JP2011082001A - Nonaqueous electrolyte and nonaqueous electrolyte battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve battery characteristics when stored under high temperature, and to prevent the generation of gas inside a battery. <P>SOLUTION: A nonaqueous electrolyte containing a chemical compound expressed by Formula (1) is used. In Formula (1), X represents aliphatic of a carbon number 4-18, either alicyclic or aromatic hydrocarbon group (which may contain halogen, phosphorus, silicon, oxygen, and sulfur), or alkoxyl group. R1-R6 are each independently hydrogen, halogen group, alkoxyl group, and aliphatic alkyl group (part or all of hydrogen may be substituted by halogen), and each of R1-R3 and R4-R6 contains two or more halogen atoms. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a nonaqueous electrolyte and a nonaqueous electrolyte battery. More specifically, the present invention relates to a nonaqueous electrolyte containing a nonaqueous solvent and an electrolyte salt and a nonaqueous electrolyte secondary battery using the nonaqueous electrolyte.

In recent years, portable electronic devices such as a camera-integrated VTR (Video Tape Recorder), a mobile phone, or a laptop computer have been widely used, and there is a strong demand for miniaturization, weight reduction, and long life. Accordingly, as a power source, development of a battery, in particular, a secondary battery that is lightweight and capable of obtaining a high energy density is in progress.

  In particular, lithium ion secondary batteries that use lithium (Li) occlusion and release for charge and discharge reactions are highly expected because they can obtain higher energy densities than lead batteries and nickel cadmium batteries. This lithium ion secondary battery is provided with an electrolyte together with a positive electrode and a negative electrode, and has been intensively developed to improve various performances of the non-aqueous electrolyte secondary battery.

  Regarding a lithium ion secondary battery in which a negative electrode is made of a carbonaceous material capable of absorbing and desorbing lithium (Li) ions, as exemplified by an intercalation reaction between graphite layers, for example, Patent Document 1 Such a configuration is disclosed. Patent Document 1 discloses a technique for suppressing deterioration of battery characteristics due to high-temperature storage by using γ-butyrolactone having a relatively high boiling point and a high dielectric constant as a nonaqueous solvent constituting the electrolyte.

  However, when γ-butyrolactone is used, a reductive decomposition reaction occurs at the negative electrode, and the characteristics deteriorate with use of the battery. In addition to this, it has been pointed out that the battery is also deformed by the decomposition and vaporization of the non-aqueous solvent.

  On the other hand, in Patent Document 2, an electrolyte in which a compound that forms a film called SEI (Solid Electrolyte Interface) on a negative electrode during charge and discharge in the initial use of a battery is added in a non-aqueous solvent in advance. By using it, a technique for suppressing reductive decomposition of the nonaqueous solvent on the negative electrode and deformation of the battery has been proposed.

Patent Document 3 proposes a nonaqueous electrolyte and a battery including an aromatic compound having an isocyanate group having a structure represented by (O═C═N—Ar—N═C═O). In the above isocyanate group, Ar represents an aryl group (aromatic carbon chain).

JP 09-92329 A

JP 2003-151623 A

JP 2002-8719 A

  However, when the electrolyte described in Patent Document 2 is used, it is not possible to suppress deterioration of characteristics associated with battery use, and gas generation and battery deformation occur during high-temperature storage. Moreover, when using the electrolyte containing an additive like patent document 3, although the improvement of a high temperature storage characteristic is seen, the further suppression about a further suppression about a non-aqueous solvent and cycling characteristics and a capacity | capacitance is calculated | required. .

  In addition, even in a configuration using a metal can as an exterior member, there is a problem that a large amount of gas is generated when stored at a high temperature, and a safety valve for safety is activated and the battery cannot be used. In addition, when the charge / discharge cycle is repeated, the capacity retention rate rapidly deteriorates, so that it becomes necessary to newly examine constituent materials such as an electrolytic solution. In particular, the cycle characteristics at a temperature higher than room temperature deteriorate more significantly.

  The present invention has been made in view of such problems, and an object thereof is to provide a non-aqueous electrolyte and a non-aqueous electrolyte battery having improved battery characteristics during high-temperature storage.

（式（１）中、Ｘは、炭素数４〜１８の脂肪族炭化水素基（ハロゲン、リン、ケイ素、酸素、硫黄を有していてもよい）、脂環式炭化水素基（ハロゲン、リン、ケイ素、酸素、硫黄を有していてもよい）、芳香族炭化水素基（ハロゲン、リン、ケイ素、酸素、硫黄を有していてもよい）、またはアルコキシル基である。また、Ｒ１〜Ｒ６は各々独立して水素、ハロゲン基、アルコキシル基、脂肪族アルキル基（水素の一部またはすべてをハロゲンで置換してあってもよい）であり、Ｒ１〜Ｒ３とＲ４〜Ｒ６のそれぞれが２以上のハロゲン原子を含む） In order to solve the above-mentioned problem, the first invention is a non-aqueous electrolyte containing a compound represented by the formula (1), an electrolyte salt, and a non-aqueous solvent.

(In the formula (1), X represents an aliphatic hydrocarbon group having 4 to 18 carbon atoms (which may have halogen, phosphorus, silicon, oxygen, sulfur), an alicyclic hydrocarbon group (halogen, phosphorus , Silicon, oxygen, or sulfur), an aromatic hydrocarbon group (which may have halogen, phosphorus, silicon, oxygen, or sulfur), or an alkoxyl group, and R1 to R6. Are each independently hydrogen, a halogen group, an alkoxyl group, or an aliphatic alkyl group (a part or all of hydrogen may be substituted with halogen), and each of R1 to R3 and R4 to R6 is 2 or more Of halogen atoms)

（式（１）中、Ｘは、炭素数４〜１８の脂肪族炭化水素基（ハロゲン、リン、ケイ素、酸素、硫黄を有していてもよい）、脂環式炭化水素基（ハロゲン、リン、ケイ素、酸素、硫黄を有していてもよい）、芳香族炭化水素基（ハロゲン、リン、ケイ素、酸素、硫黄を有していてもよい）、またはアルコキシル基である。また、Ｒ１〜Ｒ６は各々独立して水素、ハロゲン基、アルコキシル基、脂肪族アルキル基（水素の一部またはすべてをハロゲンで置換してあってもよい）であり、Ｒ１〜Ｒ３とＲ４〜Ｒ６のそれぞれが２以上のハロゲン原子を含む） Moreover, 2nd invention is equipped with the positive electrode, the negative electrode, and the nonaqueous electrolyte, and the nonaqueous electrolyte contains the compound shown by Formula (1), electrolyte salt, and a nonaqueous solvent. It is a battery.

(In the formula (1), X represents an aliphatic hydrocarbon group having 4 to 18 carbon atoms (which may have halogen, phosphorus, silicon, oxygen, sulfur), an alicyclic hydrocarbon group (halogen, phosphorus , Silicon, oxygen, or sulfur), an aromatic hydrocarbon group (which may have halogen, phosphorus, silicon, oxygen, or sulfur), or an alkoxyl group, and R1 to R6. Are each independently hydrogen, a halogen group, an alkoxyl group, or an aliphatic alkyl group (a part or all of hydrogen may be substituted with halogen), and each of R1 to R3 and R4 to R6 is 2 or more Of halogen atoms)

（式（２）中、ｎは４以上１８以下の整数を表し、Ｒ１〜Ｒ６は各々独立して水素、ハロゲン基、アルコキシル基、脂肪族炭化水素基（水素の一部またはすべてをハロゲンで置換してあってもよい）であり、Ｒ１〜Ｒ３とＲ４〜Ｒ６のそれぞれが２以上のハロゲンを含む。） In the first and second inventions, the compound represented by the formula (1) is preferably a compound represented by the following formula (2).

(In the formula (2), n represents an integer of 4 or more and 18 or less, and R1 to R6 are each independently hydrogen, halogen group, alkoxyl group, aliphatic hydrocarbon group (part or all of hydrogen is substituted with halogen) And each of R1-R3 and R4-R6 contains two or more halogens.)

  In the first and second inventions, the decomposition of the nonaqueous electrolyte can be suppressed.

  According to this invention, high temperature storage characteristics can be improved, battery swelling of the laminate film type battery after high temperature storage can be suppressed, and the safety valve of the cylindrical battery can be made difficult to operate.

It is sectional drawing which shows the structural example of the secondary battery by the 2nd Embodiment of this invention. It is sectional drawing to which a part of winding electrode body in FIG. 1 was expanded. It is a disassembled perspective view which shows the structural example of the secondary battery by 4th Embodiment of this invention. It is sectional drawing along the II line of the winding electrode body in FIG.

Embodiments of the present invention will be described below with reference to the drawings. The description will be given in the following order.
1. 1st Embodiment (nonaqueous electrolyte used for a nonaqueous electrolyte battery)
2. Second embodiment (an example of a nonaqueous electrolyte battery using a laminate film as an exterior material)
3. Third embodiment (an example of a nonaqueous electrolyte battery using a cylindrical metal can as an exterior material)
4). Other embodiment (modification)

1. First Embodiment A nonaqueous electrolyte according to a first embodiment of the present invention will be described. The nonaqueous electrolyte according to the first embodiment of the present invention is used for an electrochemical device such as a battery.

(1-1) Configuration of Nonaqueous Electrolyte The nonaqueous electrolyte in the present invention includes at least a nonaqueous solvent, an electrolyte salt dissolved in the nonaqueous solvent, and an additive compound composed of a bis (halogenated silyl) alkylene compound. It is out. First, a compound composed of a bis (halogenated silyl) alkylene compound will be described.

[Compound]
As the compound to be mixed with the non-aqueous electrolyte of the present invention, a compound represented by the following formula (1) (hereinafter referred to as a bis (halogenated silyl) alkylene compound as appropriate) is used. Moreover, it can also be used in combination of 2 or more types chosen from the compound represented by Formula (1).

  In the formula (1), X represents an aliphatic hydrocarbon group having 4 to 18 carbon atoms (which may have halogen, phosphorus, silicon, oxygen, or sulfur), an alicyclic hydrocarbon group (halogen, phosphorus, Silicon, oxygen, or sulfur), an aromatic hydrocarbon group (which may have halogen, phosphorus, silicon, oxygen, or sulfur), or an alkoxyl group. R1 to R6 are each independently hydrogen, a halogen group, an alkoxyl group, or an aliphatic alkyl group (part or all of hydrogen may be substituted with halogen), and R1 to R3 and R4 to R6 Each of which contains two or more halogen atoms.

  The aliphatic hydrocarbon group is a linear or branched group having 4 to 18 carbon atoms, the alicyclic hydrocarbon group is a saturated or unsaturated group having 4 to 18 carbon atoms, and the alkoxyl group is an alkyl thereof. It is preferable that the base portion is the above-described aliphatic hydrocarbon group. In the aliphatic hydrocarbon group, alicyclic hydrocarbon group or alkoxyl group, a part or all of hydrogen may be substituted with halogen. As the halogen that can be substituted, chlorine or fluorine is preferred. As the halogen atom contained in two or more of R1 to R3 and R4 to R6, chlorine and fluorine are preferable.

  As the bis (halogenated silyl) alkylene compound, a compound of the following formula (2) is preferable.

  In the formula (2), n represents an integer of 4 or more and 18 or less, and R1 to R6 each independently represent hydrogen, a halogen group, an alkoxyl group, an aliphatic hydrocarbon group (a part or all of hydrogen is substituted with halogen). Each of R1-R3 and R4-R6 contains two or more halogen atoms. As the halogen atom contained in each of R1 to R3 and R4 to R6, chlorine and fluorine are preferable.

  The number of halogens substituted on each silicon atom is preferably 2 or more, and more preferably 3 halogens. When used in electrochemical devices such as secondary batteries, the ability to form a protective film on the electrode surface is increased, and a stronger and more stable protective film is formed, so the decomposition reaction of the nonaqueous electrolyte is further suppressed. Because it is done.

  Here, as the plurality of halogens substituted on one silicon atom, different halogen atoms may be substituted. Moreover, the halogen atom substituted on one silicon atom and the halogen atom substituted on the other silicon atom may be different.

  Specific examples of the bis (halogenated silyl) alkylene compound of the present invention are given below. In addition, the following specific example is an example and this invention is not limited to these.

  Examples of the bis (halogenated silyl) alkylene compound to be mixed with the nonaqueous electrolyte of the present invention include 1,4-bis (trichlorosilyl) benzene, 1,4-bis (trifluorosilyl) benzene, 1,4-bis ( Trichlorosilyl) cyclohexyl, 1,4-bis (trifluorosilyl) cyclohexyl, 1,3-bis (trichlorosilylpropyl) benzene, 1,3-bis (trifluorosilylpropyl) benzene, 1,3-bis (trichlorosiloxy) ) Benzene, 1,3-bis (trifluorosiloxy) benzene, 1,2-bis (trichlorosilyl) ethane, 1,3-bis (trichlorosilyl) propane, 1,4-bis (trichlorosilyl) butane, 1, 5-bis (trichlorosilyl) pentane, 1,6-bis (trichlorosilyl) hexane 1,7-bis (trichlorosilyl) heptane, 1,8-bis (trichlorosilyl) octane, 1,9-bis (trichlorosilyl) nonane, 1,10-bis (trichlorosilyl) decane, 1,12-bis ( Trichlorosilyl) dodecane, 1,18-bis (trichlorosilyl) octadecane, 1,2-bis (trifluorosilyl) ethane, 1,3-bis (trifluorosilyl) propane, 1,4-bis (trifluorosilyl) Butane, 1,5-bis (trifluorosilyl) pentane, 1,6-bis (trifluorosilyl) hexane, 1,7-bis (trifluorosilyl) heptane, 1,8-bis (trifluorosilyl) octane, 1,9-bis (trifluorosilyl) nonane, 1,10-bis (trifluorosilyl) decane, 1,12-bis ( Trifluorosilyl) dodecane, 1,18-bis (trifluorosilyl) octadecane, 1,4-bis (methyldichlorosilyl) benzene, 1,4-bis (methyldifluorosilyl) benzene, 1,4-bis (methyldichloro) Silyl) cyclohexyl, 1,4-bis (methyldifluorosilyl) cyclohexyl, 1,3-bis (methyldichlorosilylpropyl) benzene, 1,3-bis (methyldifluorosilylpropyl) benzene, 1,3-bis (methyldichloro) Siloxy) benzene, 1,3-bis (methyldifluorosiloxy) benzene, 1,2-bis (methyldichlorosilyl) ethane, 1,3-bis (methyldichlorosilyl) propane, 1,4-bis (methyldichlorosilyl) Butane, 1,5-bis (methyldichlorosilyl) pentane, 1,6-bis (methyldichlorosilyl) hexane, 1,7-bis (methyldichlorosilyl) heptane, 1,8-bis (methyldichlorosilyl) octane, 1,9-bis (methyldichlorosilyl) nonane, 1, 10-bis (methyldichlorosilyl) decane, 1,12-bis (methyldichlorosilyl) dodecane, 1,18-bis (methyldichlorosilyl) octadecane, 1,2-bis (methyldifluorosilyl) ethane, 1,3- Bis (methyldifluorosilyl) propane, 1,4-bis (methyldifluorosilyl) butane, 1,5-bis (methyldifluorosilyl) pentane, 1,6-bis (methyldifluorosilyl) hexane, 1,7-bis ( Methyldifluorosilyl) heptane, 1,8-bis (methyldifluorosilyl) octane, 1,9 Bis (methyldifluorosilyl) nonane, 1,10-bis (methyldifluorosilyl) decane, 1,12-bis (methyldifluorosilyl) dodecane, 1,18-bis (methyldifluorosilyl) octadecane, 1,4-bis ( Chlorodimethylsilyl) benzene, 1,4-bis (fluorodimethylsilyl) benzene, 1,4-bis (chlorodimethylsilyl) cyclohexyl, 1,4-bis (fluorodimethylsilyl) cyclohexyl, 1,3-bis (chlorodimethyl) Silylpropyl) benzene, 1,3-bis (fluorodimethylsilylpropyl) benzene, 1,3-bis (chlorodimethylsiloxy) benzene, 1,3-bis (fluorodimethylsiloxy) benzene, 1,2-bis (chlorodimethyl) Silyl) ethane, 1,3-bis (chlorodi) Tilsilyl) propane, 1,4-bis (chlorodimethylsilyl) butane, 1,5-bis (chlorodimethylsilyl) pentane, 1,6-bis (chlorodimethylsilyl) hexane, 1,7-bis (chlorodimethylsilyl) Heptane, 1,8-bis (chlorodimethylsilyl) octane, 1,9-bis (chlorodimethylsilyl) nonane, 1,10-bis (chlorodimethylsilyl) decane, 1,12-bis (chlorodimethylsilyl) dodecane, 1,18-bis (chlorodimethylsilyl) octadecane, 1,2-bis (fluorodimethylsilyl) ethane, 1,3-bis (fluorodimethylsilyl) propane, 1,4-bis (fluorodimethylsilyl) butane, 5-bis (fluorodimethylsilyl) pentane, 1,6-bis (fluorodimethylsilyl) Hexane, 1,7-bis (fluorodimethylsilyl) heptane, 1,8-bis (fluorodimethylsilyl) octane, 1,9-bis (fluorodimethylsilyl) nonane, 1,10-bis (fluorodimethylsilyl) decane, Examples thereof include bis (halogenated silyl) alkylene compounds such as 1,12-bis (fluorodimethylsilyl) dodecane and 1,18-bis (fluorodimethylsilyl) octadecane.

  Among them, 1,3-bis (trichlorosilylpropyl) benzene, 1,3-bis (trifluorosilylpropyl) benzene, 1,6-bis (trichlorosilyl) hexane, 1,6-bis (trifluorosilyl) hexane, 1,8-bis (trichlorosilyl) octane, 1,8-bis (trifluorosilyl) octane, 1,4-bis (trichlorosilyl) butane and 1,4-bis (methyldichlorosilyl) butane are preferred. This is because it is easily available and a high effect can be obtained. Two or more kinds of these additives may be mixed and used.

  As the compound of the formula (2), those having 4 or more carbon atoms in the carbon chain are preferable. Furthermore, it is preferable that the carbon chain constituting the bis (halogenated silyl) alkylene compound is linear. Among these, 1,6-bis (trichlorosilyl) hexane, 1,6-bis (trifluorosilyl) hexane, 1,8-bis (trichlorosilyl) octane, and 1,8-bis (trifluorosilyl) octane are preferable. . This is because it is easily available and a high effect can be obtained. Two or more kinds of these additives may be mixed and used.

  By adding a bis (halogenated silyl) alkylene compound to the non-aqueous electrolyte, the effect of suppressing swelling during high-temperature storage can be obtained. Especially, it is preferable that content of a bis (halogenated silyl) alkylene compound is 0.01 to 5 weight%, and 0.5 to 1 weight% is more preferable. As the amount of the bis (halogenated silyl) alkylene compound increases, the negative electrode film becomes thicker and the film resistance increases, but the battery swelling during high-temperature storage can be sufficiently suppressed. Moreover, when the addition amount of the bis (halogenated silyl) alkylene compound is too small, high cycle characteristics can be maintained, but the remarkable effect of the present invention cannot be expected.

[Nonaqueous solvent]
Non-aqueous solvents include, for example, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, methyl propyl carbonate, γ-butyrolactone, γ-valerolactone, 1 , 2-dimethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, 1,3-dioxolane, 4-methyl-1,3-dioxolane, 1,3-dioxane, 1,4-dioxane, methyl acetate, ethyl acetate, Methyl propionate, ethyl propionate, methyl butyrate, methyl isobutyrate, methyl trimethyl acetate, ethyl trimethyl acetate, acetonitrile, glutaronitrile, adiponitrile, methoxyacetonitrile, 3-methoxypropionitrile, N, N-dimethylformamide, N- Me Tylpyrrolidinone, N-methyloxazolidinone, N, N′-dimethylimidazolidinone, nitromethane, nitroethane, sulfolane, trimethyl phosphate, dimethyl sulfoxide, or the like can be used. This is because, in an electrochemical device such as a battery equipped with a nonaqueous electrolyte, excellent capacity, cycle characteristics and storage characteristics can be obtained. These may be used alone or in combination of two or more.

  Among these, as the non-aqueous solvent, it is preferable to use a solvent containing at least one member selected from the group consisting of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate. This is because a sufficient effect can be obtained. In this case, in particular, ethylene carbonate or propylene carbonate having a high viscosity (high dielectric constant) solvent (for example, relative dielectric constant ε ≧ 30) and dimethyl carbonate having a low viscosity solvent (for example, viscosity ≦ 1 mPa · s). It is preferable to use a mixture containing diethyl carbonate or ethyl methyl carbonate. This is because the dissociation property of the electrolyte salt and the ion mobility are improved, so that a higher effect can be obtained.

  This solvent preferably contains at least one member selected from the group consisting of cyclic carbonates having an unsaturated bond represented by formulas (3) to (5). This is because the chemical stability of the nonaqueous electrolyte is further improved.

  In Formula (3), R7 and R8 are each independently a hydrogen atom, a halogen atom, or an alkyl group having 1 to 12 carbon atoms (which may contain a halogen atom).

  In Formula (4), R9 to R12 are each independently a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 12 carbon atoms (which may contain a halogen atom) or a carbon number having 2 to 12 An alkenyl group, and at least one of R9 to R12 is an alkenyl group having 2 to 12 carbon atoms.

  In Formula (5), R13 is an alkylene group.

  The cyclic carbonate having an unsaturated bond represented by the formula (3) is a vinylene carbonate compound. Examples of the vinylene carbonate compound include vinylene carbonate (1,3-dioxol-2-one), methyl vinylene carbonate (4-methyl-1,3-dioxol-2-one), and ethyl vinylene carbonate (4-ethyl). -1,3-dioxol-2-one), 4,5-dimethyl-1,3-dioxol-2-one, 4,5-diethyl-1,3-dioxol-2-one, 4-fluoro-1, Examples include 3-dioxol-2-one and 4-trifluoromethyl-1,3-dioxol-2-one. These may be used alone or in combination. Among these, vinylene carbonate is preferable. This is because it is easily available and a high effect can be obtained.

  The cyclic carbonate having an unsaturated bond shown in Formula (4) is a vinyl ethylene carbonate compound. Examples of the vinyl carbonate-based compound include vinyl ethylene carbonate (4-vinyl-1,3-dioxolan-2-one), 4-methyl-4-vinyl-1,3-dioxolan-2-one, and 4-ethyl. -4-vinyl-1,3-dioxolan-2-one, 4-n-propyl-4-vinyl-1,3-dioxolan-2-one, 5-methyl-4-vinyl-1,3-dioxolane-2 -One, 4,4-divinyl-1,3-dioxolan-2-one, 4,5-divinyl-1,3-dioxolan-2-one and the like. These may be used alone or in combination. Of these, vinyl ethylene carbonate is preferred. This is because it is easily available and a high effect can be obtained. Of course, as R24 to R27, all may be vinyl groups, all may be allyl groups, or vinyl groups and allyl groups may be mixed.

  The cyclic carbonate having an unsaturated bond represented by the formula (5) is a methylene ethylene carbonate compound. Examples of the methylene ethylene carbonate compound include 4-methylene-1,3-dioxolan-2-one, 4,4-dimethyl-5-methylene-1,3-dioxolan-2-one, and 4,4-diethyl-5. -Methylene-1,3-dioxolan-2-one and the like. These may be used alone or in combination. This methylene ethylene carbonate compound may have one methylene group (the compound shown in the formula (5)) or two methylene groups.

  In addition, as cyclic carbonate which has an unsaturated bond, in addition to what was shown to Formula (3)-Formula (5), carbonate catechol (catechol carbonate) etc. which have a benzene ring may be sufficient.

[Electrolyte salt]
The electrolyte salt contains, for example, one or more light metal salts such as a lithium salt. Examples of the lithium salt include lithium hexafluorophosphate (LiPF ₆ ), lithium tetrafluoroborate (LiBF ₄ ), lithium perchlorate (LiClO ₄ ), lithium hexafluoroarsenate (LiAsF ₆ ), tetra Lithium phenylborate (LiB (C ₆ H ₅ ) ₄ ), lithium methanesulfonate (LiCH ₃ SO ₃ ), lithium trifluoromethanesulfonate (LiCF ₃ SO ₃ ), lithium tetrachloroaluminate (LiAlCl ₄ ), hexafluoride Examples thereof include dilithium silicate (Li ₂ SiF ₆ ), lithium chloride (LiCl), and lithium bromide (LiBr). Among them, at least one selected from the group consisting of lithium hexafluorophosphate (LiPF ₆ ), lithium tetrafluoroborate (LiBF ₄ ), lithium perchlorate (LiClO ₄ ), and lithium hexafluoroarsenate (LiAsF ₆ ). One is preferable, and lithium hexafluorophosphate (LiPF ₆ ) is more preferable. This is because the resistance of the non-aqueous electrolyte is lowered. In particular, it is preferable to use lithium tetrafluoroborate (LiBF ₄ ) together with lithium hexafluorophosphate (LiPF ₆ ). This is because a high effect can be obtained.

  In addition, a so-called gel electrolyte in which a nonaqueous electrolytic solution containing a nonaqueous solvent, an electrolyte salt, and a compound composed of a bis (halogenated silyl) alkylene compound is held in a polymer compound is used. May be.

  The polymer compound in the gel electrolyte is not particularly limited as long as it absorbs a non-aqueous solvent and gels. For example, polyvinylidene fluoride (PVdF) or vinylidene fluoride (VdF) and hexafluoropropylene (HFP) Fluorine polymer compounds such as coalesce, ether polymer compounds such as polyethylene oxide (PEO) or cross-linked products containing polyethylene oxide (PEO), those containing polyacrylonitrile, polypropylene oxide or polymethyl methacrylate as repeating units It is done. Any one of these polymer compounds may be used alone, or two or more thereof may be mixed and used.

In particular, from the viewpoint of redox stability, a fluorine-based polymer compound is desirable, and among them, a copolymer containing vinylidene fluoride and hexafluoropropylene as components is preferable. Furthermore, this copolymer contains monoesters of unsaturated dibasic acids such as monomethylmaleic acid ester, halogenated ethylenes such as ethylene trifluorochloride, cyclic carbonates of unsaturated compounds such as vinylene carbonate, or epoxy group-containing compounds. An acrylic vinyl monomer may be included as a component. This is because higher characteristics can be obtained.

  The nonaqueous electrolyte of the first embodiment includes a bis (halogenated silyl) alkylene compound having a structure represented by the formula (1) together with a nonaqueous solvent and an electrolyte salt. This bis (halogenated silyl) alkylene compound can be used in a non-aqueous electrolyte battery by selecting the number of carbons of the main chain to which a bis (halogenated silyl) group is bonded as shown in Chemical Formula (1) to 4 or more. The decomposition of the solvent and gas generation during high temperature storage can be suppressed, and the deformation of the battery accompanying this can be suppressed. Therefore, it is possible to obtain a nonaqueous electrolyte battery with improved battery characteristics during high temperature storage. The problem of deformation / expansion of the non-aqueous electrolyte battery exterior member and the accompanying deterioration in battery characteristics is not only due to the configuration of the exterior member made of laminate film, but also due to the thin wall of recent containers not only in the configuration of the exterior member made of metal cans. It is considered useful in responding to the transformation.

[Preparation of non-aqueous electrolyte]
The nonaqueous electrolyte of the present invention can be obtained by mixing a predetermined amount of an electrolyte salt with the above-mentioned nonaqueous solvent and then mixing a predetermined amount of the compound represented by the formula (1) for adjustment.

<Effect>
The reason why excellent high-temperature storage characteristics can be obtained by using the nonaqueous electrolytic solution according to the first embodiment of the present invention is not necessarily clear, but is considered as follows. That is, the nonaqueous electrolyte of the present invention contains a bis (halogenated silyl) alkylene compound of the above formula (1), so that stable SEI is formed on the negative electrode by charge and discharge at the initial stage of battery use, and the carbonaceous material It is considered that it is possible to suppress peeling of the resin and decomposition of the cyclic carbonate. Moreover, it is thought that it is adsorb | sucking also on a positive electrode simultaneously with formation of SEI on a negative electrode, and suppressing that the lithium salt and solvent in electrolyte are oxidatively decomposed.

  In the bis (halogenated silyl) alkylene compound of the present invention, the SEI formed by decomposition at the negative electrode contains a large amount of strong inorganic components such as lithium halide, and at the same time, the two positive silyl groups are used for the positive electrode. Since a film can be formed by adsorption, it is considered that the storage characteristics at high temperatures are improved.

2. Second Embodiment A secondary battery according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a sectional configuration of a nonaqueous electrolyte battery according to a second embodiment of the present invention. FIG. 2 shows an enlarged part of the spirally wound electrode body 20 shown in FIG. The nonaqueous electrolyte battery described here is, for example, a lithium ion secondary battery in which the capacity of the negative electrode 22 is expressed based on insertion and extraction of lithium as an electrode reactant.

(2-1) Configuration of Nonaqueous Electrolyte Battery In this nonaqueous electrolyte battery, a positive electrode 21 and a negative electrode 22 are mainly laminated and wound inside a substantially hollow cylindrical battery can 11 via a separator 23. The wound electrode body 20, the pair of insulating plates 12 and 13, and the nonaqueous electrolyte of the present invention are accommodated. The battery structure using the cylindrical battery can 11 is called a cylindrical type.

[Positive electrode]
For example, the positive electrode 21 is obtained by providing a positive electrode active material layer 21B on both surfaces of a positive electrode current collector 21A having a pair of surfaces. However, the positive electrode active material layer 21B may be provided only on one surface of the positive electrode current collector 21A.

  The positive electrode current collector 21A is made of a metal material such as aluminum, nickel, or stainless steel, for example.

  The positive electrode active material layer 21B includes one or more positive electrode materials capable of inserting and extracting lithium as a positive electrode active material, and a positive electrode binder or a positive electrode conductive material as necessary. Other materials such as agents may be included.

As a positive electrode material capable of inserting and extracting lithium, for example, a lithium-containing compound is preferable. This is because a high energy density can be obtained. Examples of the lithium-containing compound include a composite oxide containing lithium and a transition metal element, and a phosphate compound containing lithium and a transition metal element. Especially, what contains at least 1 sort (s) of the group which consists of cobalt, nickel, manganese, and iron as a transition metal element is preferable. This is because a higher voltage can be obtained. The chemical formula thereof is represented by, for example, Li _x M1O ₂ or Li _y M2PO ₄ . In the formula, M1 and M2 represent one or more transition metal elements. The values of x and y vary depending on the charge / discharge state, and are generally 0.05 ≦ x ≦ 1.10 and 0.05 ≦ y ≦ 1.10.

Examples of the composite oxide containing lithium and a transition metal element include lithium cobalt composite oxide (Li _x CoO ₂ ), lithium nickel composite oxide (Li _x NiO ₂ ), and lithium nickel cobalt composite oxide (Li _x Ni). _1-z Co _z O ₂ (z <1)), lithium nickel cobalt manganese composite oxide (Li _x Ni _(1-vw) Co _v Mn _w O ₂ (v + w <1)), or lithium having a spinel structure Manganese composite oxide (LiMn ₂ O ₄ ) and the like can be mentioned. Among these, a complex oxide containing cobalt is preferable. This is because a high capacity can be obtained and excellent cycle characteristics can be obtained. Examples of the phosphoric acid compound containing lithium and a transition metal element include a lithium iron phosphate compound (LiFePO ₄ ) or a lithium iron manganese phosphate compound (LiFe _1-u Mn _u PO ₄ (u <1)). Is mentioned.

  In addition, examples of positive electrode materials capable of occluding and releasing lithium include oxides such as titanium oxide, vanadium oxide and manganese dioxide, disulfides such as titanium disulfide and molybdenum sulfide, and niobium selenide. And a conductive polymer such as sulfur, polyaniline or polythiophene.

  The positive electrode material capable of inserting and extracting lithium may be other than the above. Moreover, the positive electrode material illustrated above may be mixed 2 or more types by arbitrary combinations.

  Examples of the positive electrode binder include synthetic rubbers such as styrene butadiene rubber, fluorine rubber or ethylene propylene diene, and polymer materials such as polyvinylidene fluoride. These may be single and multiple types may be mixed.

  Examples of the positive electrode conductive agent include carbon materials such as graphite, carbon black, acetylene black, and ketjen black. These may be single and multiple types may be mixed. The positive electrode conductive agent may be a metal material or a conductive polymer as long as it is a conductive material.

[Negative electrode]
In the negative electrode 22, for example, a negative electrode active material layer 22B is provided on both surfaces of a negative electrode current collector 22A having a pair of surfaces. However, the negative electrode active material layer 22B may be provided only on one surface of the negative electrode current collector 22A.

  The negative electrode current collector 22A is made of, for example, a metal material such as copper, nickel, or stainless steel.

  The negative electrode active material layer 22B includes one or more negative electrode materials capable of inserting and extracting lithium as a negative electrode active material, and a negative electrode binder or a negative electrode conductive material as necessary. Other materials such as agents may be included. At this time, the chargeable capacity of the negative electrode material capable of inserting and extracting lithium is preferably larger than the discharge capacity of the positive electrode. Note that details regarding the negative electrode binder and the negative electrode conductive agent are the same as, for example, the positive electrode binder and the positive electrode conductive agent, respectively.

  Examples of the negative electrode material capable of inserting and extracting lithium include a carbon material. Examples of the carbon material include graphitizable carbon, non-graphitizable carbon having a (002) plane spacing of 0.37 nm or more, and graphite having a (002) plane spacing of 0.34 nm or less. It is. More specifically, there are pyrolytic carbons, cokes, glassy carbon fibers, organic polymer compound fired bodies, activated carbon or carbon blacks. Among these, the cokes include pitch coke, needle coke, petroleum coke and the like. The organic polymer compound fired body is obtained by firing and carbonizing a phenol resin, a furan resin, or the like at an appropriate temperature. The carbon material is preferable because the change in crystal structure associated with insertion and extraction of lithium is very small, so that a high energy density can be obtained, and excellent cycle characteristics can be obtained. The shape of the carbon material may be any of a fibrous shape, a spherical shape, a granular shape, and a scale shape.

  As the negative electrode material capable of inserting and extracting lithium in addition to the carbon material described above, for example, it can store and release lithium and constitute at least one of a metal element and a metalloid element The material which has as an element is mentioned. This is because a high energy density can be obtained. Such a negative electrode material may be a single element, an alloy or a compound of a metal element or a metalloid element, and may have one or two or more phases thereof at least in part. The “alloy” in the present invention includes an alloy containing one or more metal elements and one or more metalloid elements in addition to an alloy composed of two or more metal elements. Further, the “alloy” may contain a nonmetallic element. This structure includes a solid solution, a eutectic (eutectic mixture), an intermetallic compound, or one in which two or more of them coexist.

  Examples of the metal element or metalloid element described above include a metal element or metalloid element capable of forming an alloy with lithium. Specifically, magnesium (Mg), boron (B), aluminum (Al), gallium (Ga), indium (In), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), Examples thereof include bismuth (Bi), cadmium (Cd), silver (Ag), zinc (Zn), hafnium (Hf), zirconium (Zr), yttrium (Y), palladium (Pd), and platinum (Pt). Among these, at least one of silicon and tin is preferable, and silicon is more preferable. This is because a high energy density can be obtained because the ability to occlude and release lithium is large.

  Examples of the negative electrode material having at least one of silicon and tin include at least a part of a simple substance, an alloy or a compound of silicon, a simple substance, an alloy or a compound of tin, or one or more phases thereof. The material which has in is mentioned.

  As an alloy of silicon, for example, as a second constituent element other than silicon, tin (Sn), nickel (Ni), copper (Cu), iron (Fe), cobalt (Co), manganese (Mn), zinc ( One containing at least one of the group consisting of Zn), indium (In), silver (Ag), titanium (Ti), germanium (Ge), bismuth (Bi), antimony (Sb) and chromium (Cr) Can be mentioned. Examples of tin alloys include silicon (Si), nickel (Ni), copper (Cu), iron (Fe), cobalt (Co), and manganese (Mn) as second constituent elements other than tin (Sn). , Zinc (Zn), indium (In), silver (Ag), titanium (Ti), germanium (Ge), bismuth (Bi), antimony (Sb) and chromium (Cr). Including.

  Examples of the tin compound or the silicon compound include those containing oxygen (O) or carbon (C), and include the second constituent element described above in addition to tin (Sn) or silicon (Si). You may go out.

  In particular, as a negative electrode material containing at least one of silicon (Si) and tin (Sn), for example, tin (Sn) is used as the first constituent element, and in addition to the tin (Sn), the second configuration What contains an element and a 3rd structural element is preferable. Of course, this negative electrode material may be used together with the negative electrode material described above. The second constituent element is cobalt (Co), iron (Fe), magnesium (Mg), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu ), Zinc (Zn), gallium (Ga), zirconium (Zr), niobium (Nb), molybdenum (Mo), silver (Ag), indium (In), cerium (Ce), hafnium (Hf), tantalum (Ta) ), Tungsten (W), bismuth (Bi), and silicon (Si). The third constituent element is at least one selected from the group consisting of boron (B), carbon (C), aluminum (Al), and phosphorus (P). This is because the cycle characteristics are improved by including the second element and the third element.

  Among them, tin (Sn), cobalt (Co) and carbon (C) are included as constituent elements, and the content of carbon (C) is in the range of 9.9 mass% to 29.7 mass%, tin (Sn) In addition, a CoSnC-containing material in which the ratio of cobalt (Co) to the total of cobalt (Co) (Co / (Sn + Co)) is in the range of 30% by mass to 70% by mass is preferable. This is because in such a composition range, a high energy density is obtained and an excellent cycle characteristic is obtained.

  This SnCoC-containing material may further contain other constituent elements as necessary. Examples of other constituent elements include silicon (Si), iron (Fe), nickel (Ni), chromium (Cr), indium (In), niobium (Nb), germanium (Ge), titanium (Ti), and molybdenum. (Mo), aluminum (Al), phosphorus (P), gallium (Ga), bismuth (Bi), and the like are preferable, and two or more of them may be included. This is because the capacity characteristic or cycle characteristic is further improved.

  The SnCoC-containing material has a phase containing tin (Sn), cobalt (Co), and carbon (C), and this phase has a low crystallinity or an amorphous structure. preferable. In the SnCoC-containing material, it is preferable that at least a part of carbon as a constituent element is bonded to a metal element or a metalloid element as another constituent element. The decrease in cycle characteristics is thought to be due to aggregation or crystallization of tin (Sn) or the like, but such aggregation or crystallization is suppressed when carbon is combined with other elements. It is.

  Examples of the measurement method for examining the bonding state of elements include X-ray photoelectron spectroscopy (XPS). In this XPS, in the apparatus calibrated so that the 4f orbit (Au4f) peak of gold atom is obtained at 84.0 eV, the peak of 1s orbit (C1s) of carbon appears at 284.5 eV in the case of graphite. . Moreover, if it is surface contamination carbon, it will appear at 284.8 eV. In contrast, when the charge density of the carbon element is high, for example, when carbon is bonded to a metal element or a metalloid element, the C1s peak appears in a region lower than 284.5 eV. That is, when the peak of the synthetic wave of C1s obtained for the SnCoC-containing material appears in a region lower than 284.5 eV, a metal in which at least a part of carbon (C) contained in the SnCoC-containing material is another constituent element Bonded with element or metalloid element.

  In XPS, for example, the peak of C1s is used to correct the energy axis of the spectrum. Usually, since surface-contaminated carbon exists on the surface, the C1s peak of the surface-contaminated carbon is set to 284.8 eV, which is used as an energy standard. In XPS, the waveform of the peak of C1s is obtained as a form including the peak of surface contamination carbon and the peak of carbon in the SnCoC-containing material. For example, by analyzing using commercially available software, the surface contamination The carbon peak and the carbon peak in the SnCoC-containing material are separated. In the waveform analysis, the position of the main peak existing on the lowest bound energy side is used as the energy reference (284.8 eV).

  Further, examples of the negative electrode material capable of inserting and extracting lithium include metal oxides or polymer compounds capable of inserting and extracting lithium. Examples of the metal oxide include iron oxide, ruthenium oxide, and molybdenum oxide. Examples of the polymer compound include polyacetylene, polyaniline, and polypyrrole.

  The negative electrode material capable of inserting and extracting lithium may be other than the above. Moreover, 2 or more types of said negative electrode materials may be mixed by arbitrary combinations.

  The negative electrode active material layer 22B may be formed by any of, for example, a gas phase method, a liquid phase method, a thermal spray method, a baking method, or a coating method, or a combination of two or more thereof. When the negative electrode active material layer 22B is formed using a vapor phase method, a liquid phase method, a thermal spraying method or a firing method, or two or more of these methods, the negative electrode active material layer 22B and the negative electrode current collector 22A include It is preferable to alloy at least a part of the interface. Specifically, the constituent elements of the negative electrode current collector 22A diffuse into the negative electrode active material layer 22B at the interface, the constituent elements of the negative electrode active material layer 22B diffuse into the negative electrode current collector 22A, or the constituent elements thereof It is preferable that they diffuse to each other. This is because breakage due to expansion and contraction of the negative electrode active material layer 22B due to charging / discharging can be suppressed, and electronic conductivity between the negative electrode active material layer 22B and the negative electrode current collector 22A can be improved. .

  As the vapor phase method, for example, physical deposition method or chemical deposition method, specifically, vacuum evaporation method, sputtering method, ion plating method, laser ablation method, thermal chemical vapor deposition (CVD) Or plasma chemical vapor deposition. As the liquid phase method, a known method such as electroplating or electroless plating can be used. The firing method is, for example, a method in which a particulate negative electrode active material is mixed with a binder and dispersed in a solvent and then heat treated at a temperature higher than the melting point of the binder. A known method can also be used for the firing method, for example, an atmospheric firing method, a reactive firing method, or a hot press firing method.

[Separator]
The separator 23 separates the positive electrode 21 and the negative electrode 22 and allows lithium ions to pass through while preventing a short circuit of current due to contact between the two electrodes. The separator 23 is made of, for example, a porous film made of a synthetic resin such as polytetrafluoroethylene, polypropylene, or polyethylene, or a porous film made of ceramic, and these two or more kinds of porous films are laminated. It may be what was done. The separator 23 is impregnated with the electrolytic solution according to the first embodiment described above.

  In this nonaqueous electrolyte battery, when charged, for example, lithium ions are extracted from the positive electrode 21 and inserted in the negative electrode 22 through the electrolytic solution impregnated in the separator 23. On the other hand, when discharging is performed, for example, lithium ions are released from the negative electrode 22 and inserted into the positive electrode 21 through the electrolytic solution impregnated in the separator 23.

  According to this non-aqueous electrolyte battery, when the capacity of the negative electrode 22 is expressed based on insertion and extraction of lithium, the electrolytic solution according to the first embodiment described above is provided. The decomposition reaction of the liquid is suppressed. Therefore, it is possible to improve the cycle characteristics and the storage characteristics particularly during high temperature use. In this case, when the content of the sulfone compound in the non-aqueous solvent is 0.01% by weight or more and 2% by weight or less, a higher effect can be obtained.

  In this nonaqueous electrolyte battery, in particular, the negative electrode 22 is capable of inserting and extracting lithium, such as silicon or tin, which is advantageous for increasing the capacity, and a material having at least one of a metal element and a metalloid element. It is preferable to include. This is because the effect of improving cycle characteristics and storage characteristics is great. That is, in this nonaqueous electrolyte battery, when the negative electrode 22 includes a negative electrode material such as silicon or tin, a higher effect can be obtained than when other negative electrode materials such as a carbon material are included.

[Nonaqueous electrolyte]
As the non-aqueous electrolyte, the non-aqueous electrolyte of the first embodiment can be used.

(2-2) Manufacturing method of nonaqueous electrolyte battery [Manufacture of positive electrode]
First, the positive electrode 21 is produced. First, a positive electrode active material, a positive electrode binder, and a positive electrode conductive agent are mixed to form a positive electrode mixture, and then dispersed in an organic solvent to obtain a paste-like positive electrode mixture slurry. Subsequently, the positive electrode mixture slurry is uniformly applied to both surfaces of the positive electrode current collector 21A by a doctor blade or a bar coater and dried. Finally, the positive electrode active material layer 21B is formed by compressing and molding the coating film with a roll press or the like while heating as necessary. In this case, compression molding may be repeated a plurality of times.

[Manufacture of negative electrode]
Next, the negative electrode 22 is produced. First, after preparing a negative electrode current collector 22A made of electrolytic copper foil or the like, a plurality of negative electrode active material particles are formed by depositing a negative electrode material on both surfaces of the negative electrode current collector 22A by a vapor phase method such as a vapor deposition method. To do. After this, if necessary, by forming an oxide-containing film by a liquid phase method such as a liquid phase deposition method, or by forming a metal material by a liquid phase method such as an electrolytic plating method, or by forming both, The negative electrode active material layer 22B is formed.

  Moreover, you may produce the negative electrode 22 by the procedure similar to a positive electrode. That is, first, a negative electrode material, a negative electrode binder, and, if necessary, a negative electrode conductive agent are mixed to form a negative electrode mixture, which is then dispersed in an organic solvent to obtain a paste-like negative electrode mixture slurry. To do. Subsequently, the negative electrode mixture slurry is uniformly applied to both surfaces of the negative electrode current collector 22A by a doctor blade or a bar coater and dried. Finally, the negative electrode active material layer 21B is formed by compression-molding the coating film with a roll press or the like while heating as necessary.

[Assembly of non-aqueous electrolyte battery]
The non-aqueous electrolyte battery is assembled as follows. First, the positive electrode lead 25 is attached to the positive electrode current collector 21A by welding or the like, and the negative electrode lead 26 is attached to the negative electrode current collector 22A by welding or the like. Subsequently, after the positive electrode 21 and the negative electrode 22 are stacked and wound through the separator 23 to produce the wound electrode body 20, the center pin 24 is inserted into the winding center. Subsequently, the wound electrode body 20 is housed in the battery can 11 while being sandwiched between the pair of insulating plates 12 and 13, the tip of the positive electrode lead 25 is welded to the safety valve mechanism 15, and the tip of the negative electrode lead 26 is attached. Weld to battery can 11.

  Subsequently, the electrolytic solution according to the first embodiment described above is injected into the battery can 11 and impregnated in the separator 23. Finally, the battery lid 14, the safety valve mechanism 15, and the heat sensitive resistance element 16 are fixed to the opening end of the battery can 11 by caulking through the gasket 17. Thereby, the nonaqueous electrolyte battery shown in FIGS. 1 and 2 is completed.

<Effect>
In the non-aqueous electrolyte battery according to the second embodiment of the present invention, the non-aqueous electrolyte contains the compound represented by the formula (1) or the formula (2), so that it is described in the first embodiment. Thus, even if a nonaqueous electrolyte battery repeats charging / discharging, the decomposition reaction of a nonaqueous electrolyte is suppressed. Therefore, the operation of the safety valve mechanism can be suppressed and the battery characteristics can be improved.

3. Third Embodiment A nonaqueous electrolyte battery according to a third embodiment of the present invention will be described. FIG. 3 shows an exploded perspective configuration of a nonaqueous electrolyte battery according to a third embodiment of the present invention, and FIG. 4 is an enlarged cross-sectional view taken along line II of the spirally wound electrode body 30 shown in FIG. As shown.

(3-1) Configuration of Nonaqueous Electrolyte Battery This nonaqueous electrolyte battery is, for example, a lithium ion nonaqueous electrolyte battery similar to the nonaqueous electrolyte battery according to the second embodiment. In the member 40, the wound electrode body 30 to which the positive electrode lead 31 and the negative electrode lead 32 are attached, and the nonaqueous electrolyte of the present invention are accommodated. The battery structure using the film-shaped exterior member 40 is called a laminate film type.

  For example, the positive electrode lead 31 and the negative electrode lead 32 are led out in the same direction from the inside of the exterior member 40 toward the outside. The positive electrode lead 31 is made of, for example, a metal material such as aluminum, and the negative electrode lead 32 is made of, for example, a metal material such as copper, nickel, or stainless steel. These metal materials are, for example, in a thin plate shape or a mesh shape.

[Exterior material]
The exterior member 40 is made of, for example, an aluminum laminated film in which a nylon film, an aluminum foil, and a polyethylene film are bonded together in this order. The exterior member 40 has, for example, a structure in which outer edges of two rectangular aluminum laminate films are bonded to each other by fusion or an adhesive so that the polyethylene film faces the wound electrode body 30. ing.

  An adhesive film 41 is inserted between the exterior member 40 and the positive electrode lead 31 and the negative electrode lead 32 to prevent intrusion of outside air. The adhesion film 41 is made of a material having adhesion to the positive electrode lead 31 and the negative electrode lead 32. Examples of such a material include polyolefin resins such as polyethylene, polypropylene, modified polyethylene, and modified polypropylene.

  In addition, the exterior member 40 may be comprised with the laminated film which has another laminated structure instead of the above-mentioned aluminum laminated film, and may be comprised with polymer films or metal films, such as a polypropylene.

[Wound electrode body]
FIG. 4 illustrates a cross-sectional configuration along the line II of the spirally wound electrode body 30 illustrated in FIG. The wound electrode body 30 is obtained by laminating and winding a positive electrode 33 and a negative electrode 34 via a separator 35 and an electrolyte 36, and an outermost peripheral portion thereof is protected by a protective tape 37.

  In the positive electrode 33, for example, a positive electrode active material layer 33B is provided on both surfaces of a positive electrode current collector 33A. The negative electrode 34 is, for example, provided with a negative electrode active material layer 34B on both surfaces of a negative electrode current collector 34A, and the negative electrode active material layer 34B is disposed so as to face the positive electrode active material layer 33B. The configurations of the positive electrode current collector 33A, the positive electrode active material layer 33B, the negative electrode current collector 34A, the negative electrode active material layer 34B, and the separator 35 are respectively the positive electrode current collector 21A, the positive electrode active material layer 21B, and the second embodiment. The configurations of the negative electrode current collector 22A, the negative electrode active material layer 22B, and the separator 23 are the same.

[Nonaqueous electrolyte]
The nonaqueous electrolyte in the third embodiment is a gel electrolyte that includes the electrolytic solution according to the first embodiment described above and a polymer compound that holds the electrolytic solution. The gel electrolyte is preferable because high ion conductivity (for example, 1 mS / cm or more at room temperature) is obtained and liquid leakage is prevented.

  In the gel electrolyte layer 36 made of a gel electrolyte, the nonaqueous solvent of the electrolytic solution is a wide concept including not only a liquid nonaqueous solvent but also one having ion conductivity capable of dissociating an electrolyte salt. Therefore, when a polymer compound having ion conductivity is used, the polymer compound is also included in the non-aqueous solvent. Instead of the gel electrolyte layer 36 in which the nonaqueous electrolytic solution is held by the polymer compound, the nonaqueous electrolytic solution may be used as it is. In this case, the separator 35 is impregnated with the nonaqueous electrolytic solution.

(3-2) Manufacturing Method of Nonaqueous Electrolyte Battery This nonaqueous electrolyte battery is manufactured by, for example, the following three types of manufacturing methods (first to third manufacturing methods).

[First manufacturing method]
In the first manufacturing method, first, the positive electrode active material layer 33B is formed on both surfaces of the positive electrode current collector 33A, for example, by the same procedure as the manufacturing procedure of the positive electrode 21 and the negative electrode 22 of the second embodiment described above. Thus, the positive electrode 33 is manufactured. Further, the negative electrode active material layer 34B is formed on both surfaces of the negative electrode current collector 34A to produce the negative electrode 34.

  Subsequently, a precursor solution containing an electrolytic solution according to the first embodiment, a polymer compound, and a solvent is prepared and applied to the positive electrode 33 and the negative electrode 34, and then the solvent is volatilized to form the gel electrolyte layer 36. To do. Subsequently, the positive electrode lead 31 is attached to the positive electrode current collector 33A, and the negative electrode lead 32 is attached to the negative electrode current collector 34A.

  Subsequently, the positive electrode 33 and the negative electrode 34 on which the gel electrolyte layer 36 is formed are stacked via the separator 35 and then wound in the longitudinal direction, and a protective tape 37 is adhered to the outermost peripheral portion of the wound electrode body 30. Is made. Finally, for example, after the wound electrode body 30 is sandwiched between two film-shaped exterior members 40, the outer edge portions of the exterior member 40 are bonded to each other by heat fusion or the like, so that the wound electrode body 30 is Encapsulate. At this time, the adhesion film 41 is inserted between the positive electrode lead 31 and the negative electrode lead 32 and the exterior member 40. Thereby, the nonaqueous electrolyte battery shown in FIGS. 3 and 4 is completed.

[Second manufacturing method]
In the second manufacturing method, first, the positive electrode lead 31 is attached to the positive electrode 33 and the negative electrode lead 32 is attached to the negative electrode 34. Subsequently, after the positive electrode 33 and the negative electrode 34 are laminated and wound via the separator 35, a protective tape 37 is adhered to the outermost peripheral portion thereof, and a wound body that is a precursor of the wound electrode body 30. Is made.

  Subsequently, after sandwiching the wound body between the two film-shaped exterior members 40, the remaining outer peripheral edge except for the outer peripheral edge on one side is adhered by heat fusion or the like, thereby forming a bag-shaped exterior The wound body is accommodated in the member 40. Subsequently, an electrolyte composition containing an electrolytic solution, a monomer that is a raw material of the polymer compound, a polymerization initiator, and other materials such as a polymerization inhibitor as necessary is prepared to form a bag-shaped exterior member. After injecting into the inside of 40, the opening of the exterior member 40 is sealed by heat fusion or the like. Finally, the gel electrolyte layer 36 is formed by thermally polymerizing the monomer to obtain a polymer compound. Thereby, a nonaqueous electrolyte battery is completed.

[Third production method]
In the third manufacturing method, a wound body is formed by forming a wound body in the same manner as in the second manufacturing method described above except that the separator 35 coated with the polymer compound on both sides is used first. 40 is housed inside.

  Examples of the polymer compound applied to the separator 35 include a polymer containing vinylidene fluoride as a component, that is, a homopolymer, a copolymer, or a multi-component copolymer. Specifically, polyvinylidene fluoride, binary copolymers containing vinylidene fluoride and hexafluoropropylene as components, and ternary copolymers containing vinylidene fluoride, hexafluoropropylene and chlorotrifluoroethylene as components. Such as coalescence.

  The polymer compound may contain one or more other polymer compounds together with the polymer containing vinylidene fluoride as a component. Subsequently, after the electrolytic solution is prepared and injected into the exterior member 40, the opening of the exterior member 40 is sealed by heat fusion or the like. Finally, the exterior member 40 is heated while applying a load, and the separator 35 is brought into close contact with the positive electrode 33 and the negative electrode 34 through the polymer compound. As a result, the electrolytic solution is impregnated into the polymer compound, and the polymer compound is gelled to form the gel electrolyte layer 36, thereby completing the nonaqueous electrolyte battery.

  In the third manufacturing method, the swelling of the nonaqueous electrolyte battery is suppressed as compared with the first manufacturing method. Further, in the third manufacturing method, compared to the second manufacturing method, the monomer or non-aqueous solvent which is a raw material of the polymer compound hardly remains in the gel electrolyte layer 36, and the polymer compound forming step Is well controlled. Thereby, in the third manufacturing method, sufficient adhesion is obtained between the positive electrode 33, the negative electrode 34, the separator 35, and the gel electrolyte layer 36.

<Effect>
In the nonaqueous electrolyte battery according to the third embodiment of the present invention, since the nonaqueous electrolyte contains the compound represented by the formula (1) or the formula (2), as described in the first embodiment. Even if the nonaqueous electrolyte battery repeats charging and discharging, the decomposition reaction of the nonaqueous electrolyte is suppressed. Therefore, gas generation inside the battery and battery swelling associated therewith can be suppressed, and battery characteristics can be improved.

4). Other Embodiments The present invention is not limited to the above-described embodiments of the present invention, and various modifications and applications are possible without departing from the spirit of the present invention. For example, the usage application of the compounds represented by the formulas (1) and (2) of the present invention is not necessarily limited to the electrolytic solution. In addition, the usage of the electrolytic solution according to the first embodiment of the present invention is not necessarily limited to a non-aqueous electrolyte battery, and may be an electrochemical device (for example, a capacitor) other than the non-aqueous electrolyte battery. .

Specific examples of the present invention will be described in detail below, but the present invention is not limited thereto.
In addition, the compound added to the nonaqueous electrolyte used in the following Examples and Comparative Examples is as follows.

As a bis (halogenated silyl) alkylene compound,
Compound (A): 1,8-bis (trichlorosilyl) octane compound (B): 1,8-bis (trifluorosilyl) octane compound (C): 1,6-bis (trichlorosilyl) hexane compound (D) : 1,6-bis (trifluorosilyl) hexane compound (E): 1,4-bis (trichlorosilyl) butane compound (F): 1,4-bis (methyldichlorosilyl) butane compound (G): 1, 6-bis (chlorodimethylsilyl) hexane compound (H): 1,6-bis (fluorodimethylsilyl) hexane compound (I): 1,4-bis (chlorodimethylsilyl) butane compound (J): 1,4- Bis (fluorodimethylsilyl) butane compound (K): 1,2-bis (chlorodimethylsilyl) ethane compound (L): 1,2-bis (fluorodimethylsilyl) Ethane was used.

In addition, as an alkyl halogenated silane compound,
Compound (M): Hexyltrichlorosilane Compound (N): Hexyltrifluorosilane was used.

The structural formulas of the above-mentioned compounds (A) to (N) are as follows.

[Example 1]
<Example 1-1>
The laminate film type secondary battery shown in FIGS. 3 and 4 was produced by the following procedure.

[Production of positive electrode]
First, 94 parts by weight of lithium cobaltate (LiCoO ₂ ) as a positive electrode active material, 3 parts by weight of graphite as a conductive agent, and 3 parts by weight of polyvinylidene fluoride (PVdF) as a binder were homogeneously mixed to form N-methyl. Pyrrolidone was added to obtain a positive electrode mixture slurry.

  Next, this positive electrode mixture slurry is uniformly coated on both sides of an aluminum foil having a thickness of 10 μm, dried and compression-molded, and a positive electrode active material layer having a thickness of 30 μm per side (volume density of the active material layer) : 3.40 g / cc). This was cut into a shape having a width of 50 mm and a length of 300 mm to obtain a positive electrode.

[Production of negative electrode]
97 parts by weight of MCMB (mesocarbon microbeads) graphite as a negative electrode active material and 3 parts by weight of PVdF as a binder were homogeneously mixed, and N-methylpyrrolidone was added to obtain a negative electrode mixture slurry.

  Next, this negative electrode mixture slurry was uniformly applied on both sides of a 10 μm thick copper foil serving as a negative electrode current collector, dried and pressed at 200 MPa to form a negative electrode active material layer having a thickness of 30 μm per side. This was cut into a shape having a width of 50 mm and a length of 300 mm to obtain a negative electrode.

  As the separator, a 7 μm-thick microporous polyethylene film coated with 2 μm each of polyvinylidene fluoride was used.

[Preparation of non-aqueous electrolyte]
A mixed solution was prepared by adding 1% by weight of vinylene carbonate (VC) to ethylene carbonate (EC): diethyl carbonate (DEC) = 3: 7 (weight ratio). The dissolved lithium hexafluorophosphate (LiPF ₆₎ as a 1.0 mol / kg as an electrolyte salt. Further, the bis (halogenated silyl) alkylene compound (A) was mixed and dissolved at a concentration of 0.005% by weight to obtain a nonaqueous electrolytic solution.

[Assembly of non-aqueous electrolyte battery]
After winding the positive electrode and the negative electrode through a separator, the positive electrode and the negative electrode were put into a bag-shaped exterior member made of an aluminum laminate film, and then 2 g of a non-aqueous electrolyte was injected. Thereafter, the bag was heat-sealed and sealed to produce a laminated film type non-aqueous electrolyte battery.

<Example 1-2>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-1 except that the amount of compound A mixed was 0.01 wt%.

<Example 1-3>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-1 except that the amount of compound A mixed was 0.05 wt%.

<Example 1-4>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-1 except that the amount of compound A mixed was 0.5 wt%.

<Example 1-5>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-1 except that the amount of compound A mixed was 1% by weight.

<Example 1-6>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-1 except that the amount of compound A mixed was 5 wt%.

<Example 1-7>
A laminated film type non-aqueous electrolyte battery was produced in the same manner as in Example 1-1 except that the amount of compound A mixed was 6% by weight.

<Comparative Example 1-1>
A laminated film type non-aqueous electrolyte battery was produced in the same manner as in Example 1-1 except that Compound A was not added.

[Evaluation of non-aqueous electrolyte battery]
(A) Swelling amount during high-temperature storage The nonaqueous electrolyte batteries of each Example and Comparative Example were charged with a constant current at a current of 1 C in a 23 ° C. environment, and were charged at a constant voltage when the battery voltage reached 4.2V. When the total charging time was 3 hours, charging was terminated. Thereafter, discharging was performed at a current of 1 C, and the discharging was terminated when the battery voltage reached 3.0V. In this way, charge and discharge were performed for 2 cycles, and the battery thickness before storage was measured.

  Next, after charging under the same conditions as described above in a 23 ° C. environment, each non-aqueous electrolyte battery with a battery voltage of 4.2 V is stored in a constant temperature bath at 85 ° C. for 24 hours, and the battery after storage The thickness was measured. Subsequently, the difference between the battery thickness before storage and the battery thickness after storage was determined as the amount of swelling during high temperature storage. “1C” is a current value at which the theoretical capacity can be discharged in one hour.

(B) Cycle characteristics The nonaqueous electrolyte batteries of the examples and comparative examples were charged with a constant current at a current of 1 C in a 23 ° C environment, and switched to a constant voltage charge when the battery voltage reached 4.2 V. Charging was terminated when the charging time reached 3 hours. Thereafter, discharging was performed at a current of 1 C, and the discharging was terminated when the battery voltage reached 3.0V. The discharge capacity at this time was measured as the initial capacity.

  Subsequently, 300 cycles of charge and discharge were performed under the above-described charge and discharge conditions, and the discharge capacity at the 300th cycle was measured. Then, from {(discharge capacity at the 300th cycle / initial capacity) × 100}, the capacity retention rate at the 300th cycle was calculated and used as the cycle characteristics.

  Table 1 below shows the results of the evaluation.

  As shown in Table 1, compared with Comparative Example 1-1 in which the compound (A) was not added, each example in which the compound (A) was added had a reduced amount of battery swelling at high temperatures. Moreover, it turned out that the amount of swelling at the time of high temperature storage becomes small, so that there are many compounds (A). On the other hand, the more the compound (A), the lower the cycle characteristics. Therefore, it was found that the addition amount is more preferably 0.01% by weight to 5% by weight, and particularly preferably 0.5% by weight to 1% by weight.

[Example 2]
In Example 2, the effect of adding the compound of the present invention was confirmed by changing the type of the compound added to the non-aqueous electrolyte.

<Example 2-1>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4.

<Example 2-2>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (B).

<Example 2-3>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (C).

<Example 2-4>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (D).

<Example 2-5>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (E).

<Example 2-6>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (F).

<Comparative Example 2-1>
A laminate film type non-aqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound (A) was not added.

<Comparative Example 2-2>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (G).

<Comparative Example 2-3>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (H).

<Comparative Example 2-4>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (I).

<Comparative Example 2-5>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (J).

<Comparative Example 2-6>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (K).

<Comparative Example 2-7>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (L).

<Comparative Example 2-8>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (M).

<Comparative Example 2-9>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4 except that the compound added to the nonaqueous electrolyte was changed to the compound (N).

[Evaluation of non-aqueous electrolyte battery]
(A) Measurement of swelling amount at high temperature storage For each non-aqueous electrolyte battery of each example and comparative example, the battery swelling amount at high temperature storage was measured in the same manner as in Example 1.

  Table 2 below shows the results of the evaluation.

  As shown in Table 2, Comparative Example 2-1 in which the bis (halogenated silyl) alkylene compound was not added to the nonaqueous electrolytic solution had a very large battery expansion of 2.73 mm. In addition, the main chain is made of aliphatic carbon having 4 to 18 carbon atoms, and each of R1 to R3 and R4 to R6 contains one halogen, compound (G), compound (H), compound (I), compound (J ), Comparative Example 2-2 to Comparative Example 2-7 using Compound (K) and Compound (L), and Comparative Example 2 using an alkylhalogenated silane compound having only one halogenated silyl group −8 and Comparative Example 2-9 had a battery swelling amount of about 1.7 mm to the same level as Comparative Example 2-1, and the effect of suppressing the battery swelling was small.

  On the other hand, in Example 2-1, in which the main chain is composed of aliphatic carbon having 4 to 18 carbon atoms, and each of R1 to R3 and R4 to R6 contains three halogens, The amount of battery expansion was as small as 1.0 mm or less, and the effect of suppressing battery expansion was confirmed. Similarly, in Examples 2-2 to 2-6 using the compound (B), the compound (C), the compound (D), the compound (E), and the compound (F), the amount of battery swelling during high-temperature storage is also similar. It was found to be very small, about 1.0 mm or 1.0 mm or less.

  That is, it is preferable that the number of halogens substituted on the silicon atom is larger. When the number of halogens substituted on silicon is small, or the number of carbon atoms of the compound (K) and the compound (L) aliphatic hydrocarbon group is small, such as the compounds (G) to (L), the temperature is high. Gas generation due to storage could not be sufficiently suppressed, and the amount of battery swelling increased. When a compound having only one silyl halide group such as the compound (M) and the compound (N) was used, the effect of suppressing battery swelling was not observed. As the compound to be added, it was found that the compound (B) and the compound (D) are particularly preferable since the effect of suppressing swelling is large.

[Example 3]
In Example 3, the effect of adding the compound of the present invention was confirmed by changing the negative electrode active material used in the nonaqueous electrolyte battery.

<Example 3-1>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 1-4, except that silicon was used instead of the graphite material as the negative electrode active material. Silicon used as the negative electrode active material can occlude and release lithium in the same manner as the graphite material.

  In the case of forming a negative electrode active material layer using silicon, after preparing a negative electrode current collector (thickness = 15 μm) made of an electrolytic copper foil, negative electrodes are formed on both sides of the negative electrode current collector by an electron beam evaporation method. A negative electrode was fabricated by depositing silicon as an active material to form a negative electrode active material layer. In the case of forming this negative electrode active material layer, the negative electrode active material particles were formed through 10 deposition steps so that the negative electrode active material particles had a 10-layer structure. At this time, the thickness (total thickness) of the negative electrode active material particles on one side of the negative electrode current collector was 6 μm.

  The negative electrode thus obtained was cut into a shape having a width of 50 mm and a length of 300 mm to obtain a negative electrode for a laminate film type battery. For this secondary battery, the thickness of the positive electrode active material layer was adjusted so that lithium metal did not deposit on the negative electrode during full charge.

<Example 3-2>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 3-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (B).

<Example 3-3>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 3-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (C).

<Example 3-4>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 3-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (D).

<Comparative Example 3-1>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 3-1, except that the compound A was not added.

[Evaluation of non-aqueous electrolyte battery]
(A) Measurement of swelling amount at high temperature storage For each non-aqueous electrolyte battery of each example and comparative example, the battery swelling amount at high temperature storage was measured in the same manner as in Example 1.

  Table 3 below shows the results of the evaluation.

  As shown in Table 3, even when silicon was used as the negative electrode active material, the compound (A) described above was compared with Comparative Example 3-1, in which no bis (halogenated silyl) alkylene compound was added to the nonaqueous electrolytic solution. ), The compound (B), the compound (C) and the compound (D), respectively, were able to obtain a battery swelling suppressing effect remarkably.

[Example 4]
Also in Example 4, the negative electrode active material used for the nonaqueous electrolyte battery was changed as in Example 3, and the effect of adding the compound of the present invention was confirmed.

<Example 4-1>
A laminate film type non-aqueous electrolyte battery was produced in the same manner as in Example 1-4 except that a SnCoC-containing material was used instead of the graphite material as the negative electrode active material. The SnCoC-containing material used as the negative electrode active material can occlude and release lithium similarly to the graphite material.

  In the case of forming a negative electrode active material layer using a SnCoC-containing material, first, cobalt powder and tin powder were alloyed to form a cobalt-tin alloy powder, and then carbon powder was added and dry mixed. Subsequently, 10 g of the above mixture was set together with about 400 g of steel balls having a diameter of 9 mm in a reaction vessel of a planetary ball mill manufactured by Ito Seisakusho. Subsequently, after replacing the inside of the reaction vessel with an argon atmosphere, an operation for 10 minutes and a pause for 10 minutes at a rotation speed of 250 revolutions per minute were repeated until the total operation time reached 20 hours. Subsequently, after the reaction vessel was cooled to room temperature and the SnCoC-containing material was taken out, the coarse powder was removed through a 280 mesh sieve.

  80 parts by weight of SnCoC-containing material as a negative electrode active material, 8 parts by weight of PVdF as a binder, 11 parts by weight of graphite and 1 part by weight of acetylene black as a conductive agent are mixed homogeneously, and N-methylpyrrolidone is added. A mixture slurry was obtained.

  Next, this negative electrode mixture slurry was uniformly applied on both sides of a 15 μm thick copper foil serving as a negative electrode current collector, dried and then pressed with a roll press to form a negative electrode active material layer having a thickness of 50 μm per side. . This was cut into a shape having a width of 50 mm and a length of 300 mm to obtain a negative electrode.

<Example 4-2>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 4-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (B).

<Example 4-3>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 4-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (C).

<Example 4-4>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 4-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (D).

<Comparative Example 4-1>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 4-1, except that the compound A was not added.

[Evaluation of non-aqueous electrolyte battery]
(A) Measurement of swelling amount at high temperature storage For each non-aqueous electrolyte battery of each example and comparative example, the battery swelling amount at high temperature storage was measured in the same manner as in Example 1.

  Table 4 below shows the results of the evaluation.

  As shown in Table 4, even when a SnCoC-containing material was used as the negative electrode active material, the compound described above was compared with Comparative Example 4-1, in which no bis (halogenated silyl) alkylene compound was added to the non-aqueous electrolyte. In Examples 4-1 to 4-4 using (A), the compound (B), the compound (C), and the compound (D), the battery swelling suppression effect was remarkably obtained.

  As can be seen from Comparative Example 3-1 and Comparative Example 4-1, when the SnCoC-containing material is used as the negative electrode active material, the amount of battery swelling tends to increase compared to the case where silicon is used as the negative electrode active material. is there. However, as can be seen from, for example, Example 3-1 and Example 4-1, the amount of battery swelling in Example 4-1 was reduced by adding the compound (A). That is, the use of the SnCoC-containing material as the negative electrode active material was able to obtain a more remarkable swelling suppression effect. Similarly, when the compound (B), the compound (C) and the compound (D) are used, the nonaqueous electrolyte battery using the SnCoC-containing material as the negative electrode active material can obtain a more remarkable effect. It was.

[Example 5]
In Example 5, a cylindrical nonaqueous electrolyte battery using a nonaqueous electrolytic solution to which the compound of the present invention was added was produced, and the effect of adding the compound of the present invention was confirmed.

<Example 5-1>
[Production of positive electrode]
First, 91 parts by weight of lithium cobaltate as a positive electrode active material, 6 parts by weight of graphite as a conductive agent, and 3 parts by weight of polyvinylidene fluoride as a binder are added, and N-methylpyrrolidone is added to mix the positive electrode mixture slurry. Got. Next, this positive electrode mixture slurry was uniformly applied to both surfaces on an aluminum foil having a thickness of 12 μm, dried, and then compression molded with a roll press to form a positive electrode active material layer. After that, an aluminum positive electrode lead was welded and attached to one end of the positive electrode current collector.

[Production of negative electrode]
Further, 97 parts by weight of artificial graphite powder as a negative electrode active material and 3 parts by weight of polyvinylidene fluoride as a binder were mixed, and N-methylpyrrolidone was added to obtain a negative electrode mixture slurry. Next, this negative electrode mixture slurry was uniformly applied on both sides of a 15 μm thick copper foil serving as a negative electrode current collector, dried, and then compression molded with a roll press to form a negative electrode active material layer. . After that, a nickel negative electrode lead was attached to one end of the negative electrode current collector.

[Preparation of non-aqueous electrolyte]
A mixed solution was prepared by adding 1% by weight of vinylene carbonate (VC) to ethylene carbonate (EC): dimethyl carbonate (DMC) = 3: 7 (weight ratio). The dissolved lithium hexafluorophosphate (LiPF ₆₎ as a 1.2 mol / kg as an electrolyte salt. Furthermore, the compound (A) was mixed and dissolved at a concentration of 0.5% by weight to obtain a nonaqueous electrolytic solution.

  Subsequently, a positive electrode, a separator made of a microporous polypropylene film (thickness 25 μm), and a negative electrode are laminated in this order, and then wound many times in a spiral shape, and then the winding end portion is fixed with an adhesive tape. Thus, a wound electrode body was formed. Subsequently, after preparing a nickel-plated iron battery can, the wound electrode body was sandwiched between a pair of insulating plates, the negative electrode lead was welded to the battery can and the positive electrode lead was welded to the safety valve mechanism, The wound electrode body was housed inside the battery can. Subsequently, an electrolytic solution was injected into the battery can by a reduced pressure method.

<Example 5-2>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (B).

<Example 5-3>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (C).

<Example 5-4>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (D).

<Comparative Example 5-1>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound (A) was not added.

<Comparative Example 5-2>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (G).

<Comparative Example 5-3>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (H).

<Comparative Example 5-4>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (I).

<Comparative Example 5-5>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (J).

<Comparative Example 5-6>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (K).

<Comparative Example 5-7>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (L).

<Comparative Example 5-8>
A laminate film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (M).

<Comparative Example 5-9>
A laminated film type nonaqueous electrolyte battery was produced in the same manner as in Example 5-1, except that the compound added to the nonaqueous electrolyte was changed to the compound (N).

[Evaluation of non-aqueous electrolyte battery]
(B) Measurement of safety valve operating time during high temperature storage The nonaqueous electrolyte batteries of the examples and comparative examples were charged at a constant current of 0.5 C in a 23 ° C. environment, and the battery voltage reached 4.2V. Switching to constant voltage charging at that time, the charging was terminated when the total charging time was 3 hours. Thereafter, discharging was performed at a current of 0.5 C, and the discharging was terminated when the battery voltage reached 3.0V. Thus, 2 cycles of charging / discharging were performed, and the discharge capacity before storage was measured.

  Next, after charging under the same conditions as described above in a 23 ° C. environment, each nonaqueous electrolyte battery with a battery voltage of 4.2 V is stored in a constant temperature bath at 95 ° C. until the shutoff valve is activated. Asked for time. “0.5 C” is a current value at which the theoretical capacity can be discharged in 2 hours.

  Table 5 below shows the results of the evaluation.

  As shown in Table 5, in Comparative Examples 5-8 and 5-9 using the compound (M) having only one silyl halide group and the compound (N), a bis (halogenated silyl) alkylene compound was used. Was the same safety valve operating time as Comparative Example 5-1, which was not added to the non-aqueous electrolyte. That is, in Comparative Example 5-8 and Comparative Example 5-9, the effect of suppressing gas generation in the cylindrical nonaqueous electrolyte battery was not obtained. Further, in Comparative Examples 5-2 to 5-7, the safety valve operating time was changed from 48 hours to 59 hours, which was the same as that of Comparative Example 5-1.

  On the other hand, in Example 5-1 to Example 5-4, it turns out that the safety valve operation time is as long as 64 to 68 hours, and the gas generation suppression effect is significantly obtained as compared with each comparative example. It was.

  Although the embodiments and examples of the present invention have been described above, the present invention is not limited to the above-described embodiments of the present invention, and various modifications and applications are possible without departing from the spirit of the present invention. Is possible. For example, in the above-described embodiments and examples, the secondary battery having a winding structure has been described as a specific example, but the present invention includes a battery element in which a positive electrode and a negative electrode are stacked and folded in a zigzag manner, or The present invention can be similarly applied to a secondary battery having another stacked structure in which a positive electrode and a negative electrode are stacked.

  Moreover, although the above-mentioned embodiment and Example demonstrated the case where a film-shaped exterior member was used, you may use the exterior member of a can. In that case, the shape may be a cylindrical shape, a square shape, a coin shape or a button shape.

  Furthermore, in the above-described embodiments and examples, the case where lithium is used for the electrode reaction has been described. However, other alkali metals such as sodium (Na) or potassium (K), or alkaline earth such as magnesium or calcium (Ca). The present invention can also be applied to the case where other light metals such as a similar metal or aluminum are used, and the same effect can be obtained. Further, lithium metal may be used as the negative electrode active material.

  In the above-described embodiments and examples, the type of nonaqueous electrolyte battery includes a lithium ion nonaqueous electrolyte battery in which the capacity of the negative electrode is expressed based on insertion and extraction of lithium, and the capacity of the negative electrode is precipitation of lithium. A lithium metal non-aqueous electrolyte battery represented on the basis of dissolution has been described. However, the present invention is not necessarily limited to these. That is, for example, the present invention uses a material capable of inserting and extracting lithium as the negative electrode active material, and the chargeable capacity of the negative electrode material capable of inserting and extracting lithium is greater than the discharge capacity of the positive electrode. The same applies to the nonaqueous electrolyte battery in which the capacity of the negative electrode includes the capacity associated with insertion and extraction of lithium and the capacity associated with precipitation and dissolution of lithium, and is represented by the sum of these capacities. Applicable.

  In the above-described embodiments and examples, the case where the battery structure is a laminate film type and the case where the battery element has a winding structure have been described as examples, but the present invention is not limited thereto. The nonaqueous electrolyte battery of the present invention can be similarly applied to a case where the battery element has other battery structures such as a square shape, a coin shape and a button shape, and a case where the battery element has another structure such as a laminated structure. is there.

  In the above-described embodiments and examples, the case where lithium is used as the electrode reactant has been described, but the present invention is not limited to this. For example, other group 1 elements such as sodium (Na) or potassium (K), group 2 elements such as magnesium (Mg) or calcium (Ca), and other light metals such as aluminum may be used. In these cases, the negative electrode material described in the above embodiment can be used as the negative electrode active material.

  In the above-described embodiments and examples, the appropriate range derived from the results of the examples is described for the content of the sulfone compound, but the description may be outside the above-described range. It does not completely deny sex. In other words, the appropriate range described above is a particularly preferable range for obtaining the effects of the present invention, and the content may slightly deviate from the above-described ranges as long as the effects of the present invention are obtained.

DESCRIPTION OF SYMBOLS 11 ... Battery can 12, 13 ... Insulating plate 14 ... Battery cover 15 ... Safety valve mechanism 16 ... Heat sensitive resistance element 17 ... Gasket 20 ... Winding electrode body 21 ... -Positive electrode 21A ... Positive electrode current collector 21B ... Positive electrode active material layer 22 ... Negative electrode 22A ... Negative electrode current collector 22B ... Negative electrode active material layer 23 ... Separator 24 ... Center pin 25 ... Positive electrode lead 26 ... Negative electrode lead

Claims (10)

A non-aqueous electrolyte containing a compound represented by the formula (1), an electrolyte salt, and a non-aqueous solvent.

(In the formula (1), X represents an aliphatic hydrocarbon group having 4 to 18 carbon atoms (which may have halogen, phosphorus, silicon, oxygen, sulfur), an alicyclic hydrocarbon group (halogen, phosphorus , Silicon, oxygen, or sulfur), an aromatic hydrocarbon group (which may have halogen, phosphorus, silicon, oxygen, or sulfur), or an alkoxyl group, and R1 to R6. Are each independently hydrogen, a halogen group, an alkoxyl group, or an aliphatic alkyl group (a part or all of hydrogen may be substituted with halogen), and each of R1 to R3 and R4 to R6 is 2 or more Of halogen atoms) The nonaqueous electrolyte according to claim 1, wherein the compound represented by the formula (1) is a compound represented by the formula (2).

(In the formula (2), n represents an integer of 4 or more and 18 or less, and R1 to R6 are each independently hydrogen, halogen group, alkoxyl group, aliphatic hydrocarbon group (part or all of hydrogen is substituted with halogen) And each of R1-R3 and R4-R6 contains two or more halogens.) 3. The non-aqueous solution according to claim 1, wherein the amount of the compound represented by the formula (1) and / or the compound represented by the formula (2) is 0.01% by weight or more and 5% by weight or less based on the total amount. Electrolytes. The nonaqueous electrolyte according to claim 3, wherein the halogen atom contained in each of R1 to R3 and R4 to R6 in the formula (1) and the formula (2) is chlorine or fluorine. The compound represented by the above formula (2) is 1,6-bis (trichlorosilyl) hexane, 1,6-bis (trifluorosilyl) hexane, 1,8-bis (trichlorosilyl) octane, 1,8-bis. The nonaqueous electrolyte according to claim 3, which is at least one of (trifluorosilyl) octane. A positive electrode, a negative electrode, and a non-aqueous electrolyte;
The non-aqueous electrolyte is
A nonaqueous electrolyte battery comprising a compound represented by formula (1), an electrolyte salt, and a nonaqueous solvent.

(In the formula (1), X represents an aliphatic hydrocarbon group having 4 to 18 carbon atoms (which may have halogen, phosphorus, silicon, oxygen, sulfur), an alicyclic hydrocarbon group (halogen, phosphorus , Silicon, oxygen, or sulfur), an aromatic hydrocarbon group (which may have halogen, phosphorus, silicon, oxygen, or sulfur), or an alkoxyl group, and R1 to R6. Are each independently hydrogen, a halogen group, an alkoxyl group, or an aliphatic alkyl group (a part or all of hydrogen may be substituted with halogen), and each of R1 to R3 and R4 to R6 is 2 or more Of halogen atoms) The nonaqueous electrolyte battery according to claim 6, wherein the compound represented by the formula (1) is a compound represented by the formula (2).

(In the formula (2), n represents an integer of 4 or more and 18 or less, and R1 to R6 are each independently hydrogen, halogen group, alkoxyl group, aliphatic hydrocarbon group (part or all of hydrogen is substituted with halogen) And each of R1-R3 and R4-R6 contains two or more halogens.) The amount of the compound represented by the above formula (1) and / or the compound represented by the above formula (2) is 0.01% by weight or more and 5% by weight or less of the whole nonaqueous electrolyte. The nonaqueous electrolyte battery described. The nonaqueous electrolyte battery according to claim 8, wherein the positive electrode, the negative electrode, and the nonaqueous electrolyte are packaged with a laminate film. The nonaqueous electrolyte battery according to claim 8, wherein the positive electrode, the negative electrode, and the nonaqueous electrolyte are packaged with a metal can.

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