JP4884021B2 - Method for manufacturing electrode for secondary battery - Google Patents

Description

  The present invention relates to an electrode for a secondary battery characterized in that a conductive material-containing radical material mixed with a conductive material is contained in the electrode, and an output characteristic, particularly a low-temperature characteristic, using the electrode, and energy. The present invention relates to a secondary battery having a high density.

With the spread of portable electronic devices such as portable personal computers and handy video cameras in recent years, non-aqueous electrolyte secondary batteries having high voltage and high energy density have been widely used as power sources. Also, from the viewpoint of environmental problems, battery cars and hybrid cars using electric power as a part of power have been put into practical use.
Among these, lithium ion secondary batteries using a lithium-containing metal oxide for the positive electrode and a carbon material for the negative electrode are used in various electronic devices as secondary batteries having a high energy density. However, since this lithium ion secondary battery is accompanied by a lithium ion insertion / release reaction during charging / discharging, the battery performance is significantly lowered when a large current is passed. Therefore, when used for a small electronic device, a long charging time is required.

  On the other hand, a secondary battery using a radical material typified by poly (2,2,6,6-tetramethylpiperidinoxymethacrylate) (PTMA) as a positive electrode utilizes an ion adsorption / desorption reaction. Since a large current can flow and the cycle characteristics are excellent, it can be used for portable electronic devices and electric vehicles.

  However, in a secondary battery using a radical material such as poly (2,2,6,6-tetramethylpiperidinoxymethacrylate) (PTMA) as an electrode, the radical material itself has almost no conductivity, so that As shown in Document 1, a large amount of conductive material must be added to the radical material when preparing the electrode paste, ensuring the conductivity of the electrode, excellent output characteristics, and high energy density. The battery has never been obtained.

Therefore, various methods have been proposed in order to improve the conductivity of the electrode. Patent Document 2 discloses that carbon paper is sandwiched between a positive electrode material and a current collector to improve conductivity. Although a certain effect can be seen by this countermeasure, in addition to the electrode layer containing a large amount of a normal conductive material, a conductive material layer is formed, which has the drawback of reducing the energy density.
Further, Patent Document 3 proposes that a polymer type hindered amine compound having a hindered amine structure incorporated in (meth) acrylic acid ester is added to the positive electrode, negative electrode or separator. However, hindered amine compounds incorporated in (meth) acrylic acid ester type polymers have high solubility in electrolytes at low molecular weights, and positive electrode materials with high molecular weight powders blended with carbon have a wide range of effects. There wasn't.

JP 2004-200059 A JP 2005-228705 A JP 2001-210314 A

  Therefore, an object of the present invention is to use an electrode for a secondary battery that can secure a conductivity of the electrode, obtain a secondary battery having excellent output characteristics, particularly low temperature characteristics, and high energy density, and the electrode. It is to provide a secondary battery.

  As a result of various investigations in view of the present situation, the present inventors have mixed conductive materials in the liquid phase immediately after synthesizing the radical material, and by taking out the radical material and the conductive material by a method such as coprecipitation, The secondary battery can increase the bonding surface between the radical material and the conductive material to ensure conductivity. When this conductive material-containing radical material is placed in the battery, the secondary battery has excellent output characteristics, particularly low temperature characteristics, and high energy density. It was found that can be obtained.

The present invention has been made based on the above findings, and immediately after the radical material is synthesized by a polymerization reaction in the liquid phase, the conductive material-containing radical material obtained by mixing the conductive material in the liquid phase is contained in the electrode. An electrode for a secondary battery is provided.
The present invention also provides a secondary battery characterized in that, in a secondary battery having at least a positive electrode, a negative electrode, and an electrolyte as constituent elements, the positive electrode is the electrode for a secondary battery.

  According to the present invention, it is possible to provide a secondary battery that is excellent in output characteristics, particularly low-temperature characteristics, and has a high energy density.

The secondary battery electrode of the present invention and the secondary battery using the electrode will be described in detail below.
First, the electrode for a secondary battery of the present invention will be described.
The conductive material-containing radical material used in the present invention is synthesized by a method such as anionic polymerization in the liquid phase, and immediately after that, the conductive material is mixed in the liquid phase and co-precipitated as a uniform mixture. By taking out, it can obtain as a uniform composition efficiently.

  Examples of the radical material include a nitroxyl radical compound having a structure represented by the following chemical formula (1), a nitroxyl radical compound represented by the following general formula (2), and a nitro having a structural unit represented by the following general formula (3). Preferable examples include a xyl radical compound, a nitroxyl radical compound which is a piperidyl group-containing high molecular weight polymer or copolymer having a structure represented by the following general formula (4) or the following general formula (5).

（上式においてＲ₁ 及びＲ₂ は、各々独立に、置換もしくは無置換のアルキル基、置換もしくは無置換のアルケニル基、置換もしくは無置換のシクロアルキル基、置換もしくは無置換の芳香族基、置換もしくは無置換のアラルキル基、ヒドロキシル基、置換もしくは無置換のアルコキシ基、置換もしくは無置換のアシル基、カルボキシル基、置換もしくは無置換のアルコキシカルボニル基、シアノ基、置換もしくは無置換のアミノ基、置換もしくは無置換のアリールオキシ基、置換もしくは無置換のアリールオキシカルボニル基、ニトロ基、ニトロソ基、ハロゲン原子、又は水素原子である。但し、Ｒ₁ 又はＲ₂ が脂肪族基を含む場合、該脂肪族基は、飽和又は不飽和であってよく、置換又は無置換であってよく、鎖状、環状又は分岐状であってよく、１個以上の酸素、窒素、硫黄、ケイ素、リン、ホウ素又はハロゲン原子を含んでもよい。Ｒ₁ 又はＲ₂ が芳香族基を含む場合、該芳香族基は、置換又は無置換であってよく、１個以上の酸素、窒素、硫黄、ケイ素、リン、ホウ素又はハロゲン原子を含んでもよい。Ｒ₁ 又はＲ₂ がヒドロキシル基を含む場合、該ヒドロキシル基は金属原子と塩を形成していてもよい。Ｒ₁ 又はＲ₂ がアルコキシ基、アルコキシカルボニル基、アミノ基のいずれかを含む場合、これら置換基は、置換又は無置換であってよく、１個以上の酸素、窒素、硫黄、ケイ素、リン、ホウ素又はハロゲン原子を含んでもよい。Ｒ₁ とＲ₂ は同一であっても異なっていてもよく、Ｒ₁ とＲ₂ とで環を形成してもよい。）

(In the above formula, R ₁ and R ₂ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aromatic group, substituted Or unsubstituted aralkyl group, hydroxyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted acyl group, carboxyl group, substituted or unsubstituted alkoxycarbonyl group, cyano group, substituted or unsubstituted amino group, substituted Or an unsubstituted aryloxy group, a substituted or unsubstituted aryloxycarbonyl group, a nitro group, a nitroso group, a halogen atom, or a hydrogen atom, provided that when R ₁ or R ₂ contains an aliphatic group, The group may be saturated or unsaturated, substituted or unsubstituted, chained, cyclic or branched. Well, if one or more oxygen, nitrogen, sulfur, silicon, phosphorus, may contain boron or halogen atom .R ₁ or R ₂ contains an aromatic group, aromatic group is a substituted or unsubstituted It may contain one or more oxygen, nitrogen, sulfur, silicon, phosphorus, boron or halogen atoms, and when R ₁ or R ₂ contains a hydroxyl group, the hydroxyl group forms a salt with the metal atom. When R ₁ or R ₂ contains any one of an alkoxy group, an alkoxycarbonyl group, and an amino group, these substituents may be substituted or unsubstituted, and one or more oxygen, nitrogen, sulfur, (It may contain a silicon, phosphorus, boron or halogen atom. R ₁ and R ₂ may be the same or different, and R ₁ and R ₂ may form a ring.)

（式中、Ｘは、少なくとも1 つの脂肪族基、芳香族基、ヒドロキシル基、アルコキシ基、アルデヒド基、カルボキシル基、アルコキシカルボニル基、シアノ基、アミノ基、ニトロ基、ニトロソ基、ハロゲン原子、もしくは水素原子を含む置換基である。但し、Ｘが脂肪族基を含む場合、該脂肪族基は、飽和又は不飽和であってもよく、置換又は無置換であってもよく、鎖状、環状又は分岐状であってもよく、１個以上の酸素、窒素、硫黄、ケイ素、リン、ホウ素又はハロゲン原子を含んでもよい。Ｘがヒドロキシル基を含む場合、該ヒドロキシル基は金属原子と塩を形成していてもよい。Ｘがアルコキシ基、アルデヒド基、カルボキシル基、アルコキシカルボニル基、シアノ基、アミノ基、ニトロ基、ニトロソ基のいずれかを含む場合、これら置換基は、置換又は無置換であってよく、１個以上の酸素、窒素、硫黄、ケイ素、リン、ホウ素又はハロゲン原子を含んでもよい。Ｘが環を形成してもよい。）

Wherein X is at least one aliphatic group, aromatic group, hydroxyl group, alkoxy group, aldehyde group, carboxyl group, alkoxycarbonyl group, cyano group, amino group, nitro group, nitroso group, halogen atom, or A substituent containing a hydrogen atom, provided that when X contains an aliphatic group, the aliphatic group may be saturated or unsaturated, substituted or unsubstituted, chained, cyclic Or it may be branched and may contain one or more oxygen, nitrogen, sulfur, silicon, phosphorus, boron or halogen atoms, and when X contains a hydroxyl group, the hydroxyl group forms a salt with the metal atom. When X contains any of an alkoxy group, an aldehyde group, a carboxyl group, an alkoxycarbonyl group, a cyano group, an amino group, a nitro group, and a nitroso group, Substituents may be substituted or unsubstituted, one or more oxygen, nitrogen, sulfur, silicon, phosphorus, may contain boron or halogen atom .X may form a ring.)

（式中、Ｒ₄ は、水素原子、メチル基又は−ＣＯＯＬｉであり、Ｒ₅ 及びＲ₆ は、各々独立に、水素原子又はメチル基を示し、Ｒ₇ は、水素原子、アルカリ金属、炭素原子数１〜５０のアルキル基、炭素原子数１〜５０のアルケニル基、炭素原子数１〜５０のアラルキル基、炭素原子数１〜５０のハロゲン原子で置換されたアルキル基を示す。Ｘ₁ 及びＸ₂ は、各々独立に、直接結合、−ＣＯ−、−ＣＯＯ−、−ＣＯＮＲ₈ −、−Ｏ−、−Ｓ−、置換基を有してもよいアルキレン基、置換基を有してもよいアリーレン基、又はこれらの基の二つ以上を結合させた２価の基を示す。Ｒ₈ は、水素原子又は炭素原子数１〜１８のアルキル基を示す。ｎは３０以上の数を、ｍは０又は正の数を表す。）

(In the formula, R ₄ represents a hydrogen atom, a methyl group or —COOLi, R ₅ and R ₆ each independently represent a hydrogen atom or a methyl group, and R ₇ represents a hydrogen atom, an alkali metal, or a carbon atom. the number 1 to 50 alkyl group, an alkenyl group having a carbon number of 1 to 50, an aralkyl group having 1 to 50 carbon atom, an alkyl group substituted with a halogen atom having 1 to 50 carbon atom .X ₁ and X ₂ may each independently have a direct bond, —CO—, —COO—, —CONR ₈ —, —O—, —S—, an alkylene group which may have a substituent, or a substituent. An arylene group or a divalent group formed by bonding two or more of these groups, R ₈ represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, n represents a number of 30 or more, m Represents 0 or a positive number.)

（式中、Ｒ₉ は、水素原子又はメチル基を示し、Ｒ₁₀は、水素原子、アルカリ金属、炭素原子数１〜３０のアルキル基、炭素原子数１〜３０のアルケニル基、炭素原子数１〜３０のアリールアルキル基、炭素原子数１〜３０のハロゲンで置換されたアルキル基を示す。Ｘ₂ は、直接結合、−ＣＯ−、−ＣＯＯ−、−ＣＯＮＲ₈ −、−Ｏ−、−Ｓ−、置換基を有してもよいアルキレン基、置換基を有してもよいアリーレン基、およびこれらの基の二つ以上を結合させた２価の基を示す。Ｒ₈ は、水素原子又は炭素原子数１〜１８のアルキル基を示す。ｎは３０以上の数を示す。）

(In the formula, R ₉ represents a hydrogen atom or a methyl group, and R ₁₀ represents a hydrogen atom, an alkali metal, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 1 to 30 carbon atoms, or 1 carbon atom. An arylalkyl group having ˜30, or an alkyl group substituted with a halogen having 1 to 30 carbon atoms, X ₂ is a direct bond, —CO—, —COO—, —CONR ₈ —, —O—, —S; -Represents an alkylene group which may have a substituent, an arylene group which may have a substituent, and a divalent group formed by bonding two or more of these groups, R ₈ represents a hydrogen atom or An alkyl group having 1 to 18 carbon atoms, and n represents a number of 30 or more.

A substituted or unsubstituted alkyl group represented by R ₁ and R ₂ in the general formula (2), an alkyl group having 1 to 50 carbon atoms represented by R ₇ in the general formula (4), and R ₈ Examples of the alkyl group having 1 to 18 carbon atoms include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, isobutyl, amyl, isoamyl, tert-amyl, hexyl, heptyl, isoheptyl, sec Triheptyl, n-octyl, isooctyl, tertiary octyl, 2-ethylhexyl, nonyl, isononyl, decyl, dodecyl (lauryl), tridecyl, tetradecyl (myristyl), pentadecyl, hexadecyl (palmityl), peptadecyl, octadecyl (stearyl) Can be mentioned.
Examples of the substituted or unsubstituted alkenyl group or alkoxy group represented by R ₁ and R ₂ in the general formula (2) include an alkenyl group or an alkoxy group derived from the alkyl group.
Examples of the substituted or unsubstituted cycloalkyl group represented by R ₁ and R ₂ in the general formula (2) include cyclopentyl, cyclobutyl, cyclohexyl, cycloheptyl and the like.
Examples of the halogen atom represented by R ₁ and R _{2 in} the general formula (2) and X in the general formula (3) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the substituted or unsubstituted acyl group represented by R ₁ and R ₂ in the general formula (2) include acetyl, propionyl, octanoyl, acryloyl, methacryloyl, phenylcarbonyl (benzoyl), phthaloyl, 4-trifluoromethylbenzoyl. , Salicyloyl, oxaloyl, 1,4-butanedicarbonyl, dibutylcarbamoyl, tolylenecarbamoyl, hexamethylenedicarbamoyl and the like.

Examples of the substituted or unsubstituted aromatic group represented by R ₁ and R ₂ in the general formula (2) include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 9-fluorenyl group, a 1-anthryl group, 2-anthryl group, 9-anthryl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group, 1-naphthacenyl group, 2-naphthacenyl group, 9-naphthacenyl group, 1-pyrenyl group, 2-pyrenyl group, 4-pyrenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, p-terphenyl-4-yl group, p-terphenyl-3- Yl group, p-terphenyl-2-yl group, m-terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2-yl group, o-tri Group, m-tolyl group, p-tolyl group, pt-butylphenyl group, p- (2-phenylpropyl) phenyl group, 3-methyl-2-naphthyl group, 4-methyl-1-naphthyl group, 4 An aromatic hydrocarbon group such as -methyl-1-anthryl group, 4'-methylbiphenylyl group, 4 "-t-butyl-p-terphenyl-4-yl group, 1-pyrrolyl group, 2-pyrrolyl group, 3-pyrrolyl group, pyrazinyl group, 2-pyridinyl group, 3-pyridinyl group, 4-pyridinyl group, 1-indolyl group, 2-indolyl group, 3-indolyl group, 4-indolyl group, 5-indolyl group, 6- Indolyl group, 7-indolyl group, 1-isoindolyl group, 2-isoindolyl group, 3-isoindolyl group, 4-isoindolyl group, 5-isoindolyl group, 6-isoindolyl group, 7-isoyl group Drill group, 2-furyl group, 3-furyl group, 2-benzofuranyl group, 3-benzofuranyl group, 4-benzofuranyl group, 5-benzofuranyl group, 6-benzofuranyl group, 7-benzofuranyl group, 1-isobenzofuranyl group 3-isobenzofuranyl group, 4-isobenzofuranyl group, 5-isobenzofuranyl group, 6-isobenzofuranyl group, 7-isobenzofuranyl group, 2-quinolyl group, 3-quinolyl group 4-quinolyl group, 5-quinolyl group, 6-quinolyl group, 7-quinolyl group, 8-quinolyl group, 1-isoquinolyl group, 3-isoquinolyl group, 4-isoquinolyl group, 5-isoquinolyl group, 6-isoquinolyl group 7-isoquinolyl group, 8-isoquinolyl group, 2-quinoxalinyl group, 5-quinoxalinyl group, 6-quinoxalinyl group, 1-carbazolyl group, -Carbazolyl group, 3-carbazolyl group, 4-carbazolyl group, 9-carbazolyl group, 1-phenanthridinyl group, 2-phenanthridinyl group, 3-phenanthridinyl group, 4-phenanthridinyl group 6-phenanthridinyl group, 7-phenanthridinyl group, 8-phenanthridinyl group, 9-phenanthridinyl group, 10-phenanthridinyl group, 1-acridinyl group, 2-acridinyl group , 3-acridinyl group, 4-acridinyl group, 9-acridinyl group, 1,7-phenanthrolin-2-yl group, 1,7-phenanthrolin-3-yl group, 1,7-phenanthrolin- 4-yl group, 1,7-phenanthrolin-5-yl group, 1,7-phenanthrolin-6-yl group, 1,7-phenanthrolin-8-yl group, 1,7-phenance Lorin -9-yl group, 1,7-phenanthrolin-10-yl group, 1,8-phenanthrolin-2-yl group, 1,8-phenanthrolin-3-yl group, 1,8-phen group Nansulolin-4-yl group, 1,8-phenanthrolin-5-yl group, 1,8-phenanthrolin-6-yl group, 1,8-phenanthrolin-7-yl group, 1,8 -Phenanthrolin-9-yl group, 1,8-phenanthrolin-10-yl group, 1,9-phenanthrolin-2-yl group, 1,9-phenanthrolin-3-yl group, 1 , 9-phenanthrolin-4-yl group, 1,9-phenanthrolin-5-yl group, 1,9-phenanthrolin-6-yl group, 1,9-phenanthrolin-7-yl group 1,9-phenanthrolin-8-yl group, 1,9-phenanthrolin-10-yl group, , 10-phenanthrolin-2-yl group, 1,10-phenanthrolin-3-yl group, 1,10-phenanthrolin-4-yl group, 1,10-phenanthrolin-5-yl group 2,9-phenanthrolin-1-yl group, 2,9-phenanthrolin-3-yl group, 2,9-phenanthrolin-4-yl group, 2,9-phenanthrolin-5- Yl group, 2,9-phenanthroline-6-yl group, 2,9-phenanthrolin-7-yl group, 2,9-phenanthrolin-8-yl group, 2,9-phenanthroline- 10-yl group, 2,8-phenanthrolin-1-yl group, 2,8-phenanthrolin-3-yl group, 2,8-phenanthrolin-4-yl group, 2,8-phenance Lorin-5-yl group, 2,8-phenanthrolin-6-yl group, 2,8-fluoro group Nansulolin-7-yl group, 2,8-phenanthroline-9-yl group, 2,8-phenanthrolin-10-yl group, 2,7-phenanthrolin-1-yl group, 2,7- Phenanthrolin-3-yl group, 2,7-phenanthrolin-4-yl group, 2,7-phenanthrolin-5-yl group, 2,7-phenanthrolin-6-yl group, 2, 7-phenanthrolin-8-yl group, 2,7-phenanthrolin-9-yl group, 2,7-phenanthrolin-10-yl group, 1-phenazinyl group, 2-phenazinyl group, 1-pheno Thiazinyl group, 2-phenothiazinyl group, 3-phenothiazinyl group, 4-phenothiazinyl group, 10-phenothiazinyl group, 1-phenoxazinyl group, 2-phenoxazinyl group, 3-phenoxazinyl group, 4-phenoxazinyl group 10-phenoxazinyl group, 2-oxazolyl group, 4-oxazolyl group, 5-oxazolyl group, 2-oxadiazolyl group, 5-oxadiazolyl group, 3-furazanyl group, 2-thienyl group, 3-thienyl group, 2-methylpyrrole -1-yl group, 2-methylpyrrol-3-yl group, 2-methylpyrrol-4-yl group, 2-methylpyrrol-5-yl group, 3-methylpyrrol-1-yl group, 3-methylpyrrole 2-yl group, 3-methylpyrrol-4-yl group, 3-methylpyrrol-5-yl group, 2-t-butylpyrrol-4-yl group, 3- (2-phenylpropyl) pyrrol-1- Yl group, 2-methyl-1-indolyl group, 4-methyl-1-indolyl group, 2-methyl-3-indolyl group, 4-methyl-3-indolyl group, 2-t-butyl-1 Indolyl group, 4-t-butyl-1-indolyl group, 2-t-butyl-3-indolyl group, and 4-t-butyl-3-indolyl group and the like.

Examples of the substituted or unsubstituted aralkyl group represented by R ₁ and R ₂ in the general formula (2) include a benzyl group, a 1-phenylethyl group, a 2-phenylethyl group, a 1-phenylisopropyl group, and 2-phenyl. Isopropyl group, phenyl-t-butyl group, α-naphthylmethyl group, 1-α-naphthylethyl group, 2-α-naphthylethyl group, 1-α-naphthylisopropyl group, 2-α-naphthylisopropyl group, β- Naphthylmethyl group, 1-β-naphthylethyl group, 2-β-naphthylethyl group, 1-β-naphthylisopropyl group, 2-β-naphthylisopropyl group, 1-pyrrolylmethyl group, 2- (1-pyrrolyl) ethyl group P-methylbenzyl group, m-methylbenzyl group, o-methylbenzyl group, p-chlorobenzyl group, m-chlorobenzyl group, o-chlorobenzyl P-bromobenzyl group, m-bromobenzyl group, o-bromobenzyl group, p-iodobenzyl group, m-iodobenzyl group, o-iodobenzyl group, p-hydroxybenzyl group, m-hydroxybenzyl group, o -Hydroxybenzyl group, p-aminobenzyl group, m-aminobenzyl group, o-aminobenzyl group, p-nitrobenzyl group, m-nitrobenzyl group, o-nitrobenzyl group, p-cyanobenzyl group, m-cyano Examples include benzyl group, o-cyanobenzyl group, 1-hydroxy-2-phenylisopropyl group, 1-chloro-2-phenylisopropyl group and the like.

The substituted or unsubstituted alkoxycarbonyl group represented by R ₁ and R ₂ in the general formula (2) is a group represented by —COOX ⁵ , and the substituent X ⁵ is the above-described substituted or unsubstituted group. Examples thereof include an alkyl group, the above substituted or unsubstituted cycloalkyl group, and the above substituted or unsubstituted aralkyl group.

The substituted or unsubstituted amino group represented by R ₁ and R ₂ in the general formula (2) is a group represented by —NX ¹ X ² , and the substituents X ¹ and X ² are each independently hydrogen. Atom, the above substituted or unsubstituted alkyl group, the above substituted or unsubstituted alkenyl group, the above substituted or unsubstituted cycloalkyl group, the above substituted or unsubstituted aromatic group, the above substituted or unsubstituted And an aralkyl group.

The substituted or unsubstituted aryloxy group represented by R ₁ and R ₂ in the general formula (2) is a group represented by —OX ⁴ , and the substituent X ⁴ is the above-described substituted or unsubstituted group. An aromatic group is mentioned.
The substituted or unsubstituted aryloxycarbonyl group represented by R ₁ and R ₂ in the general formula (2) is a group represented by —COOX ⁶ , and the substituent X ⁶ is the above substituted or unsubstituted group. Of the aromatic group.

The alkoxycarbonyl group represented by X in the general formula (3) is a group represented by —COOX ⁵ , and the substituent X ⁵ includes the above substituted or unsubstituted alkyl group and the above substituted or unsubstituted group. And the above-mentioned substituted or unsubstituted aralkyl groups.
Examples of the alkali metal represented by R _{7 in the} general formula (4) and R ₁₀ in the general formula (5) include lithium, sodium, and potassium.

As said C1-C50 aralkyl group represented by R < ₇ > of the said General formula (4), the said substituted or unsubstituted aralkyl group is mentioned.
As the alkyl group substituted with a halogen atom having 1 to 50 carbon atoms represented by R ₇ in the general formula (4), a part or all of the above substituted or unsubstituted alkyl group is substituted with a halogen atom. The thing which was done is mentioned. Specific examples include alkyl fluoride groups, alkyl bromide groups, alkyl iodide groups, alkyl chloride groups, and the like, and the alkyl groups are as described above.

Examples of the alkylene group which may have a substituent represented by X ₁ and X ₂ in the general formula (4) include methylene, ethylene, propylene, methylethylene, butylene, 1-methylpropylene, 2-methylpropylene, 1,2-dimethylpropylene, 1,3-dimethylpropylene, 1-methylbutylene, 2-methylbutylene, 3-methylbutylene, 4-methylbutylene, 2,4-dimethylbutylene, 1,3-dimethylbutylene, pentylene, Hexylene, heptylene, octylene, ethane-1,1-diyl, propane-2,2-diyl, cyclopropane-1,1-diyl, cyclobutane-1,1-diyl, 2,4-dimethylcyclobutane-1,1 -Diyl, 3-dimethylcyclobutane-1,1-diyl, cyclopentane-1,1-diyl, cyclohex Examples of the arylene group that may have a substituent include 1,2-phenylene, 1,3-phenylene, 1,4-phenylene, and 2,5-dimethyl-1. , 4-phenylene, diphenylmethane-4,4′-diyl, 2,2-diphenylpropane-4,4′-diyl, diphenyl sulfide-4,4′-diyl, diphenylsulfone-4,4′-diyl and the like. It is done.

  As a preferable nitroxy radical compound represented by the above general formula (1), general formula (2), general formula (3), general formula (4) or general formula (5), more specifically, Compound No. 1-No. 9 is mentioned. However, this invention is not restrict | limited at all by the following illustrations.

  Of the radical materials used in the present invention, a nitroalkyl radical compound is particularly preferably used. More preferably, the radical compound is represented by the above general formula (3), general formula (4) or general formula (5). Nitroalkyl radical compound.

  The conductive material-containing radical material used in the present invention can be obtained by synthesizing a radical material by a method such as anionic polymerization in the liquid phase and immediately after that, by mixing the conductive material in the liquid phase. Examples of the conductive material include a carbon material or a conductive polymer. Examples of the carbon material include carbon black such as acetylene black, ketjen black, and fine particles of graphite, and fine particles of amorphous carbon such as needle coke. Examples thereof include carbonaceous materials such as nanofibers, graphite, carbon nanotubes, and amorphous carbon. Examples of the conductive polymer include polyaniline, polypyrrole, polythiophene, polyacetylene, polyacene and the like. Among these, carbon materials are particularly preferable, and acetylene black and ketjen black are particularly preferably used.

  The amount of the conductive material mixed is preferably 5 to 80% by mass, more preferably 25 to 40% by mass in the conductive material-containing radical material.

  Examples of the method for mixing the radical material and the conductive material include a method in which a conductive material is added to and mixed with a radical material dissolved in a polymerization solvent such as toluene or xylene immediately after anionic polymerization. In the case of a method in which the radical material is isolated and then mixed with the conductive material, it is difficult to mix with the conductive material because the isolated radical material is insoluble in the solvent, and even when heated and forcibly mixed. It finally gels and is difficult to remove as a uniform mixture.

Next, the secondary battery of the present invention will be described.
The secondary battery of the present invention is a secondary battery having at least a positive electrode, a negative electrode, and an electrolytic solution as constituent elements, wherein the positive electrode is the above-described secondary battery electrode of the present invention.
As the positive electrode active material, not only the conductive material-containing radical material can be used alone, but also a compound that inserts and desorbs lithium ions can be mixed and used. The proportion of the conductive material-containing radical material in the positive electrode active material is preferably in the range of 2 to 100% by mass, more preferably 3 to 75% by mass, and still more preferably 5 to 50% by mass. Examples of the compound that inserts and desorbs lithium ions include a lithium-metal composite oxide having a layered structure or a spinel structure. Specifically, Li _(1-X) NiO ₂ , Li _(1-X) MnO ₂ Li _(1-X) Mn ₂ O ₄ , Li _(1-X) CoO ₂ , Li _(1-X) FeO ₂ , LiFePO _{4 and the} like. X in these chemical formulas represents a number from 0 to 1. A material obtained by adding or substituting a transition metal such as Li, Mg, Al, or Co, Ti, Nb, or Cr may be used. Moreover, not only these lithium-metal composite oxides are used alone, but also a plurality of these can be mixed and used. Among these, the lithium-metal composite oxide is preferably at least one of a lithium manganese-containing composite oxide having a layered structure or a spinel structure, a lithium nickel-containing composite oxide, and a lithium cobalt-containing composite oxide. The positive electrode is preferably one in which the positive electrode active material is mixed with a known additive such as a binder or a conductive material and then applied onto a current collector made of a metal foil or the like to form a positive electrode mixture layer. . Examples of the binder include polyvinylidene fluoride, polytetrafluoroethylene, EPDM, SBR, NBR, and fluororubber.

The active material of the negative electrode is not particularly limited as long as it is a compound that occludes lithium ions during charge and releases during discharge, and any known material or configuration can be used. . Examples thereof include lithium metal, carbon materials such as graphite or amorphous carbon, alloy materials containing silicon, tin, and the like, and oxide materials such as Li ₄ Ti ₅ O ₁₂ and Nb ₂ O ₅ . The above oxide materials may be used in a mixture of a plurality of types in addition to being used alone. The negative electrode is preferably one in which a negative electrode mixture obtained by mixing the negative electrode active material with a conductive material and a binder as necessary is bonded to a current collector to form a negative electrode mixture layer.

  Usually, copper, nickel, stainless steel, nickel-plated steel or the like is used as the negative electrode current collector, and aluminum, stainless steel, nickel-plated steel or the like is usually used as the positive electrode current collector. .

  The electrolytic solution is prepared by dissolving a supporting salt in an organic solvent, an ionic liquid, or a supporting salt dissolved in an ionic liquid.

  As said organic solvent, what is normally used for the non-aqueous electrolyte can be used 1 type or in combination of 2 or more types, but a cyclic carbonate compound, a cyclic ester compound, a sulfone or sulfoxide compound, an amide compound, a chain form It is preferable to contain at least one selected from the group consisting of a carbonate compound, a chain or cyclic ether compound, and a chain ester compound. In particular, it is preferable to contain at least one cyclic carbonate compound and a chain carbonate compound, and by using this combination, not only the cycle characteristics are excellent, but also the viscosity of the electrolyte, the electric capacity / output of the obtained battery, etc. A non-aqueous electrolyte with a good balance can be provided.

  Among the organic solvents, a cyclic carbonate compound, a cyclic ester compound, a sulfone or sulfoxide compound, and an amide compound have a high relative dielectric constant, and thus serve to increase the dielectric constant of the electrolytic solution.

  Specifically, examples of the cyclic carbonate compound include ethylene carbonate (EC), propylene carbonate (PC), vinylene carbonate (VC), 1,2-butylene carbonate, and isobutylene carbonate. Examples of the cyclic ester compound include γ-butyrolactone and γ-valerolactone. Examples of the sulfone or sulfoxide compound include sulfolane, sulfolene, tetramethylsulfolane, diphenyl sulfone, dimethyl sulfone, dimethyl sulfoxide, and the like. Among these, sulfolanes are preferable. Examples of the amide compound include N-methylpyrrolidone, dimethylformamide, dimethylacetamide and the like.

  The chain carbonate compound, the chain or cyclic ether compound, and the chain ester compound can lower the viscosity of the non-aqueous electrolyte. Therefore, battery characteristics such as power density can be improved, such as the mobility of electrolyte ions can be increased. Moreover, since it is low-viscosity, the performance of the non-aqueous electrolyte at low temperatures can be increased.

  Specifically, as the chain carbonate compound, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), ethyl-n-butyl carbonate, methyl-t-butyl carbonate, di-i-propyl Examples thereof include carbonate and t-butyl-i-propyl carbonate. Examples of the chain or cyclic ether compound include dimethoxyethane (DME), ethoxymethoxyethane, diethoxyethane, tetrahydrofuran, dioxolane, dioxane, 1,2-bis (methoxycarbonyloxy) ethane, 1,2-bis (ethoxycarbonyloxy). ) Ethane, 1,2-bis (ethoxycarbonyloxy) propane, ethylene glycol bis (trifluoroethyl) ether, i-propylene glycol (trifluoroethyl) ether, ethylene glycol bis (trifluoromethyl) ether, diethylene glycol bis (tri Fluoroethyl) ether and the like. Among these, dioxolanes are preferable. Examples of the chain ester compound include a carboxylic acid ester compound represented by the following general formula (6).

（式中、Ｒは炭素原子数１〜４のアルキル基を示す。ｎは０、１又は２を示す。）

(In the formula, R represents an alkyl group having 1 to 4 carbon atoms. N represents 0, 1 or 2.)

  Examples of the alkyl group having 1 to 4 carbon atoms in the general formula (6) include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl and tert-butyl. Specifically, methyl formate, ethyl formate, Examples include methyl acetate, ethyl acetate, propyl acetate, sec-butyl acetate, butyl acetate, methyl propionate, and ethyl propionate. In addition, acetonitrile, propionitrile, nitromethane, and derivatives thereof can also be used.

Further, the ionic liquid is not particularly limited as long as it is an ionic liquid usually used for an electrolyte of a lithium secondary battery. For example, as a cation component, 1-methyl-3-ethylimidazolium having high conductivity is used. Examples of the anion component include BF ₄ ⁻ , LiN (SO ₂ C ₂ F ₅ ) ₂ ^{— and the} like.

The kind of the supporting salt (electrolyte salt) is not particularly limited, but an inorganic salt selected from LiPF ₆ , LiBF ₄ , LiClO ₄ and LiAsF ₆ , a derivative of the inorganic salt, LiSO ₃ CF ₃ , LiC ( Organic salts selected from SO ₂ CF ₃ ) ₂ , LiN (SO ₂ CF ₃ ) ₂ , LiN (SO ₂ C ₂ F ₅ ) _2, LiN (SO ₂ CF ₃ ) (SO ₂ C ₄ F ₉ ), etc., and The organic salt is preferably at least one of its derivatives. There is no particular limitation on the concentration of the supporting salt, and it is preferable to select appropriately in consideration of the types of the supporting salt and the solvent according to the use. The supporting salt is preferably dissolved in the organic solvent so that the concentration in the electrolytic solution is 0.1 to 3.0 mol / liter, particularly 0.5 to 2.0 mol / liter. If the concentration of the supporting salt is less than 0.1 mol / liter, a sufficient current density may not be obtained. If the concentration is greater than 3.0 mol / liter, the stability of the non-aqueous electrolyte may be impaired. .

  The secondary battery of the present invention usually has a separator. The separator plays a role of electrically insulating the positive electrode and the negative electrode and holding the electrolytic solution. As the separator, for example, a porous synthetic resin film, particularly a porous film of a polyolefin polymer (polyethylene, polypropylene) may be used. Note that the separator is preferably larger than the positive electrode and the negative electrode in order to ensure insulation between the positive electrode and the negative electrode.

  As the separator, a commonly used polymer microporous film can be used without particular limitation. Examples of the film include polyethylene, polypropylene, polyvinylidene fluoride, polyvinylidene chloride, polyacrylonitrile, polyacrylamide, polytetrafluoroethylene, polysulfone, polyethersulfone, polycarbonate, polyamide, polyimide, polyethylene oxide and polypropylene oxide. Films composed of ethers, various celluloses such as carboxymethylcellulose and hydroxypropylcellulose, polymer compounds mainly composed of poly (meth) acrylic acid and various esters thereof, derivatives thereof, copolymers and mixtures thereof. Etc. These films may be used alone or may be used as a multilayer film by superimposing these films. Furthermore, various additives may be used for these films, and the type and content thereof are not particularly limited. Among these films, films made of polyethylene, polypropylene, polyvinylidene fluoride, and polysulfone are preferably used.

  These films are microporous so that the electrolyte can penetrate and ions can easily pass therethrough. The microporosity method includes a phase separation method in which a polymer compound and a solvent solution are formed into a film while microphase separation is performed, and the solvent is extracted and removed to make it porous. The film is extruded and then heat-treated, the crystals are aligned in one direction, and a gap is formed between the crystals by stretching to make it porous, and so on.

  The conductive material-containing radical material according to the present invention includes hindered amine light stabilizers (HALS), ultraviolet absorbers, phosphorus-based, phenol-based, sulfur-based antioxidants, nucleating agents, Flame retardants, metal soaps, processing aids, fillers, dispersants, emulsifiers, lubricants, colored dyes, colored pigments, antistatic agents, antiseptics, antibacterial agents, antifungal agents, plasticizers, antifoaming agents, viscosity modifiers Commonly used additives such as leveling agents, surfactants, fluorescent brighteners, pH adjusters, thickeners, anti-aggregation agents, and fragrances can be used in combination.

  The shape of the secondary battery of the present invention is not particularly limited, and can be various shapes such as a coin shape, a cylindrical shape, and a square shape. FIG. 1 shows an example of a coin type battery of the secondary battery of the present invention, and FIGS. 2 and 3 show an example of a cylindrical battery of the secondary battery of the present invention.

  In the coin-type secondary battery 10 shown in FIG. 1, 1 is a positive electrode capable of releasing lithium ions, 1a is a positive electrode current collector, 2 is a negative electrode made of a carbonaceous material capable of inserting and extracting lithium ions released from the positive electrode, 2a is a negative electrode current collector, 3 is an electrolytic solution, 4 is a stainless steel positive electrode case, 5 is a stainless steel negative electrode case, 6 is a polypropylene gasket, and 7 is a polyethylene separator.

  2 and 3, 11 is a negative electrode, 12 is a negative electrode current collector, 13 is a positive electrode, 14 is a positive electrode current collector, 15 is an electrolytic solution, 16 is a separator, 17 is a positive electrode terminal, 18 is a negative electrode terminal, 19 is a negative electrode plate, 20 is a negative electrode lead, 21 is a positive electrode plate, 22 is a positive electrode lead, 23 is a case, 24 is an insulating plate, 25 is a gasket, 26 is a safety valve, and 27 is a PTC. It is an element.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not restrict | limited by a following example.

[Example 1]
Under a nitrogen atmosphere, a 2-liter 4-necked flask equipped with a stirrer was charged with 135 g (0.563 mol) of 4-methacryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 6.75 g of ethylene glycol dimethacrylate ( 0.034 mol), 1.35 g (0.008 mol) of n-hexyl methacrylate and 780 ml of dry toluene were charged and cooled to −10 ° C. 14.0 ml (0.028 mol) of a 2M ether solution of cyclopentylmagnesium chloride was slowly added dropwise so that the internal temperature did not exceed -5 ° C. The mixture was stirred as it was at −10 ° C. for 5 hours, and further stirred at room temperature for 5 hours. 34 g of acetic acid and 34 g of methanol were added to the reaction solution to deactivate the catalyst, and then 12.7 g of ketjen black was added and stirred until a uniform slurry was obtained. The slurry was added dropwise to 10 liters of a mixed solvent of water / methanol (1/9) while stirring, followed by stirring for 30 minutes, followed by filtration and drying to obtain a dark gray powder (radical material from compound No. 1). Thus, 127 g of a conductive material-containing radical material was obtained. The yield of the piperidyl group-containing high molecular weight polymer was 80%. In addition, content of the electrically conductive material of the obtained electrically conductive material containing radical material is 10 mass%.

(Preparation of positive electrode)
80 parts by mass of LiNi _0.82 Co _0.15 Al _0.03 O ₂ , 5.56 parts by mass of the conductive material-containing radical material (5 parts by mass of the radical material of compound No. 1, 0.56 parts by mass of the conductive material), and acetylene black 12 parts by mass, 1 part by mass of carboxymethylcellulose sodium salt (CMC) and 1 part by mass of polyethylene oxide (PEO) are dispersed in 80 parts by mass of water, and polytetrafluoroethylene (PTFE) as a binder. ) Was added and dispersed to obtain a slurry. This slurry was applied to both sides of a positive electrode current collector made of aluminum, dried and press-molded to obtain a positive electrode plate. Then, this positive electrode plate was cut into a predetermined size, and a sheet-like positive electrode was produced by scraping off the electrode mixture at a portion that became a lead tab weld for extracting current.

(Preparation of negative electrode)
98 parts by mass of carbon material powder as a negative electrode active material, 1 part by mass of sodium carboxymethylcellulose (CMC) are dispersed in 98 parts by mass of water, and 1 mass of styrene butadiene rubber (SBR) is further used as a binder. Part was added and dispersed to form a slurry. This slurry was applied to both sides of a copper negative electrode current collector, dried and press-molded to obtain a negative electrode plate. Then, this negative electrode plate was cut into a predetermined size, and a sheet-like negative electrode was produced by scraping off the electrode composite material at a portion to be a lead tab weld for extracting current.

(Preparation of electrolyte)
Ethylene carbonate (EC) and diethyl carbonate (DEC) were mixed at a volume ratio of 3: 7, and LiPF ₆ was dissolved in the mixed organic solvent at a concentration of 1 mol / liter to obtain an electrolytic solution.

(Battery assembly)
The sheet-like positive electrode and the sheet-like negative electrode obtained above were wound with a 25 μm-thick microporous polyethylene film as a separator interposed therebetween to form a wound electrode body. The obtained wound electrode body was inserted into the case and held in the case. At this time, one end of the current collecting lead was welded to the lead tab weld portion of the sheet-like positive electrode and the sheet-like negative electrode, and the other end of the current collecting lead was joined to the positive electrode terminal and the negative electrode terminal of the case. Then, after inject | pouring the said electrolyte solution in the case holding the winding type electrode body, the case was sealed and sealed.
Through the above procedure, a cylindrical secondary battery having a diameter of 18 mm and an axial length of 65 mm was manufactured and used as a test battery of this example.

(Initial charge / discharge)
The initial charge / discharge of the produced secondary battery was performed under the following conditions. First, the battery was charged at a constant current of 3.9 V at a charging current of 0.25 mA / cm ² (current value corresponding to 1/4 C, 1 C is a current value that discharges the battery capacity in one hour), and the discharging current was 0.33 mA / cm ^2. A constant current discharge was performed up to 3.0 V (current value corresponding to 1/3 C). Next, the battery was charged at a constant current and a constant current (current value corresponding to 1C) to 4.1V with a charging current 1.1mA / cm ² (current value corresponding to 1C), and discharged current 1.1mA / cm ² (current corresponding to 1C). Value) at a constant current of 3.0V. Similarly, five cycles of charge / discharge were performed to obtain initial charge / discharge. Moreover, this initial charge / discharge was performed in an atmosphere at 20 ° C.

(Low temperature characteristic evaluation test method)
After the initial discharge, the temperature was kept at 20 ° C., and the battery was CC-CV charged to 3.618 V (SOC 40%) at a charging current of 1000 mA. Thereafter, in a constant temperature bath of −30 ° C., discharging 2 points for 10 seconds in order of 100 mA, 200 mA, 300 mA, 400 mA, 600 mA and 1000 mA, respectively, charging for 10 seconds is repeated, and the current value and the closed circuit battery voltage at each point are calculated. The current value at the point where the straight line connecting the two points around 3.0V intersected 3.0V was read, and the output was obtained by multiplying the current value by 3V. The output value was determined by converting the output at the positive electrode (Comparative Example 1) in which the positive electrode active material is composed solely of LiNiO ₂ to 100. The results are shown in Table 1.

[Example 2]
As a conductive material-containing radical material, Compound No. Except that 6.67 parts by mass of a conductive material-containing radical material consisting of 5 parts by mass of 1 radical material and 1.67 parts by mass of ketjen black (the content of the conductive material of the conductive material-containing radical material is 25% by mass) In the same manner as in Example 1, a secondary battery was produced and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

Example 3
As a conductive material-containing radical material, Compound No. Except for using 7.5 parts by mass of a conductive material-containing radical material consisting of 5 parts by mass of 1 radical material and 2.5 parts by mass of Ketjen Black (the content of the conductive material of the conductive material-containing radical material is 33% by mass) In the same manner as in Example 1, a secondary battery was produced and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

Example 4
As a conductive material-containing radical material, Compound No. Except for using 8.33 parts by mass of a conductive material-containing radical material consisting of 5 parts by mass of 1 radical material and 3.33 parts by mass of ketjen black (the conductive material content of the conductive material-containing radical material is 40% by mass). In the same manner as in Example 1, a secondary battery was produced and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

Example 5
As a conductive material-containing radical material, Compound No. Example 1 except that 10 parts by mass of a conductive material-containing radical material consisting of 5 parts by mass of the radical material 1 and 5 parts by mass of ketjen black (the content of the conductive material of the conductive material-containing radical material is 50% by mass) is used. In the same manner as described above, a secondary battery was manufactured and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

Example 6
As a conductive material-containing radical material, Compound No. Except for using 2.67 parts by mass of a conductive material-containing radical material consisting of 2 parts by mass of 1 radical material and 0.67 parts by mass of ketjen black (the conductive material content of the conductive material-containing radical material is 25% by mass) In the same manner as in Example 1, a secondary battery was produced and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

Example 7
As a conductive material-containing radical material, Compound No. Except for using 5.32 parts by mass of a conductive material-containing radical material consisting of 4 parts by mass of 1 radical material and 1.32 parts by mass of ketjen black (the conductive material content of the conductive material-containing radical material is 25% by mass) In the same manner as in Example 1, a secondary battery was produced and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

Example 8
As a conductive material-containing radical material, Compound No. Example 1 except that 30 parts by mass of a conductive material-containing radical material consisting of 20 parts by mass of the radical material 1 and 10 parts by mass of ketjen black (the content of the conductive material of the conductive material-containing radical material is 33% by mass) is used. In the same manner as described above, a secondary battery was manufactured and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

Example 9
As a conductive material-containing radical material, Compound No. Example 1 except that 30 parts by mass of a conductive material-containing radical material consisting of 20 parts by mass of a radical material 1 and 10 parts by mass of carbon fiber (the content of the conductive material of the conductive material-containing radical material is 33% by mass) is used. Similarly, a secondary battery was produced and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

Example 10
163 g of 4-amino-2,2,6,6-tetramethylpiperidine was slowly dropped into a 2-liter 5-neck flask charged with 154 g of a polyisobutylene maleic anhydride alternating copolymer having a weight average molecular weight of 80,000 and 1440 g of dimethylacetamide. Then, the temperature was raised to 150 ° C. in an oil bath. After 12 hours, the temperature was returned to room temperature and dropped into 36 liters of acetone while stirring to precipitate a polymer. By filtration and vacuum drying, 298 g of an imide polymer was obtained. The yield of imide polymer was 96%. This 298 g of polymer was mixed with a mixed solvent of 1150 g of ethanol and 580 g of ion-exchanged water in a 5-liter 5-neck flask and dissolved at 60 ° C. 0.6 g of silicotungstic acid was added thereto, and 272 g of 30% aqueous hydrogen peroxide was slowly dropped while maintaining the temperature at 60 ° C. After the dropping, the reaction was maintained at 75 ° C. for 10 hours to complete the oxidation reaction. After returning to room temperature, 140 g of ketjen black was added and mixed for 30 minutes to obtain a uniform slurry. The slurry was dropped into 20 liters of water while stirring to precipitate a polymer. Stirring was continued for 30 minutes, followed by filtration and drying to obtain 416 g of a dark gray powder (a conductive material-containing radical material in which the radical material is compound No. 2). Compound No. The yield of the high molecular weight polymer of 2 was 88%. In addition, content of the electrically conductive material of the obtained electrically conductive material containing radical material is 33 mass%.
In the same manner as in Example 1, except that 30 parts by mass of the conductive material-containing radical material (20 parts by mass of the radical material of Compound No. 2 and 10 parts by mass of Ketjen Black) were used as the conductive material-containing radical material. A secondary battery was fabricated and subjected to a low temperature characteristic evaluation test. The results are shown in Table 1.

Example 11
40 parts by mass of LiNi _0.82 Co _0.15 Al _0.03 O ₂ and 60 parts by mass of the conductive material-containing radical material obtained in Example 1 (40 parts by mass of the radical material of Compound No. 1 and 20 parts by mass of Ketjen Black) , 12 parts by mass of acetylene black, 2 parts by mass of sodium carboxymethylcellulose (CMC) and 2 parts by mass of polyethylene oxide (PEO) are dispersed in 100 parts by mass of water, and polytetrafluoro as a binder. A secondary battery was produced in the same manner as in Example 1 except that 2 parts by mass of ethylene (PTFE) was added and dispersed to form a slurry, and a positive electrode was produced using this slurry. . The results are shown in Table 1.

Example 12
120 parts by mass of the conductive material-containing radical material obtained in Example 1 (80 parts by mass of the radical material of Compound No. 1 and 40 parts by mass of ketjen black), 2 parts by mass of carboxymethylcellulose sodium salt (CMC), 2 parts by mass of polyethylene oxide (PEO) is dispersed in 80 parts by mass of water, and 2 parts by mass of polytetrafluoroethylene (PTFE) is further added and dispersed as a binder to form a slurry. A secondary battery was produced in the same manner as in Example 1 except that the low-temperature characteristic evaluation test was performed. The results are shown in Table 1.

Example 13
Compound No. 200 parts by mass of a conductive material-containing radical material composed of 80 parts by mass of 1 radical material and 120 parts by mass of ketjen black (the content of the conductive material of the conductive material-containing radical material is 60% by mass) and carboxymethylcellulose sodium salt (CMC 2 parts by mass) and 2 parts by mass of polyethylene oxide (PEO) are dispersed in 80 parts by mass of water, and 2 parts by mass of polytetrafluoroethylene (PTFE) is further added and dispersed as a binder to form a slurry. A secondary battery was produced in the same manner as in Example 1 except that a positive electrode was produced using this slurry, and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

[Comparative Example 1]
A positive electrode was produced in the same manner as in Example 1 except that only 80 parts by mass of LiNi _0.82 Co _0.15 Al _0.03 O ₂ was used as the positive electrode active material. A secondary battery was fabricated and subjected to a low temperature characteristic evaluation test. The results are shown in Table 1.

[Comparative Example 2]
Under a nitrogen atmosphere, a 2-liter 4-necked flask equipped with a stirrer was charged with 135 g (0.563 mol) of 4-methacryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 6.75 g of ethylene glycol dimethacrylate ( 0.034 mol), 1.35 g (0.008 mol) of n-hexyl methacrylate and 780 ml of dry toluene were charged and cooled to −10 ° C. 14.0 ml (0.028 mol) of a 2M ether solution of cyclopentylmagnesium chloride was slowly added dropwise so that the internal temperature did not exceed -5 ° C. The mixture was stirred as it was at −10 ° C. for 5 hours, and further stirred at room temperature for 5 hours. After adding 34 g of acetic acid and 34 g of methanol to the reaction solution to deactivate the catalyst, this slurry was added dropwise with stirring to 10 liters of a mixed solvent of water / methanol (1/9), and stirring was continued for 30 minutes, followed by filtration. Then, 113 g of orange powder (Compound No. 1 radical material) was obtained by drying. The yield of the piperidyl group-containing high molecular weight polymer was 79%.
A positive electrode was produced in the same manner as in Example 1 except that 80 parts by mass of LiNi _{0.8 2} Co _0.15 Al _0.03 O ₂ and 5 parts by mass of the radical material were used as the positive electrode active material. In the same manner as in Example 1, a secondary battery was produced and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

[Comparative Example 3]
A positive electrode was produced in the same manner as in Example 1 except that 80 parts by mass of LiNi _0.82 Co _0.15 Al _0.03 O ₂ and 5 parts by mass of ketjen black were used as the positive electrode active material, and this positive electrode was used. In the same manner as in Example 1, a secondary battery was produced and a low temperature characteristic evaluation test was performed. The results are shown in Table 1.

[Comparative Example 4]
As a positive electrode active material, Compound No. A positive electrode was produced in the same manner as in Example 1 except that 80 parts by mass of only one radical material and 40 parts by mass of acetylene black were used, and the same procedure as in Example 1 was conducted except that this positive electrode was used. A secondary battery was fabricated and subjected to a low temperature characteristic evaluation test. The results are shown in Table 1.

As is clear from the above [Table 1], in the secondary battery of the example containing the conductive material-containing radical material mixed and synthesized in the radical material synthesis stage in the positive electrode, the low temperature output is greatly improved. is doing. In the secondary battery of Comparative Example 2 added with the radical material alone, the output is slightly improved as compared with Comparative Example 1 without the radical material, but the radical material itself has almost no conductivity so that a sufficient conductive path is ensured. It is not possible to extract the original performance of the radical material. Therefore, output improvement is slight compared with the comparative example 1 without a radical material.
In addition, in the secondary batteries of Examples 12 to 13 containing only the conductive material-containing radical material as the positive electrode active material, the binder material was added twice the usual amount in order to maintain the adhesion to the current collector. It was confirmed that a high low-temperature output could be obtained. Furthermore, in the secondary battery of the example, it was confirmed that a larger output was obtained than the secondary battery of Comparative Example 4 in which the radical material and the conductive material were simply mixed when the positive electrode slurry was produced, and the energy density could be improved.

FIG. 1 is a longitudinal sectional view schematically showing an example of the structure of a coin-type battery of the nonaqueous electrolyte secondary battery of the present invention. FIG. 2 is a schematic diagram showing a basic configuration of a cylindrical battery of the nonaqueous electrolyte secondary battery of the present invention. FIG. 3 is a perspective view showing the internal structure of the cylindrical battery of the nonaqueous electrolyte secondary battery of the present invention as a cross section.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Positive electrode 1a Positive electrode collector 2 Negative electrode 2a Negative electrode collector 3 Electrolyte solution 4 Positive electrode case 5 Negative electrode case 6 Gasket 7 Separator 10 Coin type nonaqueous electrolyte secondary battery 10 Cylindrical type nonaqueous electrolyte secondary battery 11 Negative electrode 12 Negative electrode current collector 13 Positive electrode 14 Positive electrode current collector 15 Electrolyte 16 Separator 17 Positive electrode terminal 18 Negative electrode terminal 19 Negative electrode plate 20 Negative electrode lead 21 Positive electrode plate 22 Positive electrode lead 23 Case 24 Insulating plate 25 Gasket 26 Safety valve 27 PTC element

Claims (5)

After the radical material is synthesized by a polymerization reaction in a liquid phase, a conductive material-containing radical material obtained by mixing a conductive material in the liquid phase is contained in an electrode, and the radical material is represented by the following general formula (4) or the following general formula: A method for producing an electrode for a secondary battery, which is a nitroxyl radical compound which is a piperidyl group-containing high molecular weight polymer or copolymer having a structure represented by the formula (5).

(In the formula, R ₄ represents a hydrogen atom, a methyl group or —COOLi, R ₅ and R ₆ each independently represent a hydrogen atom or a methyl group, and R ₇ represents a hydrogen atom, an alkali metal, or a carbon atom. the number 1 to 50 alkyl group, an alkenyl group having a carbon number of 1 to 50, an aralkyl group having 1 to 50 carbon atom, an alkyl group substituted with a halogen atom having 1 to 50 carbon atom .X ₁ and X ₂ may each independently have a direct bond, —CO—, —COO—, —CONR ₈ —, —O—, —S—, an alkylene group which may have a substituent, or a substituent. An arylene group or a divalent group formed by bonding two or more of these groups, R ₈ represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, n represents a number of 30 or more, m Represents 0 or a positive number.)

(In the formula, R ₉ represents a hydrogen atom or a methyl group, and R ₁₀ represents a hydrogen atom, an alkali metal, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 1 to 30 carbon atoms, or 1 carbon atom. An arylalkyl group having ˜30, or an alkyl group substituted with a halogen atom having 1 to 30 carbon atoms, X ₂ is a direct bond, —CO—, —COO—, —CONR ₈ —, —O—, — S— represents an alkylene group which may have a substituent, an arylene group which may have a substituent, or a divalent group formed by bonding two or more of these groups, R ₈ represents a hydrogen atom Or an alkyl group having 1 to 18 carbon atoms, and n represents a number of 30 or more.)   The method for producing an electrode for a secondary battery according to claim 1, wherein the amount of the conductive material mixed is 5 to 80% by mass in the conductive material-containing radical material.   The secondary content according to claim 1 or 2, wherein the content of the conductive material-containing radical material is 2 to 100% by mass in the total amount of the conductive material-containing radical material and the other active material. Manufacturing method of battery electrode.   The method for producing an electrode for a secondary battery according to claim 1, wherein the conductive material is selected from carbon materials. The method for producing an electrode for a secondary battery according to claim 4, wherein the carbon material is carbon black .

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