the present invention includes lithium metal, aluminum, lead, silicon, magnesium, etc. and lithium alloys, polypyridine, polyacetylene, polythiophene, or cation-doped conductive highly conductive materials thereof. Examples include molecules, oxides such as SnO ₂ capable of occluding lithium, and Sn-based alloys. In the present invention, lithium metal is most preferable in terms of energy density.

In the present invention, it is preferable to form a cured film composed of the above lithium ion conductive composition [I] on the negative electrode as described above. However, the above lithium ion conductive composition [ A cured film of I] can also be formed.
In the case of forming such a cured film, the ion conductive polymer is not necessarily required and is appropriately selected.

  Specifically, after applying the above lithium ion conductive composition [I] on the composite positive electrode, it is cured to form a solid electrolyte-positive electrode assembly comprising a lithium ion conductive cured film, It is preferable to join a solid electrolyte-positive electrode assembly and a negative electrode made of lithium foil or the like.

  Furthermore, in the present invention, a solid electrolyte-negative electrode assembly formed by forming a cured film obtained from the lithium ion conductive composition [I] on a negative electrode made of lithium foil or the like, and a lithium ion conductive material on the composite positive electrode. The solid electrolyte-positive electrode assembly formed by forming a cured film obtained from the conductive composition [I] is preferably bonded so that the solid electrolyte surfaces are in contact with each other. Specifically, the positive electrode material is made of a conductive metal. After coating the plate to form a composite positive electrode, the lithium ion conductive composition [I] is applied on the composite positive electrode and cured to form a solid electrolyte-positive electrode assembly comprising a lithium ion conductive cured film. On the other hand, the lithium ion conductive composition [I] was coated on a negative electrode made of lithium foil or the like and cured to form a solid electrolyte-negative electrode assembly made of a lithium ion conductive cured film, and obtained. Solid Electrolyte - anode assembly and the obtained solid electrolyte - it is preferable to join the cathode assembly in contact to each other the solid electrolyte surface.

  The form of the lithium polymer battery of the present invention, particularly the lithium ion polymer secondary battery, is not particularly limited, but can be enclosed in various forms of battery cells such as coins, sheets, and cylinders.

A flow for manufacturing the lithium polymer battery of the present invention is shown in FIG.
First, the lithium ion conductive composition [I] is applied on the Li foil (negative electrode), and then the film is cured by ultraviolet irradiation and / or heating. Next, a composite positive electrode can be bonded to the cured coating to obtain a battery. However, the present invention is not limited to this, and as described above, the lithium ion conductive composition [I] is applied to the composite positive electrode, the film is cured by ultraviolet irradiation and / or heating, and then the negative electrode is cured. The lithium ion conductive composition [I] is applied to each of the negative electrode and the composite positive electrode, and the film is cured by ultraviolet irradiation and / or heating, and then on the negative electrode and the composite positive electrode. A battery can also be obtained by, for example, bonding the cured films of each other.

In addition, in manufacturing the lithium polymer battery according to the present invention, the positive electrode and the negative electrode can be continuously manufactured, and then both electrodes can be continuously bonded. It can be set as a manufacturing method.
As a result, a conventional batch type, for example, a composite positive electrode stored in a roll shape, or a negative electrode is once unwound from a roll shape and cut into a predetermined size, and then a film of a predetermined size to be an electrolyte layer is formed thereon. Compared to the method of laminating and laminating both electrodes, it can be performed on a continuous line from the winding of the composite positive electrode or negative electrode to the application of the electrolyte, curing, and joining of both electrodes. Manufacturing management in each process becomes easy, for example, generation of cracks is eliminated.
When joining the solid electrolyte-negative electrode assembly and the composite positive electrode, joining the solid electrolyte-positive electrode assembly and the negative electrode, or joining the solid electrolyte-positive electrode assembly and the solid electrolyte-negative electrode assembly, it is performed by thermocompression bonding. Is preferred.

Hereinafter, the present invention will be specifically described with reference to examples.
The following were prepared as the curable oligomer (A).
[Urethane acrylate (A1-1)]
After introducing dry air gas into a reaction vessel equipped with a stirrer, a thermometer, a cooling pipe and an air gas introduction pipe, 160 parts of isophorone diisocyanate (Degussa Huls, “VESTANAT IPDI”), ethylene oxide / propylene oxide 755 parts of block polyether polyol (Asahi Denka Kogyo Co., Ltd., “CM-211”, weight average molecular weight of about 2100) was charged and heated to 70 ° C., then 85 parts of 2-hydroxyethyl acrylate, 0.4 parts of hydroquinone monomethyl ether , And 0.1 part of a mixed liquid of dibutyltin dilaurate (manufactured by Tokyo Fine Chemical Co., “LIOI”) was uniformly dropped over 3 hours to carry out the reaction. After completion of the dropwise addition, the reaction was continued for about 5 hours, and then the disappearance of the isocyanate was confirmed by the result of IR measurement to complete the reaction to obtain urethane acrylate (A1-1) (solid content: 99.8%, number average) Molecular weight: 4300).
In addition, said number average molecular weight is measured by GPC measurement (polystyrene standard).

[Urethane acrylate (A1-2)]
After introducing dry air gas into a reaction vessel equipped with a stirrer, thermometer, cooling pipe and air gas inlet pipe, 170 parts of isophorone diisocyanate (Degussa Huls, “VESTANAT IPDI”), ethylene oxide / propylene oxide 741 parts of a random polyether polyol (Asahi Denka Kogyo Co., Ltd., “PR-2008”, weight average molecular weight of about 2000) was charged, heated to 70 ° C., 89 parts of 2-hydroxyethyl acrylate, 0.4 parts of hydroquinone monomethyl ether , And 0.1 part of a mixed liquid of dibutyltin dilaurate (manufactured by Tokyo Fine Chemical Co., “LIOI”) was uniformly dropped over 3 hours to carry out the reaction. After completion of the dropwise addition, the reaction was continued for about 5 hours, and then the disappearance of isocyanate was confirmed by the result of IR measurement to complete the reaction, and urethane acrylate (A1-2) was obtained (solid content: 99.8%, number average) Molecular weight: 2700).

[Urethane acrylate (A1-3)]
After introducing dry air gas into a reaction vessel equipped with a stirrer, thermometer, cooling pipe and air gas introduction pipe, 97 parts of isophorone diisocyanate (Degussa Huls, “VESTANAT IPDI”), ethylene oxide / propylene oxide 870 parts of random polyether polyol (Asahi Denka Kogyo Co., Ltd., “PR-3007”, weight average molecular weight of about 3000) are charged, and after raising the temperature to 70 ° C., 33 parts of 2-hydroxyethyl acrylate, 0.4 parts of hydroquinone monomethyl ether , And 0.1 part of a mixed liquid of dibutyltin dilaurate (manufactured by Tokyo Fine Chemical Co., “LIOI”) was uniformly dropped over 3 hours to carry out the reaction. After completion of the dropwise addition, the reaction was continued for about 5 hours, and then the disappearance of the isocyanate was confirmed by the result of IR measurement to complete the reaction to obtain urethane acrylate (A1-3) (solid content: 99.8%, number average) Molecular weight: 7000).

[Urethane acrylate (A1-4)]
After introducing dry air gas into a reaction vessel equipped with a stirrer, thermometer, cooling pipe and air gas introduction pipe, 72 parts of hexamethylene diisocyanate (Takeda 700, Taketake 700), ethylene oxide / propylene 850 parts of an oxide random polyether polyol (Asahi Denka Kogyo Co., Ltd., “PR-3007”, weight average molecular weight of about 3000) was charged, heated to 70 ° C., and then polyethylene glycol monoacrylate (Nippon Yushi Co., Ltd., “AE-200”). “) 78 parts, hydroquinone monomethyl ether 0.4 part, and dibutyltin dilaurate (Tokyo Fine Chemical Co., Ltd.,“ LIOI ”) 0.1 part mixed liquid was uniformly dropped over 3 hours to carry out the reaction. After completion of the dropwise addition, the reaction was continued for about 5 hours, and then the disappearance of isocyanate was confirmed by the result of IR measurement, and the reaction was terminated to obtain urethane acrylate (A1-4) (solid content: 99.8%, number average) Molecular weight: 6800).

[Polyisocyanate derivative (A2-1)]
After introducing dry air gas into a reaction vessel equipped with a stirrer, thermometer, cooling pipe, and air gas introduction pipe, 177 parts of hexamethylene diisocyanate trimer ("Duranate TPA-100" manufactured by Asahi Kasei Corporation), 634 parts of polyethylene glycol monomethyl ether (Nippon Yushi Co., Ltd., “Uniox M-1000”, weight average molecular weight of about 1000) was charged, heated to 70 ° C., and then polyethylene glycol monoacrylate (Nippon Yushi Co., “AE-400 ”) 189 parts, hydroquinone monomethyl ether 0.4 part, and dibutyltin dilaurate (Tokyo Fine Chemical Co., Ltd.,“ LIOI ”) 0.1 part mixed liquid was uniformly added dropwise over 3 hours to carry out the reaction. After completion of the dropwise addition, the reaction was continued for about 5 hours, and then the disappearance of the isocyanate was confirmed by the result of IR measurement, and the reaction was terminated to obtain a polyisocyanate derivative (A2-1) (solid content: 99.8%, several Average molecular weight: 4000).

The following were prepared as the ionic liquid (C).
1-butyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) imide (C-1)
1-Isopropyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) imide (C-2)
-1-butyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) hexafluorophosphate (C-3)

The following were prepared as the ethylenically unsaturated monomer (D).
・ Methoxypolyethylene glycol monoacrylate (D-1)
・ Polyethylene glycol diacrylate (D-2)

The following were prepared as the inorganic filler (E).
Hydrophilic silicon oxide (particle size: 7 nm) (manufactured by Nippon Aerosil Co., Ltd., “Aerosil 300”) (E-1)
Hydrophilic silicon oxide (particle size 30 nm) (manufactured by Nippon Aerosil Co., Ltd., “Aerosil 50”) (E-2)
Hydrophobic silicon oxide (particle size: 7 nm) (Nippon Aerosil Co., Ltd., “RX300”) (E-3)
The following was prepared as an electrolytic solution (F).
・ Ethylene carbonate (F-1)

Example 1
(1) Production of Solid Electrolyte-Negative Electrode Assembly LiN (CF ₃ SO ₂ ) ₂ (B) (26 parts) was replaced with methoxypolyethylene glycol monoacrylate (D-1) (30 parts), urethane acrylate of Reference Example 1 (A1 -1) (70 parts), 1-butyl-2,3 dimethylimidazolium bis (trifluoromethanesulfonyl) imide (C-1) (200 parts) as an ionic liquid, 1-hydroxy- as a photopolymerization initiator Cyclohexyl-phenyl-ketone (Ciba Specialty Chemicals, “Irgacure 184”; 3 parts) was added and mixed together to prepare a lithium ion conductive composition [I] (photopolymerizable solution).
Next, this is coated on a negative electrode made of a lithium foil having a thickness of 100 μm with a wire bar in the atmosphere, and irradiated with a high-pressure mercury lamp at an irradiation amount of 500 mJ / cm ² to form a cured film having a thickness of 10 μm. A solid electrolyte-negative electrode assembly was prepared.

(2) Preparation of positive electrode 1.0 g of Li _0.33 MnO ₂ powder and 0.15 g of Ketjen black were sufficiently mixed. Next, 0.10 g of a copolymer of ethylene oxide (88 mmol%) and 2- (2-methoxyethoxy) ethyl glycidyl ether (12 mol%) and 0.033 g of LiN (CF ₃ SO ₂ ) ₂ were dissolved in acetonitrile. It was. The acetonitrile solution was added to the mixed powder of Li _0.33 MnO ₂ and Ketjenblack and mixed well in a mortar to obtain a positive electrode slurry. This was applied in the air onto a 20 μm thick aluminum electrolytic foil using a wire bar and dried at 100 ° C. for 15 minutes to produce a composite positive electrode having a thickness of 30 μm.
The obtained positive electrode and the solid electrolyte-negative electrode assembly were bonded together by thermocompression bonding and sealed in a battery cell to produce a lithium polymer battery of the present invention.

The charge / discharge characteristics of the obtained lithium polymer battery were evaluated as follows.
The charge / discharge test was performed by charging from a voltage of 2 mA to 3.5 V with a current of 0.2 mA / cm ² using a charge / discharge measuring device manufactured by Keisoku Center, and after resting for 10 minutes, 0.2 mA / cm ² The battery voltage was discharged to 2 V with current, and this charge / discharge was repeated. At this time, the capacity retention rate (%) at the initial stage and the 100th cycle was measured to evaluate the charge / discharge characteristics.
Further, the conductivity was calculated by AC impedance measurement using “1280Z” manufactured by Solartron, UK and “HS cell” manufactured by Hosen.

Examples 2-8
A lithium polymer battery was prepared and evaluated in the same manner as in Example 1 except that the composition was changed to lithium ion conductive composition [I] (photopolymerizable solution) as shown in Table 1.

Example 9
(1) Production of solid electrolyte-positive electrode assembly 1.0 g of Li _0.33 MnO ₂ powder and 0.15 g of Ketjen black were sufficiently mixed. Next, 0.10 g of a copolymer of ethylene oxide (88 mmol%) and 2- (2-methoxyethoxy) ethyl glycidyl ether (12 mol%) and 0.033 g of LiN (CF ₃ SO ₂ ) ₂ were dissolved in acetonitrile. It was. The acetonitrile solution was added to the mixed powder of Li _0.33 MnO ₂ and Ketjenblack and mixed well in a mortar to obtain a positive electrode slurry. This was applied in the air on a 20 μm thick aluminum electrolytic foil using a wire bar and dried at 100 ° C. for 15 minutes to produce a composite positive electrode having a thickness of 30 μm.
Next, LiN (CF ₃ SO ₂ ) ₂ (B) (26 parts), methoxypolyethylene glycol monoacrylate (D-1) (30 parts), urethane acrylate (A1-1) (70 parts) as an ionic liquid 1-butyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) imide (C-1) (200 parts), 1-hydroxy-cyclohexyl-phenyl-ketone (Ciba Specialty Chemicals) as a photopolymerization initiator "Irgacure 184"; 3 parts), hydrophilic silicon oxide (particle size 30 nm) (manufactured by Nippon Aerosil Co., Ltd., "Aerosil 50") (E-1) 20 parts are added and mixed, and lithium ion conductive composition Preparation [I] (photopolymerizable solution) was applied on a composite positive electrode having a thickness of 30 μm with a wire bar in the atmosphere. Irradiation with irradiation dose 500 mJ / cm ² at a silver lamp, to form a cured coating having a thickness of 10 [mu] m, the solid electrolyte - to produce a positive electrode assembly.
The obtained solid electrolyte-positive electrode assembly and lithium foil (negative electrode) were bonded together by thermocompression bonding and sealed in a battery cell to produce a lithium polymer battery of the present invention.
The obtained lithium polymer battery was evaluated in the same manner as described above.

Example 10
(1) Production of Solid Electrolyte-Negative Electrode Assembly LiN (CF ₃ SO ₂ ) ₂ (B) (5 parts) and LiBF ₄ (B) (10 parts) were converted into methoxypolyethylene glycol monoacrylate (D-1) ( 37 parts), urethane acrylate (A1-1) (80 parts), 1-butyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) as an ionic liquid were added to 28.1 parts of the solution. ) Imido (C-1) (300 parts), 1-hydroxy-cyclohexyl-phenyl-ketone (Ciba Specialty Chemicals, "Irgacure 184"; 3 parts) as a photopolymerization initiator, hydrophilic oxidation Silicon (particle size 30 nm) (“Aerosil 50” manufactured by Nippon Aerosil Co., Ltd.) (E-1) 10 parts was added and mixed, and the lithium ion conductive composition [I] (Photopolymerizable solution) was prepared, applied to a negative electrode made of a lithium foil having a thickness of 100 μm with a wire bar in the atmosphere, and irradiated with a high-pressure mercury lamp at an irradiation amount of 500 mJ / cm ² to obtain a thickness. A 10 μm cured film was formed to produce a solid electrolyte-negative electrode assembly.

(2) Production of solid electrolyte-positive electrode assembly 1.0 g of Li _0.33 MnO ₂ powder and 0.15 g of Ketjen black were sufficiently mixed. Next, 0.10 g of a copolymer of ethylene oxide (88 mmol%) and 2- (2-methoxyethoxy) ethyl glycidyl ether (12 mol%) and 0.033 g of LiN (CF ₃ SO ₂ ) ₂ were dissolved in acetonitrile. It was. The acetonitrile solution was added to the mixed powder of Li _0.33 MnO ₂ and Ketjenblack and mixed well in a mortar to obtain a positive electrode slurry. This was applied in the air on a 20 μm thick aluminum electrolytic foil using a wire bar and dried at 100 ° C. for 15 minutes to produce a composite positive electrode having a thickness of 30 μm.
Next, LiN (CF ₃ SO ₂ ) ₂ (B) (26 parts)), methoxypolyethylene glycol monoacrylate (D-1) (30 parts), urethane acrylate (A1-1) (70 parts), ionic liquid 1-butyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) imide (C-1) (200 parts) as a photopolymerization initiator, 1-hydroxy-cyclohexyl-phenyl-ketone (Ciba Specialty) Chemicals, "Irgacure 184"; 3 parts), hydrophilic silicon oxide (particle size 30 nm) (Nippon Aerosil Co., Ltd., "Aerosil 50") (E-1) 30 parts are added, mixed and dissolved, Lithium ion conductive composition [I] (photopolymerizable solution) was prepared, and this was applied to a composite positive electrode having a thickness of 30 μm with a wire bar in the air. And cloth, irradiated at dose 500 mJ / cm ² using a high-pressure mercury lamp, to form a cured coating having a thickness of 10 [mu] m, the solid electrolyte - to produce a positive electrode assembly.
The obtained solid electrolyte-negative electrode assembly and solid electrolyte-positive electrode assembly were bonded together by thermocompression bonding and sealed in a battery cell to produce a lithium polymer battery of the present invention.
The obtained lithium polymer battery was evaluated in the same manner as described above.

Comparative Example 1
In Example 1, the same procedure was performed except that 1-butyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) imide as the ionic liquid (C) was not blended to produce a lithium polymer battery. Was evaluated.
Table 1 shows the evaluation results of Examples and Comparative Examples.

  The solid electrolyte of the present invention and a lithium polymer battery using the same have high ion conductivity without causing liquid leakage and the like, and have excellent effects on charge / discharge characteristics (no deterioration due to repeated charge / discharge) In particular, it is very useful as a secondary battery, particularly as a lithium ion polymer secondary battery.

The flow of battery creation is shown.

Claims (9)

A solid electrolyte comprising a cured film obtained from a lithium ion conductive composition [I] containing a curable oligomer (A), an electrolyte salt (B) and an ionic liquid (C). The solid electrolyte according to claim 1, wherein the lithium ion conductive composition [I] further contains an ethylenically unsaturated monomer (D). 3. The solid electrolyte according to claim 1, wherein the lithium ion conductive composition [I] further contains an inorganic filler (E). The curable oligomer (A) is a urethane (meth) acrylate compound (A1) whose molecular terminals are all (meth) acryloyl groups and / or at least one of the molecular terminals is a (meth) acryloyl group and the remainder is a hydrocarbon. The solid electrolyte according to any one of claims 1 to 3, which is a polyisocyanate derivative (A2) which is a group. The solid electrolyte according to any one of claims 1 to 4, wherein the ionic liquid (C) is an imidazolium salt having an alkyl substituent at the 2-position. The solid electrolyte according to any one of claims 3 to 5, wherein the inorganic filler (E) is hydrophilic silicon oxide. Lithium ion conductive composition [I] contains electrolyte solution (F) further, The solid electrolyte in any one of Claims 1-6 characterized by the above-mentioned. The solid electrolyte according to any one of claims 1 to 7, wherein the thickness of the cured film obtained from the lithium ion conductive composition [I] is 5 to 100 µm. A lithium polymer battery comprising the solid electrolyte according to claim 1 sandwiched between a positive electrode and a negative electrode.

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