JP6248947B2 - Electrode material and secondary battery - Google Patents

Description

  The present invention relates to a secondary battery using a radical compound as an electrode active material.

  In recent years, with the development of communication systems, portable electronic devices such as notebook computers, mobile phones, and smartphones have rapidly spread. While mobile electronic devices are becoming more sophisticated, functions and shapes are also diversifying. Therefore, various demands such as a high energy density, a high output density, a small size, and a light weight are increasing for the secondary battery as the power source.

  Therefore, secondary batteries using sulfur compounds or organic compounds as electrode active materials have been developed for the purpose of obtaining lightweight secondary batteries with high energy density. Patent Document 1 and Patent Document 2 disclose secondary batteries using an organic compound having a disulfide bond as a positive electrode. These secondary batteries utilize an electrochemical redox reaction involving generation and dissociation of disulfide bonds. The secondary batteries described in Patent Documents 1 and 2 are made of an electrode material mainly composed of an element having a small specific gravity such as sulfur or carbon, and have a certain effect in terms of a secondary battery having a high energy density. ing.

  However, in the secondary batteries of Patent Documents 1 and 2, it is possible to perform a stable charge / discharge cycle because the dissociated disulfide bond is low in the efficiency of binding again and the active material in the electrode diffuses into the electrolyte. There were cases where it was not possible. Therefore, depending on the case, there is a drawback that the capacity tends to decrease when the charge and discharge cycles are repeated.

  As secondary batteries using organic compounds, secondary batteries using conductive polymers as electrode materials have been proposed. This secondary battery utilizes electrolyte ion doping and dedoping reactions with respect to a conductive polymer. The dope reaction is a reaction in which a charged radical generated by oxidation or reduction of a conductive polymer is stabilized by a counter ion. Patent Document 3 discloses a secondary battery using such a conductive polymer as a positive electrode or negative electrode material.

  In the secondary battery of Patent Document 3, the electrode material is composed only of an element having a small specific gravity such as carbon or nitrogen, and is expected as a high-capacity secondary battery. However, conductive polymers have the property that charged radicals generated by redox are delocalized over a wide range of π-electron conjugated systems and interact with each other, resulting in electrostatic repulsion and radical disappearance. is there. This brings a limit to the generated charged radicals, that is, the dope concentration, and limits the capacity of the secondary battery. For example, it has been reported that the doping rate of a secondary battery using polyaniline as a positive electrode is 50% or less, and 7% in the case of polyacetylene. Although a secondary battery using a conductive polymer as an electrode material has a certain effect in terms of weight reduction, a secondary battery having a large energy density has not been obtained.

  On the other hand, as a secondary battery using an organic compound as an active material for an electrode, a battery using a redox reaction of a radical compound has been proposed. This secondary battery is called an organic radical battery. Patent Document 4 discloses an organic radical compound such as a nitroxyl radical compound, an aryloxy radical compound, and a polymer having a specific aminotriazine structure as an active material for an electrode, and uses the organic radical compound as a material for a positive electrode or a negative electrode. A secondary battery is disclosed.

  Patent Document 5 discloses a secondary battery using a compound having a cyclic nitroxyl structure as an electrode active material among nitroxyl compounds. Cyclic nitroxyl structures are known to exhibit stable p-type redox. The polyradical compound used as an active material for electrodes includes poly (2,2,6,6-tetramethylpiperidine-1- having 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO). Nitroxyl radical compounds such as oxyl methacrylate (PTMA) are known. In the oxidation-reduction reaction of a nitroxyl radical compound, an oxoammonium cation partial structure is taken in the oxidation state, a nitroxyl radical partial structure is taken in the reduction state, and electrons are transferred between the two states. Since this electrode reaction proceeds relatively quickly, a secondary battery using a nitroxyl radical compound as an electrode can be discharged with a large current.

  Patent Document 6 discloses an organic radical battery using a composite of a nitroxyl compound and a conductive material as an electrode. For example, when carbon is used for the conductive material, the dispersibility of carbon in the electrode is improved. For this reason, electrode resistance is reduced. Thereby, a secondary battery with higher output is obtained.

US Pat. No. 4,833,048 Japanese Patent No. 2715778 U.S. Pat. No. 4,442,187 JP 2002-151084 A JP 2002-304996 A JP 2009-230951 A

  An organic radical battery is a battery capable of discharging with a large current, that is, a battery capable of high output discharge. However, the battery has a lower energy density than the Li ion battery. The energy density of a Li-ion battery for portable electronic devices is said to be 500 Wh / L or more per volume, but in the case of an organic radical battery, it is 100 Wh / L or less, which is smaller than that of a Li-ion battery. This is because the capacity density as an electrode active material of an organic radical battery is smaller than that of a Li ion battery, and the amount of electrolyte required in theory is considerably larger in an organic radical battery than in a Li ion battery. To do.

The capacity density of the electrode active material of the organic radical battery is 111 mAh / g per weight in poly (2,2,6,6-tetramethylpiperidine-1-oxyl methacrylate) (PTMA) which is a typical electrode active material. . On the other hand, the theoretical capacity density of LiCoO ₂ , which is a typical electrode active material for Li-ion batteries, is 140 mAh / g, which is larger than the electrode active material for organic radical batteries. In organic radical batteries, electrode active materials having a smaller capacity density than Li-ion batteries are mainly used. This contributes to a lower energy density than Li-ion batteries.

  In an organic radical battery using PTMA, the form of redox is p-type redox performed between a neutral radical and a cation. In this case, since the anion of the electrolyte salt is doped into the radical compound as the charging proceeds, the anion concentration in the electrolytic solution decreases. Conversely, during discharge, the anion concentration in the electrolyte increases due to dedoping from the radical compound. For this reason, in the case of p-type redox, it is necessary to store an anion serving as a dopant in the electrolytic solution, and a large amount of electrolytic solution is required. As a result, even when oxidation / reduction is performed at a high doping rate, the battery is heavier due to the large amount of electrolyte used, resulting in a lower energy density. In the case of a Li-ion battery, since lithium ions reciprocate between the positive electrode and the negative electrode (so-called rocking chair type) in accordance with the charge / discharge reaction, the electrolyte concentration is constant regardless of the depth of charge / discharge. The electrolyte required for the Li-ion battery is a small amount (amount that fills between the electrodes). In organic radical batteries, it is necessary to use more electrolytic solution than Li-ion batteries. This contributes to a lower energy density than Li-ion batteries.

  In an organic radical battery, since the electrode active material generally has low conductivity, simply mixing the electrode active material and the conductive material increases the resistance of the electrode and cannot be discharged with a large current. That is, the output performance is reduced.

  The present invention solves the problem that the energy density of the organic radical battery is low and the problem that the resistance increases only by mixing the electrode active material and the conductive material in the form of the electrode. An object of the present invention is to provide a secondary battery capable of discharging with current.

  One aspect of the present invention is a polymer radical material characterized in that a Li metal oxide and a conductive material are incorporated into a polymer radical material having a radical partial structure in a reduced state and are combined. The present invention relates to a Li metal oxide / conductive material composite.

  In one embodiment of the present invention, a raw material solution in which a polymer radical material having a radical partial structure in a reduced state is dissolved or swollen and in which a Li metal oxide and a conductive material are dispersed or dissolved is used as the polymer radical. A precipitate in which the Li metal oxide and the conductive material are taken into the polymer radical material by dropping or pouring the material, the Li metal oxide, and a solution in which the conductive material does not dissolve or swell The polymer radical material / Li metal oxide / conductive material composite obtained as above.

  According to the polymer radical material / Li metal oxide / conductive material composite of the present invention, a secondary battery having a larger energy density and capable of discharging with a large current can be produced.

1 is a perspective view of a laminated secondary battery according to an embodiment of the present invention. 1 is a cross-sectional view of a laminated secondary battery according to an embodiment of the present invention.

  Hereinafter, the present invention will be described in more detail, but the present invention is not limited to the following description, and can be arbitrarily modified and implemented without departing from the gist of the present invention.

[Production Method of Polymer Radical Material / Li Metal Oxide / Conductive Material Composite]
In the method for producing a polymer radical material / Li metal oxide / conductive material composite of the present invention, a polymer radical material having a radical partial structure in a reduced state is dissolved or swollen, and a Li metal oxide and a conductive material are obtained. The raw material solution in which the material is dispersed or dissolved is dropped or poured into a polymer radical material, Li metal oxide, and a solution in which the conductive material does not dissolve or swell, and the polymer radical material, Li metal oxide, and conductive This is a method for producing a precipitate made of a functional material.

  In the present invention, the polymer radical material, the Li metal oxide and the conductive material are uniformly distributed in the composite using the polymer radical material, the Li metal oxide and the conductive material by the above method according to the present invention. To be able to. Therefore, the obtained polymer radical material / Li metal oxide / conductive material composite can have good electron conductivity. As a result, in the electrode manufactured using the polymer radical material / Li metal oxide / conductive material composite, the ratio that can participate in the redox of the radical site of the polymer radical material is increased.

  Therefore, the electrode manufactured by the polymer radical material / Li metal oxide / conductive material composite has a discharge capacity compared to the electrode obtained by simply mixing the polymer radical material, Li metal oxide and conductive material. Becomes larger. In addition, in an electrode using a polymer radical material / Li metal oxide / conductive material composite, the transfer of electrons accompanying the oxidation / reduction of the polymer radical material is smooth through the conductive material. Can be charged and discharged. In addition, a large current can flow at a level of several seconds.

  Hereinafter, each component will be described.

(Polymer radical material)
First, the polymer radical material will be described. As the polymer radical material, a material that can be used as an electrode material of a secondary battery and that has a radical partial structure in a reduced state can be used. More specifically, as shown in the following reaction formula (A), the nitroxyl cation partial structure represented by the chemical formula (1) is taken in the oxidized state, and the nitroxyl radical partial structure represented by the chemical formula (2) is taken in the reduced state. Nitroxyl polymer compounds can be preferably used.

なお、反応式（Ａ）は正極の電極反応を表しており、こうした反応を伴う高分子ラジカル材料は、電子の蓄積と放出を行う二次電池用材料として機能させることができる。反応式（Ａ）に示す酸化還元反応は、有機化合物の構造変化を伴わない反応機構であるため、反応速度が大きく、この高分子ラジカル材料を電極材料として二次電池を構成すれば、一度に大きな電流を流すことが可能となる。

The reaction formula (A) represents the electrode reaction of the positive electrode, and the polymer radical material accompanied with such a reaction can function as a secondary battery material for accumulating and releasing electrons. The oxidation-reduction reaction shown in the reaction formula (A) is a reaction mechanism that does not involve a change in the structure of the organic compound. Therefore, the reaction rate is high. A large current can flow.

  In the present invention, the nitroxyl polymer compound is preferably a polymer compound containing a cyclic nitroxyl structure represented by the chemical formula (3) in the reduced state.

化学式（３）において、Ｒ_１〜Ｒ_４はそれぞれ独立にアルキル基を表し、それぞれ独立に直鎖状のアルキル基が好ましい。また、ラジカルの安定性の観点から、Ｒ_１〜Ｒ_４はそれぞれ独立に炭素数１〜４のアルキル基が好ましく、特にメチル基が好ましい。

In the chemical formula (3), R _{1 to} R ₄ each independently represent an alkyl group, and each independently preferably a linear alkyl group. From the viewpoint of radical stability, R _{1 to} R ₄ are each independently preferably an alkyl group having 1 to 4 carbon atoms, and particularly preferably a methyl group.

  X represents a divalent group such that chemical formula (3) forms a 5- to 7-membered ring. However, at least a part of X constitutes a part of the main chain of the polymer. The structure of X is not particularly limited, but is preferably composed of an element selected from the group consisting of hydrogen, carbon, oxygen, nitrogen, and sulfur.

X represents a divalent group in which the chemical formula (3) forms a 5- to 7-membered ring, and is not particularly limited. Specifically, —CH ₂ CH ₂ —, —CH ₂ CH ₂ CH _2- , —CH ₂ CH ₂ CH ₂ CH ₂ —, —CH═CH—, —CH═CHCH ₂ —, —CH═CHCH ₂ CH ₂ —, —CH ₂ CH═CHCH ₂ — And non-adjacent —CH ₂ — may be replaced by —O—, —NH— or —S—, and —CH═ may be replaced by —N═. The hydrogen atom bonded to the atoms constituting the ring may be substituted with an alkyl group, a halogen atom, ═O, an ether group, an ester group, a cyano group, an amide group, or the like.

Among these, a particularly preferred cyclic nitroxyl structure is a 2,2,6,6-tetramethylpiperidinoxyl radical represented by the chemical formula (6), 2,2,5, represented by the chemical formula (7) in the reduced state. It is selected from the group consisting of a 5-tetramethylpyrrolinoxyl radical and a 2,2,5,5-tetramethylpyrrolinoxyl radical represented by the chemical formula (8). In the chemical formulas (6) to (8), R _{1 to} R ₄ are the same as those in the chemical formula (3).

ただし、上記の化学式（３）で示される環状ニトロキシル構造は、側鎖もしくは主鎖の一部としてポリマーの一部を構成している。すなわち、Ｘの少なくとも一部は、ポリマーの主鎖の一部を構成しており、環状構造を形成する元素に結合する少なくとも１つの水素を取った構造としてポリマーの側鎖もしくは主鎖の一部に存在している。合成等の容易さから側鎖に存在している方が好ましい。側鎖に存在するときは、下記化学式（９）で示される残基のように、化学式（３）で示される環状ニトロキシル構造の基Ｘ中の環員を構成する−ＣＨ_２−、−ＣＨ＝又は−ＮＨ−から水素を取った残基Ｘ’によって主鎖ポリマーに結合している。

However, the cyclic nitroxyl structure represented by the above chemical formula (3) constitutes a part of the polymer as a part of the side chain or main chain. That is, at least a part of X constitutes a part of the main chain of the polymer, and a side chain or a part of the main chain of the polymer as a structure in which at least one hydrogen bonded to the element forming the cyclic structure is removed. Exists. It is preferable that it exists in the side chain from the viewpoint of ease of synthesis. When present in the side chain, like the residue represented by the following chemical formula (9), —CH ₂ —, —CH═ constituting the ring member in the group X of the cyclic nitroxyl structure represented by the chemical formula (3) Alternatively, it is bonded to the main chain polymer by a residue X ′ obtained by removing hydrogen from —NH—.

化学式（９）中、Ｒ_１〜Ｒ_４は前記化学式（３）と同じであり、Ｘ’は前記化学式（３）のＸから水素を取った残基を表したものである。このとき用いられる主鎖ポリマーの構造としては特に制限はなく、どのようなものであっても、化学式（９）で示される残基が側鎖に存在していればよい。具体的には、次に挙げるポリマーに、化学式（９）で示される残基が付加したもの、又はポリマーの一部の原子又は基が、化学式（９）で示される残基によって置換されたものを挙げることができる。いずれの場合も、化学式（９）で示される残基が直接ではなく、適当な２価の基を中間に介して結合していてもよい。

In the chemical formula (9), R _{1 to} R ₄ are the same as those in the chemical formula (3), and X ′ represents a residue obtained by removing hydrogen from X in the chemical formula (3). There is no restriction | limiting in particular as a structure of the main chain polymer used at this time, Whatever is necessary, the residue shown by Chemical formula (9) should just exist in a side chain. Specifically, a polymer represented by the following chemical formula (9) is added to the following polymer, or a part of the polymer atom or group is substituted by a residue represented by the chemical formula (9) Can be mentioned. In any case, the residue represented by the chemical formula (9) may be bonded via an appropriate divalent group in the middle instead of directly.

  Examples of the structure of the main chain polymer include polyalkylene polymers such as polyethylene, polypropylene, polybutene, polydecene, polydodecene, polyheptene, polyisobutene, and polyoctadecene; diene polymers such as polybutadiene, polychloroprene, polyisoprene, and polyisobutene; (Meth) acrylic acid; poly (meth) acrylonitrile; poly (meth) acrylamide polymers such as poly (meth) acrylamide, polymethyl (meth) acrylamide, polydimethyl (meth) acrylamide, polyisopropyl (meth) acrylamide; polymethyl (meta ) Polyalkyl (meth) acrylates such as acrylate, polyethyl (meth) acrylate, polybutyl (meth) acrylate; polyvinylidene fluoride, polytetraph Fluoropolymers such as oloethylene; polystyrene polymers such as polystyrene, polybromostyrene, polychlorostyrene, and polymethylstyrene; polyvinyl acetate, polyvinyl alcohol, polyvinyl chloride, polyvinyl methyl ether, polyvinyl carbazole, polyvinyl pyridine, polyvinyl pyrrolidone, etc. Vinyl polymers: Polyethylene oxide, polypropylene oxide, polybutene oxide, polyoxymethylene, polyacetaldehyde, polymethyl vinyl ether, polypropyl vinyl ether, polybutyl vinyl ether, polybenzyl vinyl ether, and other polyether polymers; polymethylene sulfide, polyethylene sulfide, polyethylene Disulfide, polypropylene sulfide, polypheny Polysulfide polymers such as polyethylene sulfide, polyethylene tetrafluoride, polyethylene trimethylene sulfide; polyesters such as polyethylene terephthalate, polyethylene adipate, polyethylene isophthalate, polyethylene naphthalate, polyethylene paraphenylene diacetate, polyethylene isopropylidene dibenzoate; Polyurethanes such as methylene ethylene urethane; polyketone polymers such as polyether ketone and polyallyl ether ketone; polyanhydride polymers such as polyoxyisophthaloyl; polyamines such as polyethylene amine, polyhexamethylene amine and polyethylene trimethylene amine -Based polymers; polyamide polymers such as nylon, polyglycine, and polyalanine; polyacetylene Polyimine polymers such as minoethylene and polybenzoyliminoethylene; Polyimide polymers such as polyesterimide, polyetherimide, polybenzimide, and polypyromerimide; polyarylene, polyarylene alkylene, polyarylene alkenylene, polyphenol, phenol resin, Cellulose, polybenzimidazole, polybenzothiazole, polybenzoxazine, polybenzoxazole, oricalborane, polydibenzofuran, polyoxoisoindoline, polyfurantetracarboxylic acid diimide, polyoxadiazole, polyoxindole, polyphthalazine, polyphthalide, Polycyanurate, polyisocyanurate, polypiperazine, polypiperidine, polypyrazinoquinoxane, polypyrazole, polypyridazi , Polypyridine, polypyromellitimin, polyquinone, polypyrrolidine, polyquinoxaline, polytriazine, polytriazole and other polyaromatic polymers; polydisiloxane, polydimethylsiloxane and other siloxane polymers; polysilane polymers; polysilazane polymers; poly Examples thereof include phosphazene polymers; polythiazyl polymers; conjugated polymers such as polyacetylene, polypyrrole, and polyaniline. In addition, (meth) acryl means methacryl or acrylic.

  Of these, polyalkylene polymers, poly (meth) acrylic acid, poly (meth) acrylamide polymers, polyalkyl (meth) acrylates, and polystyrene polymers are the main chains because of their excellent electrochemical resistance. It is preferable to have as a structure. The main chain is a carbon chain having the largest number of carbon atoms in the polymer compound. Among these, it is preferable that a polymer is selected so that the unit shown by following Chemical formula (10) can be included in a reduced state.

ここで、化学式（１０）中、Ｒ_１〜Ｒ_４は前記化学式（３）と同じであり、Ｘ’は前記化学式（９）と同じである。Ｒ_５は、水素又はメチル基である。Ｙは特に限定されないが、−ＣＯ−、−ＣＯＯ−、−ＣＯＮＲ_６−、−Ｏ−、−Ｓ−、置換基を有していてもよい炭素数１〜１８のアルキレン基、置換基を有していてもよい炭素数１〜１８のアリーレン基、及びこれらの基の２つ以上を結合させた２価の基を挙げることができる。Ｒ_６は、炭素数１〜１８のアルキル基を表す。化学式（１０）で示される単位で、特に好ましいものは、下記化学式（１１）〜（１３）で示される単位である。

Here, in the chemical formula (10), R _{1 to} R ₄ are the same as the chemical formula (3), and X ′ is the same as the chemical formula (9). R ₅ is hydrogen or a methyl group. Y is not particularly limited, but has —CO—, —COO—, —CONR ₆ —, —O—, —S—, an optionally substituted alkylene group having 1 to 18 carbon atoms, and a substituent. And an arylene group having 1 to 18 carbon atoms which may be used, and a divalent group formed by bonding two or more of these groups. R ₆ represents an alkyl group having 1 to 18 carbon atoms. Among the units represented by the chemical formula (10), particularly preferred are the units represented by the following chemical formulas (11) to (13).

化学式（１１）〜（１３）において、Ｒ_１〜Ｒ_４は前記化学式（３）と同じであり、Ｙは上記化学式（１０）と同じであるが特に−ＣＯＯ−、−Ｏ−及び−ＣＯＮＲ_６−のいずれかが好ましい。

In the chemical formulas (11) to (13), R _{1 to} R ₄ are the same as the chemical formula (3), and Y is the same as the chemical formula (10), but in particular —COO—, —O—, and —CONR _6. -Is preferred.

  In the present invention, the residue represented by the chemical formula (9) may not be present in all of the side chains. For example, all of the units constituting the polymer may be units represented by the chemical formula (10), or some of them may be units represented by the chemical formula (10). The amount contained in the polymer varies depending on the purpose, the structure of the polymer, and the production method, but it may be present even in a slight amount. There is no particular restriction on the synthesis of the polymer, and when it is desired to obtain as large a power storage effect as possible, it is preferably 50% by mass or more, particularly 80% by mass or more.

Hereinafter, examples of units possessed by the nitroxyl polymer preferably used in the present invention include a polymer compound represented by the chemical structure of the following chemical formula (4) and / or (5), or a chemical structure thereof as a repeating unit. Mention may be made of copolymers. In the chemical formulas (4) and (5), R _{1 to} R ₄ are the same as those in the chemical formula (3), and R ₅ is hydrogen or a methyl group.

  The molecular weight of the nitroxyl polymer in the present invention is not particularly limited, but preferably has a molecular weight that does not dissolve in the electrolyte when a secondary battery is constructed. It depends on the combination. In general, the weight average molecular weight is 1,000 or more, preferably 10,000 or more, particularly preferably 20,000 or more, and 5,000,000 or less, preferably 500,000 or less. Moreover, the polymer containing the residue represented by the chemical formula (9) may be cross-linked, thereby improving the durability against the electrolyte.

  The nitroxyl polymer compound can be used alone, but two or more kinds may be mixed.

(Li metal oxide)
As the Li metal oxide used in the present invention, an electrode active material used in a Li ion battery can be used. For example, lithium manganate having a layered structure such as LiMnO ₂ or Li _x Mn ₂ O ₄ (0 <x <2) or a spinel structure; Li transition metal composite oxide having a layered structure such as LiCoO ₂ or LiNiO ₂ ; Li Examples include _y V ₂ O ₅ (0 <y <2); olivine-based materials such as LiFePO ₄ . A material obtained by substituting a part of these compounds with another element can also be used. For example, a material obtained by substituting a part of Mn in lithium manganate having a spinel structure with another transition metal, such as LiNi _{0. 5} Mn _1.5 O ₄ , LiCr _0.5 Mn _1.5 O ₄ , LiCo _0.5 Mn _1.5 O ₄ , LiCoMnO ₄ , LiNi _0.5 Mn _1.5-z Ti _z O ₄ (0 < z <1.5); a material obtained by substituting a part of the transition metal of the Li transition metal composite oxide having a layered structure with another element, for example, LiNi _0.5 Mn _0.5 O ₂ , LiNi _0.33 Mn _{0. 33} Co _0.33 O ₂ , LiNi _0.8 Co _0.2 O ₂ , LiNi _x Al _1-x O ₂ (0 <x <1); LiMPO ₄ (M is represented by Fe, Mn, Ni, Co) At least one Olivine materials represented by.) And the like. These may be non-stoichiometric compositions such as Li-rich compositions. Among these, it is particularly preferable to use LiFePO ₄ , lithium manganate, and LiCoO ₂ . In this invention, these can also be used in combination of 2 or more types.

(Conductive material)
Next, the conductive material will be described. As the conductive material, fine particles, powders, fibers, tubes, etc. having conductivity that can be incorporated into the polymer radical material to develop good electronic conductivity in the composite. Various conductive materials can be used as long as they are materials. For example, a carbon material, a conductive inorganic material, a conductive polymer material, and the like can be given. Among these, a carbon material is preferable, and specifically, at least one selected from the group consisting of natural graphite, artificial graphite, carbon black, vapor-grown carbon fiber, mesophase pitch carbon fiber, and carbon nanotube is preferable. . These conductive materials may be used in a mixture of two or more at any ratio within the scope of the gist of the present invention.

  The size of the conductive material is not particularly limited, but it is preferably as fine as possible from the viewpoint of uniform dispersion. For example, the particle size in the case of fine particles is preferably an average particle size of primary particles of 500 nm or less, and may be a fiber or tube In the case of the material, the diameter is preferably 500 nm or less, and the length is preferably 5 nm or more and 50 μm or less. Here, the average particle diameter and each dimension are average values obtained by observation in an electron microscope, or values measured by a D50 value particle size distribution system of particle size distribution measured by a laser diffraction particle size distribution measuring device. .

  Such a conductive material may or may not be dissolved in the solvent constituting the raw material solution, as will be described later in the section of the manufacturing method. However, the polymer radical material, Li metal oxide in the raw material solution may be used. The solution for producing the conductive material as a precipitate needs to have a property that all these materials do not dissolve or swell. Usually, Li metal oxides, carbon materials with good conductivity, and inorganic materials are not dissolved in the raw material solution or the solution for generating a precipitate, but are mostly dispersed.

(Production method)
In the production method of the polymer radical material / Li metal oxide / conductive material composite, the polymer radical material having a radical partial structure in the reduced state is dissolved or swollen and the Li metal oxide and the conductive material are dispersed. Alternatively, the dissolved raw material solution is dropped or poured into a solution in which the polymer radical material, Li metal oxide and conductive material do not dissolve or swell, and the precipitate is composed of the polymer radical material, Li metal oxide and conductive material. This is a method for generating a product.

  Since the polymer radical material, the Li metal oxide, and the conductive material are as described above, other configurations will be described below.

  The solvent constituting the raw material solution of the polymer radical material / Li metal oxide / conductive material composite needs to be a solvent capable of dissolving or swelling the polymer radical material described above. Usually, Li metal oxide and carbon materials and inorganic materials with good conductivity are often insoluble in a solvent, and therefore the solvent does not necessarily have to dissolve Li metal oxide or conductive material. However, it is necessary to disperse. Specific examples of such a solvent include N-methylpyrrolidone, tetrahydrofuran, toluene, xylene and the like. Among these, N-methylpyrrolidone is preferable.

  In the preparation of the raw material solution, usually, the polymer radical material is first dissolved and swollen in a solvent capable of dissolving or swelling the polymer radical material. There, Li metal oxide and a conductive material are added and stirred.

  The amount of the conductive material to be added is adjusted in consideration of electronic conductivity and the like, but usually 5 parts by weight or more and 200 parts by weight or less, preferably 7 parts by weight when the polymer radical material is 100 parts by weight. More than 100 parts by weight and more preferably 10 parts by weight or more and 50 parts by weight or less. With this blending amount, the conductivity of the obtained electrode is easily made sufficient, the amount of the polymer radical material is not relatively reduced, and the battery capacity is easily secured.

  The amount of Li metal oxide to be added is usually 1 part by weight or more and 500 parts by weight or less, preferably 3 parts by weight or more and 300 parts by weight or less, more preferably 5 parts by weight, when the polymer radical material is 100 parts by weight. It mix | blends in the range below 200 weight part or less. With this blending amount, it becomes easy to obtain a sufficient capacity density and battery capacity per weight of the electrode active material.

  In the present invention, the term “dissolving” of the polymer radical material includes not only literally dissolving, but also includes a mode in which the polymer radical material is compatible with fluidity, and “swelling” is a general term. Even if it is not solubilized, it includes a mode in which the conductive material becomes a so-called swollen state by being mixed with the conductive material, and is mixed with the conductive material so that the conductive material is uniformly dispersed in the polymer radical material. In addition, the “dispersion” of the conductive material includes, for example, a mode in which an insoluble material is dispersed in a solvent such as a carbon material, and the “dissolution” of the conductive material is literally dissolved in the solvent. It is intended to include compatible aspects.

  A stirring / mixing device such as a homogenizer can be used as an apparatus used to mix the polymer radical material, the Li metal oxide, and the conductive material. By mixing using such an apparatus, a slurry-like raw material solution in which the conductive material is uniformly dispersed in the solution in which the polymer radical material is dissolved or swollen is obtained.

  The raw material solution thus obtained is dropped or poured little by little into a solvent (poor solvent) in which the polymer radical material, the Li metal oxide, and the conductive material do not dissolve or swell. By doing so, the polymer radical material, the Li metal oxide and the conductive material can be precipitated simultaneously. Examples of the solvent (poor solvent) in which the polymer radical material, the Li metal oxide, and the conductive material do not dissolve or swell include methanol, ethanol, dimethyl ether, ethyl methyl ether, diethyl ether, hexane, heptane, and the like. Among these, methanol is preferable.

  The poor solvent is selected mainly in relation to the polymer radical material, and in the present invention, mainly methanol or the like is preferably used, but other solvents may be used as long as they function as a poor solvent. Li metal oxides and conductive materials are generally difficult to dissolve in organic solvents, so they are not considered much. However, Li metal oxides and conductive materials are solvents that do not dissolve or swell. is necessary.

  A raw material solution is dropped or poured little by little in such a poor solvent to produce a precipitate, but the manner of dripping or pouring (the amount of dripping, the dropping speed, etc.) depends on the characteristics and form of the resulting precipitate. Adjusted. In particular, in the present invention, it is desirable that the Li metal oxide and the conductive material be obtained as a precipitate taken in a state in which the Li metal oxide and the conductive material are uniformly dispersed inside the polymer radical material. It is desirable.

  The obtained precipitate is collected by filtration or the like and dried to obtain a polymer radical material / Li metal oxide / conductive material composite. The obtained polymer radical material / Li metal oxide / conductive material composite may be pulverized by pulverization or the like.

  As described above, according to the method for producing a polymer radical material / Li metal oxide / conductive material composite of the present invention, the Li metal oxide and the conductive material are uniformly dispersed in the polymer radical material. Can do. In the composite obtained by such a manufacturing method, the Li metal oxide or the conductive material is obtained as a precipitate taken into the polymer radical material, so that the composite can have good electronic conductivity. .

[Secondary battery]
The secondary battery of the present invention uses the polymer radical material / Li metal oxide / conductive material composite of the present invention as an electrode material. The secondary battery constructed using the electrode using the polymer radical material / Li metal oxide / conductive material composite of the present invention is simply a mixture of polymer radical material, Li metal oxide and conductive material. The discharge capacity is larger than that of a secondary battery configured using the electrode obtained in this manner, and a large current can be passed at a level of several seconds.

  In a preferred embodiment of the secondary battery of the present invention, the electrode using the polymer radical material / Li metal oxide / conductive material composite is the positive electrode.

  In a preferred embodiment of the secondary battery of the present invention, the electrode using the polymer radical material / Li metal oxide / conductive material composite is a positive electrode, and the negative electrode is capable of reversibly carrying lithium ions. And an aprotic organic solvent containing a lithium salt is used for the electrolyte.

  Moreover, in a preferable aspect of the secondary battery of the present invention, the battery further includes a lithium ion supply source, and the positive electrode and / or the negative electrode each include a current collector having holes penetrating the front and back surfaces, and the negative electrode and the negative electrode The negative electrode is pre-doped with lithium ions by electrochemical contact with a lithium ion source.

  In the present invention, the shape of the secondary battery is not particularly limited, and a conventionally known battery can be used. Examples of the shape of the secondary battery include an electrode laminate or a wound body sealed with a metal case, a resin case, or a laminate film made of a metal foil such as an aluminum foil and a synthetic resin film, etc. A mold, a square, a coin, a sheet, and the like are manufactured, but the present invention is not limited to these.

(Method for manufacturing secondary battery)
The method for producing the secondary battery is not particularly limited, and a method appropriately selected according to the material can be used. For example, a solvent is added to an electrode active material, a conductivity-imparting agent, etc. to form a slurry, which is applied to an electrode current collector, and the electrode is produced by heating or volatilizing the solvent at room temperature, and this electrode is sandwiched between a counter electrode and a separator. And then wrapped or wrapped in an outer package, and an electrolyte solution is injected and sealed. Solvents for slurrying include ether solvents such as tetrahydrofuran, diethyl ether, ethylene glycol dimethyl ether and dioxane; amine solvents such as N, N-dimethylformamide and N-methylpyrrolidone; aromatics such as benzene, toluene and xylene. Aliphatic hydrocarbon solvents such as hexane and heptane; halogenated hydrocarbon solvents such as chloroform, dichloromethane, dichloroethane, trichloroethane, and carbon tetrachloride; alkyl ketone solvents such as acetone and methyl ethyl ketone; methanol, Examples include alcohol solvents such as ethanol and isopropyl alcohol; dimethyl sulfoxide, water and the like. In addition, as a method for manufacturing an electrode, there is a method in which an electrode active material, a conductivity-imparting agent, and the like are kneaded in a dry method and then thinned and laminated on an electrode current collector. In the production of electrodes, in particular, in the case of a method in which a solvent is added to an organic electrode active material, a conductivity imparting agent, etc. and applied to an electrode current collector, and the solvent is volatilized by heating or at room temperature, peeling of the electrode, cracking, etc. Is likely to occur. When the polymer radical material / Li metal oxide / conductive material composite of the present invention is used, and an electrode having a thickness of preferably 40 μm or more and 300 μm or less is produced, the electrode is not easily peeled off or cracked, and is uniform. It has the feature that an electrode can be manufactured.

When manufacturing a secondary battery, the secondary battery is manufactured using the radical radical of the polymer radical material described above as the electrode active material, and the electrode of the present invention can be used to produce the secondary battery. In some cases, a secondary battery is manufactured using a polymer that changes to a radical compound. Examples of the polymer that changes to the polyradical compound by such an electrode reaction include a lithium salt or sodium salt composed of an anion body obtained by reducing the polyradical compound and an electrolyte cation such as lithium ion or sodium ion, or the above-mentioned polyradical compound and a cation body oxidized PF ₆ ^- or BF ₄ ^-, etc. salt comprising the electrolyte anions such like.

  In the present invention, a conventionally known method can be used as a method for manufacturing a secondary battery for other manufacturing conditions such as taking out a lead from an electrode and packaging.

  FIG. 1 shows a perspective view of an example of a laminated secondary battery according to the present embodiment, and FIG. 2 shows a cross-sectional view. As shown in these drawings, the secondary battery 107 has a laminated structure including a positive electrode 101, a negative electrode 102 facing the positive electrode, and a separator 105 sandwiched between the positive electrode and the negative electrode. Covered with the exterior film 106, the electrode lead 104 is drawn out of the exterior film 106. An electrolytic solution is injected into the secondary battery. Below, the structural member and manufacturing method of a secondary battery are demonstrated in detail.

(Positive electrode)
The positive electrode 101 includes a polymer radical material / Li metal oxide / conductive material composite, and further includes a conductivity imparting agent and a binder as necessary, and is formed on one current collector 103. .

(Negative electrode)
The negative electrode 102 includes a negative electrode active material, and further includes a conductivity imparting agent and a binder as necessary, and is formed on the other current collector 103.

  The negative electrode active material of the secondary battery of the present invention is not particularly limited as long as it can be used as the negative electrode active material of a lithium secondary battery. For example, it has been conventionally used as a negative electrode active material. Examples include graphite, amorphous carbon, lithium metal, lithium titanate, titanium oxide, silicon and its oxides and alloys, germanium and its alloys, tin and its oxides and alloys. In addition, any substance that electrochemically inserts and desorbs lithium can be used without limitation. These negative electrode active materials can be used alone or in combination.

(Separator)
An insulating porous separator 105 is provided between the positive electrode 101 and the negative electrode 102 to insulate and separate them. As the separator 105, a porous resin film made of polyethylene, polypropylene, or the like, a cellulose film, a non-woven cloth, or the like can be used.

(Electrolyte)
The electrolytic solution transports charge carriers between the positive electrode and the negative electrode, and is impregnated in the positive electrode 101, the negative electrode 102, and the separator 105. As the electrolytic solution, one having an ion conductivity of 10 ⁻⁵ to 10 ⁻¹ S / cm at 20 ° C. can be used, and a nonaqueous electrolytic solution in which an electrolyte salt is dissolved in an organic solvent is used. it can. As the solvent for the electrolytic solution, an aprotic organic solvent can be used.

Examples of the electrolyte salt include LiPF ₆ , LiClO ₄ , LiBF ₄ , LiCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ (hereinafter “LiTFSI”), LiN (C ₂ F ₅ SO ₂ ) ₂ (hereinafter “LiBETI”). ), Li (CF ₃ SO ₂ ) ₃ C, Li (C ₂ F ₅ SO ₂ ) ₃ C, or other ordinary electrolyte materials can be used.

  Examples of the organic solvent include cyclic carbonates such as ethylene carbonate, propylene carbonate, and butylene carbonate; chain carbonates such as dimethyl carbonate, diethyl carbonate, and methyl ethyl carbonate; γ-lactones such as γ-butyrolactone; cyclics such as tetrahydrofuran and dioxolane. Ethers; amides such as dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone and the like. As another organic solvent, it is preferable to mix at least one of a cyclic carbonate and a chain carbonate.

(Current collector)
The current collector of the lithium secondary battery of the present invention is not particularly limited as long as it is formed from a metal that does not alloy with lithium. For example, aluminum that has been conventionally used as a positive electrode current collector, and a negative electrode current collector Examples include copper and alloys thereof, nickel, and the like.

(Exterior film)
As the exterior film 106, an aluminum laminate film or the like can be used. Examples of the exterior body other than the exterior film include a metal case and a resin case. Examples of the outer shape of the secondary battery include a cylindrical shape, a square shape, a coin shape, and a sheet shape.

(Example of secondary battery production)
The positive electrode 101 is placed on the exterior film 106 and overlapped with the negative electrode 102 with the separator 105 interposed therebetween to obtain an electrode laminate. The obtained electrode laminate is covered with an exterior film 106, and three sides including the electrode lead portion are heat-sealed. An electrolyte is injected into this and vacuum impregnated. After sufficiently impregnating and filling the gap between the electrode and the separator 105 with the electrolytic solution, the remaining fourth side is heat-sealed to obtain a laminated secondary battery 107.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

Example 1
<Production of polymer radical material / Li metal oxide / carbon material composite>
10.0 g of the nitroxyl polymer compound of the above chemical formula (4) (weight average molecular weight: 28000, theoretical capacity density 111 mAh / g) in which R _{1 to} R ₅ are methyl groups was dissolved in 150 ml of N-methylpyrrolidone. To this was added olivine-type lithium iron phosphate (LiFePO ₄ , theoretical capacity density 155 mAh / g) 10.0 g and carbon material (product name: VGCF-H) 2.8 g, and the mixture was stirred with a homogenizer. A slurry in which the carbon material was uniformly dispersed was obtained.

  Next, this slurry was gradually added to 1 L of methanol with stirring to precipitate a nitroxyl polymer compound / Li metal oxide / carbon material composite. The precipitate was filtered, and further vacuum-dried at 60 ° C. for 8 hours with a vacuum drier to obtain a solid of a nitroxyl polymer compound / Li metal oxide / carbon material composite. This was ground in a mortar to make a powder.

<Production of secondary battery>
9.5 g of the nitroxyl polymer compound / olivine-type lithium iron phosphate / carbon material composite obtained as described above, 400 mg of carboxymethyl cellulose (CMC), 100 mg of polytetrafluoroethylene (PTFE), and 30 ml of water were stirred with a homogenizer. To prepare a uniform paste. This slurry was applied on an aluminum foil as a positive electrode current collector, and further dried at 100 ° C. for 10 minutes to obtain an electrode having a thickness of 130 μm. This was cut into a 22 × 24 mm rectangle and used as the positive electrode.

In a dry room with a dew point of −50 ° C. or lower, the positive electrode prepared by the above method and a copper foil (negative electrode, 22 × 24 mm) laminated with a metal lithium foil are sequentially stacked via a separator to produce an electrode laminate. did. The positive electrode lead was ultrasonically welded to the aluminum foil as the positive electrode current collector, and the negative electrode lead was similarly welded to the copper foil as the negative electrode current collector. They were covered with an aluminum laminate film (exterior body) having a thickness of 100 μm, and three sides including the lead portion were heat-sealed first. Next, a mixed electrolyte solution of ethylene carbonate (EC) / diethyl carbonate (DEC) (EC / EDC = 3/7) containing 1 mol / L LiPF ₆ was injected and impregnated in the electrode. Finally, the last four sides were thermally fused under reduced pressure to produce a secondary battery (the same type as the secondary battery 107 shown in FIG. 1).

<Discharge test>
After producing the secondary battery, the battery was charged to 4.0 V at a constant current of 0.5 mA at 20 ° C., and then discharged to 2.5 V. Thereafter, the battery was charged again to 4.2 V at 0.5 mA, and then discharged to 2.5 V at 0.5 mA, and the battery capacity at this time was measured. The battery capacity was 2.4 mAh. The capacity density per weight of the electrode active material (nitroxyl polymer compound + LiFePO ₄ ) at this time was 120 mAh / g.

  Subsequently, the battery was charged at 20 ° C. with a constant current of 0.5 mA until the voltage became 4.0 V, and then discharged at 10 mA for 1 second. The battery was charged again at a constant current of 0.5 mA until the voltage reached 4.0 V, and then discharged at 20 mA for 1 second. This charging / discharging was repeated while changing the discharge current to 30, 40, ..., 1000 mA. The output was obtained by multiplying the discharge end voltage and the measured current. The largest output among the outputs at each discharge current was defined as the maximum output. The maximum output was 837 mW.

(Example 2)
<Production of polymer radical material / Li metal oxide / carbon material composite>
A polymer radical in the same manner as in Example 1 except that a nitroxyl polymer compound of the above chemical formula (5) (weight average molecular weight: 12000, theoretical capacity density 134 mAh / g) in which R _{1 to} R ₅ are methyl groups is used. A material / Li metal oxide / carbon material composite was prepared.

<Production of secondary battery>
A secondary battery was fabricated in the same manner as in Example 1 using the nitroxyl polymer compound / olivine-type lithium iron phosphate / carbon material composite obtained as described above.

<Discharge test>
After producing the secondary battery, the battery was charged to 4.0 V at a constant current of 0.5 mA at 20 ° C., and then discharged to 2.5 V. Thereafter, the battery was charged again to 4.2 V at 0.5 mA, and then discharged to 2.5 V at 0.5 mA, and the battery capacity at this time was measured. The battery capacity was 2.7 mAh. The capacity density per weight of the electrode active material (nitroxyl polymer compound + LiFePO ₄ ) at this time was 138 mAh / g.

  Subsequently, the battery was charged at 20 ° C. with a constant current of 0.5 mA until the voltage became 4.0 V, and then discharged at 10 mA for 1 second. The battery was charged again at a constant current of 0.5 mA until the voltage reached 4.0 V, and then discharged at 20 mA for 1 second. This charging / discharging was repeated while changing the discharge current to 30, 40, ..., 1000 mA. The output was obtained by multiplying the discharge end voltage and the measured current. The largest output among the outputs at each discharge current was defined as the maximum output. The maximum output was 1046 mW.

(Comparative Example 1)
<Production of secondary battery>
17.9 g of nitroxyl polymer compound (weight average molecular weight: 28000) of the above chemical formula (4), wherein R _{1 to} R ₅ are methyl groups, carbon material (trade name: VGCF-H, manufactured by Showa Denko), CMC 400 mg Then, 100 mg of PTFE and 30 ml of water were stirred with a homogenizer to prepare a uniform paste. This slurry was applied onto an aluminum foil as a positive electrode current collector, and further dried at 100 ° C. for 10 minutes to form a positive electrode having a thickness of 130 μm. A secondary battery was fabricated by the same configuration and method as in Example 1 except that the manufactured positive electrode was used.

<Discharge test>
After producing the secondary battery, the battery was charged to 4.0 V at a constant current of 0.5 mA at 20 ° C., and then discharged to 2.5 V. Thereafter, the battery was charged again to 4.2 V at 0.5 mA, and then discharged to 2.5 V at 0.5 mA, and the battery capacity at this time was measured. The battery capacity was 2.7 mAh. The capacity density per weight of the electrode active material (nitroxyl polymer compound) at this time was 90 mAh / g.

  Subsequently, the battery was charged at 20 ° C. with a constant current of 0.5 mA until the voltage became 4.0 V, and then discharged at 10 mA for 1 second. The battery was charged again at a constant current of 0.5 mA until the voltage reached 4 V, and then discharged at 20 mA for 1 second. This charging / discharging was repeated while changing the discharge current to 30, 40, ..., 1000 mA. The output was obtained by multiplying the discharge end voltage and the measured current. The largest output among the outputs at each discharge current was defined as the maximum output. The maximum output was 280 mW.

(Comparative Example 2)
<Production of secondary battery>
8. 95 g of the nitroxyl polymer compound (weight average molecular weight: 28000) of the above chemical formula (4) in which R _{1 to} R ₅ are methyl groups, 8.95 g of olivine type lithium iron phosphate, carbon material (trade name, manufactured by Showa Denko) : VGCF-H) 2.5 g, CMC 400 mg, PTFE 100 mg, and water 30 ml were stirred with a homogenizer to prepare a uniform paste. This slurry was applied onto an aluminum foil as a positive electrode current collector, and further dried at 100 ° C. for 10 minutes to form a positive electrode having a thickness of 130 μm. A secondary battery was fabricated by the same configuration and method as in Example 1 except that the manufactured positive electrode was used.

<Discharge test>
After producing the secondary battery, the battery was charged to 4.0 V at a constant current of 0.5 mA at 20 ° C., and then discharged to 2.5 V. Thereafter, the battery was charged again to 4.2 V at 0.5 mA, and then discharged to 2.5 V at 0.5 mA, and the battery capacity at this time was measured. The battery capacity was 2.7 mAh. The capacity density per weight of the electrode active material (nitroxyl polymer compound + LiFePO ₄ ) at this time was 56 mAh / g.

  Subsequently, the battery was charged at 20 ° C. with a constant current of 0.5 mA until the voltage became 4.0 V, and then discharged at 10 mA for 1 second. The battery was charged again at a constant current of 0.5 mA until the voltage reached 4.0 V, and then discharged at 20 mA for 1 second. This charging / discharging was repeated while changing the discharge current to 30, 40, ..., 1000 mA. The output was obtained by multiplying the discharge end voltage and the measured current. The largest output among the outputs at each discharge current was defined as the maximum output. The maximum output was 314 mW.

  The results of the discharge test are shown in Table 1.

  In Examples 1 and 2, both the capacity density and the maximum output were excellent as compared with the comparative example. This is because the nitroxyl polymer compound, lithium iron phosphate, and the conductive material are uniformly dispersed in the positive electrode by compounding the nitroxyl polymer compound, lithium iron phosphate and the conductive material, and good electronic conductivity is obtained. This is considered to be due to the fact that a faster reaction was possible and discharge with a large current was possible.

  The main invention of the present application is as described in the scope of claims, but the following matters are also disclosed.

  (Appendix 1) A raw material solution in which a polymer radical material having a radical partial structure in a reduced state is dissolved or swollen and a Li metal oxide and a conductive material are dispersed or dissolved is prepared. Precipitation comprising the polymer radical material, the Li metal oxide, and the conductive material by dropping or pouring the polymer radical material, the Li metal oxide, and the conductive material into a solution that does not dissolve or swell. A method for producing a polymer radical material / Li metal oxide / conductive material composite characterized in that a product is produced.

  (Supplementary Note 2) The polymer radical material has a nitroxyl cation partial structure represented by the following chemical formula (1) in the oxidized state and a nitroxyl radical partial structure represented by the following chemical formula (2) in the reduced state. The method for producing a polymer radical material / Li metal oxide / conductive material composite according to Appendix 1, which is a molecular compound.

  (Appendix 3) The polymer radical material, Li metal oxide, and conductivity according to Appendix 2, wherein the nitroxyl polymer compound is a polymer compound containing a cyclic nitroxyl structure represented by the following chemical formula (3) in a reduced state: A method for producing a material composite.

（化学式（３）中、Ｒ₁〜Ｒ₄はそれぞれ独立にアルキル基を表し、Ｘは化学式（３）が５〜７員環を形成するような２価の基を表す。ただし、Ｘの少なくとも一部は、ポリマーの主鎖の一部を構成している。）

(In the chemical formula (3), R _{1 to} R ₄ each independently represents an alkyl group, and X represents a divalent group such that the chemical formula (3) forms a 5- to 7-membered ring, provided that at least X Some constitute part of the main chain of the polymer.)

  (Additional remark 4) The said high molecular radical material is the high molecular compound represented by the chemical structure of following Chemical formula (4) and / or (5), or a copolymer containing this chemical structure as a repeating unit. A method for producing a polymer radical material / Li metal oxide / conductive material composite described in 1.

（化学式（４）及び（５）中、Ｒ_１〜Ｒ_４はそれぞれ独立にアルキル基を表し、Ｒ_５は水素又はメチル基を表す。）

(In chemical formulas (4) and (5), R _{1 to} R ₄ each independently represents an alkyl group, and R ₅ represents hydrogen or a methyl group.)

  (Supplementary Note 5) A raw material solution in which a polymer radical material having a radical partial structure in a reduced state is dissolved or swollen and Li metal oxide and a conductive material are dispersed or dissolved is used as the polymer radical material, The Li metal oxide and the conductive material are dropped or poured into a solution that does not dissolve or swell, and the Li metal oxide and the conductive material are obtained as a precipitate taken into the polymer radical material. Polymer radical material / Li metal oxide / conductive material composite.

  (Appendix 6) The high molecular radical material has a nitroxyl cation partial structure represented by the following chemical formula (1) in the oxidized state and a nitroxyl radical partial structure represented by the following chemical formula (2) in the reduced state. The polymer radical material / Li metal oxide / conductive material composite according to Appendix 5, which is a molecular compound.

  (Appendix 7) The polymer radical material, Li metal oxide, and conductivity according to appendix 6, wherein the nitroxyl polymer compound is a polymer compound containing a cyclic nitroxyl structure represented by the following chemical formula (3) in a reduced state: Material composite.

（化学式（３）中、Ｒ_１〜Ｒ_４はそれぞれ独立にアルキル基を表し、Ｘは化学式（３）が５〜７員環を形成するような２価の基を表す。ただし、Ｘの少なくとも一部は、ポリマーの主鎖の一部を構成している。）

(In the chemical formula (3), R _{1 to} R ₄ each independently represents an alkyl group, and X represents a divalent group such that the chemical formula (3) forms a 5- to 7-membered ring. Some constitute part of the main chain of the polymer.)

  (Additional remark 8) The said high molecular radical material is the high molecular compound represented by the following chemical formula (4) and / or the chemical structure of (5), or a copolymer containing this chemical structure as a repeating unit. Polymer radical material / Li metal oxide / conductive material composite as described in 1.

（化学式（４）及び（５）中、Ｒ_１〜Ｒ_４はそれぞれ独立にアルキル基を表し、Ｒ_５は水素又はメチル基を表す。）

(In chemical formulas (4) and (5), R _{1 to} R ₄ each independently represents an alkyl group, and R ₅ represents hydrogen or a methyl group.)

  (Supplementary note 9) The supplementary notes 5 to 8, wherein the conductive material is at least one selected from the group consisting of natural graphite, artificial graphite, carbon black, vapor-grown carbon fiber, mesophase pitch carbon fiber, and carbon nanotube. The polymer radical material / Li metal oxide / conductive material composite according to any one of the above items.

(Supplementary Note 10) The Li metal oxide _{LiMnO 2, Li x Mn 2 O} 4 (0 <x <2), LiCoO 2, LiNiO 2, Li y V 2 O 5 (0 <y <2), LiFePO 4, LiNi _0.5 Mn _1.5 O ₄ , LiCr _0.5 Mn _1.5 O ₄ , LiCo _0.5 Mn _1.5 O ₄ , LiCoMnO ₄ , LiNi _0.5 Mn _0.5 O ₂ , LiNi _{0. 33} Mn _0.33 Co _0.33 O ₂ , LiNi _0.8 Co _0.2 O ₂ , LiNi _0.5 Mn _1.5-z Ti _z O ₄ (0 <z <1.5) and LiNi _x Al The polymer radical material / Li metal oxide / conductive material composite according to any one of appendices 5 to 9, which is at least one selected from the group consisting of _{1-xO 2} (0 <x <1) body.

  (Appendix 11) A secondary battery using the polymer radical material / Li metal oxide / conductive material composite according to any one of appendices 5 to 10 as an electrode material.

  (Additional remark 12) The secondary battery of Additional remark 11 whose said electrode is a positive electrode.

  (Supplementary note 13) The secondary battery according to supplementary note 12, wherein the electrode is a positive electrode, and the negative electrode includes a substance capable of reversibly supporting lithium ions, and the electrolyte uses an aprotic organic solvent including a lithium salt.

  (Additional remark 14) The lithium ion supply source is further provided, The said positive electrode and / or the said negative electrode are each equipped with the electrical power collector which has the hole which penetrates front and back, respectively, Electrochemistry of the said negative electrode and the said lithium ion supply source The secondary battery according to appendix 13, wherein the negative electrode is previously doped with lithium ions by mechanical contact.

  Since the secondary battery in the present invention can simultaneously achieve high energy density and high output characteristics, power sources for various portable electronic devices such as notebook PCs, mobile phones, and smartphones that require high energy density, electric vehicles, and high output are required. It can be used for a drive or auxiliary storage power source of a hybrid electric vehicle or the like, a power storage device for various energy such as solar energy and wind power generation.

DESCRIPTION OF SYMBOLS 101 Positive electrode 102 Negative electrode 103 Current collector 104 Electrode lead 105 Separator 106 Exterior film 107 Laminate type secondary battery

Claims (10)

Li metal oxides and conductive material, characterized in that it is Oite dispersed within the polymer radical material take radical partial structure in the reduced state, polymeric radical material, Li metal oxides, electrically conductive material Complex.   The polymer radical material / Li metal oxide / conductive material composite according to claim 1, wherein the Li metal oxide and the conductive material are uniformly dispersed inside the polymer radical material. The polymer radical material is a nitroxyl polymer compound having a nitroxyl cation partial structure represented by the following chemical formula (1) in an oxidized state and a nitroxyl radical partial structure represented by the following chemical formula (2) in a reduced state. The polymer radical material / Li metal oxide / conductive material composite according to claim 1 or 2.

4. The polymer radical material according to claim 3, wherein the polymer radical material is a polymer compound represented by a chemical structure represented by the following chemical formula (4) and / or (5), or a copolymer containing the chemical structure as a repeating unit. Polymer radical material / Li metal oxide / conductive material composite.

(In chemical formulas (4) and (5), R _{1 to} R ₄ each independently represents an alkyl group, and R ₅ represents hydrogen or a methyl group.)   The conductive material is at least one selected from the group consisting of natural graphite, artificial graphite, carbon black, vapor-grown carbon fiber, mesophase pitch carbon fiber, and carbon nanotube. The polymer radical material / Li metal oxide / conductive material composite according to the item. The Li metal oxide is _{LiMnO 2, Li x Mn 2 O} 4 (0 <x <2), LiCoO 2, LiNiO 2, Li y V 2 O 5 (0 <y <2), LiFePO 4, LiNi 0.5 Mn _1.5 O ₄ , LiCr _0.5 Mn _1.5 O ₄ , LiCo _0.5 Mn _1.5 O ₄ , LiCoMnO ₄ , LiNi _0.5 Mn _0.5 O ₂ , LiNi _0.33 Mn _{0, 33} Co _0.33 O ₂ , LiNi _0.8 Co _0.2 O ₂ , LiNi _0.5 Mn _1.5-z Ti _z O ₄ (0 <z <1.5) and LiNi _x Al _1-x O _2. The polymer radical material / Li metal oxide / conductive material composite according to claim 1, which is at least one selected from the group consisting of ₂ (0 <x <1).   A secondary battery using the polymer radical material / Li metal oxide / conductive material composite according to claim 1 as an electrode material.   The secondary battery according to claim 7, wherein the electrode is a positive electrode. Preparing a raw material solution in which a polymer radical material having a radical partial structure in a reduced state is dissolved or swollen and in which a Li metal oxide and a conductive material are dispersed or dissolved;
The polymer radical material, the Li metal oxide, and the conductive material are dropped or poured into the solution in which the polymer radical material, the Li metal oxide, and the conductive material do not dissolve or swell. A method for producing a polymer radical material / Li metal oxide / conductive material composite, characterized in that a precipitate comprising: The polymer radical material is a nitroxyl polymer compound having a nitroxyl cation partial structure represented by the following chemical formula (1) in an oxidized state and a nitroxyl radical partial structure represented by the following chemical formula (2) in a reduced state. The method for producing a polymer radical material / Li metal oxide / conductive material composite according to claim 9.

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