WO1998048429A1

WO1998048429A1 - Solid polymer electrolyte and its use

Info

Publication number: WO1998048429A1
Application number: PCT/JP1998/001069
Authority: WO
Inventors: Masataka Takeuchi; Shuichi Naijo; Koji Tokita
Original assignee: Showa Denko K.K.
Priority date: 1997-04-18
Filing date: 1998-03-13
Publication date: 1998-10-29

Abstract

A solid polymer electrolyte comprising an organic solvent containing a polymer, an electrolytic salt, ethylene carbonate and ethyl methyl carbonate, and, when desired, inorganic particles; and a lithium secondary battery made by using the electrolyte. The solid electrolyte has good moldability and strength, can be handled easily, and has a high ionic conductivity, a good stability, a long service life, excellent current characteristics, and excellent temperature characteristics over a wide temperature range including a low temperature range of -10 °C or below. The lithium secondary battery is excellent in safety, long-period reliability, and workability in addition to the above-mentioned characteristics.

Description

Description Solid Polymer Electrolyte and Its Use This application claims the benefit of an application based on US Application No. 60/056060 (filing date: September 2, 1997). Technical field

The present invention uses a mixed solvent of ethylene carbonate and ethyl methyl carbonate, has a high ionic conductivity in a wide temperature range, and has a high electrochemical stability and a high polymer solid electrolyte, particularly a low temperature of 11 ° C. or less. It relates to solid polymer electrolytes that can be used in the field.

Further, the present invention relates to a lithium secondary battery using the polymer solid electrolyte, which is excellent in safety and reliability, has high performance, and particularly has good low-temperature characteristics. Background art

Lithium primary batteries and lithium (ion) secondary batteries, which are typical electrochemical devices, have recently been rapidly mounted on small portable devices due to their high energy density, and have shown rapid growth.

Intake example, L i C O_〇 _{_{2, L i N i 0 2}} , L i M n 0 2, M o S metal oxides such as _2, with a metal sulfide in the positive electrode, lithium, lithium alloy, lithium ions Many studies have been made on lithium (ion) secondary batteries using non-aqueous electrolytes composed of organic solvents and lithium salts, using carbon materials and inorganic compounds that can be stored and released for the negative electrode. "Journal O Breakfast 'elect opening Chemical' Sosaieti (Journal of the Electrochemical Society), the first 3 8 Certificates (N o. 3), 6 6 5 pages, 1991," The, M N_〇 ₂ or N i 0 ₂ the battery to the positive electrode has been reported. Organic solvents used in non-aqueous electrolytes include high dielectric constant, high boiling point cyclic Carbonates (propylene carbonate, ethylene carbonate, butylene carbonate, etc.) and ratatones (two-butyl lactone, etc.), low-viscosity linear carbonates (dimethyl carbonate, getyl carbonate, ethyl methyl carbonate), low-viscosity ether compounds (glyme , Diglyme, THF, dioxolane, etc.) have been studied mainly, and high ionic conductivity has been achieved by increasing the dissociation of the electrolyte salt and making it less viscous. Among them, carbonates are widely used because of their wide electrochemical stability range and low reactivity with positive and negative electrode materials (for example, JP-A Nos. 2-10666 and 5-283104). Further, among them, ethylene carbonate is effective for improving the reversibility of a carbon anode such as a graphite anode, and is regarded as an essential solvent for lithium ion batteries currently on the market.

A porous film such as a polyolefin nonwoven fabric or a polyolefin microporous film is used as a separator, which is important as a constituent element other than the positive and negative electrodes and the electrolyte in these lithium primary batteries and lithium (ion) secondary batteries. The function of the separator is required to be such that the positive and negative electrodes are electronically isolated from each other so as not to cause a short circuit, and that the ion transfer in the electrolyte between the positive and negative electrodes is not hindered. In addition, if the battery has the above-described function, it is preferable that the battery be as thin as possible because the energy density of the entire battery is increased. To provide these functions, porous thin films are currently used as separators, and film manufacturing and processing costs are high, which is a factor of high cost. In addition, there was no ability to carry the electrolyte, and the battery easily leaked from the battery to the outside of the component or the elution of the electrode material. This caused long-term reliability and safety problems for the battery.

Recently, a so-called solid polymer electrolyte, which is a combination of a polyethylene oxide polymer and an alkali metal salt, has been receiving attention. Examples of these polymer solid electrolytes,

"British Polymer Journal, Vol. 319, p. 137, 1975" states that a composite of polyethylene oxide and an inorganic metal salt of an alkali metal has an ionic conductivity. Is indicated. In addition, a comb-shaped polymer with oligooxyethylene introduced into the side chain is responsible for ionic conductivity. It has been reported that the thermal mobility of oxyethylene chains can be increased to improve ionic conductivity. For example, "The Journal of Physical Chemistry", Vol. 89, pp. 87, 1984, added oligooxyethylene to the side chain of polymethacrylic acid. An example is described in which an alkali metal salt is compounded. In addition, the Journal of the American Chemical Society, Vol. 106, p. 6854, 1984, describes a polyphosphazene having an oligooxyethylene side chain. An example of complexing an alkali metal salt is described. It is said that the polymer itself forms a complex with the lithium salt, which is the electrolyte, and can exhibit ionic conduction by thermal motion of the polymer chain. Therefore, there is basically no need for a hole through which the electrolyte passes, as in the current separator. However, these are not practically satisfactory in terms of membrane strength and ionic conductivity.

Ion conductivity of the solid polymer electrolyte that is generally considered, despite improved to ^{^{1 0 _ 4 ~1 0 _ 5}} SZ cm position at that value put in room temperature, when compared to a liquid ion conductive material It is a level lower by two digits or more. Also 0. At low temperatures below C, the ionic conductivity is further reduced. Furthermore, when these solid electrolytes are incorporated into a battery in the form of a thin film, processing techniques such as compounding with electrodes and ensuring contactability were difficult, and there were problems with the manufacturing method.

As described in "Journal of Applied Electrochemistry", Vol. 5, pp. 63-69, 1975, polyacrylonitrile, polyvinylidene fluoride gel, etc. It has been reported that a so-called polymer gel electrolyte obtained by adding a solvent and an electrolyte to a thermoplastic polymer or a crosslinked polymer has high ionic conductivity. In addition, Japanese Patent Publication No. 58-36828 reports that a similar polymer gel electrolyte obtained by adding a solvent and an electrolyte to a polyalkyl methacrylate ester has a high ionic conductivity. However, although these polymer gel electrolytes have high ionic conductivity, they impart fluidity, so they cannot be handled as completely solid, have poor film strength and film forming properties, and are applied to batteries. Then, a short circuit is likely to occur, and a sealing problem occurs as in the case of the liquid ion conductive material.

U.S. Pat.No. 4,357,401 states that a polymer solid electrolyte consisting of a crosslinked polymer containing a heteroatom and an ionizable salt reduces the crystallinity of the polymer, lowers the glass transition point, and improves ionic conductivity. However, it was about 10-5 Scm at room temperature, which was still insufficient.

Further, US Pat. No. 4,792,504 proposes a solid polymer electrolyte in which an electrolyte comprising a metal salt and a non-protonic solvent is impregnated in a crosslinked network of polyethylene oxide. These indicate that the oxetylene chain can impregnate not only the lithium salt but also a non-protonic solvent, and that a uniform solid polymer electrolyte without pores impregnated with an electrolyte that can be used as a separator for lithium batteries can be obtained. It can be provided. However, even in this system, the ionic conductivity was still insufficient at 10 · ⁴ S cm. In addition, the addition of the solvent reduced the film strength, which caused a problem in that it was difficult to handle during production or when used in batteries and the like.

Japanese Patent Publication No. 3-73081 (U.S. Pat. No. 4,908,283) discloses that a polymer comprising an acryloyl-modified polyalkylene oxydono electrolyte salt such as polyethylene glycol diacrylate and an organic solvent is irradiated with an actinic ray such as ultraviolet light to polymer. Methods for forming a solid electrolyte have been disclosed and attempts have been made to reduce the polymerization time. Also, US Pat. No. 4,830,939 and Japanese Patent Application Laid-Open No. 5-109310 (US Pat. No. 5,037,712) disclose a composition comprising a crosslinkable polyethylene unsaturated compound, an electrolyte, an actinic ray inactive solvent, an ultraviolet ray, an electron beam or the like. A similar method for forming a polymer solid electrolyte containing an electrolytic solution by irradiating the same is disclosed. In these systems, the ionic conductivity is improved because the amount of electrolyte in the solid polymer electrolyte is increased, but it is still insufficient, and the membrane strength tends to deteriorate.

“Solid 'State' Ionicas, 7, 7, 75,

In 1982 "by combining L i C 1 0 ₄ / polyethylene O key further alumina particles to the side double coalesce a polymer solid electrolyte, ion conductivity is lowered It has been reported that the strength of a solid polymer electrolyte can be improved without such a problem. Japanese Patent Publication No. 6-140052 (W094 / 06165) proposes a solid electrolyte in which a polyalkylene oxide isocyanate crosslinked polymer inorganic oxide composite is impregnated with a non-aqueous electrolytic solution. The strength of the polymer solid electrolyte has been increased.

In order to solve these problems, the present inventors have proposed an ionic conduction using a composite comprising a polymer obtained from a (meth) acrylate prepolymer containing an oxyalkylene group having a urethane bond and an electrolyte. A novel solid polymer electrolyte (Japanese Patent Publication No. 6-187822 (US Pat. No. 5,597,661)) was proposed. The ionic conductivity of this polymer solid electrolyte is at a high level of 10 ⁴ SZ cm (room temperature) without adding a solvent, but becomes 10 ³ S / cm or more when a solvent is further added. In addition, the film quality was good and improved to the extent that it could be obtained as a self-supporting film. In addition, this prepolymer has good polymerizability, and when applied to batteries, there is also a processing merit that it can be polymerized after being assembled into batteries in a prepolymer state and solidified.

However, in a high molecular solid electrolyte to which ethylene carbonate, which is particularly effective as a solvent, is added, there is a problem that the ion conductivity and current characteristics are extremely reduced at a low temperature of 0 ° C or lower because ethylene carbonate is easily crystallized. there were. Purpose of the invention

The present invention provides a solid polymer electrolyte that has good molding process, good strength, easy handling, high ion conductivity over a wide temperature range, stability, low cost, and excellent safety and reliability. The purpose is to do. It is another object of the present invention to provide a lithium secondary battery which is excellent in safety and reliability, has high performance, and has a small capacity reduction even at a temperature of 10 ° C or less, and has a shape-free shape. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic sectional view of an embodiment of a thin solid state battery according to the present invention. Disclosure of the invention

The present inventors have conducted intensive studies in view of the above problems, and as a result, have found that the above problems can be improved by adding a mixed solvent of ethylene carbonate and ethyl methyl carbonate to a polymer solid electrolyte. In particular, it has been found that the low-temperature characteristics can be significantly improved by controlling the amount of ethylene carbonate and ethyl methyl carbonate added in a specific range.

Furthermore, the present inventors have developed a lithium secondary battery using the above polymer solid electrolyte, which has a wide operating temperature range, good current characteristics, good cycleability, excellent safety and reliability, and a high processability with shape flexibility. It has been found that it becomes a single-density energy battery.

In the description of the present specification, the expression “oxyalkylene” includes oligooxyalkylenes and polyoxyalkylenes each containing at least one oxyalkylene group.

That is, the present invention has achieved the above object by developing the following.

[1] A polymer solid electrolyte comprising a polymer, an electrolyte salt, and an organic solvent containing ethylene carbonate and ethyl methyl carbonate.

[2] A polymer solid electrolyte comprising a polymer, an electrolyte salt, an organic solvent containing ethylene carbonate and ethyl methyl carbonate, and inorganic fine particles.

[3] The total weight of ethylene carbonate and ethyl methyl carbonate is 100% by weight of the polymer. /. The polymer solid electrolyte according to the above [1] or [2], wherein the weight ratio between ethylene carbonate and ethyl methyl carbonate is 2: 1 to 1:10.

[4] The polymer solid electrolyte according to any of [1] to [3], wherein the polymer has an oxyalkylene and / or urethane structure.

[5] The polymer has the general formula (1) or the general formula (2)

CH ₂ = C (R ¹ ) CO— (1)

0

CH ₂ = CiR ² ) C [OR ³ ] _x NHCO— (2)

II II OO [Wherein, R ¹ and R ² represent a hydrogen atom or an alkyl group, and R ³ represents a divalent group having 10 or less carbon atoms. The divalent group may contain a hetero atom, and may have any of a linear, branched, or cyclic structure. X represents 0 or a numerical value from 1 to 10; However, the values of R ² , R 3 and x in the polymerizable functional group represented by the formula (1) or (2) which are present in plurals in the same molecule are independent of each other and may be the same or different. ]

The polymer according to any one of the above [1] to [4], which is at least one kind of polymer obtained by polymerizing a heat and Z or actinic ray polymerizable compound having a polymerizable functional group represented by Solid electrolyte.

[6] The polymer solid electrolyte according to any of [2] to [5], wherein the inorganic fine particles are alumina-based fine particles having a crystal particle diameter of 0.1 / zm or less and a BET specific surface area of 5 Om ² / g.

[7] The polymer solid electrolyte according to any one of the above [1] to [6], wherein the at least one electrolyte salt is a lithium salt.

[8] At least one electrolyte salt _{L i PF 6, L i BF} 4 and Z or _{_{L i N (CF 3 SO 2}} ) 2 in which said [7] a polymer solid electrolyte according.

[9] The polymer solid electrolyte according to the above [7] or [8], wherein the negative electrode active material is lithium, a lithium alloy, a carbon material capable of storing and releasing lithium ions, an inorganic oxide capable of storing and releasing lithium ions, and lithium ion. A lithium secondary battery using at least one material selected from inorganic chalcogenides that can store and release lithium ions and polymers that can store and release lithium ions.

Hereinafter, the present invention will be described in detail.

The solid polymer electrolyte of the present invention is characterized in that an organic solvent containing ethylene carbonate (EC) and ethyl methyl carbonate (EMC) is added. As a result, high ionic conductivity is obtained in a wide temperature range, and current characteristics and temperature characteristics when applied to electrochemical devices such as batteries are improved.

The mixing ratio (weight) of EC and EMC is usually 3: 1 to 1:15 for EC: EMC. Can be used. If the amount of EC is too large, the deposition temperature of EC at a low temperature becomes high, and particularly in a solid polymer electrolyte, the deposition temperature tends to be even higher. On the other hand, if the amount is too small, the ionic conductivity is reduced and the life of the battery is shortened. Therefore, the preferable mixture ratio (weight) of EC and EMC is EC: EMC is 2: 1 to: 1: 10, 5: 5 to: L: 10 is more preferable, and 4: 6 to 1: 9. Is particularly preferred.

The higher the content of the solvent (including EC and EMC) in the polymer solid electrolyte, the easier the diffusion of electrolyte salts or ions, and the higher the ionic conductivity in that case. The mechanical strength of the electrolyte decreases. Therefore, the preferable addition amount is in the range of 100% to 1500% by weight of the polymer weight in the polymer solid electrolyte of the present invention, more preferably 200% to 1200% by weight, and more preferably 300% to 1200% by weight. 1000% by weight is particularly preferred.

In addition to ECZEM C added in the above preferred range, other organic solvents may be added to the polymer solid electrolyte of the present invention. As the organic solvent that can be used, the polymer used in the solid polymer electrolyte of the present invention, has good compatibility with EC and EMC, has a high boiling point, has high solubility of the electrolyte salt, and is suitable for the electrochemical element used. A stable one that does not adversely affect is good. That is, a compound having a large dielectric constant, a boiling point of 60 ° C or more, and a wide electrochemical stability range is suitable. Examples of such a solvent include carbonates such as propylene carbonate, dimethyl carbonate, and getyl carbonate; ethers such as 1,2-dimethoxetane, dioxolan, and 2-methyltetrahydrofuran; triethylene dalicol dimethyl ether; Oligoethers, esters such as methyl propionate and methyl methoxypropionate, aromatic nitriles such as benzonitrinole and tolunitrile, dimethylformamide, N-methylpyrrolidone, N-butylpyrrolidone and dimethyl Examples thereof include sulfur compounds such as sulfoxide and sulfolane, and phosphoric esters. Among them, ethers, oligoethers, esters and carbonates are preferable, and esters, Carbonates are particularly preferred.

The polymer which is a main component of the polymer solid electrolyte of the present invention must be non-electroconductive and capable of absorbing and retaining various organic polar solvents. Examples of such high molecules include heteroatoms such as polyalkylene oxide, polyalkyl imine, polyacrylonitrile, poly (meth) acrylate, polyphosphazene, polyfutsudani vinylidene, polyurethane, polyamide, polyester, and polysiloxane. Polar thermoplastic polymer or cross-linked polymer. In particular, the crosslinked polymer is suitable as the polymer used in the present invention because it has a high strength after absorbing the solvent, has a high solvent retentivity, and is a viscoelastic material. The crosslinks shown here include not only those in which the crosslinks are formed by covalent bonds, those in which the side chains are crosslinked by ionic bonds or hydrogen bonds, and those in which the crosslinks are physically crosslinked via various additives. included.

Among the above polymers, those containing an oxyalkylene perethane structure such as polyalkylene oxide or polyurethane in the molecular structure are preferable because of their good compatibility with various polar solvents and good electrochemical stability. From the viewpoint of stability, those having a fluorocarbon group such as vinylidene fluoride in the molecular structure are also preferable.

Further, among the above polymers, a polymerizable agent represented by the general formula (1) or (2)

〇Η ₂ = 0 (^) 〇0— (1)

0

CH ₂ = C (R ² ) C [OR ³ ] _x NHCO— (2)

0 0

[Wherein, R ¹ and R ² represent a hydrogen atom or an alkyl group, and R ³ represents a divalent group having 10 or less carbon atoms. The divalent group may contain a hetero atom, and may have any of a linear, branched, or cyclic structure. X is 0 or 1-10 Shows the numerical value of. However, R l in the polymerizable functional group represented by a plurality of the above general formula in the same molecule (1) or (2), the value of R ^2, R 3 and x are each independently either the same or different May be. ]

A polymer obtained by curing at least one type of polymerizable compound having the following formulas by heating and irradiating with Z or actinic rays is preferable because it easily forms a film in a state containing a solvent and has good film strength.

Among them, the following general formula (3) or (4)

CH ₂ = C (R ¹ ) CO— R ⁴ — (3)

II

0

CH ₂ = (4)

0 [wherein, R 1, R ² , R ³ and x have the same meaning as in the general formula (1) or (2), and R ⁴ and R ⁵ represent an oxyalkylene group and Z or fluorocarbon, It is a divalent group containing oxyfluorocarbon. ]

A polymer obtained by curing at least one polymerizable compound having a polymerizable functional group represented by the formula (1) by heating and / or irradiating with active light is particularly preferable. The method for synthesizing the compound having a functional group represented by the general formula (1) used in the polymer solid electrolyte of the present invention is not particularly limited. For example, an acid chloride and a compound having a hydroxyl group at a terminal, For example, it can be easily obtained by reacting with oligooxyalkyleneol.

For example, a compound having one functional group represented by the general formula (1) is obtained by reacting an acid chloride with a monoalkyl oligoalkylenedarilicol in a molar ratio of 1: 1 according to the following reaction formula. By doing so, it is easily obtained. CH ₂ = C (R ¹ ) COCI + HO (CH ₂ CH (R ⁶ ) 0) _m R ⁷ ► CH ₂ = C (R ¹ ) COO (CH ₂ CH (R ⁶ ) O) _m R ⁷

[Wherein, R1 has the same meaning as in the general formula (1), R ⁶ is H or an alkyl group having 10 or less carbon atoms, and R ⁷ is an alkyl group having 10 or less carbon atoms. For example, a compound having two functional groups represented by the general formula (1) can be easily prepared by reacting an acid chloride with an oligoalkylene glycol at a molar ratio of 2: 1 according to the following reaction formula. Is obtained.

2CH ₂ = C (R,) COCI + HO (CH ₂ CH (R ⁶ ) 0) _m H ► CH ₂ = C (R ¹ ) COO (CH ₂ CH (R ⁶ ) 0) _m CO (R ¹ ) C = CH ₂

Wherein, R1 represents the same meaning as the general formula (1), R ⁶ is H or an alkyl group having 1 0 carbon atoms. ]

The method for synthesizing the compound having a polymerizable functional group represented by the general formula (2) used in the polymer solid electrolyte of the present invention is not particularly limited. For example, CH ₂ = C (R2) CO [OR ³ ] _It can be obtained by reacting xNCO with an oligooxyalkyleneol (wherein, R ² , R ³ and X each have the same meaning as in the general formula (2)).

As a specific method, a compound having one ethylenically unsaturated group is, for example, a methacryloyl isocyanate compound (hereinafter abbreviated as Ml) or an acryloyl isocyanate compound (hereinafter abbreviated as AI). ) And a monoalkyl oligoalkylene glycol in a molar ratio of 1: 1 according to the following reaction formula. CH ₂ = C (R ² ) CO [OR ³ ] _x NCO + HO (CH ₂ CH (R ⁶ ) 0) _m R ⁷ ► CH ₂ = C (R ² ) CO [OR ³ ] _x NHCOO (CH ₂ CH (R ⁶ ) O) _m R ⁷

[Wherein, R ² , R ³ and x have the same meaning as in the general formula (2), R ⁶ is H or an alkyl group having 10 or less carbon atoms, and R ⁷ is an alkyl group having 10 or less carbon atoms. It is. ]

A compound having two ethylenically unsaturated groups can be easily obtained, for example, by reacting Ml or AIs with an oligoalkylene glycol in a molar ratio of 2: 1.

Compounds having three ethylenically unsaturated groups include, for example, Ml and / or AIs and a triol obtained by addition-polymerizing a trihydric alcohol such as glycerin with an alkylene oxide. It can be easily obtained by reacting at a molar ratio of

The compound having four ethylenically unsaturated groups is, for example, a compound having a molar ratio of 4: 1 between Ml and / or AI and a tetraol obtained by addition-polymerizing an alkylene oxide to a tetrahydric alcohol such as pentaerythritol. It is easily obtained by reacting in a ratio.

Compounds having five ethylenically unsaturated groups include, for example, Ml and / or AIs and pentaol obtained by addition polymerization of α-D-dalcoviranose with alkylene oxide, in a ratio of 5: 1. It can be easily obtained by reacting at a molar ratio of

The compound having six ethylenically unsaturated groups is, for example, a compound of the formulas I and 及び or an AI and a hexanol obtained by addition-polymerizing an alkylene oxide to mannitol in a molar ratio of 6: 1. It is easily obtained by reacting.

A method for synthesizing a compound having a polymerizable functional group represented by the general formula (1) or (2) having a fluorocarbon group and a Z or oxyfluorocarbon group is not particularly limited. Has one polymerizable functional group as Compounds are prepared by reacting MIs or AIs with monools such as 2,2,3,3,4,4,4-heptafluoro-1-butanol in a molar ratio of 1: 1 according to the following reaction formula. Can be easily obtained.

ΟΗ ₂ = 0 (Ρ ^Ί ) ΟΟΟ (ΟΗ ₂ ) ₂ ΝΟΟ + CF ₃ (CF ₂ ) ₂ CH ₂ OH ► 〇Η ₂ = 〇 (^) 〇ΟΟ (0Η ₂ ) ₂ ΝΗ〇ΟΟ〇Η ₂ (〇 Ε ₂ ) ₂ 〇Ρ ₃ Compounds having two polymerizable functional groups are, for example, ΜI or AIs and diols such as 2,2,3,3-tetrafluoro-1,4-butanediol. It can be easily obtained by reacting at a molar ratio of 2: 1 according to the following reaction formula.

2CH ₂ = C (R ¹ ) COO (CH ₂ ) ₂ NCO + HOCH ₂ (CF ₂ ) ₂ CH ₂ OH {CH ₂ = C (R ¹ ) COO (CH ₂ ) ₂ NHCOOCH ゥ CF ₂ —} ₂ General formula The polymer obtained by polymerizing a compound having only one polymerizable functional group represented by (1) or (2) does not have a cross-linked structure, and has insufficient film strength. The danger of a short circuit is great, and it is better not to use it alone. Therefore, it is necessary to copolymerize and crosslink with a compound having two or more polymerizable functional groups represented by the general formula (1) or (2).

Considering the strength of the thin film of the polymer solid electrolyte, the number of polymerizable functional groups represented by the general formula (1) or (2) contained in one molecule is more preferably three or more.

Further, among the compounds having a polymerizable functional group represented by the general formula (1), the polymer obtained from the compound having a polymerizable functional group represented by the general formula (2) contains a urethane group, Good properties and high film strength when thinned It is preferred.

The polymer which is preferable as a component of the polymer solid electrolyte of the present invention is obtained by polymerizing at least one kind of a compound having a polymerizable functional group represented by the general formula (1) or (2), or It is obtained by polymerization as a polymerization component.

The polymer used for the polymer solid electrolyte of the present invention, even if it is a homopolymer of a compound having a polymerizable functional group represented by the general formula (1) or the general formula (2), belongs to this category. It may be a copolymer of at least one kind, or a copolymer of at least one kind of the compound and another polymerizable compound.

The other polymerizable compound copolymerizable with the compound having a polymerizable functional group represented by the general formula (1) or (2) is not particularly limited. For example, atarylamide, metharylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, atariloylmorpholine, metharylylmorpholine, N, N-dimethylaminopropyl (meth) acrylamide, etc. (Meth) acrylamide-based compounds, styrene-based compounds such as styrene and para-methylstyrene, N-vinylamide-based compounds such as N-vinylacetamide and N-vinylformamide, and alkyl vinyl ethers such as ethyl-butyl ether Can be mentioned.

As the polymerization method, a general method utilizing the polymerizability of an acryloyl group or a methallyl group in the polymerizable compound can be employed. That is, a radical polymerization catalyst such as azobisisobutyronitrile, benzoyl peroxyside, a CF ₃ COOH or the like is added to these monomers alone or a mixture of these monomers and the above-mentioned copolymerizable polymerizable compound. Pro Tonsan, using BF _3, cationic polymerization catalysts such as Lewis acids a, etc. 1 C 1 3 or butyl lithium, sodium Na Futaren, the Anion polymerization catalyst such as lithium alkoxide, radical polymerization, cationic polymerization or Anion polymerization Can be done. Further, depending on the polymerizable compound, radical polymerization can be performed only by heating in an oxygen-free state. The polymer used for the polymer solid electrolyte of the present invention preferably contains an oxyalkylene structure. In that case, the number of oxyalkylene chains, that is, in R ⁴ in the general formula (3), or The number of repetitions n of the oxyalkylene group contained in R ⁵ in the general formula (4) is preferably in the range of 1 to 1,000, particularly preferably in the range of 5 to 100.

The polymer used in the polymer solid electrolyte of the present invention may be a homopolymer of a compound having a functional group represented by the general formula (1) or (2) as described above, The copolymer described above may be used, or a copolymer of at least one of these compounds and another polymerizable compound may be used.

Further, the polymer used for the polymer solid electrolyte of the present invention is a polymer obtained from at least one compound having a functional group represented by the general formula (1) or (2) and a polymer obtained by combining the polymer and the compound. It may be a mixture of a copolymer as a polymerization component and another polymer.

For example, a polymer obtained from at least one compound having a functional group represented by the general formula (1) or (2) and Z or a copolymer having the compound as a copolymer component, polyethylene oxide, and polypropylene oxide The mixture of the present invention with a polymer such as polyacrylonitrile, polybutadiene, polymethacrylic acid (or acrylic) ester, polystyrene, polyphosphazenes, polysiloxane or polysilane, polyvinylidene fluoride, or polytetrafluoroethylene. It may be used for a molecular solid electrolyte.

It is preferable to add various inorganic fine particles to the solid polymer electrolyte of the present invention. This not only improves strength and film thickness uniformity, but also causes fine pores to be formed between the inorganic fine particles and the polymer, and when immersed in an electrolyte solution, the polymer solid electrolyte The free electrolyte is dispersed inside, and the ionic conductivity and mobility can be increased without impairing the strength gap. In addition, the addition of the inorganic fine particles increases the viscosity of the polymerizable composition, and has an effect of suppressing the separation even when the compatibility between the polymer and the solvent is insufficient. As the inorganic fine particles to be used, non-electroconductive and electrochemically stable ones are selected. Further, those having ion conductivity are preferred. Specific examples include ct,] 3, γ-alumina, silica, titania, magnesia, and composite oxides of two or more of these, and ion-conductive or non-conductive ceramic fine particles such as zeolite. The inorganic fine particles preferably have a secondary particle structure in which primary particles are aggregated, from the viewpoint of increasing the strength of the polymer solid electrolyte and increasing the amount of retained electrolyte. Specific examples of the inorganic fine particles having such a structure include silica ultrafine particles such as AEROSIL (manufactured by Nippon AEROSIL) and alumina ultrafine particles, and particularly preferred are alumina ultrafine particles in terms of stability and composite efficiency.

For the purpose of increasing the amount of electrolyte in the separator and increasing ionic conductivity and mobility, the specific surface area of the inorganic fine particles is preferably as large as possible. Preferably, 50 m2 / g or more is more preferable.

The crystal particle size of such inorganic fine particles is not particularly limited as long as it can be mixed with the polymerizable composition, but the average particle size is preferably 0.001 / Zm to 10 μm, and more preferably 0.01 μm to 1 μm. m is particularly preferred.

In addition, various shapes such as a sphere, an egg, a cube, a rectangular parallelepiped, a cylinder or a rod can be used.

If the added amount of the inorganic fine particles is too large, there arises a problem that the strength and ionic conductivity of the polymer solid electrolyte are reduced and that the film is difficult to be formed. Therefore, the amount of addition is preferably 5 Owt% or less, more preferably 0.1 to 30 wt%, based on the solid polymer electrolyte.

When producing the solid polymer electrolyte of the present invention, at least one kind of (meth) acryloyl-based compound having a polymerizable functional group represented by the general formula (1) or (2), at least one kind of electrolyte salt, A polymerizable composition comprising a solvent containing EC and EMC, or a polymerizable composition obtained by adding at least one kind of inorganic fine particles thereto, or a polymerizable composition obtained by further adding at least one kind of polymerization initiator After coating and coating on various substrates, the (meth) acryloyl-based compound is polymerized and cured by heating and irradiating with Z or actinic light. , Can be recommended.

The temperature for the polymerization depends on the type of the polymerizable compound having a polymerizable functional group represented by the general formula (1) or (2) and the type of the initiator, but may be any temperature at which the polymerization occurs. The temperature may be in the range of ° C to 200 ° C. In the case of polymerizing by irradiation with actinic rays, an actinic ray initiator such as benzylmethylketanol or benzophenone may be used, depending on the type of polymerizable compound having a polymerizable functional group represented by the general formula (1) or (2). When used, polymerization can be carried out by irradiating ultraviolet light of several mW or more or an electron beam, a beam or the like.

By using the solid polymer electrolyte of the present invention in combination with another porous polymer film, the strength can be improved. However, depending on the type of polymer used, the shape of the film, and the composite ratio, the ion conductivity of the separator after absorbing the electrolyte may be lowered and the stability may be deteriorated. Examples of the porous film used include a porous polyolefin film such as a mesh-like polyolefin sheet such as a polypropylene nonwoven fabric or a polyethylene net, a polyolefin microporous film such as Celgard (trade name), a nylon nonwoven fabric, and a polyester net. However, a polyolefin porous film is preferable in terms of stability. The porosity may be about 10 to 90%, but it is preferable that the porosity is as large as possible as long as the strength permits, and the preferable porosity is in the range of 40 to 90%.

The method of compounding is not particularly limited, but includes, for example, at least one kind of (meth) atalyloyl-based compound having a polymerizable functional group represented by the general formula (1) or (2), at least one kind of electrolyte salt, and EC and EMC. After impregnating a porous polymer film with a polymerizable composition comprising a solvent, or a polymerizable composition obtained by adding at least one type of inorganic fine particles thereto, or a polymerizable composition further obtained by adding at least one type of polymerization initiator thereto Polymerizing the (meth) acryloyl compound This method is recommended because the method can be uniformly combined and the film thickness control is simple.

When the solid polymer electrolyte of the present invention is applied to a battery, the solid polymer electrolyte of the present invention has a high electrolytic solution retention property and has no pores, so that liquid leakage and short circuit hardly occur, and the operating temperature range is wide. A non-aqueous battery with high current, long cycle life, and high safety and reliability can be obtained. In addition, since liquid leakage and short circuit hardly occur, the battery can be made thin and a battery with a simple package can be obtained.

FIG. 1 shows a schematic cross-sectional view of an example of a thin-film battery as a nonaqueous battery manufactured in this manner. In the figure, 1 is a positive electrode, 2 is a polymer solid electrolyte of the present invention, 3 is a negative electrode, 4 is a current collector, and 5 is an insulating resin sealant.

As the negative electrode active material used in the non-aqueous battery of the present invention, one having a low oxidation-reduction potential with an alkali metal ion such as an alkali metal, an alkali metal alloy, a carbon material, a metal oxide or a metal chalcogenide as a carrier is used. It is preferable to use it because a high-voltage, high-capacity battery can be obtained. Among such negative electrode active materials, lithium metal or lithium alloys such as lithium / aluminum alloy, lithium Z lead alloy, and lithium Z antimony alloy are particularly preferable because they have the lowest redox potential. In addition, carbon materials are particularly preferable in that they have a low oxidation-reduction potential when they occlude lithium ions, and are stable and safe. The carbon material for lithium ion can occluding and releasing, natural graphite, artificial graphite, vapor grown graphite, petroleum coke, coal co one task, pitch carbon, polyacene, C ₆ o, hula etc. c _70; one alkylene ethers And the like.

Therefore, when such a negative electrode is used in a battery using an alkali metal ion as a carrier, an alkali metal salt is required as an electrolyte. The type of alkali metal Shokushio, for _{_{example, L i CF 3 S 0 3}} , L i PF 6, L i C 10 4, L i BF 4, L i SCN, L i A s F 6, L i N _{_{_{(CF 3 SO 2) 2,}}} N a CF 3 S 0 3, L i I, N a PF 6, N a C 10 4, N a I, N a BF 4, Na As F 6, KCF 3 S0 3, KPF ₆ and KI can be mentioned.

In the case of a carbon material negative electrode, not only alkali metal ions but also quaternary ammonium Nidium salts, quaternary phosphonium salts, transition metal salts, and various protonic acids can also be used. Such _{_{_{electrolytes, (CH 3) 4 NBF 4}}} , (CH 3 CH 2) 4 NC 10 4 4 Grade Anmoniumu salts such as, transition metal salts such as _{A g CI 0 4, (CH} 3) 4 P BF quaternary Hosuhoniumu salt ₄ such as salts of organic San及Piso such as p-toluenesulfonic acid, hydrochloric acid, and the like inorganic acids such as sulfuric acid. Of these, quaternary ammonium salts, quaternary phosphonium salts, and metal salts of alkali metal are preferred because of their high output voltage and large dissociation constant. Among the quaternary ammonium salts, those having different substituents on the nitrogen of the ammonium ion such as (CH ₃ CH ₂ ) (CH ₃ CH ₂ CH ₂ CH ₂ ) ₃ NBF ₄ Is preferred because it has a large dissociation constant.

In the configuration of the non-aqueous battery of the present invention, a high-voltage, high-capacity battery is obtained by using a positive electrode active material having a high oxidation-reduction potential such as a metal oxide, a metal sulfide, a conductive polymer, or a carbon material for the positive electrode. Is preferred. Among such positive electrode active materials, metal oxides such as dicobalt oxide, manganese oxide, vanadium oxide, nickel oxide, and molybdenum oxide, molybdenum sulfide, and the like have a high packing density and a high volume capacity density. Metal sulfides such as titanium sulfide and vanadium sulfide are preferable, and manganese oxide, nickel oxide, cobalt oxide and the like are particularly preferable in terms of high capacity and high voltage.

The method for producing metal oxides and metal sulfides in this case is not particularly limited, and examples thereof include a general electrolytic method and a general electrolytic method described in “Electrochemistry, Vol. 22, p. 574, 1954”. It is manufactured by a heating method. Further, when used in lithium batteries by these positive electrode active material, during the production of the battery, examples Ebashi 1 〇 ₀ 0 ₂ Ya L i _x Mn0 metal oxide lithium element in the form of ₂ like, or metal sulfide It is preferable to use it in a state where it is inserted (composite) into the device. The method for introducing the lithium element is not particularly limited, for example, a method for electrochemically introducing lithium ions, or a method for introducing Li ₂ C ₃ as described in US Pat. No. 4,357,215. It can be carried out by mixing a metal oxide or the like with a salt and heating the mixture. In addition, a conductive polymer is preferable because it is flexible and easily formed into a thin film. Examples of the conductive polymer include polyaniline, polyacetylene and its derivatives, polyparaphenylene and its derivatives, polypyrrole and its derivatives, polychenylene and its derivatives, polypyridinediyl and its derivatives, and polyisothianaphthenile. Polyarylene vinylenes such as polyphenylene vinylene and derivatives thereof, polyfurylene and derivatives thereof, polyselenophene and derivatives thereof, polyparaphenylenevinylene, polychenylenevinylene, polyfurylenevinylene, polynaphthenylenevinylene, polyselenophenvinylene, polypyridinylvinylene and the like And the like. Above all, a polymer of an aniline derivative soluble in an organic solvent is particularly preferable.Examples of carbon materials include natural graphite, artificial graphite, vapor-grown graphite, petroleum coke, coal coke, fluorinated graphite, pitch-based carbon, and polyacene. No. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described more specifically by showing typical examples. These are merely examples for explanation, and the present invention is not limited to these.

Example 1: Synthesis of compound 3

(Compound 1) (Compound 2) (Compound 3)

[Wherein [X ¹ ] is [CH (CH ₃ ) CH ₂₀ ] _x H, or

[X] indicates [CH (CH ₃ ) CH ₂ 0] _× CNHCH ₂ CH ₂ OCC (CH ₃ ) = CH ₂ . ]

0 0 Compound 1 (KOP ^ SI 34.0 mgZg) (50.0 g) and compound 2 (4.6 g) are dissolved in well-purified THF (100 ml) in a nitrogen atmosphere, and then dibutyltin dilaurate (0.44 g) is added. Thereafter, the mixture was reacted at 25 ° C. for about 15 hours to obtain a colorless viscous liquid. From the results of ¹ H-NMR, IR, and elemental analysis, compound 1 and compound 2 reacted one to three, and further, the isocyanate group of compound 2 disappeared, and urethane bond was formed. It turned out that it was generated. Example 2

Compound 3 (1.0 g), ethylene carbonate (EC) (1.8 g), Echirumechi Le carbonate (EMC) (4.2 g), L i PF 6 ( Hashimoto Kasei battery grade)

(0.60 g) and 2,4,6-trimethylbenzoyldipheninolephosphinoxide (trade name Lucylin TPO, manufactured by BASF) (0.005 g) are mixed well in an argon atmosphere, and photopolymerized. The composition was obtained. The water content (curl fisher) of this composition was 30 ppm. This photopolymerizable composition was applied on a PET film under an argon atmosphere, and then irradiated with a chemical fluorescent lamp (FL20S.BL, manufactured by Sankyo Electric Co., Ltd.) for 10 minutes to obtain a polymer of compound 3 impregnated with an ECZEMC-based electrolyte. The finolem was obtained as a free standing film of about 30 μm. The ionic conductivity of this film at 25 ° C. and 120 ° C. was measured by an impedance method and found to be 5.0 × 10 ⁻³ and 0.8 × 10 ⁻³ S / cm, respectively. Example 3

Compound 3 (1.0 g), high-purity γ-alumina heat-treated at 1000 ° C (manufactured by Showa Denko; UA5805; crystal particle diameter 0.03 / zm, average secondary particle diameter 1.8 μπι, BET specific surface area 80 m ² Zg) (0.33 g), EC (1.8g), EMC (4.2 g), L i PF 6 ( Hashimoto Kasei battery grade) (0.60 g), and Rushiri emissions TPO (manufactured by BAS F Corporation) (0.005 g) in an argon atmosphere By mixing well, a photopolymerizable composition was obtained. The water content (Karl Fischer method) of this composition was 3 Oppm.

This photopolymerizable composition was coated on a PET film under an argon atmosphere, and then irradiated with a chemical fluorescent lamp (FL20S.BL, manufactured by Sankyo Electric Co., Ltd.) for 10 minutes. ZUA5805 composite film was obtained as a freestanding film of about 30 μm. 25 ° C for this film, one 20. Measurement of the ionic conductivity at C by an impedance method, respectively, 5.0 X 10- ^3, was 0.8 X 10-3SZ cm. Example 4

Aluminum Numoxide C heat-treated at 1000 ° C instead of UA5805 as alumina-based fine particles (manufactured by Nippon Aerosil; crystal particle diameter 0.013 μπι, average secondary particle diameter about 0.1 / xm (SEM observation), BET specific surface area 10 Om ² g ) Was added in the same manner as in Example 3 except that 0.33 g of the photopolymerizable composition was obtained. The water content (Carno-Fischer method) of this composition was 35 ppm.

The photopolymerizable composition was applied and irradiated with light in the same manner as in Example 3, whereby a polymer Z-aluminum oxide C composite film of compound 3 impregnated with an EC / EMC electrolytic solution was converted into a free-standing film of about 30 μπι. Obtained. 25 ° C of the film was measured for ionic conductivity in one 20 ° C by an impedance method, respectively, 5.5 X 10- ^3, was 1.0 X 10_3SZcm. Example 5

A thermopolymerizable composition was obtained in the same manner as in Example 4 except that benzoyl peroxide (BPO) (0.04 g) was added instead of lucirin T PO (0.005 g) as an initiator. The water content (Karl Fischer method) of this composition was 35 ppm.

This thermopolymerizable composition was coated on a PET film under an argon atmosphere, coated with a PP film, and heated on a hot plate at 80 ° C for 1 hour. A polymer / aluminum oxide C composite film of compound 3 impregnated with EC / EMC electrolyte was obtained as a free-standing film of about 30 / xm. The ionic conductivity of this film at 25 ° C. and at 20 ° C. was measured by an impedance method to be 5.3 × 10-3 and 0.8 × 10-3 sZcm, respectively. Example 6

A photopolymerizable composition was obtained in the same manner as in Example 4 except that 0.50 g of battery grade Li BF ₄ manufactured by Hashimoto Kasei was used instead of Li PF ₆ . The water content of this composition (Carno Reisher method) was 50 ppm.

The photopolymerizable composition was applied and irradiated with light in the same manner as in Example 4 to obtain an electrolyte-impregnated polymer of compound 3 / aluminum moxide C composite film as a self-supporting film of about 30 / xm. Was. The ionic conductivity of this solid electrolyte at 25 ° C. and 20 ° C. was measured by an impedance method and found to be 4.0 × 10 ³ and 0.3 × 10 ³ SZcm. Example 7

Compound 3 (1.0 g), propylene carbonate (PC) (0.4 g), EC (1.4 g), EMC (4.2 g), Li PF ₆ (Hashimoto Chemical Battery Grade)

(0.60 g), aluminum oxide C (0.33 g) heat-treated at 1000 ° C., and lucirin TPO (0.005 g) were mixed well in an argon atmosphere to obtain a photopolymerizable composition. The water content (Karl Fischer method) of this composition was 35 ppm. This photopolymerizable composition was coated on a PET film under an argon atmosphere, and then irradiated with a chemical fluorescent lamp for 10 minutes.As a result, a polymer Z aluminum oxide C composite film impregnated with a PCZECZEMC-based electrolyte was obtained. Obtained as a free-standing film of about 30 μπι. The ionic conductivity of this film measured at 25 ° C and 20 ° C by an impedance method was 6.0 X 10-3 and 1.0 X 10_3 SZcm, respectively. Example 8

Compound 3 (1.0 g), EC (1.5 g), EMC (3.0 g), Jetilka Carbonate (DEC) (1.5 g), Li PF ₆ (Hashimoto Chemical Battery Grade) (0.60 g),

Aluminum oxide C (0.33 g) heat-treated at 1000 ° C. and lucirin TPO (0.005 g) were mixed well in an argon atmosphere to obtain a photopolymerizable composition. The water content (Karl Fischer method) of this composition was 35 ppm. This photopolymerizable composition was applied on a PET film under an argon atmosphere, and then irradiated with a chemical fluorescent lamp for 10 minutes. The polymer / aluminum alloy of compound 3 impregnated with an EC / EMC / DEC electrolyte solution The xyside C composite film was obtained as a free-standing film of about 30 μιη. 25 of this film. C, one twenty. When the ionic conductivity at C was measured by an impedance method, they were 5.0 × 10-3 and 0.7 × 10-3 S / cm, respectively. Example 9: Synthesis of compound 5

CH ₃ (OCH ₂ CH (CH ₃ )) _m OH + CH ₂ = C (CH ₃ ) COOCH ₂ CH ₂ NCO

(Compound 4) (Compound 2)

——► CH ₃ (OCH ₂ CH (CH ₃ )) _m OCONHCH ₂ CH ₂ OCOC (CH ₃ ) = CH ₂

(Compound 5) Compound 4 (average molecular weight Mn = 550) (55 g) and compound 2 (15.5 g) were dissolved in well-purified THF (100 ml) in a nitrogen atmosphere, and then dibutyltin dilaurate (0.66 g) Was added. Thereafter, the mixture was reacted at 25 ° C. for about 15 hours to obtain a colorless viscous liquid. According to the results of 1H-NMR, IR and elemental analysis, compound 4 and compound 2 reacted one-to-one, the isocyanate group of compound 2 disappeared, urethane bond was formed, and compound 5 was formed. and that this and the force ^s I force ivy. Example 10

Compound 5 (0.5 g), Compound 3 (0.5 g) synthesized in Example 1, UA 5805 (0.66 g) heat-treated at 1000 ° C, EC (1.8 g), EMC (4.2 g), LiPF ₆

(Hashimoto Chemical Battery Grade) (0.60 g) and Lucirin TPO (0.005 g) were mixed well in an argon atmosphere to obtain a photopolymerizable composition. Water content of this composition

(Karl Fischer method) was 3 Oppm.

This photopolymerizable composition was coated on a PET film under an argon atmosphere, and then irradiated with a chemical fluorescent lamp for 10 minutes.The copolymer UA5805 composite film of a compound 3 and 5 impregnated with an ECZEMC-based electrolyte solution Was obtained as a free-standing film of about 30 μπι. 25 ° C of the film was measured for ionic conductivity in one 20 ° C at I impedance method respectively, 6.0 X 1 0- ^3, was 0.8 X 1 0-3 S / cm.

Example

Compound 6: CH ₃ (0CH ₂ CH ₂ ) _m 0C0C (CH ₃ ) = CH ₂ (NOF, Blemmer AE-400, Mw 400) (0.3 g), compound 3 (0.5 g) synthesized in Example 1, UA 5 8 05 heat treated at 1000 ° C (0.66 g), EC (1.8 g), EMC (4.2 g), L i PF 6 and (Hashimoto Kasei battery grade) (0.60 g) and Lucirin TPO (0.005 g) The mixture was mixed well in an argon atmosphere to obtain a photopolymerizable composition. The water content (Karl Fischer method) of this composition was 3 Oppm.

This photopolymerizable composition was applied on a PET film under an argon atmosphere, and then irradiated with a chemical fluorescent lamp for 10 minutes.The copolymer ZUA5805 composite of compounds 3 and 6 impregnated with an ECZEMC-based electrolyte solution The film was obtained as a free standing film of about 30 μπι. The ionic conductivity of this film measured at 25 ° C. and 120 ° C. by an impedance method was 4.5 × 10-3 and 0.6 × 10-3 S / cm, respectively. Example 12 Synthesis of Compound 8

CF ₃ (CF ₂ ) ₂ CH ₂ OH CH ₂ = C (CH ₃ ) COOCH ₂ CH ₂ NCO

(Compound 7) (Compound 2)

CF ₃ (CF ₂ ) ₂ CH ₂ OCONHCH ₂ CH ₂ OCOC (CH ₃ ) = CH ₂

(Compound 8) Compound 7 (2,2,3,3,4,4,4-heptafluo-1-butanol, manufactured by Aldrich) (20 g) and Compound 2 (15.5 g) are thoroughly purified in a nitrogen atmosphere. After mixing with THF (100 ml), dibutyltin dilaurate (0.66 g) is added. Thereafter, the mixture was reacted at 25 ° C. for about 15 hours to obtain Compound 8 as a colorless viscous liquid. From the results of 1H-NMR, IR and elemental analysis, compound 7 and compound 2 reacted one to one, and furthermore, the isocyanate group of compound 2 disappeared, and urethane bonds were formed. I understood. Example 13 Synthesis of Compound 10

HOCH ₂ CF ₂ (OCF ₂ CF ₂ ) _n (OCF ₂ ) _m CH ₂ OH 2 CH ₂ = C (CH ₃ ) CO (CH ₂ ) ₂ NCO ——►

O

(Compound 9) (Compound 2)

CH ₂ = C (CH ₃ ) CO (CH ₂ ) ₂ NH OCH ₂ CF ₂ (OCF ₂ CF ₂ ) _n (OCF ₂ ) _m CH ₂ OCNH (CH ₂ ) ₂ OCC (CH ₃ ) = CH ₂

O O 0 0

(Compound 10) Compound 9 (manufactured by Nippon Aodimund Co., Ltd., Zdo 1 average molecular weight 2000) (100 g) and compound 2 (15.5 g) were mixed with well-purified THF (100 ml) in a nitrogen atmosphere. Add dibutyltin dilaurate (0.66 g). Thereafter, by reacting about 1 5 hours at 25 ° C, to afford compound 1 0 as a colorless viscous liquid _c From the results of 1H-NMR, IR and elemental analysis, it was found that Compound 9 and Compound 2 reacted in a ratio of 1: 2, and further, the isocyanate group of Compound 2 disappeared, and a urethane bond was formed. Example 14

Compound 8 (0.7 g), Compound 10 (0.3 g), silica heat-treated at 1000 ° C (Aerosil 200, Aerozil Japan, crystal particle size 0.012 / 2 m, average secondary particle size approx.

0.1 / z m (SEM observation), BET specific surface area 200m2Zg) (0.33 g), EC

(1.0 g), EMC (2.0 g), DEC (1.0 g), L i PF 6 ( Hashimoto Kasei battery grade) (0.60 g),及Pi Lucirin TP O a (0.005 g) were mixed well under an argon atmosphere A photopolymerizable composition was obtained.

The water content (Karl Fischer method) of this composition was 6 Oppm. This photopolymerizable composition was coated on a PET film under an argon atmosphere, and then irradiated with a chemical fluorescent lamp for 10 minutes.The copolymer, a copolymer of Compounds 8 and 10, impregnated with an EC / EMC ZDEC-based electrolyte, 200 composite films were obtained as about 30 zm free standing finolems. 25 ° C of the Fi beam was measured ion Den Shirubedo of one 20 ° C by an impedance method, respectively, 2.0X 1 0- ^3, was 0.4 X 1 0-3S / cm. Example 15

A photopolymerizable composition was obtained in the same manner as in Example 3 except that 0.33 g of magnesium oxide (Micromag 3-150 manufactured by Kyowa Chemical Co., Ltd.) heat-treated at 1000 ° C was added instead of UA5805 as inorganic fine particles. . The water content (Karl Fischer method) of this composition was 35 ppm.

The photopolymerizable composition was applied and irradiated with light in the same manner as in Example 3 to obtain a compound 3 polymer / micromag 3-150 composite film impregnated with ECZEMC electrolyte solution as a self-supporting film of about 30 μm. Was. 25 ° C of this film, - was measured ionic conductivity at 20 ° C by an impedance method was respectively ^{4.3X 10-3, 0.5X 1 0_ 3 SZ} cm. Example 16

Example 3 Example 3 was repeated except that 0.33 g of titanium oxide (Super Titania F-4 manufactured by Showa Denko, crystal particle size 0.028 / m, BET specific surface area 56 m ² Zg) heat-treated at 1000 ° C was added instead of UA 5805 as inorganic fine particles. In the same manner as in the above, a photopolymerizable composition was obtained. The water content (Karl Fischer method) of this composition was 60 ppm.

This photopolymerizable composition was coated and irradiated with light in the same manner as in Example 3, whereby a compound 3 polymer / super titania F-4 composite film impregnated with an EC electrolyte was converted into a self-supporting film of about 30 μπι. Was obtained. 25 ° C for this film, 20 times. When the ionic conductivity at C was measured by the impedance method, it was 4.5 X 10-3 and 0.7 X 10-3 S / cm, respectively. Example 17: Production of lithium cobaltate positive electrode

_{_{L i 2 C0 3 (1 1}} g) and _{_{C o 3 0 4 (24 g}} ) were mixed well under an oxygen atmosphere, heated at 800 ° C 24 hours, the L i C O_〇 ₂ powder by grinding Obtained. This L i C o0 ₂ powder, acetylene black and polyvinylidene fluoride, the weight ratio of 8: 1: 1 mixture, further excess of N- Mechirupirori Don solution was added to obtain a gel composition. This composition was applied and molded on an aluminum foil of about 25 μπι to a thickness of 1 cmXlcm and a thickness of about 180 μm. Furthermore, by heating and drying under vacuum at about 100 ° C for 24 hours, a lithium cobaltate positive electrode (75 mg) was obtained. Example 18: Production of graphite negative electrode

MCMB graphite (manufactured by Osaka Gas), vapor-grown graphite fiber (manufactured by Showa Denko KK: average fiber diameter 0.3 μm, average fiber length 2.0 m, heat treated at 2700 ° C), polyvinylidene fluoride An excess N-methylpyrrolidone solution was added to the mixture having a weight ratio of 8.6: 0.4: 1.0 to obtain a gel composition. This composition was applied and molded on a copper foil of about 15 μm to a thickness of 10 mm × 10 mm and a thickness of about 250 μm. Furthermore, it was heated and vacuum-dried at about 100 ° C. for 24 hours to obtain a graphite negative electrode (35 mg). Example 19: Production of lithium ion secondary battery

In the argon atmosphere glove box, the graphite negative electrode (10 mm x 10 mm) produced in Example 17 was impregnated with electrolyte (1 ML i PF ₆ / EC + EMC (3: 7)). Then, the polymer solid electrolyte Z-aluminum oxide C composite film (12 mm × 12 mm) prepared in Example 4 was laminated on a graphite negative electrode, and the lithium cobaltate positive electrode (lOmmX l O mm) and an electrolyte impregnated with electrolyte (1M Li PF ₆ / EC + EMC (3: 7)), seal the battery end with epoxy resin, and use graphite / cobalt oxide lithium ion. A secondary battery was obtained. FIG. 1 shows a cross-sectional view of the obtained battery.

This battery was charged and discharged at an operating voltage of 2.75 to 4.1 V and a current of 0.5 mA at 60 ° C, 25 ° C, and 20 ° C. The maximum discharge capacity was 7.2 mAh, 7.2 mAh, and 6.5 mA, respectively. h.

When charge and discharge were repeated at 25 ° C, operating voltage 2J5 to 4.1V, charge 0.5mA, and discharge 2.5mA, the maximum discharge capacity was 6.8mAh, and the cycle life until the capacity was reduced to 50% was 560. It was times. Example 20: Production of lithium ion secondary battery

Example 1 was repeated except that the [Compound 3 + 5-based polymer solid electrolyte] / UA5805 film produced in Example 10 was used instead of the compound 3-based polymer solid electrolyte / aluminum oxide C composite film. A lithium ion secondary battery having the cross-sectional view shown in FIG.

Operate the battery at 60 ° C, 25 ° C, --20 ° C, operating voltage 2.75 ~ 4.1 V, current 0.5 When the battery was charged and discharged at mA, the maximum discharge capacities were 7.2 mAh, 7.2 mAh, and 6.8 mAh, respectively.

When charge and discharge were repeated at 25 ° C, operating voltage 2.75 to 4.1 V, charge 0.5 mA, and discharge 2.5 mA, the maximum discharge capacity was 7.0 mAh, and the cycle life until the capacity was reduced to 50% was 480. It was times. Example 21: Production of lithium ion secondary battery

The same procedure as in Example 19 was performed except that the compound 3-based thermopolymerized polymer solid electrolyte Z-aluminum oxide C film prepared in Example 5 was used instead of the compound 3-based polymer solid electrolyte aluminum oxide C film. A lithium ion secondary battery having the cross-sectional view shown in FIG. 1 was manufactured.

Use this battery at 60 ° C, 25 ° C, and 20 ° C. When the battery was charged and discharged with an operating voltage of 2.75 to 4.1 V and a current of 0.5 mA at C, the maximum discharge capacity was 7.2 mAh, 7.2 mAh, and 6.4 mAh, respectively.

When charge and discharge were repeated at 25 ° C, operating voltage 2.75 to 4.1 V, charge 0.5 mA, and discharge 2.5 mA, the maximum discharge capacity was 6.6 mAh, and the cycle life until the capacity was reduced to 50% Was 5 10 times. Example 22: Production of lithium ion secondary battery

In a argon atmosphere glove box, the graphite anode (10 mm X 10 mm) produced in Example 18 was impregnated with an electrolyte solution (1 ML i PF ₆ / EC + EMC (3: 7)). The compound 3 / aluminum oxide C-based photopolymerizable compound prepared in Example 4 was applied to a thickness of 30 / zm, and irradiated with a chemical fluorescent lamp for 10 minutes under an argon atmosphere. A polymer Z-impregnated Z3 aluminum oxide C composite film was formed directly on the graphite negative electrode. Further Example 1 lithium cobaltate positive electrode prepared in 7 (1 OmmX 1 0 mm) to the electrolytic solution _{(1M L i PF 6 / EC} + EMC (3: 7)) was also impregnated with The end of the battery was sealed with an epoxy resin to obtain a graphite / cobalt oxide lithium ion secondary battery as shown in FIG.

Use this battery at 60 ° C, 25 ° C, and 20 ° C. When the battery was charged and discharged with an operating voltage of 2.75 to 4.1 V and a current of 0.5 mA at C, the maximum discharge capacities were 7.2 mAh, 7.2 mAh, and 6.6 mAh, respectively.

When charge and discharge were repeated at 25 ° C, operating voltage 2.75 to 4.1 V, charge 0.5 mA, and discharge 2.5 mA, the maximum discharge capacity was 7.2 mAh, and the cycle until the capacity was reduced to 50% The life was 680 times. Industrial applicability

The polymer solid electrolyte of the present invention has high ionic conductivity over a wide temperature range and electrochemical stability because it contains EC and an organic solvent containing EMC that is effective in lowering the crystallization temperature of EC as a plasticizer. It can improve current characteristics, temperature characteristics, and life when applied to electrochemical devices such as batteries. In particular, it can be used without problems even at temperatures as low as −20 ° C or less.

In the present invention, by adding inorganic fine particles to the polymer solid electrolyte, the strength is improved, the handling is facilitated, the diffusion of the electrolyte salt is facilitated, and the current characteristics and cycle characteristics of the electrochemical element are improved. be able to.

According to the present invention, the fact that a polymerizable compound having a (meth) acrylic group and / or a urethane (meth.,) Acrylic group has excellent curing properties is used, and these compounds and an electrolyte salt are used. After the polymerizable composition containing the organic organic solvent or / and the inorganic fine particles is placed on the substrate, the polymer solid electrolyte containing the EC / EMC solvent is applied to the substrate by heating or irradiation with actinic rays such as ultraviolet rays. It became possible to manufacture easily.

Further, according to the present invention, by using the solid polymer electrolyte and the negative electrode capable of occluding and releasing lithium ions, a high energy density, a large extraction current, a wide operating temperature range, a long cycle life, and a high Leakage, short circuit is less likely to occur, A lithium (ion) secondary battery with excellent safety, long-term reliability, and processability can be obtained. In addition, since liquid leakage and short-circuiting do not easily occur, a thin lithium ion (ion) secondary battery with a simple package can be obtained.

Claims

The scope of the claims

1. A polymer solid electrolyte comprising a polymer, an electrolyte salt, and an organic solvent containing ethylene carbonate and ethyl methyl carbonate.

2. A polymer solid electrolyte comprising a polymer, an electrolyte salt, an organic solvent containing ethylene carbonate and ethyl methyl carbonate, and inorganic fine particles.

3. The total weight of ethylene carbonate and ethyl methyl carbonate is at least 100% by weight with respect to the polymer, and the weight ratio of ethylene carbonate and ethyl methyl carbonate is 2: 1 to 1:10. Or the high molecular solid electrolyte according to 2.

4. High: The solid polymer electrolyte according to any one of claims 1 to 3, including a structure.

5. The polymer has the general formula (1) or the general formula (2)

CH ₂ = C (R) CO— (1)

0

CH ₂ = C (R ² ) CrOR ³ ] _x NHCO— (2)

O o

Wherein, Rl及Pi R ² represents a hydrogen atom or an alkyl group, R ³ represents a divalent group having 1 0 carbon atoms. The divalent group may contain a hetero atom, and may have any of a linear, branched, or cyclic structure. X represents 0 or a numerical value from 1 to 10; However, if there are multiple occurrences of the same molecule in the formula (1) or (2) The values of RR ² , R 3 and x in the polymerizable functional groups to be obtained are each independent and may be the same or different. ]

The solid polymer electrolyte according to any one of claims 1 to 4, which is at least one kind of polymer obtained by polymerizing a heat and / or actinic ray polymerizable compound having a polymerizable functional group represented by .

6. The high molecular solid electrolyte according to any one of claims 2 to 5, wherein the inorganic fine particles are alumina-based fine particles having a crystal particle diameter of 0.1 µm or less and a BET specific surface area of 50 m ² Zg or more.

7. The polymer solid electrolyte according to any one of claims 1 to 6, wherein at least one kind of electrolyte salt is a lithium salt.

8. at least one electrolyte salt _{L i PF 6, L i BF} 4 and / or _{_{L i N (CF 3 S0 2}} ) 2 a polymer solid electrolyte in the range 7 according claims is.

9. Lithium, lithium alloy, carbon material capable of occluding and releasing lithium ions, inorganic oxide capable of occluding and releasing lithium ions, and lithium ion as the negative electrode active material, using the polymer solid electrolyte according to claim 7 or 8. A lithium secondary battery that uses at least one material selected from inorganic chalcogenides that can store and release, and polymers that can store and release lithium ions.