JP2007056225A - Resin composition for electrolyte, ion conducting electrolyte, and secondary battery using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition for an electrolyte, providing an ion conducting electrolyte exhibiting high ion conductivity and having improved cycling characteristics; to provide the ion conducting electrolyte obtained therefrom, exhibiting the high ion conductivity and having good cycling characteristics; and to provide a secondary battery using the electrolyte. <P>SOLUTION: The resin composition for the electrolyte comprises a lithium salt and a salt monomer constituted of an ammonium cation having a polymerizable functional group and an organic anion having a polymerizable functional group as essential components. The salt monomer is constituted of an ammonium cation having a long-chain organic group containing the polymerizable functional group and an organic anion having a long-chain organic group containing the polymerizable functional group. The ion conducting electrolyte is constituted of the resin composition for the electrolyte. The secondary battery includes the ion conducting electrolyte as a constituent element. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a resin composition for an electrolyte, an ion conductive electrolyte obtained therefrom, and a secondary battery using the same.

In recent years, the development of electronics in the information society has been remarkable, and along with this, secondary devices used as power sources for portable information devices such as mobile phones, notebook personal computers and digital cameras, portable medical devices and welfare devices. Expectations for battery performance are increasing. As a power source secondary battery material that satisfies these requirements, a polymer solid electrolyte has been attracting attention.
In order to cope with such secondary batteries, lithium ion conductive polymer electrolytes exhibiting high ionic conductivity have been required, and as polymer electrolytes that improve ionic conductivity, double bonds There has been proposed an electrolyte that obtains good ionic conductivity by using a salt monomer composed of an amine component having an acid component and an acid component having a double bond (see, for example, Patent Document 1). According to this electrolyte, good ionic conductivity can be obtained, but a better characteristic is required in a long charge / discharge cycle, and a polymer electrolyte that exhibits high ionic conductivity and further improves cycle characteristics is obtained. It was sought after.
JP 2003-142160 A

  According to the present invention, a resin composition for an electrolyte that can provide an ion conductive electrolyte that exhibits high ionic conductivity and can improve cycle characteristics, and exhibits high ionic conductivity obtained from the resin composition for cycle characteristics. It becomes possible to provide a good ion conductive electrolyte and a secondary battery using the same.

As a result of intensive studies to achieve the above object, the present inventor has achieved the above object by the present invention of the following first to fourth items.
1. A resin composition for an electrolyte comprising a lithium salt, a salt monomer composed of an ammonium cation having a polymerizable functional group and an organic anion having a polymerizable functional group, wherein the salt monomer has a polymerizable functional group. A resin composition for an electrolyte comprising an ammonium cation having a long-chain organic group and an organic anion having a long-chain organic group containing a polymerizable functional group.
2. The resin composition for electrolyte according to claim 1, wherein the salt monomer is a compound represented by the general formula (1).

（式中、Ｐ₁およびＰ₂は、それぞれ重合性官能基を含む置換基を示し、Ｘはアニオン原子で構成される基を示し、Ｒ₁〜Ｒ₅は、それぞれ、置換または無置換の、アルキル基、アルケニル基、アリール基、アラルキル基、アラルケニル基および複素環残基から選ばれる有機基を示し、同一であっても互いに異なっていてもよく、いずれか一対またはそれ以上が環状構造を形成していても構わない。ただしＲ₁、Ｒ₂は炭素数が５〜２０の直鎖又は分岐のアルキル基である。）

(Wherein P ₁ and P ₂ each represent a substituent containing a polymerizable functional group, X represents a group composed of an anionic atom, and R _{1 to} R ₅ each represents a substituted or unsubstituted group, An organic group selected from an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an aralkenyl group and a heterocyclic residue, which may be the same or different from each other, and any one or more of them forms a cyclic structure (However, R ₁ and R ₂ are linear or branched alkyl groups having 5 to 20 carbon atoms.)

3. An ion conductive electrolyte comprising the resin composition for an electrolyte according to item 1 or 2.
4). A secondary battery comprising the ion-conductive electrolyte according to item 3 as a constituent element.

ADVANTAGE OF THE INVENTION According to this invention, the resin composition for electrolytes which can obtain the ion conductive electrolyte which expresses high ion conductivity and can improve cycling characteristics can be provided.
By using the resin composition for electrolyte of the present invention, an ion conductive electrolyte having high ion conductivity and good cycle characteristics in a secondary battery can be provided.
Further, by using the ion conductive electrolyte of the present invention, it is possible to provide a secondary battery with good cycle characteristics.

  The present invention is a resin composition for an electrolyte comprising a salt monomer composed of a lithium salt, an ammonium cation having a polymerizable functional group and an organic anion having a polymerizable functional group, wherein the salt monomer is polymerized. An electrolyte resin composition comprising an ammonium cation having a long-chain organic group containing a polymerizable functional group and an organic anion having a long-chain organic group containing a polymerizable functional group. The ion conductive electrolyte exhibits high ion conductivity, and the secondary battery obtained using the ion conductive electrolyte has good cycle characteristics.

  The salt monomer used in the present invention is a salt monomer composed of an ammonium cation having a long-chain organic group containing a polymerizable functional group and an organic anion having a long-chain organic group containing a polymerizable functional group. Examples of the structure include a compound having a long-chain organic group between the polymerizable functional group and the ammonium cation, and a long-chain organic group between the polymerizable functional group and the organic anion. it can. In addition, examples of the long-chain organic group include a linear or branched alkyl group, among which a linear or branched alkyl group having 5 to 20 carbon atoms is preferable, and a long-chain organic group in an ammonium cation and an organic anion. May be the same or different. The salt monomer preferably has a structure represented by the general formula (1).

式（１）中、Ｐ₁およびＰ₂は、それぞれ重合性官能基を含む置換基を示し、Ｘはアニオン原子で構成される基を示し、Ｒ₁〜Ｒ₅は、それぞれ、置換または無置換の、アルキル基、アルケニル基、アリール基、アラルキル基、アラルケニル基および複素環残基から選ばれる有機基を示し、同一であっても互いに異なっていてもよく、いずれか一対またはそれ以上が環状構造を形成していても構わない。ただしＲ₁、Ｒ₂は炭素数が５〜２０の直鎖又は分岐のアルキル基である。

In formula (1), P ₁ and P ₂ each represent a substituent containing a polymerizable functional group, X represents a group composed of an anionic atom, and R _{1 to} R ₅ each represents a substituted or unsubstituted group. An organic group selected from an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an aralkenyl group and a heterocyclic residue, which may be the same or different from each other, and any one or more of them is a cyclic structure May be formed. However, R < ₁ >, R < ₂ > is a C5-C20 linear or branched alkyl group.

  When the salt monomer contains a long-chain organic group, the effect of plasticizing the ion conductive electrolyte is exhibited, and the ion mobility of the electrolyte salt is improved. It is considered that the cycle characteristics can be improved in a secondary battery using the same.

  The polymerizable functional group in the salt monomer is not limited as long as it is a functional group that can be polymerized by radical polymerization, ionic polymerization, coordination polymerization, redox polymerization, or the like, but a group having a carbon-carbon double bond is available. Preferably, radical polymerization is possible with active energy rays or heat. Examples of such functional groups include (meth) acryloyl groups, (meth) acryloyloxy groups, (meth) acrylamide groups, allyl groups, vinyl groups, styryl groups, and unsaturated ring structures typified by oxazoline rings. A group having A plurality of polymerizable functional groups contained in the molecule of the salt monomer may be the same or different from each other.

Further, the ammonium cation constituting the salt monomer is an onium cation generated from an amine compound, and the amine compound is any amine compound such as an aliphatic amine compound, an aromatic amine compound, a nitrogen-containing heterocyclic amine compound, or the like. Needless to say, it is not particularly limited as long as it is a cation having a positive charge resulting from an amine and having a long-chain organic group containing at least one polymerizable functional group.
Specifically, a quaternary ammonium cation in which a nitrogen atom is substituted with four organic groups R is first mentioned. The organic radical R is a substituted or unsubstituted, alkyl group C _n H _{2n + 1} -, an aryl group _{(Rc) m -C 6 H 5} -m - , an aralkyl group _{(Rc) m -C 6 H 5} -m - C _n H _2n -, alkenyl group Rc-CH = CH-Rc-, aralkenyl _{(Rc) m -C 6 H 5} -m -CH = CH-Rc-, alkoxyalkyl group _{Rc-O-C n H 2n} - An acyloxyalkyl group Rc—COO—C _n H _2n — (in the R, Rc is a substituted or unsubstituted alkyl group having 20 or less carbon atoms, or hydrogen, and when there are a plurality thereof, they may be different from each other. m is an integer of 1 or more and 5 or less, and n is an integer of 1 or more and 20 or less. Examples of the substituent when substituted in R and Rc include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, and n-pentyl. Group, neopentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group and other linear or branched alkyl groups, cyclohexyl group and 4-methylcyclohexyl group Linear or branched alkoxy such as alkyl group, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, tert-butoxy group and n-hexyloxy group Group, cyclic alkoxy group such as cyclohexyloxy group, methoxymethoxy group, methoxyethoxy group, Alkoxyalkoxy groups such as toxiethoxy group, methoxypropoxy group, ethoxypropoxy group and propoxypropoxy group, phenyl group, p-tolyl group, m-tolyl group, o-tolyl group, p-chlorophenyl group, m-chlorophenyl group, o -Aryl groups such as chlorophenyl groups, phenoxy groups, m-methylphenoxy groups, o-methylphenoxy groups, p-chlorophenoxy groups, m-chlorophenoxy groups, o-chlorophenoxy groups and pn-butylphenoxy groups Aryloxy group, phenylthio group, p-methylphenylthio group, m-methylphenylthio group, o-methylphenylthio group, o-ethylphenylthio group, p-propylphenylthio group and 2,4,6-trimethylphenyl Arylthio groups such as thio groups, methylcarbonylamino Group, ethylcarbonylamino group, n-propylcarbonylamino group, isopropylcarbonylamino group, n-butylcarbonylamino group and other alkylcarbonylamino groups, methoxycarbonylamino group, ethoxycarbonylamino group, n-propoxycarbonylamino group, iso Alkoxycarbonylamino groups such as propoxycarbonylamino group and n-butoxycarbonylamino group, alkylcarbonyl groups such as methylcarbonyl group, ethylcarbonyl group, n-propylcarbonyl group, isopropylcarbonyl group and n-butylcarbonyl group, methylcarboxy group Alkylcarboxy group such as ethylcarboxy group, n-propylcarboxy group, isopropylcarboxy group and n-butylcarboxy group, methoxycarboxy group, ethoxy group Alkoxycarboxy groups such as sicarboxy group, n-propoxycarboxy group, isopropoxycarboxy group and n-butoxycarboxy group, methoxycarbonylmethoxy group, ethoxycarbonylethoxy group, ethoxycarbonylmethoxy group, n-propoxycarbonylmethoxy group, isopropoxy group Examples thereof include alkoxycarbonylalkoxy groups such as a carbonylmethoxy group and an n-butoxycarbonylmethoxy group, and these substituents may contain a halogen atom or a heteroatom. Furthermore, examples of the substituent include a cyano group and halogen atoms such as fluorine, chlorine and bromine. R may include a hetero atom. The four Rs may be different or the same. However, R ₁ and R ₂ in the general formula (1) are preferably linear or branched alkyl groups having 5 to 20 carbon atoms, and more preferably 10 to 20 carbon atoms.

  As an ammonium cation constituting the salt monomer, as an ammonium cation other than the above ammonium cation, an aromatic ammonium cation such as a pyridinium cation, a pyraridinium cation and a quinolinium cation, a pyrrolidinium cation, a piperidinium cation and a piperazi An ammonium cation such as an aliphatic heterocyclic ammonium cation such as a nium cation, a heterocyclic ammonium cation containing a heteroatom other than nitrogen such as a morpholine cation, and an unsaturated nitrogen-containing heterocyclic cation such as an imidazolium cation Can be mentioned. Further, the cyclic ammonium cation may be a cation having a different nitrogen position or a cation having a substituent on the ring. It may be a cation having a substituent containing a hetero atom.

  Specific examples of the cation having a long-chain organic group containing a polymerizable functional group constituting the salt monomer include 2-hexyltrimethylammonium cation methacrylate, 2-heptyltrimethylammonium methacrylate cation, 2-octyltrimethylammonium methacrylate. Cations, 2-nonyltrimethylammonium cation methacrylate, 2-decyltrimethylammonium cation methacrylate, 2-dodecyltrimethylammonium methacrylate cation, 2-eicosyltrimethylammonium methacrylate cation, 2-hexyltrimethylammonium acrylate, 2- Heptyltrimethylammonium cation acrylate, 2-octyltrimethylammonium acrylate cation, 2-nonyltrimethyacrylate Ammonium cation, 2-decyltrimethylammonium acrylate cation, 2-decyltrimethylammonium acrylate acrylate, 2-ecosyltrimethylammonium acrylate acrylate, 2-acrylic acid-1,4-dibutylcyclohexyltrimethylammonium cation, 3-methacrylamide Hexyltrimethylammonium cation, 3-methacrylamideamidoheptyltrimethylammonium cation, 3-methacrylamideamidooctyltrimethylammonium cation, 3-methacrylamidononyltrimethylammonium cation, 3-methacrylamideamidodecyltrimethylammonium cation, 3-methacrylamideamidododecyltrimethylammonium cation, 3-Methacrylamide eicosyltrimethylammo Cation, 3-acrylamidohexyltrimethylammonium cation, 3-acrylamidoheptyltrimethylammonium cation, 3-acrylamidooctyltrimethylammonium cation, 3-acrylamidononyltrimethylammonium cation, 3-acrylamidododecyltrimethylammonium cation, 3-acrylamidoeicosyltrimethylammonium cation 3-vinylbenzenehexyltrimethylammonium cation, 3-vinylbenzeneheptyltrimethylammonium cation, 3-vinylbenzeneoctyltrimethylammonium cation, 3-vinylbenzenenonyltrimethylammonium cation, 3-vinylbenzenedodecyltrimethylammonium cation, 3-vinylbenze And eicosyltrimethylammonium cation.

Further, the organic anion constituting the salt monomer is not particularly limited as long as it is an anion having a long-chain organic group containing a polymerizable functional group. However, when the polymer in the present invention is formed, the above-mentioned salt is used as the anion. Preferred is a group having an ionic functional group involved in ionic interaction with the cation of the monomer, in particular ammonium cathin, and / or an ionic functional group involved in ionic interaction with the lithium salt, for example, RO proton of the hydroxyl group-containing organic compounds such as alcoholates and phenolates are eliminated ^- anion;, RS protons such as thiolate and thiophenolate is eliminated ^- anion; sulfonate anion RSO ₃ ^-, carboxylate anion RCOO ^-;, part of the hydroxyl groups of phosphoric acid and phosphorous acid is substituted with an organic group Phosphorus derivatives anion _{R x (OR) y (O} ) z P - ( where, x, y, z are zero or an integer and, x + y + 2z = 3 or x + y + 2z = 5) ;, substituted borate R _x (OR) _y B ⁻ (where x and y are integers of 0 or more and x + y = 4); substituted aluminum anion R _x (OR) _y Al ⁻ (where x and y are integers of 0 or more and x + y = 4) ;, carbanion (EA) ₃ C ⁻ , nitrogen anion (EA) ₂ N ^{− and the} like. Especially as an organic anion, a polymerizable functional group is present in RSO ₃ ⁻ , RCOO ⁻ , RPO ₃ ²⁻ , and (RO ₂ S) ₂ N ⁻ which are anions derived from sulfoxyl, carboxyl, phosphoxyl and sulfonimide groups. Those having the following are preferred. (Wherein, R represents hydrogen, a substituted or unsubstituted, alkyl group C _n H _{2n + 1} -, an aryl group _{(Rc) m -C 6 H 5} -m -, an aralkyl group (Rc) _m -C ₆ H _{5-m -C n H 2n -} , alkenyl group Rc-CH = CH-Rc-, aralkenyl _{(Rc) m -C 6 H 5} -m -CH = CH-Rc-, alkoxyalkyl group Rc-O-C a group selected from _n H _2n — and an acyloxyalkyl group Rc—COO—C _n H _2n — (in the above R, Rc is a substituted or unsubstituted alkyl group having 20 or less carbon atoms, or hydrogen, and when there are plural groups) M may be different from each other, m is an integer of 1 to 5, n is an integer of 1 to 20. However, R ₁ in the general formula (1) is a linear or branched alkyl group having 5 to 20 carbon atoms. Are preferred, and 10 to 20 are more preferred). It may also contain a hetero atom, and when there are two or more R atoms in the molecule, they may be the same or different from each other, and EA represents a hydrogen atom or an electron withdrawing group. Also included are those in which some or all of the hydrogen atoms on the carbon of R are replaced by halogen atoms, and those in which fluorine atoms are particularly substituted are preferred cases. Examples of the substituent when substituted in R and Rc include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, and n-pentyl. Group, neopentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group and other linear or branched alkyl groups, cyclohexyl group and 4-methylcyclohexyl group Linear or branched alkoxy such as alkyl group, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, tert-butoxy group and n-hexyloxy group Group, cyclic alkoxy group such as cyclohexyloxy group, methoxymethoxy group, methoxyethoxy group, Alkoxyalkoxy groups such as toxiethoxy group, methoxypropoxy group, ethoxypropoxy group and propoxypropoxy group, phenyl group, p-tolyl group, m-tolyl group, o-tolyl group, p-chlorophenyl group, m-chlorophenyl group and o -Aryl groups such as chlorophenyl groups, phenoxy groups, m-methylphenoxy groups, o-methylphenoxy groups, p-chlorophenoxy groups, m-chlorophenoxy groups, o-chlorophenoxy groups and pn-butylphenoxy groups Aryloxy group, phenylthio group, p-methylphenylthio group, m-methylphenylthio group, o-methylphenylthio group, o-ethylphenylthio group, p-propylphenylthio group and 2,4,6-trimethylphenyl Arylthio group such as thio group, methylcarbonyl Mino group, ethylcarbonylamino group, n-propylcarbonylamino group, isopropylcarbonylamino group, alkylcarbonylamino group such as n-butylcarbonylamino group, methoxycarbonylamino group, ethoxycarbonylamino group, n-propoxycarbonylamino group, Alkoxycarbonylamino groups such as isopropoxycarbonylamino group and n-butoxycarbonylamino group, alkylcarbonyl groups such as methylcarbonyl group, ethylcarbonyl group, n-propylcarbonyl group, isopropylcarbonyl group and n-butylcarbonyl group, methylcarboxyl group Group, ethylcarboxy group, n-propylcarboxy group, isopropylcarboxy group, n-butylcarboxy group and other alkylcarboxy groups, methoxycarboxy group, Alkoxycarboxy groups such as toxicarboxy group, n-propoxycarboxy group, isopropoxycarboxy group and n-butoxycarboxy group, methoxycarbonylmethoxy group, ethoxycarbonylethoxy group, ethoxycarbonylmethoxy group, n-propoxycarbonylmethoxy group, isopropoxy Examples thereof include alkoxycarbonylalkoxy groups such as a carbonylmethoxy group and an n-butoxycarbonylmethoxy group, and these substituents may contain a halogen atom or a heteroatom. Furthermore, examples of the substituent include a cyano group and halogen atoms such as fluorine, chlorine and bromine.

  Specific examples of the organic anion having a long-chain organic group containing a polymerizable functional group constituting the salt monomer include 3-vinylbenzenehexylsulfonic acid, 3-vinylbenzeneheptylsulfonic acid, 3-vinylbenzeneoctylsulfonic acid, 3-vinylbenzenenonylsulfonic acid, 3-vinyldodecylhexylsulfonic acid, 3-vinylbenzeneeicosylsulfonic acid, 3-vinylbenzenepentylcyclohexylsulfonic acid, 4-vinylbenzeneoctylsulfonic acid, phthalic acid-2- (methacryloyloxy) ) Octyl, phthalic acid-3- (methacryloyloxy) octyl, phthalic acid-4- (methacryloyloxy) octyl, phthalic acid-2- (acryloyloxy) octyl, phthalic acid-3- (acryloyloxy) octyl, phthalic acid- 4- (Acry Yloxy) such as octyl, and the like.

The salt monomer used in the present invention is more preferably a compound comprising a combination of a sulfonate anion RSO ₃ ⁻ and a quaternary ammonium cation. Examples thereof include the following compounds, but are not limited thereto.

Salt monomer (1)

Salt monomer (2)

  When the electrolyte resin composition of the present invention is used as an ion conductive electrolyte, a salt monomer composed of an ammonium cation having a polymerizable functional group and an organic anion having a polymerizable functional group is polymerized and used as a polymer. Including a long-chain organic group in the salt monomer exhibits an effect of plasticizing the ion conductive electrolyte, improves ion mobility of the electrolyte salt, exhibits high ionic conductivity, and It is considered that cycle characteristics can be improved in a secondary battery using an ion conductive electrolyte. Moreover, the said salt monomer has an effect which accelerates | stimulates dissociation of lithium salt to lithium ion by ionic interaction with lithium salt by including lithium salt as said electrolyte salt. In addition, due to the ionic interaction between the ammonium cation and the organic anion, the dissociated lithium ion reacts with the ammonium cation and has the effect of keeping the lithium ion free without being coordinated in the polymer. Can do. This is also considered to contribute to the improvement of lithium ion conductivity.

Examples of the lithium salt used in the present invention include LiPF ₆ , LiClO ₄ , LiAsF ₆ , LiBF ₄ , LiCF ₃ SO ₃ , LiC ₂ F ₅ SO ₃ , LiC ₄ F ₉ SO ₃ , LiN (CF ₃ SO ₂ ) _2. , LiN (C ₂ F ₅ SO ₂ ) ₂ and LiC (CF ₃ SO ₂ ) ₃ . You may use these individually or in mixture of 2 or more types.

In the present invention, when the salt monomer is polymerized, peroxides such as benzoyl peroxide, lauroyl peroxide, cumyl peroxide, potassium persulfate and hydrogen peroxide, azobis (isobutyronitrile) and azobis (2 In addition to known thermal radical polymerization initiators such as azo compounds such as 1,4-dimethylvaleronitrile), various general initiators such as photopolymerization initiators such as diphenyliodonium hexafluoroantimonate and triphenylsulfonium tetrafluorophosphate are used. can do.
In addition, for the purpose of adjusting the starting temperature, the combined use of the thermal initiation reaction / photoinitiation reaction, the initiation of a time difference, etc., it is also possible to use a mixture of these initiators.

  The polymerization of the salt monomer in the resin composition for electrolyte of the present invention can be carried out by various known polymerization methods such as radical polymerization, ionic polymerization, coordination polymerization, redox polymerization, polycondensation and addition condensation polymerization, particularly preferably. Radical polymerization by irradiation with active energy rays or heating. As the active energy ray to be irradiated, ultraviolet rays, electron beams, visible rays, far ultraviolet rays and the like can be used. As irradiation amount, 0.1-50 Mrad is preferable and 0.5-30 Mrad is more preferable. The irradiation time is preferably 5 seconds to 120 minutes, and more preferably 10 seconds to 60 minutes. Examples of the heating temperature include 40 to 150 ° C., and the heating time is preferably 5 minutes to 6 hours, and more preferably 30 minutes to 3 hours.

  In the present invention, a plasticizer can be used as necessary. Examples of the plasticizer include cyclic / chain carbonate solvents such as propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate and ethyl methyl carbonate, and ether solvents such as dimethyl ether, ethylene glycol dimethyl ether, tetrahydrofuran, dioxane and dioxolane. Amide solvents such as dimethyl sulfoxide and dimethyl acetoxide, ketone / ester / lactam solvents such as methyl ethyl ketone, methyl butyl ketone, γ-butyrolactone and n-methyl pyrrolidone, and sulfur-containing solvents such as sulfolane. You may use these individually or in mixture of 2 or more types.

  As content of each component in the resin composition for electrolytes of this invention, 0.1-99.9 wt% of the said salt monomer and 0.1-99.9 wt% of lithium salts are preferable, More preferably, a salt monomer Is 3 to 97 wt%, and the lithium salt is 3 to 97 wt%. Further, the content in the case of using a polymerization initiator is preferably about 0.01 to 30 mol%, more preferably about 0.1 to 30 mol% with respect to the number of moles of all polymerizable functional groups contained in the electrolyte system. 1 to 20 mol%. As another component, when using a plasticizer, it is preferable to contain 0.1-99 wt% in the resin composition for electrolytes, More preferably, a plasticizer is 0.5-90 wt%.

  The resin composition for an electrolyte of the present invention can be obtained by mixing each of the above components. In some cases, the salt monomer may be polymerized in advance, or the salt monomer may be polymerized after mixing. Also good. The electrolyte resin composition thus obtained is preferably liquid or pasty when used in an ion conductive electrolyte.

As a method for producing the lithium ion conductive electrolyte of the present invention, a known polymerization method is prepared by preparing a mixture of the above-mentioned salt monomer, an electrolyte resin composition containing a lithium salt, a polymerization initiator, and optionally other additives. By polymerization, an electrolyte can be obtained.
As an example of a specific manufacturing method, first, the resin composition for electrolyte obtained above and other additives are mixed, and then this mixture is irradiated with active energy rays, heated, or the like to form a resin composition for electrolyte. This is carried out by polymerizing and curing the salt monomer in the product. More specifically, for example, when the salt monomer is solid in the production of the resin composition for electrolyte, it is mixed and ground in advance. After making into a uniform powdery mixture, it is dissolved in an electrolyte solution containing a lithium salt at room temperature to produce a resin composition for an electrolyte, and a mixture with additives added as required There is a method of pouring into the cell and heating it at a predetermined temperature to cure. Moreover, a plasticizer may be added as appropriate, and an electrolytic solution in which a lithium salt is dissolved in a plasticizer in advance may be used. Further, using a solvent such as tetrahydrofuran, methanol and acetonitrile, the salt monomer and lithium salt are dissolved to obtain a resin composition for an electrolyte, and the mixture to which other additives are added is heated and cured, and then the solvent is added. The method of removing or substituting with the electrolyte solution used for a battery is mentioned.
Depending on the structure of the cell, a lithium ion conductive electrolyte can be obtained by a known method such as a casting method or a solid phase polymerization method in addition to the injection.

  The secondary battery of the present invention comprises the lithium ion conductive electrolyte obtained above as a constituent element, and can be manufactured by combining a positive electrode and a negative electrode in addition to the lithium ion conductive electrolyte.

The active material used for the positive electrode used in the battery of the present invention is preferably a transition metal oxide containing lithium having a high energy density and excellent reversible lithium ion insertion / extraction, such as LiCoO ₂ . Examples include lithium cobalt oxide, lithium manganese oxide such as LiMn ₂ O ₄ , lithium nickel oxide such as LiNiO ₂ , a mixture of these oxides, and a part of nickel in LiNiO ₂ substituted with cobalt or manganese. . Examples of the negative electrode active material include carbon-based materials from which lithium ions can be inserted and desorbed. Examples thereof include natural graphite, artificial graphite, mesocarbon microbeads, and graphite.

As an example of a method for producing a secondary battery using the lithium ion conductive electrolyte of the present invention, first, a positive electrode active material such as LiCoO ₂ , a conductive agent such as graphite, and a binder such as poly (vinylidene fluoride). A positive electrode mixture is prepared by mixing the agent, and this positive electrode mixture is dispersed in N-methyl-2-pyrrolidone to obtain a slurry-like positive electrode mixture. This positive electrode mixture is uniformly applied to both surfaces of a positive electrode current collector made of an aluminum foil having a thickness of 20 μm, etc., dried, and then compression molded with a roll press to obtain a positive electrode.

  Next, a negative electrode active material such as graphite powder and a binder such as poly (vinylidene fluoride) are mixed to prepare a negative electrode mixture, and this negative electrode mixture is dispersed in N-methyl-2-pyrrolidone. To make a slurry-like negative electrode mixture. This negative electrode mixture is uniformly applied to both surfaces of a negative electrode current collector made of a copper foil having a thickness of 15 μm, etc., dried, and then compression molded with a roll press to obtain a negative electrode.

  The negative electrode and the positive electrode obtained as described above are brought into close contact with each other through a separator made of a polyethylene microporous film having a thickness of 25 μm, and wound to form an electrode wound body. The electrode wound body is insulated. While enclosing in the exterior film which consists of material, the monomer electrolyte solution obtained above is inject | poured in an exterior film. Next, the outer peripheral edge of the exterior film is sealed, the positive electrode terminal and the negative electrode terminal are sandwiched between the openings of the exterior film, and the electrode winding body is sealed in the exterior film under reduced pressure. Next, this is heated at a temperature of 50 ° C. to 60 ° C. for 5 minutes to 8 hours to obtain a secondary battery using a lithium ion conductive electrolyte.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in more detail, this invention is not limited at all by this.

Example 1
[Synthesis of ammonium cation (11) having polymerizable functional group of salt monomer (1)]
5.21 g (50 mmol) of styrene and 6.23 g (50 mmol) of 1-chloro-5-fluoropentane were mixed and stirred for 4 hours in a water bath (20 ° C.) while mixing boron fluoride. To this, 3.55 g (60 mmol) of trimethylamine was added, and the mixture was gently stirred for 3 hours to obtain a colorless and transparent solution. This solution was reprecipitated with 200 ml of hexane to obtain 10.57 g of an ammonium cation (11) containing a polymerizable functional group of the salt monomer (1) as a white solid. The composition of the ammonium cation containing the polymerizable functional group of the obtained salt monomer (1) was confirmed by proton nuclear magnetic resonance spectrum ( ¹ H-NMR), and it was confirmed that synthesis was in progress.

[Synthesis of Organic Anion (12) Having Polymerizable Functional Group of Salt Monomer (1)]
Styrene 5.21 g (50 mmol), 1-chloropentane 5.32 g (50 mmol), and aluminum chloride were mixed and stirred in a water bath (20 ° C.) for 24 hours to obtain a colorless and transparent solution. When this solution was reprecipitated with 200 ml of acetone, 8.0 g of a white solid was obtained. This solid was dissolved in 100 g of acetic anhydride, 4.9 g of sulfuric acid was added in an ice bath (0 ° C.), and the mixture was stirred for 1 hour. The solution is returned to room temperature, and 13.79 g (50 mmol) of silver carbonate is added thereto, followed by gentle continuous stirring for 3 hours. After filtration, a clear colorless solution was obtained. This solution was concentrated with an evaporator and crystallized overnight in a freezer. The crystallized solid was recovered by suction filtration to obtain 8.1 g of an organic anion silver salt having a polymerizable functional group of the salt monomer (1) as a white solid. The composition of the silver salt of the organic anion having a polymerizable functional group of the obtained salt monomer (1) was confirmed by proton nuclear magnetic resonance spectrum ( ¹ H-NMR).

[Synthesis of Salt Monomer (1)]
4.64 g (30 mmol) of ammonium cation (11) having a polymerizable functional group of the salt monomer (1) is dissolved in 100 ml of methanol / 10 ml of distilled water, and the polymerizable functional group of the salt monomer (1) is dissolved in this solution. A solution obtained by dissolving 7.22 g (30 mmol) of the organic anion (12) having 100 ml of methanol was dropped to react. The reaction proceeded quantitatively. The reaction by-product silver chloride was filtered off, and a colorless and transparent methanol / water solution was recovered. The filtrate was concentrated under reduced pressure using an evaporator to completely remove the solvent, and then the colorless and transparent liquid salt monomer (1) was recovered. The obtained salt monomer (1) was subjected to composition confirmation by proton nuclear magnetic resonance spectrum ( ¹ H-NMR).

[Preparation of Lithium Ion Conducting Electrolyte <LE1>]
Weigh out 0.40 g of the salt monomer (1), 0.40 g of dimethylacrylamide, and 40.20 g of LiClO in a dry argon atmosphere (dew point temperature: −60 ° C. or lower), and stir well to obtain the monomer mixture. Obtained. After sufficiently degassing this, 0.020 g of benzoyl peroxide was added and dissolved uniformly, and then heated at 60 ° C. for 1 hour to obtain a lithium ion conductive electrolyte <LE1>.

[Ion conductivity evaluation of lithium ion conductive electrolyte <LE1>]
About lithium ion conductive electrolyte <LE1> obtained above, the ionic conductivity was measured by the alternating current impedance method. The frequency range during measurement was 50 Hz to 30 MHz, and the voltage was 0.5 V. As a result of the measurement, the ionic conductivity at room temperature (20 ° C.) was 5.1 × 10 ⁻⁴ S / cm.

[Production of positive electrode]
First, lithium carbonate and cobalt carbonate were mixed at a ratio of 0.5 mol: 1 mol. Thereafter, the mixture 900 ° C., to obtain a LiCO ₂ by firing in air.
A positive electrode mixture was prepared by mixing 85% by weight of LiCoO ₂ as a positive electrode active material, 5% by weight of graphite as a conductive agent, and 10% by weight of poly (vinylidene fluoride) as a binder. The positive electrode mixture was dispersed in N-methyl-2-pyrrolidone to obtain a slurry-like positive electrode mixture. This positive electrode mixture was uniformly applied to both surfaces of a 20 μm thick aluminum foil used as a positive electrode current collector, dried, and then compression molded with a roll press to obtain a positive electrode.

[Production of negative electrode]
First, 90% by weight of pulverized graphite powder as a negative electrode active material and 10% by weight of poly (vinylidene fluoride) as a binder are mixed to prepare a negative electrode mixture. -Dispersed in methyl-2-pyrrolidone to prepare a slurry-like negative electrode mixture. This negative electrode mixture was uniformly applied to both surfaces of a 15 μm thick copper foil used as a negative electrode current collector, dried, and then compression molded with a roll press to obtain a negative electrode.

[Production of Lithium Ion Conductive Electrolyte Battery <LB1>]
Next, a monomer electrolyte solution before heating of the lithium ion conductive electrolyte <LE1> is prepared, and the negative electrode and the positive electrode obtained as described above are separated from a separator made of a polyethylene microporous film having a thickness of 25 μm. It was made to contact | adhere through and wound, and it was set as the electrode winding body. While this electrode winding body was enclosed in the exterior film which consists of insulating materials, the monomer solution obtained above was inject | poured in the exterior film. Then, the outer peripheral edge of the exterior film was sealed, the positive electrode terminal and the negative electrode terminal were sandwiched between the openings of the exterior film, and the electrode winding body was sealed in the exterior film under reduced pressure. This was heated at 60 ° C. for 4 hours to polymerize the monomer and to obtain a secondary battery using a polymer solid electrolyte.

[Cycle characteristic evaluation of lithium ion electrolyte battery <LB1>]
After the battery was assembled, constant current voltage charging at 25 ° C. and 500 mA was performed for 2 hours to an upper limit of 4.2 V, and then discharging at 500 mA (1 hour rate discharge) was performed to a final voltage of 2.5 V. Using this as one cycle, 100 cycles of charge / discharge were performed, and the capacity retention rate at the 100th cycle was determined, assuming that the discharge capacity at the first cycle was 100%. The capacity retention rate after 100 cycles was 96%.

(Example 2)
[Synthesis of ammonium cation (21) having polymerizable functional group of salt monomer (2)]
Polymerization of salt monomer (2) as a white solid in the same manner as in Example 1 except that 9.76 g of 1-chloro-10-fluorodecane was used instead of 1-chloro-5-fluoropentane in Example 1. 12.54 g of ammonium cation (21) containing a functional functional group was obtained. Synthesis of the ammonium cation (21) containing a polymerizable functional group of the obtained salt monomer (2) was confirmed by proton nuclear magnetic resonance spectrum ( ¹ H-NMR).

[Synthesis of Organic Anion (22) Having Polymerizable Functional Group of Salt Monomer (2)]
Polymerization of salt monomer (2) as a white solid in the same manner as in Example 1 except that 12.94 g of 1-chloro-1,4-dipentacyclohexane is used instead of 1-chloropentane in Example 1. 13.06g of organic anions (22) containing a functional group were obtained. The organic anion containing a polymerizable functional group of the resulting salt monomer (2) (22) was confirmed synthesized by proton nuclear magnetic resonance spectra ⁽¹ H-NMR).

[Synthesis of Salt Monomer (2)]
Instead of using the ammonium cation (11) having a polymerizable functional group of the salt monomer (1) of Example 1 and the organic anion (12) having a polymerizable functional group of the salt monomer (1), the salt monomer (2) A colorless and transparent liquid salt monomer (2) was prepared in the same manner as in Example 1 except that the ammonium anion (21) having a polymerizable functional group and the organic anion (22) having a polymerizable functional group of the salt monomer (2) were used. Obtained. The composition of the obtained salt monomer (2) was confirmed by proton nuclear magnetic resonance spectrum ( ¹ H-NMR).

[Preparation of lithium ion conductive electrolyte <LE2>]
A lithium ion conductive electrolyte <LE2> was obtained in the same manner as in Example 1 except that the salt monomer (2) was used in place of the salt monomer (1) of Example 1.

[Ion conductivity evaluation of lithium ion conductive electrolyte <LE2>]
The lithium ion conductive electrolyte <LE2> obtained above was measured for ionic conductivity in the same manner as in Example 1. As a result of the measurement, the ionic conductivity at room temperature (20 ° C.) was 6.6 × 10 ⁻⁴ S / cm.

[Production of Lithium Ion Conductive Electrolyte Battery <LB2>]
A lithium ion electrolyte battery <LB2> was obtained in the same manner as in Example 1 except that the lithium ion conductive electrolyte <LE2> was used instead of the lithium ion conductive electrolyte <LE1> of Example 1.

[Cycle characteristic evaluation of lithium ion conductive electrolyte battery <LB2>]
Using the gel-like lithium ion electrolyte battery <LB2> obtained above, the capacity retention rate at the 100th cycle was determined in the same manner as in Example 1. As a result, the capacity retention rate after 100 cycles was 97%. .

(Comparative Example 1)
[Synthesis of Salt Monomer (3)]
Instead of using the ammonium cation (11) having a polymerizable functional group of the salt monomer (1) of Example 1 and the organic anion (12) having a polymerizable functional group of the salt monomer (1), ethyltrimethylammonium methacrylate chloride A white liquid salt monomer (3) was obtained in the same manner as in Example 1 except that 10.385 g and 10.36 g of silver 2-acrylamido-2-methyl-1-propanesulfonate were used. The composition of the obtained salt monomer (3) was confirmed by proton nuclear magnetic resonance spectrum ( ¹ H-NMR).

[Preparation of Lithium Ion Conducting Electrolyte <LE3>]
A lithium ion conductive electrolyte <LE2> was obtained in the same manner as in Example 1 except that the salt monomer (3) was used instead of the salt monomer (1) of Example 1.

[Ion conductivity evaluation of lithium ion conductive electrolyte <LE3>]
For the lithium ion conductive electrolyte <LE5> obtained above, the ionic conductivity was measured in the same manner as in Example 1. As a result of the measurement, the ionic conductivity at room temperature (20 ° C.) was 3.2 × 10 ⁻⁷ S / cm.

[Production of Lithium Ion Conductive Electrolyte Battery <LB3>]
A lithium ion electrolyte battery <LB3> was obtained in the same manner as in Example 1 except that the lithium ion conductive electrolyte <LE3> was used instead of the lithium ion conductive electrolyte <LE1> of Example 1.

[Cycle characteristics evaluation of electrolyte battery <LB3>]
Using the lithium ion conductive electrolyte battery <LB3> obtained above, the capacity retention rate at the 100th cycle was determined in the same manner as in Example 1. As a result, the capacity retention rate after 100 cycles was 32%. .

  The lithium ion conductive electrolyte of the present invention includes primary and secondary batteries, electric double layer capacitors, electrolytes for fuel cell MEAs, binders for secondary battery electrodes, dye-sensitized solar cell electrolytes, gel actuators, and electrical stimulus transmission. It can also be used as a material for artificial nerve axon fillers and other electrochemical devices.

Claims (4)

  A resin composition for an electrolyte comprising a lithium salt, a salt monomer composed of an ammonium cation having a polymerizable functional group and an organic anion having a polymerizable functional group, wherein the salt monomer has a polymerizable functional group. A resin composition for an electrolyte comprising an ammonium cation having a long-chain organic group and an organic anion having a long-chain organic group containing a polymerizable functional group. The resin composition for an electrolyte according to claim 1, wherein the salt monomer is a compound represented by the general formula (1).

(Wherein P ₁ and P ₂ each represent a substituent containing a polymerizable functional group, X represents a group composed of an anionic atom, and R _{1 to} R ₅ each represents a substituted or unsubstituted group, An organic group selected from an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an aralkenyl group and a heterocyclic residue, which may be the same or different from each other, and any one or more of them forms a cyclic structure (However, R ₁ and R ₂ are linear or branched alkyl groups having 5 to 20 carbon atoms.)   The ion conductive electrolyte comprised with the resin composition for electrolytes of Claim 1 or 2.   A secondary battery comprising the ion conductive electrolyte according to claim 3 as a constituent element.