JP4752218B2 - Electrode active material, battery and polyradical compound - Google Patents

Description

  The present invention provides an electrode active material having a high capacity density and capable of extracting a large current, a battery having a high energy density and a large output, and an electrode active material having the above characteristics. Relates to a polymer.

  In recent years, portable electronic devices such as notebook computers and mobile phones are rapidly spreading with the development of communication systems, and their performance is also improving year by year. However, portable devices tend to increase power consumption as performance improves. Therefore, demands for high energy density, high output, etc. are increasing for the battery as the power source.

  As a high energy density battery, a lithium ion battery has been developed and widely used since the 1990s. This lithium ion battery uses, for example, a lithium-containing transition metal oxide such as lithium manganate or lithium cobaltate as the positive electrode and carbon as the negative electrode, and insertion and desorption reactions of lithium ions into these active materials. Charging and discharging is performed using Such a lithium ion battery has high energy density and excellent cycle characteristics, and is used in various electronic devices such as mobile phones. However, since the reaction rate of the electrode reaction is small, the battery performance is significantly lowered when a large current is taken out. For this reason, it is difficult to produce a large output, and there is a disadvantage that it takes a long time for charging.

  An electric double layer capacitor is known as an electricity storage device capable of producing a large output. Since a large current can be discharged at one time, it is possible to produce a large output, and it has excellent cycle characteristics, and is being developed as a backup power supply. However, since the energy density is very small and it is difficult to reduce the size, it is not suitable as a power source for portable electronic devices.

  In order to obtain an electrode material that is lightweight and has a large energy density, a battery using a sulfur compound or an organic compound as an active material has been developed. For example, Patent Document 1 (US Pat. No. 4,833,048) and Patent Document 2 (Japanese Patent No. 2715778) disclose batteries using an organic compound having a disulfide bond as a positive electrode. This is an electrochemical redox reaction involving generation and dissociation of disulfide bonds, which is used as a battery principle. Since this battery is composed of an electrode material mainly composed of an element having a small specific gravity such as sulfur or carbon, it has a certain effect in terms of a high-capacity battery having a high energy density. However, due to the low efficiency with which the dissociated bonds are recombined and the diffusion of the active material into the electrolyte, there are drawbacks in that the capacity tends to decrease with repeated charge / discharge cycles.

  In addition, as a battery using an organic compound, a battery using a conductive polymer as an electrode material has been proposed. This is a battery based on the principle of doping and dedoping of electrolyte ions 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 (US Pat. No. 4,442,187) discloses a battery using such a conductive polymer as a positive electrode or negative electrode material. This battery was composed only of elements having a small specific gravity such as carbon and nitrogen, and was expected as a high capacity 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. . This limits the generated charged radicals, that is, the doping concentration, and limits the capacity of the battery. For example, it has been reported that the doping rate of a battery using polyaniline as a positive electrode is 50% or less, and 7% in the case of polyacetylene. A battery using a conductive polymer as an electrode material has a certain effect in terms of weight reduction, but a battery having a large energy density has not been obtained.

As a battery using an organic compound as an active material of a secondary battery, a battery using a redox reaction of a radical compound has been proposed. For example, Patent Document 4 (Japanese Patent Laid-Open No. 2002-151084) discloses radical compounds such as a nitroxide radical compound, an aryloxy radical compound, and a polymer compound having a specific aminotriazine structure as active materials. A battery using a compound as a positive electrode or negative electrode material is disclosed.
US Pat. No. 4,833,048 Japanese Patent No. 2715778 U.S. Pat. No. 4,442,187 JP 2002-151084 A

  As described above, in a lithium ion battery using a transition metal oxide for the positive electrode, it is difficult to manufacture a battery having a high energy density per weight and a large output. The electric double layer capacitor has a large output, but the energy density is low. In addition, a battery using a sulfur compound or a conductive organic compound as an active material has not yet been obtained. A battery using an oxidation-reduction reaction of a radical compound may cause cracks in the electrode depending on the battery manufacturing method, and further improvement in energy density is desired.

  The present invention provides an electrode active material having a high capacity density and capable of extracting a large current, a battery having a high energy density and a large output, and an electrode active material having the above characteristics. The object is to provide a polymer which can be obtained.

  As a result of intensive studies by the present inventors, a specific organic compound that has not been used as an electrode active material until now, that is, a polymer (a) having in its molecule a unit represented by the following formula (1) It discovered that the said subject could be solved by utilizing as an active material. According to the present invention, a polymer (a) having a unit represented by the following formula (1) in the molecule is used as an electrode active material, and a novel battery using oxidation / reduction at this site is used. A novel battery capable of producing an energy density and a large output (specifically, a large current can be discharged) can be provided.

  That is, this invention is an electrode active material containing the polymer (a) which has a unit represented by following formula (1) in a molecule | numerator. Also, a novel battery comprising an electrode active material containing a polymer (a) having a unit represented by the following formula (1) in the molecule as at least one of the positive electrode and the negative electrode active material About.

In (Equation (1), X is a structure forming a main chain of the polymer, represents the following formula (2) or formula (3), R ¹ to R ³ is 1 to 3 carbon atoms each independently Represents an alkyl group.)

(In the formula (2), R ⁴ represents a hydrogen atom or a methyl group.)

(In Formula (3), R ⁴ represents a hydrogen atom or a methyl group, and R ⁵ represents an alkylene group having 1 to 3 carbon atoms.)

In the battery of the present invention, the polymer (a) undergoes an oxidation-reduction reaction as shown in the following scheme (I) or (II) during the charge / discharge process. In the oxidation-reduction reaction (I), when the polymer (a) is used for the positive electrode, the state is changed from (A) to (B) by charging, and electrons are released. The state changes from (B) to (A) by discharging, and receives electrons. Further, in the oxidation-reduction reaction (II), when the polymer (a) is used for the positive electrode, the state changes from (C) to (A) by charging, and electrons are released. The state changes from (A) to (C) by discharge, and receives electrons. From the stability of the redox reaction of the polymer (a), it is preferable to perform charge / discharge using the redox of scheme (I).

  In the battery, the electrode active material is oxidized or reduced by charge / discharge, and therefore the electrode active material takes two states, a starting state and a reduced state. In the present invention, the electrode active material becomes a polymer (a) in either a charged or discharged state.

  The present invention relates to a battery using an electrode reaction of an electrode active material, in which at least one of a positive electrode and a negative electrode reacts with a polymer (a) having in its molecule a structure represented by the above formula (1). Or it is related with the battery characterized by being an electrode reaction used as a product.

  The present invention also relates to any one of the above batteries, wherein the electrode active material is a positive electrode active material.

  The present invention also relates to any one of the above batteries, wherein the battery is a lithium battery.

  This invention is made | formed based on having discovered that said polymer (a) was excellent as an electrode active material. This is because the polymer (a) causes a reversible and stable oxidation-reduction reaction at a rate of almost 100% with little side reaction. That is, a battery using the polymer (a) as an electrode active material can be stably charged and discharged, and has excellent cycle characteristics. A battery using the polymer (a) as an electrode active material has excellent high output characteristics as compared with a conventional lithium ion battery. This is because a large current can be discharged at a time because the structure represented by the formula (1) of the polymer (a) has a large electrode reaction rate. Moreover, a polymer (a) can be comprised only from elements with small mass called carbon, nitrogen, hydrogen, and oxygen. For this reason, the mass of the electrode active material can be reduced, and the capacity density per unit mass of an electrode manufactured using the same can be increased. As a result, when a battery is produced using this electrode active material, the energy density per mass is Becomes a big battery.

  Moreover, in this invention, the polymer (a) should just contribute directly to the electrode reaction in a positive electrode or a negative electrode, and the electrode used as an electrode active material is not limited to either a positive electrode or a negative electrode. . However, from the viewpoint of energy density, it is particularly preferable to use this polymer (a) as an electrode active material for the positive electrode. In addition, the battery of the present invention is preferably a lithium battery using carbon capable of inserting and removing metallic lithium or lithium ions in the negative electrode from the viewpoint that a high voltage and a large capacity can be obtained.

  The present invention also provides a novel polyradical compound having a unit represented by the formula (11) in the molecule.

(In formula (11), Z is a structure forming the main chain of the polymer, and represents the following formula (12) or formula (13), and R ^{1 ′} represents a hydrogen atom or a methyl group.)

(In Formula (12), R ^{4 ′} represents a hydrogen atom or a methyl group.)

(In Formula (13), R ^{4 ′} represents a hydrogen atom or a methyl group.)

  The present invention proposes an electrode active material containing a polymer (a) having a unit represented by the formula (1) in the molecule, and a new battery using this electrode active material. This makes it possible to produce a battery composed of light and safe elements that do not contain heavy metals as an electrode active material, and has high capacity (per mass) and excellent charge / discharge cycle stability. In addition, a battery capable of producing a larger output can be realized.

FIG. 1 shows the configuration of one embodiment of the battery of the present invention. In the battery shown in FIG. 1, the positive electrode 6 and the negative electrode 4 arranged on the negative electrode current collector 3 are stacked so as to face each other with a separator 5 containing an electrolyte, and a positive electrode current collector 7 is placed on the positive electrode 6. It has a superposed configuration. These are packaged by an aluminum exterior 1 on the negative electrode side and an aluminum exterior 1 on the positive electrode side, and an insulating packing 2 made of an insulating material such as a plastic resin is disposed between them for the purpose of preventing electrical contact therebetween. . In addition, when using solid electrolyte and gel electrolyte as electrolyte, it can replace with a separator and can also be made into the form which interposes these electrolytes between electrodes.
In the present invention, the present invention is characterized in that the electrode active material used for the negative electrode 4 or the positive electrode 6 or both electrodes is an electrode active material containing the polymer (a) described later.

  The battery of the present invention is preferably a lithium battery using the above electrode active material as a positive electrode active material from the viewpoint of battery capacity.

[1] Electrode active material The electrode active material of the electrode in the present invention is a material that directly contributes to electrode reactions such as charge reaction and discharge reaction, and plays a central role in the battery system.

  In this invention, the electrode active material containing the polymer (a) which has a unit represented by following formula (1) in a molecule | numerator can be used as an electrode active material.

In the formula (1), X is a structure forming the main chain of the polymer, and represents any one of the following formulas (2) to (5), and R ^{1 to} R ³ are each independently a methyl group, ethyl Represents any of a group, an n-propyl group, and an isopropyl group. From the viewpoint of ease of synthesis, R ^{1 to} R ³ are preferably methyl groups.

In the formula (2), R ⁴ represents a hydrogen atom or a methyl group.

In the formula (3), R ⁴ is a hydrogen atom or a methyl group, R ⁵ is a methylene group, an ethylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group. Propane-1,3-diyl group and propane-2,2-diyl group. From the viewpoint of ease of synthesis, R ⁵ is preferably a methylene group.

In the formula (4), R ^{6 to} R ⁸ each independently represents a hydrogen atom or a methyl group.

In the formula (5), R ^{6 to} R ⁸ are each independently a hydrogen atom or a methyl group, R ⁹ is a methylene group, ethylene group, ethane-1,1-diyl group, propane-1,1-diyl group, propane It represents any of a -1,2-diyl group, a propane-1,3-diyl group, and a propane-2,2-diyl group. From the viewpoint of ease of synthesis, R ⁹ is preferably a methylene group.

  In the battery of the present invention, the electrode active material may be fixed to the electrode, or may be dissolved or dispersed in the electrolyte. However, when used in a state of being fixed to the electrode, in order to suppress a decrease in capacity due to dissolution in the electrolytic solution, it is preferably insoluble or low-soluble in the electrolytic solution in the solid state. This is because, when the solubility in the electrolytic solution is high, the electrode active material is eluted from the electrode into the electrolytic solution, so that the capacity decreases with the charge / discharge cycle. Therefore, the polymer (a) preferably has a number average molecular weight of 500 or more, and more preferably a number average molecular weight of 5000 or more. This is because when the number average molecular weight is 500 or more, it is difficult to dissolve in the battery electrolyte, and when the number average molecular weight is 5000 or more, it is almost insoluble. The polymer may be in the form of a chain, a branch, or a network. The upper limit of the number average molecular weight is not particularly limited, but a polymer compound having a number average molecular weight of 5000000 or less, more preferably a number average molecular weight of 1000000 or less can be suitably used for the convenience of synthesis. Moreover, the structure which bridge | crosslinked with the crosslinking agent may be sufficient.

  As said polymer, the homopolymer which has only the unit represented by Formula (1) can be used, and the copolymer which has another unit can also be used. For the convenience of synthesis, a homopolymer is preferred. In the case of a copolymer, the unit represented by the formula (1) is preferably 70 to 99 unit%, and more preferably 80 to 95 unit%, based on all units of the polymer compound.

  Examples of the polymer (a) include polymers having units represented by the following formulas (14) to (21).

  The polymer having a unit represented by the above formula (14) can be synthesized, for example, by the route shown in the following synthesis scheme. Methyl vinyl ketone is Michael-added to 2-nitropropane using tetramethyl anidine as a catalyst to give 5-nitro-2-hexanone. The obtained 5-nitro-2-hexanone is cyclized in water with ammonium chloride and zinc to form a cyclic nitrone compound. The obtained nitrone compound is introduced with an ethynyl group by Grignard reaction using ethynylmagnesium bromide in ether and further converted into a nitroxide radical by air oxidation using a copper catalyst. By polymerizing this with a rhodium catalyst, a polymer having a unit represented by the formula (14) is obtained.

  The polymer that can be used as the polymer (a) can also be synthesized by a method similar to the above synthesis method. That is, after introducing an ethynyl group and a vinyl group into a cyclic nitrone compound by a Grignard reaction, a polymerizable monomer having a nitroxide radical is obtained by an oxidation reaction. This is polymerized with a suitable polymerization catalyst. In the case of an ethynyl group, it can be polymerized not only by a rhodium catalyst but also by a catalyst in which molybdenum, tungsten, niobium, tantalum chloride and an alkyltin compound, an alkylaluminum compound or the like are combined. In the case of a vinyl group, it can be polymerized by a catalyst in which a transition metal compound such as titanium tetrachloride, titanium trichloride, vanadium tetrachloride, or vanadium trichloride is combined with an organometallic compound of a typical metal such as triethylaluminum. The target polymer can be synthesized by appropriately changing the synthesis scheme, raw materials to be used, reaction conditions and the like, and combining known synthesis techniques.

  In the electrode active material of one electrode of the battery of the present invention, the polymer (a) can be used alone, but two or more kinds may be used in combination. Moreover, you may use in combination with another electrode active material. At this time, it is preferable that 10-90 mass% of polymers (a) are contained in an electrode active material, and it is more preferable that 20-80 mass% is contained.

When the polymer (a) is used for the positive electrode, a metal oxide, a disulfide compound, another stable radical compound, a conductive polymer, and the like can be combined as another electrode active material. Here, as the metal oxide, for example, lithium manganate such as LiMnO ₂ , Li _x Mn ₂ O ₄ (0 <x <2) or lithium manganate having a spinel structure, MnO ₂ , LiCoO ₂ , LiNiO ₂ , Alternatively, Li _X V ₂ O ₅ (0 <x <2) or the like may be used as disulfide compounds such as dithioglycol, 2,5-dimercapto-1,3,4-thiadiazole, S-triazine-2,4,6-trithiol. Other stable radical compounds include poly (2,2,6,6-tetramethylpiperidinoxyl-4-yl methacrylate) and the like, and conductive polymers include polyacetylene, polyphenylene, polyaniline, and polypyrrole. Etc. In particular, it is preferable to combine with lithium manganate or LiCoO ₂ . In the present invention, these other electrode active materials can be used alone or in combination of two or more.

  When the polymer (a) is used for the negative electrode, graphite, amorphous carbon, metallic lithium or lithium alloy, lithium ion storage carbon, metallic sodium, conductive polymer, or the like can be used as another electrode active material. Moreover, you may use another stable radical compound. Other stable radical compounds include poly (2,2,6,6-tetramethylpiperidinoxyl-4-yl methacrylate). These shapes are not particularly limited. For example, metallic lithium is not limited to a thin film shape, and may be a bulk shape, a powdered shape, a fiber shape, a flake shape, or the like. These other electrode active materials can be used alone or in combination of two or more.

The battery of the present invention uses the polymer (a) as an electrode active material in one electrode reaction of the positive electrode or the negative electrode, or both electrode reactions. As the electrode active material in the electrode, conventionally known electrode active materials such as those exemplified above can be used. These electrode active materials can be used alone or in combination of two or more thereof, and at least one of these electrode active materials and the polymer (a) may be used in combination. Moreover, a polymer (a) can also be used independently.
[2] Conductivity-imparting agent (auxiliary conductive material) and ion-conducting auxiliary material When the electrode is formed using the polymer (a), conductivity is imparted for the purpose of reducing impedance and improving energy density and output characteristics. An agent (auxiliary conductive material) or an ion conduction auxiliary material can also be mixed. As these materials, as auxiliary conductive materials, carbonaceous fine particles such as graphite, carbon black and acetylene black, carbon fibers such as vapor-grown carbon fibers and carbon nanotubes, conductive materials such as polyaniline, polypyrrole, polythiophene, polyacetylene and polyacene are used. A polymer gel electrolyte, a polymer solid electrolyte, and the like. As a ratio of these materials in an electrode, 10-80 mass% is preferable.

[3] Binder A binder can also be used to strengthen the connection between the constituent materials of the electrode. Examples of such binders include polytetrafluoroethylene, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, styrene / butadiene copolymer rubber, polypropylene, and polyethylene. Resin binders such as polyimide and various polyurethanes. As a ratio of these materials in an electrode, 5-30 mass% is preferable.

[4] Catalyst In order to perform the electrode reaction more smoothly, a catalyst that assists the redox reaction can be used. Examples of such catalysts include conductive polymers such as polyaniline, polypyrrole, polythiophene, polyacetylene, and polyacene, basic compounds such as pyridine derivatives, pyrrolidone derivatives, benzimidazole derivatives, benzothiazole derivatives, and acridine derivatives, metal ion complexes, and the like. Can be mentioned. The ratio of these materials in the electrode is preferably 10% by mass or less.

[5] Current collector and separator As the negative electrode current collector and the positive electrode current collector, foils made of nickel, aluminum, copper, gold, silver, aluminum alloy, stainless steel, carbon, etc., metal flat plates, mesh shapes, etc. Things can be used. Further, the current collector may have a catalytic effect, or the electrode active material and the current collector may be chemically bonded. On the other hand, a separator such as a porous film or non-woven fabric made of polyethylene, polypropylene, or the like can be used so that the positive electrode and the negative electrode are not in contact with each other.

[6] Electrolyte In the present invention, the electrolyte performs charge carrier transport between the negative electrode and the positive electrode, and generally has an ionic conductivity of 10 ⁻⁵ to 10 ⁻¹ S / cm at 20 ° C. Preferably it is. As the electrolyte, for example, an electrolytic solution in which an electrolyte salt is dissolved in a solvent can be used. Examples of the electrolyte salt include LiPF ₆ , LiClO ₄ , LiBF ₄ , LiCF ₃ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N, Li (C ₂ F ₅ SO ₂ ) ₂ N, Li (CF ₃ SO ₂ ) ₃ C Conventionally known materials such as Li (C ₂ F ₅ SO ₂ ) ₃ C can be used.

  When a solvent is used for the electrolytic solution, examples of the solvent include ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, γ-butyrolactone, tetrahydrofuran, dioxolane, sulfolane, dimethylformamide, dimethylacetamide, N-methyl- An organic solvent such as 2-pyrrolidone can be used. These solvents can be used alone or in admixture of two or more.

  Furthermore, in the present invention, a solid electrolyte can be used as the electrolyte. Polymer compounds used in these solid electrolytes include polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-ethylene copolymer, vinylidene fluoride-monofluoroethylene copolymer, vinylidene fluoride. -Vinylidene fluoride polymers such as trifluoroethylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, and acrylonitrile-methyl methacrylate copolymer Polymer, acrylonitrile-methyl acrylate copolymer, acrylonitrile-ethyl methacrylate copolymer, acrylonitrile-ethyl acrylate copolymer, acrylonitrile-methacrylic acid copolymer, acrylonitrile-acrylic Le acid copolymers, acrylonitrile - vinyl acetate copolymer, acrylonitrile-based polymer, further polyethylene oxide, ethylene oxide - propylene oxide copolymers, and polymers of these acrylates body or methacrylate body thereof. These polymer compounds may be used in the form of a gel containing an electrolytic solution, or only a polymer compound containing an electrolyte salt may be used as it is.

[7] Battery shape In the present invention, the shape of the battery is not particularly limited, and a conventionally known battery can be used. Examples of the battery shape 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 coin mold, and a sheet mold are used, but the present invention is not limited to these.

[8] Battery Manufacturing Method The battery manufacturing method 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 and diethyl ether, amine solvents such as N-methylpyrrolidone, aromatic hydrocarbon solvents such as benzene, toluene and xylene, and aliphatic solvents such as hexane and heptane. Examples thereof include hydrocarbon solvents and halogenated hydrocarbon solvents such as chloroform and dichloromethane. 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, especially 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, cracking occurs in the electrode. Cheap. When the polymer (a) of the present invention is used, and an electrode having a thickness of preferably 80 μm or more and 500 μm or less is produced, the electrode is also resistant to cracking, and a uniform electrode can be produced. .

When manufacturing a battery, a battery is manufactured using the polymer (a) itself as an electrode active material, and a battery is manufactured using a polymer that changes to the polymer (a) by an electrode reaction. There is. Examples of the polymer that changes to the polymer (a) by such an electrode reaction include a lithium salt or a sodium salt comprising an anion obtained by reducing the polymer (a) and an electrolyte cation such as lithium ion or sodium ion. , Alternatively, the polymer (a) cation body and PF ₆ was oxidized ^- or BF ₄ ^-, salts consisting of such electrolyte anions.

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

  Hereinafter, although the detail of this invention is concretely demonstrated by a synthesis example and an Example, this invention is not limited to these Examples.

(Synthesis Example 1)
The polymer (14) (a homopolymer having a unit represented by the following formula (14)) was synthesized from 2-nitropropane by a four-step reaction.

  [1] Synthesis of 2-methyl-2-nitro-5-hexanone

  In a 500 ml eggplant flask, 35.7 g (509 mmol) of methyl vinyl ketone was dissolved in 130 ml (3.95 M) of acetonitrile. 2-Nitropropane (50.0 g, 560 mmol, 1.1 eq) was added, and tetramethylguanidine (TMG) (5.86 g, 50.9 mmol, 0.1 eq) was added dropwise in an ice bath, followed by reaction at room temperature for 24 hours. It was. After completion of the reaction, the reaction solution was poured into 500 ml of water containing 30 ml of hydrochloric acid, and extracted with ether and washed with water. After drying with sodium sulfate, 28.2 g of colorless liquid 2-methyl-2-nitro-5-hexanone was obtained through solvent removal and reduced pressure distillation (bp 76 ° C., 5 mmHg). (Yield 32%).

¹ H-NMR (CDCl ₃ , 500 MHz, ppm): δ = 2.45 (t, 2H, CH ₂ ), 2.19 (t, 2H, CH ₂ ), 2.16 (s, 3H, CH ₃ ) , 1.58 (s, 6H, CH ₃ )
¹³ C-NMR (CDCl ₃ , 125 MHz, ppm): δ = 206.3, 87.3, 38.1, 33.9, 29.9, 25.8
IR (cm ⁻¹ ): 1719 (ν _C═O ) 1348 (ν _CN )
Elemental analysis: measured value C, 52.6; H, 8.4; N, 8.7%, calculated value (C ₇ H ₁₃ NO ₃ ) C, 52.8; H, 8.2; N, 8. 8%
[2] Synthesis of cyclic nitrones

  In a 200 ml eggplant flask, 5.1 g (31.4 mmol) of 2-methyl-2-nitro-5-hexanone and an ammonium chloride aqueous solution (1.7 g (31.4 mmol, 1.0 eq) of ammonium chloride dissolved in 42 ml of water ) And cooled to 0 ° C. 8.3 g (126 mmol, 4.0 eq) of zinc powder was added, and the mixture was stirred at 0 ° C. for 1 hour. Furthermore, it was made to react at room temperature for 2 hours. After completion of the reaction, it is filtered and washed with methanol. After removing the solvent, the mixture was extracted with chloroform and washed with a saturated aqueous sodium sulfate solution. After drying and solvent removal, benzene was added to remove water and the like azeotropically. Through a silica gel column purification using chloroform as a developing solvent, 3.54 g of a light yellow liquid was obtained as a cyclic nitrone (yield 88.5%).

¹ H-NMR (CDCl ₃ , 500 MHz, ppm): δ = 2.59 (t, 2H, CH ₂ ), 2.03 (s, 3H, CH ₃ ), 2.00 (t, 2H, CH ₂ ) , 1.40 (s, 6H, CH ₃ )
¹³ C-NMR (CDCl ₃ , 125 MHz, ppm): δ = 141.9, 100.5, 73.1, 32.2, 29.1, 25.3, 13.0
IR (cm ⁻¹ ): 1627 (ν _{C = N} )
Mass: m / z 127 (found), 127.18 (calcd)
[3] Synthesis of 2-ethynyl proxy radical

Under an argon atmosphere, 72 ml (36.0 mmol, 1.5 eq) of ethynylmagnesium bromide 0.5 M THF solution was added to a 500 ml three-necked eggplant flask. 3.07 g (24.0 mmol) of the cyclic nitrone is dissolved in 30 ml of THF and then added dropwise to the Grignard reagent. After reaction at room temperature for 2 hours, a saturated aqueous ammonium chloride solution was added. The organic layer was washed with saturated brine, the solvent was removed, and oxidation was performed immediately. To the product, 47.9 ml of methanol, 1.2 ml of t-butylammonium and 120 mg of copper acetate were added and reacted under oxygen for 18 hours. After completion of the reaction, the mixture was extracted with chloroform and washed with an aqueous sodium hydrogen carbonate solution. The column was purified using diethyl ether as a developing solvent (Rf = 0.4) to obtain 1.36 g of 2-ethynyl proxy radical as orange crystals. (Yield 37%)
^{IR (cm -1): 3243 (} ν≡ CH), 2106 (ν C ≡ C)
Elemental analysis: measured value: C, 71.2; H, 9.2; N, 8.9%, calculated value (C ₉ H ₁₄ NO): C, 71.0; H, 9.3; N, 9 .2%.
[4] Polymerization of 2-ethynyl proxy radical

100 mg of 2-ethynylproxyl radical was added to a 30 ml 2-neck eggplant flask and dissolved in 6.6 ml (0.1 M) of TEA. Under an argon atmosphere, Rh catalyst [Rh (nbd) Cl] ₂ , 15.2 mg (0.033 mmol, 0.05 eq) was added and reacted at room temperature for 3 days. After completion of the reaction, it was purified by reprecipitation in methanol, hexane, ether, etc., but did not precipitate, but purified by preparative high performance liquid chromatography to obtain a polymer (14) as a dark red solid. (Number average molecular weight 1000 (polystyrene conversion), dispersity (weight average molecular weight / number average molecular weight 1.1)
Example 1
Polymer (14) synthesized in Synthesis Example 1 (number average molecular weight 1000 (polystyrene conversion), dispersity (weight average molecular weight / number average molecular weight) 1.1) 300 mg, carbon powder 600 mg, polytetrafluoroethylene resin binder 100 mg Weighed and kneaded using an agate mortar. The mixture obtained by dry-mixing for about 10 minutes was subjected to roller stretching under pressure to obtain a thin film having a thickness of about 150 μm. This was dried overnight at 80 ° C. in a vacuum, and then punched into a circle with a diameter of 12 mm to form a coin battery electrode. The mass of this electrode was 14.6 mg.

Next, the obtained electrode was immersed in an electrolytic solution, and the electrolytic solution was infiltrated into voids in the electrode. As the electrolytic solution, an ethylene carbonate / diethyl carbonate mixed solution (mixing volume ratio 3: 7) containing 1.0 mol / L LiPF ₆ electrolyte salt was used. The electrode impregnated with the electrolytic solution was placed on the positive electrode current collector, and a polypropylene porous film separator impregnated with the electrolytic solution was laminated thereon. Further, a lithium-bonded copper foil serving as a negative electrode was laminated, and aluminum sheaths (made by Hohsen) were superposed from the positive electrode side and the negative electrode side in a state in which an insulating packing was disposed around. This was applied with a caulking machine to form a sealed coin-type battery using the polymer (14) as the positive electrode active material and metal lithium as the negative electrode active material.

  The coin battery fabricated as described above was charged with a constant current of 0.1 mA until the voltage reached 4.0 V, and then discharged to 3.0 V with a constant current of 0.1 mA. As a result, the voltage became almost constant for 5 hours near 3.5 V, and then dropped rapidly. The discharge capacity per electrode active material was 141.3 mAh / g. Similarly, charging / discharging was repeated 50 times in the range of 4.2 to 2.8V. As a result, in all 50 charge / discharge cycles, the voltage became constant at around 3.5 V during discharge, and (50th discharge capacity) / (1st discharge capacity) was 97.0%.

  Next, the coin battery was charged with a constant current of 0.1 mA until the voltage reached 4.2 V, and then discharged with a constant current of 5.0 mA. As a result, the voltage became constant around 3.4 V and then dropped rapidly. (Discharge capacity at 5.0 mA discharge) / (discharge capacity at 0.1 mA discharge) was 96.3%.

(Example 2)
Weighed 20 g of N-methylpyrrolidone into a small homogenizer container, added 400 mg of polyvinylidene fluoride, and stirred for 30 minutes to completely dissolve. Thereto, 1.0 g of the polymer (14) synthesized in Synthesis Example 1 was added and stirred for 5 minutes until the whole became a uniform orange color. Here, 600 mg of carbon powder was added, and further stirred for 15 minutes to obtain a slurry. The obtained slurry was applied on an aluminum foil and dried at 125 ° C. to produce a positive electrode. The thickness of the positive electrode layer was 120 μm. The produced electrode was not cracked and the surface was uniform. This was punched out into a circle with a diameter of 12 mm to mold a coin battery electrode. Next, the obtained electrode was immersed in an electrolytic solution, and the electrolytic solution was infiltrated into voids in the electrode. As the electrolytic solution, an ethylene carbonate / diethyl carbonate mixed solution (mixing volume ratio 3: 7) containing 1.0 mol / L LiPF ₆ electrolyte salt was used. The electrode impregnated with the electrolytic solution was placed on a positive electrode current collector (aluminum foil), and a polypropylene porous film separator impregnated with the electrolytic solution was laminated thereon. Further, a copper foil having a graphite layer on one side as a negative electrode was laminated, and the respective aluminum sheaths (made by Hohsen) were superposed from the positive electrode side and the negative electrode side in a state where an insulating packing was disposed around the copper foil. This was applied with a caulking machine to obtain a sealed coin-type battery using the polymer (14) as the positive electrode active material and graphite as the negative electrode active material.

  The coin battery fabricated as described above was charged with a constant current of 0.1 mA until the voltage reached 4.0 V, and then discharged to 3.0 V with a constant current of 0.1 mA. As a result, the voltage became substantially constant for 2.0 hours near 3.5 V, and then dropped rapidly. The discharge capacity per electrode active material was 132.4 mAh / g. Similarly, charging / discharging was repeated 50 times in the range of 4.2 to 2.8V. As a result, in all 50 charge / discharge cycles, the voltage became constant at around 3.5 V during discharge, and (50th discharge capacity) / (1st discharge capacity) was 97.0%.

  Next, the coin battery was charged with a constant current of 0.1 mA until the voltage reached 4.2 V, and then discharged with a constant current of 5.0 mA. As a result, the voltage became constant around 3.4 V and then dropped rapidly. (Discharge capacity at 5.0 mA discharge) / (discharge capacity at 0.1 mA discharge) was 88.0%.

(Example 3)
Polymer (15) (homopolymer having a unit represented by the following formula (15), number average molecular weight 6900 (in terms of polystyrene), dispersity (weight average molecular weight / number average) by the same synthesis scheme as in Synthesis Example 1 The molecular weight was 1.64), and a coin battery was produced in the same manner as in Example 1 using the polymer (15) obtained. The positive electrode weight of this coin battery was 11.52 mg.

  The coin battery was charged with a constant current of 0.1 mA until the voltage reached 4.0 V, and then discharged to 3.0 V with a constant current of 0.1 mA. As a result, a flat voltage portion was observed at around 3.5 V for 4 hours. The discharge capacity per electrode active material was 121.34 mAh / g. As a result of repeating charging and discharging 50 times in the range of 4.0 to 3.0 V, (50th discharge capacity) / (1st discharge capacity) was 97.0%.

  Next, the coin battery was charged with a constant current of 0.1 mA until the voltage reached 4.0 V, and then discharged with a constant current of 5.0 mA. (Discharge capacity at 5.0 mA discharge) / (discharge capacity at 0.1 mA discharge) was 94.8%.

Example 4
Polymer (16) (homopolymer having a unit represented by the following formula (16), number average molecular weight 1300 (polystyrene conversion), dispersity (weight average molecular weight / number average) by the same synthesis scheme as in Synthesis Example 1 The molecular weight was 1.23), and a coin battery was produced in the same manner as in Example 1 using the obtained polymer (16). The positive electrode weight of this coin battery was 10.57 mg.

  The coin battery was charged with a constant current of 0.1 mA until the voltage reached 4.0 V, and then discharged to 3.0 V with a constant current of 0.1 mA. As a result, a flat voltage portion was observed at around 3.5 V for 4 hours. The discharge capacity per electrode active material was 131.33 mAh / g. As a result of repeating charging and discharging 50 times in the range of 4.0 to 3.0 V, (50th discharge capacity) / (1st discharge capacity) was 88.9%.

  Next, the coin battery was charged with a constant current of 0.1 mA until the voltage reached 4.0 V, and then discharged with a constant current of 5.0 mA. As a result, (discharge capacity at 5.0 mA discharge) / (discharge capacity at 0.1 mA discharge) was 84.8%.

(Example 5)
Polymer (17) (homopolymer having a unit represented by the following formula (17), number average molecular weight: 8600 (polystyrene conversion), dispersity (weight average molecular weight / number average) by the same synthesis scheme as in Synthesis Example 1. The molecular weight was 1.44), and a coin battery was produced in the same manner as in Example 1 using the polymer (17) obtained. The positive electrode weight of this coin battery was 13.3 mg.

  The coin battery was charged with a constant current of 0.1 mA until the voltage reached 4.0 V, and then discharged to 3.0 V with a constant current of 0.1 mA. As a result, a flat voltage portion was observed at around 3.5 V for 4 hours. The discharge capacity was 106.24 mAh / g. As a result of repeating charging and discharging 50 times in the range of 4.0 to 3.0 V, (50th discharge capacity) / (1st discharge capacity) was 92.2%.

  Next, the coin battery was charged with a constant current of 0.1 mA until the voltage reached 4.0 V, and then discharged with a constant current of 5.0 mA. (Discharge capacity at 5.0 mA discharge) / (discharge capacity at 0.1 mA discharge) was 89.8%.

(Comparative Example 1)
A coin battery was manufactured in the same manner as in Example 1, except that the polymer (14) was not used and the graphite powder was increased to 900 mg instead. The produced battery was charged and discharged in the same manner as in Example 1. As a result, no flat voltage portion was observed during discharge, the voltage dropped rapidly, and the battery did not operate sufficiently.

(Comparative Example 2)
A coin battery was manufactured in the same manner as in Example 1, except that the polymer (14) was not used and 300 mg of LiCoO ₂ was used instead. The produced battery was charged and discharged in the same manner as in Example 1, and the discharge capacity per electrode active material was calculated to be 96 mAh / g. (Discharge capacity at 5.0 mA discharge) / (discharge capacity at 0.1 mA discharge) was 26.8%.

(Comparative Example 3)
A coin battery was prepared in the same manner as in Example 1, except that the polymer (14) was not used and 300 mg of 2,2,6,6-tetramethylpiperidinoxyl (TEMPO) was used instead. The discharge capacity per electrode active material was 35.2 mAh / g. As a result of repeating charging / discharging 12 times in the range of 4.0-3.0V, charging / discharging became impossible and it did not operate | move as a battery.

(Comparative Example 4)
In the same manner as in Example 2, but without using the polymer (14), instead of poly (2,2,6,6-tetramethylpiperidinoxyl-4-yl methacrylate) (number average molecular weight 12700 An electrode was prepared using 1.0 g (polystyrene conversion) and dispersity (weight average molecular weight / number average molecular weight 3.0). The thickness of the produced positive electrode layer was 130 μm. Many fine cracks were observed on the electrode surface. When charge / discharge was performed in the same manner as in Example 2 and the discharge capacity per electrode active material was calculated, the discharge capacity per electrode active material was 56.9 mAh / g. (Discharge capacity at 5.0 mA discharge) / (discharge capacity at 0.1 mA discharge) was 48%.

It is a conceptual diagram which shows an example of a structure of the battery of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Aluminum exterior 2 Insulation packing 3 Negative electrode collector 4 Negative electrode 5 Separator 6 Positive electrode 7 Positive electrode collector

Claims (6)

The electrode active material containing the polymer (a) which has a unit represented by following formula (1) in a molecule | numerator.

In (Equation (1), X is a structure forming a main chain of the polymer, represents the following formula (2) or formula (3), R ¹ to R ³ is 1 to 3 carbon atoms each independently Represents an alkyl group.)

(In the formula (2), R ⁴ represents a hydrogen atom or a methyl group.)

(In Formula (3), R ⁴ represents a hydrogen atom or a methyl group, and R ⁵ represents an alkylene group having 1 to 3 carbon atoms.)   A battery comprising the electrode active material according to claim 1 as an electrode active material of at least one of a positive electrode and a negative electrode. In a battery utilizing an electrode reaction of an electrode active material, at least one of the positive electrode and the negative electrode reacts with a reaction product or a polymer (a) having a unit represented by the following formula (1) in the molecule. A battery characterized by an electrode reaction.

In (Equation (1), X is a structure forming a main chain of the polymer, represents the following formula (2) or formula (3), R ¹ to R ³ is 1 to 3 carbon atoms each independently Represents an alkyl group.)

(In the formula (2), R ⁴ represents a hydrogen atom or a methyl group.)

(In Formula (3), R ⁴ represents a hydrogen atom or a methyl group, and R ⁵ represents an alkylene group having 1 to 3 carbon atoms.)   The battery according to claim 2, wherein the electrode active material is a positive electrode active material.   The battery according to any one of claims 2 to 4, which is a lithium secondary battery. The polyradical compound which has a unit represented by following formula (11) in a molecule | numerator.

(In formula (11), Z is a structure forming the main chain of the polymer, and represents the following formula (12) or formula (13), and R ^{1 ′} represents a hydrogen atom or a methyl group.)

(In Formula (12), R ^{4 ′} represents a hydrogen atom or a methyl group.)

(In Formula (13), R ^{4 ′} represents a hydrogen atom or a methyl group.)

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