JP4830207B2 - battery - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a battery including at least a positive electrode, a negative electrode, and an electrolyte as constituent elements. More specifically, a battery having particles including, as active materials, an organic compound that includes at least a positive electrode, a negative electrode, and an electrolyte, and generates a radical compound in at least one of an electrochemical oxidation reaction and a reduction reaction. The present invention relates to a secondary battery in which the particles are a composite composed of at least two composition regions, have a high energy density, a large capacity, and excellent stability.
[0002]
[Prior art]
Batteries are obtained by converting chemical energy into electrical energy using the oxidation-reduction reaction that occurs at the positive electrode and negative electrode, or converting electrical energy into chemical energy for storage. It is used as.
In recent years, with the rapid market expansion of notebook personal computers, mobile phones and the like, there is an increasing demand for small high-capacity batteries with high energy density used for these. In order to meet this demand, a secondary battery using an alkali metal ion such as lithium ion as a charge carrier and utilizing an electrochemical reaction accompanying the charge transfer has been developed. Among these, lithium ion secondary batteries are used in various electronic devices as high-capacity batteries having excellent stability and high energy density.
[0003]
In such a lithium ion secondary battery, for example, a lithium-containing transition metal oxide is used as a positive electrode as an active material, and a carbon material is used as a negative electrode, and the insertion reaction and desorption reaction of lithium ions with respect to these active materials are utilized. Charging and discharging.
[0004]
However, since this lithium ion secondary battery uses a transition metal oxide having a large specific gravity as the positive electrode active material, there is a problem that the battery capacity per unit mass is not sufficient. That is, it is difficult in principle to manufacture a large capacity battery.
[0005]
Thus, attempts have been made to develop large-capacity batteries using lighter electrode materials. For example, US Pat. Nos. 4,833,048 and 2715778 disclose batteries using an organic compound having a disulfide bond as an active material for a positive electrode. This utilizes the electrochemical redox reaction of organic compounds based on the formation and dissociation of disulfide bonds as the principle of the battery.
[0006]
However, since this battery uses an organic compound mainly composed of an element having a small specific gravity such as sulfur or carbon as an electrode material, it has a certain effect in that it constitutes a high-capacity battery having a high energy density. There is a problem that the recombination efficiency of the dissociated disulfide bond is small and the stability in the charged state or the discharged state is insufficient.
Furthermore, since an organic compound having a disulfide bond does not have electronic conductivity, it has been necessary to use it in combination with other conductive materials such as polyaniline and conductive carbon.
[0007]
Similarly, a battery using a conductive polymer as an electrode material has been proposed as a battery using an organic compound as an active material. This is a battery based on the principle of doping and dedoping reactions of electrolyte ions on conductive polymers.
The dope reaction described here is defined as a reaction that stabilizes excitons such as charged solitons and polarons generated by a reaction of electrochemically oxidizing or reducing a conductive polymer with a counter ion. On the other hand, the dedoping reaction is defined as a reverse reaction of the doping reaction, that is, a reaction in which exciton stabilized by a counter ion is electrochemically oxidized or reduced.
[0008]
US Pat. No. 4,442,187 discloses a battery using such a conductive polymer as a positive or negative active material. This battery is expected to be developed as a large-capacity battery because an organic compound composed only of an element having a small specific gravity such as carbon or nitrogen is used as an electrode material.
[0009]
However, conductive polymers have the property that excitons generated by electrochemical redox reactions are delocalized over a wide range of π-electron conjugated systems and interact with each other. Since the concentration is also limited, there is a problem that the capacity of the battery is limited.
[0010]
Therefore, in a battery using such a conductive polymer as an electrode material, a certain effect can be obtained in terms of reducing the weight of the battery, but it is still insufficient in terms of increasing the capacity of the battery.
[0011]
On the other hand, methods for synthesizing organic compounds such as polymer compounds using radical reactions have been developed and used for developing various materials.
However, radical reactions are generally more reactive than other chemical reactions and are difficult to control, so that application to energy storage devices such as batteries has not been studied in detail.
[0012]
Here, the radical reaction is a chemical reaction involving a radical. In particular, in the present invention, an organic compound which is a non-radical compound is a radical compound in at least one of an electrochemical oxidation reaction and a reduction reaction. And a reaction in which the generated radical compound is converted to a non-radical compound.
[0013]
As described above, various types of batteries have been proposed in order to realize a large-capacity battery, but a battery having a high energy density, a large capacity and excellent stability has not yet been established.
In addition, studies on applying the above radical reaction to energy storage devices such as batteries have not been actively carried out because radical compounds are unstable.
[0014]
[Problems to be solved by the invention]
Thus, as a result of intensive studies, the present inventors have determined that particles containing an organic compound that generates a radical compound by the radical reaction in at least one of an electrochemical oxidation reaction and a reduction reaction that are charge / discharge reactions of the battery, It was found that the particles can be used as an active material for an energy storage device such as a battery by forming a composite composed of at least two regions having a composition.
[0015]
Therefore, in the present invention, a particle containing an organic compound that generates such a radical compound as an active material is made into a composite composed of at least two regions of composition, so that the energy density is high, the capacity is high, and the stability is high. The purpose is to provide an excellent battery.
[0016]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, at least a positive electrode, a negative electrode, and an electrolyte are used as constituent elements, and an organic compound that generates a radical compound in at least one of an electrochemical oxidation reaction and a reduction reaction is used as an active material. There is provided a battery having a particle including the battery, wherein the particle is a composite composed of at least two regions having a composition.
[0017]
By comprising in this way, since a radical compound can be comprised only from elements with small specific gravity like carbon, hydrogen, nitrogen, oxygen, etc., the energy density per unit mass is high, and it was excellent in stability with a large capacity. A battery can be obtained easily.
[0018]
In addition, when the above particles are a composite composed of at least two regions of composition, the decay of organic compounds that generate radical compounds in at least one of the electrochemical oxidation reaction and the reduction reaction and the dissolution in the electrolyte are suppressed. As a result, by performing the oxidation-reduction reaction in a state where the organic compound that generates the radical compound is stable, compared to the case of the organic compound that generates the radical compound alone or the case where two or more compositions are uniformly mixed, It is conceivable that the capacity is reduced due to the charge / discharge cycle, and charge / discharge at a higher current density is possible, so that the battery operates efficiently.
[0019]
In the present invention, the radical compound is defined as a chemical species having an unpaired electron that does not form an electron pair, that is, a compound having a radical. Radicals are not zero in spin nuclear momentum and have various magnetic properties such as paramagnetism. In general, chemical bonds within molecules are caused by thermal decomposition, photolysis, radiolysis, and electron transfer. Generated by cutting. In addition, radicals are insulators with extremely high chemical reactivity, and their reactivity changes quickly by reaction between radicals or other stable molecules. The presence of such radicals can be observed by measuring an electron spin resonance spectrum (hereinafter referred to as an ESR spectrum) or the like.
[0020]
In the present invention, the electrochemical oxidation reaction and the reduction reaction are short-circuited by applying a voltage or applying a load to an active material electrically connected to an electrode disposed in an electrolyte solution. It is defined as a reaction involving the transfer of electrons that sometimes proceeds.
[0021]
Therefore, a battery having particles containing as an active material an organic compound that generates a radical compound in at least one of the electrochemical oxidation reaction and the reduction reaction of the present invention is a voltage applied to or applied to the active material. It is defined as a battery having particles containing an organic compound that generates a radical compound by a reaction involving the transfer of electrons that proceeds when short-circuited.
[0022]
In constructing the battery of the present invention, the spin concentration in the ESR spectrum of the radical compound is 10 ²⁰ Spin / g or more is preferable.
By setting such a spin concentration, a battery having high energy density, large capacity and excellent stability can be easily obtained.
[0023]
Further, in constituting the battery of the present invention, the particles are formed by integrating an organic compound that generates a radical compound in at least one of the electrochemical oxidation reaction and the reduction reaction and the electron conductive conductive material. It is preferable that the particles are made into particles.
By comprising in this way, an electrochemical oxidation reaction and a reduction reaction advance smoothly, and it can be set as a high output battery.
[0024]
Further, in constituting the battery of the present invention, it is preferable that the particles are integrated using a polymer substance as a binder.
By using a polymer substance as the binder, the binding is maintained even when the particles are deformed during battery operation, and the cycle life is excellent.
[0025]
Further, in constituting the battery of the present invention, in the particles, the electronically conductive substance is coated with an organic compound that generates a radical compound in at least one of the electrochemical oxidation reaction and the reduction reaction. It is preferable.
By covering in this way, the surface area of the organic compound that generates the radical compound can be increased, so that a battery with a large output density can be obtained.
[0026]
Further, in constituting the battery of the present invention, in the particles, an organic compound that generates a radical compound in at least one of the electrochemical oxidation reaction and the reduction reaction is coated with the electron conductive conductive material. It is preferable.
By covering in this way, a low impedance battery having a small internal resistance can be obtained.
[0027]
Further, in constituting the battery of the present invention, it is preferable that the electron conductive conductive material is a conductive polymer.
By using a conductive polymer, adhesion with an organic compound that generates a radical compound is improved, and a battery with a large output density can be obtained.
[0028]
In constituting the battery of the present invention, it is preferable that the electron conductive material is graphite or amorphous carbon.
By using graphite or amorphous carbon, a low impedance battery with low internal resistance can be obtained.
[0029]
Moreover, in constituting the battery of the present invention, the average particle size of the particles is preferably 0.1 to 500 μm.
By setting it as such an average particle diameter, the large capacity battery excellent in stability can be obtained easily.
[0030]
In constituting the battery of the present invention, it is preferable that the battery is a lithium secondary battery.
By comprising in this way, the high capacity | capacitance battery excellent in stability can be obtained.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
For example, as shown in FIG. 1, the embodiment of the battery of the present invention has a structure in which a negative electrode layer 1 and a positive electrode layer 2 are superposed via a separator 5 containing an electrolyte. In the present invention, the negative electrode layer 1 or the positive electrode layer 2 has particles containing, as an active material, an organic compound that generates a radical compound in at least one of an electrochemical oxidation reaction and a reduction reaction. It consists of a composite having at least two compositions.
[0032]
FIG. 2 shows a cross-sectional view of the stacked battery, in which the negative electrode current collector 3, the negative electrode layer 1, the separator 5 containing an electrolyte, the positive electrode layer 2, and the positive electrode current collector 4 are sequentially stacked. It has a structure.
[0033]
In the present invention, the method for laminating the positive electrode layer and the negative electrode layer is not particularly limited, and a multilayer laminate, a combination of laminates on both sides of the current collector, a wound one, or the like can be used.
[0034]
(1) Active material
(1) Material 1 (radical compound)
In the present invention, the kind of the radical compound generated in at least one of the electrochemical oxidation reaction and the reduction reaction is not particularly limited, but the effect of the invention and the workability in forming the electrode layer are not limited. In particular, an organic compound including a structural unit represented by the following general formula (1) and general formula (2) or any one of the general formulas is preferable.
[0035]
[Chemical 1]
[0036]
[Substituent R in General Formula (1) ¹ Is a substituted or unsubstituted alkylene group, alkenylene group, or arylene group, and X is an oxy radical group, a nitroxyl radical group, a sulfur radical group, a hydrazyl radical group, a carbon radical group, or a boron radical group. is there. ]
[0037]
[Chemical 2]
[0038]
[Substituent R in General Formula (2) ² And R ^Three Are mutually independent and are a substituted or unsubstituted alkylene group, alkenylene group, or arylene group, and Y is a nitroxyl radical group, a sulfur radical group, a hydrazyl radical group, or a carbon radical group. ]
[0039]
Examples of such radical compounds include oxy radical compounds, nitroxyl radical compounds, carbon radical compounds, nitrogen radical compounds, boron radical compounds, and sulfur radical compounds.
[0040]
Specific examples of the oxy radical compound include aryloxy radical compounds such as the following general formulas (3) to (4) and semiquinone radical compounds such as the following general formula (5).
[0041]
[Chemical 3]
[0042]
[In the general formulas (3) to (5), the substituent R ^Four ~ R ⁷ Are independent of each other, and are a hydrogen atom, a substituted or unsubstituted aliphatic or aromatic hydrocarbon group, a halogen group, a hydroxyl group, a nitro group, a nitroso group, a cyano group, an alkoxy group, an aryloxy group, or an acyl group. is there. ]
[0043]
Specific examples of the nitroxyl radical compound include a radical compound having a piperidinoxy ring such as the following general formula (6), a radical compound having a pyrrolidinoxy ring such as the following general formula (7), and the following general formula (8 And a radical compound having a nitronyl nitroxide structure such as the following general formula (9).
[0044]
[Formula 4]
[0045]
[In the general formulas (6) to (9), R ⁸ ~ R ^Ten Is the same as the contents of the above general formulas (3) to (5). ]
[0046]
Specific examples of the nitrogen radical compound include a radical compound having a trivalent hydrazyl group as represented by the following general formula (10), a radical compound having a trivalent ferdazyl group as represented by the following general formula (11), And a radical compound having an aminotriazine structure such as the following general formula (12).
[0047]
[Chemical formula 5]
[0048]
[In the general formulas (10) to (12), R ¹¹ ~ R ¹⁹ Is the same as the contents of the above general formulas (3) to (5). ]
[0049]
In the present invention, the production of a battery using the radical compound as described above as an active material for the electrode is also converted into the radical compound in at least one of the electrochemical oxidation reaction and the reduction reaction. A battery can also be manufactured using a non-radical compound.
[0050]
In the present invention, the concentration of the generated radical is not particularly limited, but the spin concentration in the ESR spectrum is 10 ²⁰ Spin / g or more is preferable. This is because the concentration of radicals is 10 ²⁰ This is because if the spin / g is not reached, the capacity of the battery becomes small, and the effect of the present invention of increasing the battery capacity may not be obtained. Therefore, from the viewpoint of increasing the capacity of the battery, the concentration of radicals is set to ²⁰ -10 ^{twenty three} A value within the range of spin / g is more preferable.
[0051]
However, in the present invention, a compound having delocalized electrons is not included in the radical compound even if it is an organic compound that can obtain a signal in the ESR spectrum. Examples of such compounds include conductive polymers that form solitons or polarons. These compounds generally have a low spin concentration of 10 ²⁰ Spin / g or less.
[0052]
In the present invention, an organic compound that generates a radical compound in at least one of an electrochemical oxidation reaction and a reduction reaction can be used as an active material of the positive electrode and the negative electrode or one of the electrodes. From the viewpoint, it is particularly preferable to use as a positive electrode active material.
[0053]
(2) Material 2
Moreover, when using these radical compounds as an active material of any one of a positive electrode and a negative electrode, the material listed below can be used as an active material of another electrode. That is, when an organic compound that generates a radical compound is used as the active material for the negative electrode layer, metal oxide particles, a disulfide compound, a conductive polymer, and the like are used as the active material for the positive electrode layer. Here, as the metal oxide, for example, LiMnO ₂ , Li _x Mn ₂ O _Four Lithium manganate having a spinel structure such as (0 <x <2) or lithium manganate having a spinel structure, MnO ₂ LiCoO ₂ , LiNiO ₂ Or Li _x V ₂ O _Five (0 <x <2) and the like, and disulfide compounds such as dithioglycol, 2,5-dimercapto-1,3,4-thiadiazole, S-triazine-2,4,6-triol, etc. Examples of the polymer include polyacetylene, polyphenylene, polyaniline, polypyrrole and the like.
In this invention, these positive electrode materials can be used individually by 1 type or in combination of 2 or more types.
In the present invention, the above-described conventionally known active material and an organic compound that generates radicals can be mixed to form a composite active material.
[0054]
On the other hand, when an organic compound that generates a radical compound is used as the active material of the positive electrode layer, the active material of the negative electrode layer is a single type of graphite, amorphous carbon, lithium metal, lithium alloy, and conductive polymer. Alternatively, a combination of two or more types is used.
Also, these shapes are not particularly limited. For example, in addition to a thin film of lithium metal, a bulk shape, a powdered shape, a fiber shape, a flake shape, or the like may be used. it can.
[0055]
(2) Active material particles
(I) Composition
The battery of the present invention includes particles containing an organic compound that generates the radical compound as an active material (hereinafter, may be referred to as active material particles), and the particles are in a region having at least two compositions. It is comprised from the composite which consists of. In this composite, at least two kinds of compositions are combined to form one particle while maintaining the respective regions. In the present invention, the radical compound is generated as the composition of at least one region. Contains organic compounds.
Therefore, the composite is not included in which at least two or more compositions are mixed and each region is uniformly dispersed throughout.
[0056]
In the present invention, the composition of the region other than the region of the organic compound that generates the radical compound is not particularly limited, but in terms of the effect of the invention, the dissolution of the organic compound that generates the electron conductive conductive material and the radical compound is prevented. It is preferable to use materials such as agents, stabilizers, and immobilization carriers. Among these, examples of the electron conductive conductive material include conductive polymers such as graphite, amorphous carbon, metal, polyaniline and polypyrrole, or conductive organic such as tetracyanoquinodimethane-tetrathiafulvalene complex. A complex etc. are mentioned. Examples of the organic compound dissolution inhibitor and stabilizer that generate radical compounds include polymer compounds such as polyethylene, polyvinyl alcohol, polytetrafluoroethylene, and polyurethane. In addition, examples of the immobilization simple substance of the organic compound that generates the radical compound include the above-described polymer compound and zeolite.
[0057]
In the present invention, the mode of combination of at least two types of composition regions is not particularly limited, and each region is unevenly distributed and mosaic combination, and one region is covered with the other region. Such as a combination in which one region is surrounded by another small region, and a combination in which the other region is finely dispersed in one region. Is mentioned.
[0058]
Examples of such combinations are shown in FIGS. Here, (a) is a combination in which the region of the radical compound 8 is covered with the region of the conductive substance 9, (b) is a combination in which the region of the conductive substance 9 is covered with the region of the radical compound 8, and (c) is a radical. A combination in which the region of the compound 8 is surrounded by a small region of the conductive material 9, and (d) is a combination in which the region of the conductive material 9 is surrounded by a small region of the radical compound 8.
[0059]
(Ii) Integration
In the present invention, it is preferable that at least two or more composition regions constituting the active material particles are combined and integrated as described above. In this case, the integration method is not particularly limited, and a method in which two or more composition regions are simply brought into contact with each other, a method in which a polymer substance is used as a binder, and the like are integrated. Can be used. Examples of the polymer material used for the binder include, for example, acid-modified products of polyethylene and polypropylene, polymers such as polyvinyl alcohol, polyvinyl acetate, and polyurethane, and fluorine-based polymers such as tetrafluoroethylene and polyvinylidene fluoride. One kind alone or a combination of two or more kinds of molecules and the like can be mentioned.
[0060]
(Iii) Average particle size
In this invention, it is preferable that the average particle diameter of active material particle shall be 0.1-500 micrometers. This is because when the average particle size is less than 0.1 μm, the particles are likely to aggregate, and the internal resistance may increase due to insufficient mixing with the electrolyte. This is because it may be difficult to take out the capacity due to the low charge transfer rate from the inside of the substance particles.
For this reason, the average particle diameter of the active material particles is more preferably 0.1 to 50 μm, and further preferably 0.5 to 10 μm.
[0061]
(Iv) Composition ratio
In the present invention, the composition ratio of the active material particles is not particularly limited, but when the total weight of the active material particles is 100% by weight, the content of the organic compound that generates the radical compound is 10 to 99% by weight. % Is preferable. This is because when the content of the organic compound that generates the radical compound is less than 10% by weight, the capacity becomes small, and the characteristics of the present invention of a large-capacity battery may be lost. This is because if the ratio exceeds%, the internal resistance increases and the impedance may increase.
For this reason, the content of the organic compound that generates the radical compound is more preferably 50 to 99% by weight, and still more preferably 80 to 97% by weight.
[0062]
(3) Electrode constituent materials
In this invention, in order to perform an electrode reaction more smoothly, the conductive support material and resin binder which are used for the conventional battery can be used. Examples of such a conductive auxiliary material include carbonaceous fine particles such as acetylene black, fibers, and the like. Examples of the resin binder include polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, styrene-butadiene copolymer elastomer, polypropylene, polyimide, and various urethanes.
[0063]
In the present invention, a current collector can be used to collect charges generated from the electrode active material, as in the conventional battery. As these materials, metal foils such as nickel, aluminum, copper, gold, silver, and stainless steel, metal flat plates, mesh electrodes, and carbon electrodes can be used. Further, such a current collector can have a catalytic effect.
[0064]
(4) Separator and sealing material
The separator 5 in the present invention prevents the positive electrode layer and the negative electrode layer from contacting each other, and a material such as a porous film or a nonwoven fabric can be used. Further, such a separator is preferably configured to contain an electrolyte.
However, when an ion conductive polymer is used as the electrolyte, the separator itself can be omitted.
Further, the sealing material 6 in the present invention is not particularly limited, and a conventionally known material used for a battery exterior is used.
[0065]
(5) Electrolyte
In the present invention, the electrolyte performs charge carrier transport between both electrodes of the negative electrode layer 1 and the positive electrode layer 2. ^-Five -10 ^-1 It has an ionic conductivity of S / cm.
In the present invention, for example, an electrolyte solution in which an electrolyte salt is dissolved in a solvent can be used as the electrolyte. As such an electrolyte salt, for example, LiPF ₆ LiClO _Four , LiBF _Four , LiCF _Three SO _Three , Li (CF _Three SO ₂ ) ₂ N, Li (C ₂ F _Five SO ₂ ) ₂ N, Li (CF _Three SO ₂ ) _Three C, Li (C ₂ F _Five SO ₂ ) _Three Conventionally known materials such as C can be used.
Examples of the electrolyte salt solvent include ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, γ-butyrolactone, tetrahydrofuran, dioxolane, sulfolane, dimethylformamide, dimethylacetamide, and N-methyl-2-pyrrolidone. An organic solvent such as can be used. In the present invention, these solvents can be used alone or as a mixed solvent of two or more.
[0066]
Furthermore, in the present invention, a solid electrolyte can be used as the electrolyte. Examples of the polymer compound used in such a solid electrolyte include polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-ethylene copolymer, vinylidene fluoride-monofluoroethylene copolymer, and fluorine. Vinylidene fluoride-trifluoroethylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, etc., and acrylonitrile-methyl Methacrylate copolymer, acrylonitrile-methyl acrylate copolymer, acrylonitrile-ethyl methacrylate copolymer, acrylonitrile-ethyl acrylate copolymer, acrylonitrile-methacrylic acid copolymer, acrylonitrile- Acrylic acid copolymers, acrylonitrile - acrylonitrile polymers such as vinyl acetate copolymer, further polyethylene oxide, ethylene oxide - propylene oxide copolymers, and polymers of these acrylates body or methacrylate body thereof. The solid electrolyte may be a gel obtained by adding an electrolytic solution to these polymer compounds, or may be used as it is with only the polymer compound.
[0067]
(6) Shape
Further, the shape of the battery is not particularly limited, and can be applied to shapes of a cylindrical battery, a coin-type battery, a square battery, a film-type battery, a button-type battery, and the like.
[0068]
【Example】
Hereinafter, the present invention will be described more specifically, but the present invention is not limited to these examples.
[0069]
Example 1
(1) Battery production
In a dry box equipped with a gas purifier, 100 mg of galvinoxyl radical represented by the following formula (13) is placed in a glass container under an argon gas atmosphere, and 200 mg of tetrahydrofuran (hereinafter abbreviated as THF) is added. And dissolved. To this solution, 10 mg of graphite particles having an average particle diameter of 2 μm was added, and the whole was developed on a filter paper to evaporate THF. Thereafter, solid matter on the filter paper was scraped off, and graphite particles having an average particle diameter of 2.1 μm coated with galvinoxyl radicals were obtained. When the ESR spectrum of this particle was measured, its spin concentration was 10 ²⁰ Spin / g or more.
[0070]
[Chemical 6]
[0071]
Subsequently, 110 mg of the obtained particles were placed on the surface of an aluminum foil (area: 1.5 cm × 1.5 cm, thickness: 100 μm) provided with a lead wire, and the entire thickness was uniform with a wire bar. When developed and covered with a Teflon plate and pressurized at a pressure of 20 MPa, an electrode layer made of graphite particles coated with galvinoxyl radicals was formed on the aluminum foil.
[0072]
Next, 600 mg of vinylidene fluoride-hexafluoropropylene copolymer and 1 mol / l LiPF ₆ Was mixed with 1,400 mg of an electrolytic solution composed of a dimethyl carbonate solution containing an electrolyte salt, and 11.3 g of THF was further added thereto, followed by stirring at room temperature. After the vinylidene fluoride-hexafluoropropylene copolymer is dissolved, this solution is applied onto a stepped glass plate, left to stand at room temperature for 1 hour, and THF is naturally dried, and a gel electrolyte having a thickness of 1 mm is cast. A film (hereinafter referred to as a gel electrolyte membrane) was obtained.
[0073]
Next, a gel electrolyte film cut out to 20 mm × 20 mm is laminated on an aluminum foil on which an electrode layer made of graphite particles coated with galvinoxyl radicals is formed, and a lithium-laminated copper foil having a lead wire ( After stacking a lithium foil film thickness of 30 μm and a copper foil film thickness of 20 μm, the whole was sandwiched between 5 mm thick polytetrafluoroethylene sheets, and pressure was applied to produce a battery.
[0074]
(2) Battery evaluation
Using the battery produced as described above as a sample, discharging was performed at a constant current of 0.1 mA using an electrode made of graphite particles coated with galvinoxyl radical as a positive electrode and a lithium-laminated copper foil as a negative electrode. As a result, a flat voltage portion was observed in the vicinity of 2.3 V, and it was confirmed that the battery was operating. Furthermore, when this battery was repeatedly charged and discharged, the capacity after 100 cycles was 80% or more of the initial capacity, and it was confirmed that this battery operates as a chargeable / dischargeable secondary battery.
[0075]
(Comparative Example 1)
(1) Battery production
The galvinoxyl radical was dissolved in THF under the same conditions as in Example 1, and spread on the aluminum foil used in Example 1 without being coated with graphite particles as it was. When THF was evaporated and dried, the aluminum foil was obtained. An electrode layer made of galvinoxyl radical was formed on the top.
Next, a gel electrolyte membrane was laminated on the aluminum foil on which an electrode layer made of galvinoxyl radical was formed, and a lithium-laminated copper foil was laminated in the same manner as in Example 1, and then a battery was produced by applying pressure. .
[0076]
(2) Battery evaluation
Using the battery produced as described above as a sample, discharging was performed at a constant current of 0.1 mA using a positive electrode as an electrode made of galvinoxyl radical and a negative electrode as a copper foil laminated with lithium. As a result, it was confirmed that the voltage flat portion was slightly observed in the vicinity of 2.3 V and operated as a battery. However, the voltage immediately decreased after discharge and the capacity became 10% or less of Example 1. Furthermore, when this battery was repeatedly charged and discharged, the capacity after 10 cycles was 50% or less of the initial capacity, and it was confirmed that the secondary battery was inferior in cycle life.
[0077]
(Comparative Example 2)
(1) Battery production
1 mol / l LiPF as an electrolyte salt in the glass container of Example 1 ₆ Containing 1.5 g of THF, 100 mg of galvinoxyl radical was dissolved. To this solution, 10 mg of the graphite particles used in Example 1 and 1 mg of vinylidene fluoride-hexafluoropropylene copolymer were added to obtain a black slurry.
This slurry was spread on an aluminum foil (area: 1.5 cm × 1.5 cm, thickness: 100 μm) with lead wires, and the whole was made uniform with a wire bar, and then dried at room temperature. As a result, an electrode layer containing galvinoxyl radicals was formed on the aluminum foil. This electrode layer was presumed that graphite particles were dispersed in a medium composed of a vinylidene fluoride-hexafluoropropylene copolymer in which galvinoxyl radicals were uniformly dissolved.
[0078]
Next, a gel electrolyte was laminated on an aluminum foil on which an electrode layer containing galvinoxyl radicals was formed in the same manner as in Example 1, a lithium-laminated copper foil was overlaid, and then a pressure was applied to produce a battery.
[0079]
(2) Battery evaluation
Using the battery prepared as described above as a sample, discharging was performed at a constant current of 0.1 mA using an electrode layer containing a galvinoxyl radical as a positive electrode and a lithium-laminated copper foil as a negative electrode. As a result, a voltage flat portion was observed near 2.3 V, and it was confirmed that the device operated as a battery. Thereafter, the voltage gradually decreased, and the capacity became 70% or less of Example 1. Furthermore, when this battery was repeatedly charged and discharged, the capacity after 50 cycles was 50% or less of the initial capacity, and it was confirmed that the secondary battery was inferior in cycle life.
[0080]
(Comparative Example 3)
(1) Battery production
1 mol / l LiPF as an electrolyte salt in the glass container of Example 1 ₆ 1.5 g of THF containing was added, and 10 mg of the graphite particles used in Example 1 and 6 mg of vinylidene fluoride-hexafluoropropylene copolymer were added thereto to obtain a black slurry containing no galvinoxyl radical. It was.
This slurry was spread on an aluminum foil by the same method as in Comparative Example 2 and dried to form an electrode layer.
Next, a gel electrolyte was laminated on the electrode layer on the aluminum foil in the same manner as in Example 1, and a lithium-laminated copper foil was overlaid, and then a pressure was applied to produce a battery.
[0081]
(2) Battery evaluation
Using the battery produced as described above as a sample, discharging was performed at a constant current of 0.1 mA using the electrode layer on the aluminum foil as the positive electrode and the lithium-laminated copper foil as the negative electrode. As a result, it was confirmed that the voltage flat portion was not recognized and the battery did not operate.
[0082]
(Example 2)
(1) Battery production
Polyaniline particles having an average particle size of 2.2 μm coated with galvinoxyl radicals were obtained in the same manner as in Example 1 except that polyaniline powder having an average particle size of 2 μm was used instead of the graphite powder of Example 1. When the ESR spectrum of the polyaniline particles was measured, the spin concentration was 10 ²⁰ Spin / g or more.
[0083]
The particles were spread on an aluminum foil in the same manner as in Example 1, and pressure was applied to form an electrode layer composed of polyaniline particles coated with galvinoxyl radicals.
Next, a gel electrolyte was laminated on the aluminum foil on which an electrode layer composed of polyaniline particles coated with galvinoxyl radicals was formed in the same manner as in Example 1, and after laminating a lithium-laminated copper foil, pressure was applied. A battery was produced.
[0084]
(2) Battery evaluation
Using the battery prepared as described above as a sample, discharging was performed at a constant current of 0.1 mA using an electrode made of polyaniline particles coated with galvinoxyl radical as a positive electrode and a lithium-laminated copper foil as a negative electrode. As a result, a flat voltage portion was observed in the vicinity of 2.3 V, and it was confirmed that the device was operating as a battery. Furthermore, when this battery was repeatedly charged and discharged, the capacity after 100 cycles was 80% or more of the initial capacity, and it was confirmed that this battery operates as a chargeable / dischargeable secondary battery.
[0085]
Example 3
(1) Battery production
1 mol / l LiPF as an electrolyte salt in the glass container of Example 1 ₆ Containing 1.5 g of THF, 100 mg of galvinoxyl radical was dissolved. To this solution, 600 mg of vinylidene fluoride-hexafluoropropylene copolymer used in Example 1 was added to form a slurry. This slurry was poured into a large amount of water containing 0.1% by weight of a non-ionic surfactant (manufactured by Kao Corporation, Emulgen 109P (trade name)), stirred vigorously, and galvinoxyl radical and vinylidene fluoride. -A dispersion of particles made of hexafluoropropylene copolymer was prepared.
[0086]
Next, graphite particles having an average particle size of 0.1 μm were put into this dispersion and allowed to stand for 12 hours. As a result, particles composed of galvinoxyl radical and vinylidene fluoride-hexafluoropropylene copolymer, and graphite particles Precipitated. Next, the supernatant was removed, and the remaining slurry was spread on a filter paper to evaporate THF. Thereafter, solid matter was scraped off from the surface of the filter paper, and particles having an average particle diameter of 5 μm whose surface was coated with fine graphite particles were obtained. This particle contains a galvinoxyl radical, and when the ESR spectrum is measured, the spin concentration is 10. ²⁰ Spin / g or more.
The particles were spread on an aluminum foil in the same manner as in Example 1, and an electrode layer composed of galvinoxyl radicals coated with graphite particles was formed by applying pressure.
[0087]
Next, a gel electrolyte was laminated on an aluminum foil formed with an electrode layer composed of galvinoxyl radical particles coated with graphite particles in the same manner as in Example 1, and after laminating a lithium-laminated copper foil, pressure was applied. In addition, a battery was produced.
[0088]
(2) Battery evaluation
Using the battery produced as described above as a sample, discharge was performed at a constant current of 0.1 mA using an electrode made of galvinoxyl radical particles coated with graphite particles as a positive electrode and a lithium-laminated copper foil as a negative electrode. As a result, a flat voltage portion was observed in the vicinity of 2.3 V, and it was confirmed that the device was operating as a battery. Furthermore, when this battery was repeatedly charged and discharged, the capacity after 100 cycles was 90% or more of the initial capacity, and it was confirmed that this battery operates as a chargeable / dischargeable secondary battery.
[0089]
Example 4
(1) Battery production
2,2,6,6-Tetramethylpiperidi is obtained in the same manner as in Example 1 except that 2,2,6,6-tetramethylpiperidyloxy radical is used in place of the galvinoxyl radical of Example 1. Graphite particles having an average particle diameter of 2.1 μm coated with roxy radicals were obtained. When the ESR spectrum of the particles containing 2,2,6,6-tetramethylpiperidyloxy radical was measured, the spin concentration was 10 ²⁰ Spin / g or more.
The particles were spread on an aluminum foil in the same manner as in Example 1, and an electrode layer composed of graphite particles coated with 2,2,6,6-tetramethylpiperidyloxy radical was formed by applying pressure. .
[0090]
Next, a gel electrolyte was laminated on the aluminum foil on which the electrode layer made of graphite particles coated with 2,2,6,6-tetramethylpiperidyloxy radical was formed in the same manner as in Example 1, and lithium-laminated copper After overlapping the foils, pressure was applied to produce a battery.
[0091]
(2) Battery evaluation
Using the battery produced as described above as a sample, an electrode made of graphite particles coated with 2,2,6,6-tetramethylpiperidyloxy radical was used as a positive electrode, and a lithium-bonded copper foil as a negative electrode, and a constant current of 0.1 mA was used. Discharge was performed with current. As a result, a flat voltage portion was observed in the vicinity of 3.5 V, and it was confirmed that the device was operating as a battery. Furthermore, when this battery was repeatedly charged and discharged, the capacity after 100 cycles was 80% or more of the initial capacity, and it was confirmed that this battery operates as a chargeable / dischargeable secondary battery.
[0092]
(Example 5)
(1) Battery production
Average grains coated with diphenylpicrylhydrazyl radical in the same manner as in Example 1 except that diphenylpicrylhydrazyl radical represented by the following formula (14) is used instead of galvinoxyl radical in Example 1. Graphite particles having a diameter of 2.1 μm were obtained. When the ESR spectrum of the particle containing the diphenylpicrylhydrazyl radical was measured, the spin concentration was 10 ²⁰ Spin / g or more.
[0093]
[Chemical 7]
[0094]
The particles were spread on an aluminum foil in the same manner as in Example 1, and pressure was applied to form an electrode layer composed of graphite particles coated with diphenylpicrylhydrazyl radical.
Next, on the aluminum foil in which the electrode layer made of graphite particles coated with diphenylpicrylhydrazyl radical was formed, the gel electrolyte was laminated in the same manner as in Example 1, and the lithium-laminated copper foil was overlaid. To prepare a battery.
[0095]
(2) Battery evaluation
Using the battery produced as described above as a sample, discharge was performed at a constant current of 0.1 mA using an electrode layer made of graphite particles coated with diphenylpicrylhydrazyl radical as a positive electrode and a lithium-laminated copper foil as a negative electrode. As a result, a flat voltage portion was observed in the vicinity of 2.6 V, and it was confirmed that the device was operating as a battery. Furthermore, when this battery was repeatedly charged and discharged, the capacity after 100 cycles was 80% or more of the initial capacity, and it was confirmed that this battery operates as a chargeable / dischargeable secondary battery.
[0096]
【The invention's effect】
According to the present invention, in a battery having particles containing an organic compound as an active material, which includes at least a positive electrode, a negative electrode, and an electrolyte as components, and generates an organic compound in at least one of an electrochemical oxidation reaction and a reduction reaction. By using these particles as a composite composed of at least two regions of composition, a battery having high energy density during charge / discharge, large capacity and excellent stability can be provided.
[Brief description of the drawings]
FIG. 1 is a front sectional view showing an embodiment of a battery of the present invention.
FIG. 2 is a central longitudinal sectional view showing one embodiment of a battery of the present invention.
FIG. 3 is a schematic view showing an example of the structure of the composite of the present invention.
[Explanation of symbols]
1 Negative electrode layer
2 Negative electrode current collector
3 Positive electrode layer
4 Positive current collector
5 Separator
6 Sealing material
7 Lead terminal
8 Radical compounds
9 Conductive substances

Claims (12)

A battery comprising particles containing, as active materials, an organic compound that includes at least a positive electrode, a negative electrode, and an electrolyte, and that generates a radical compound in at least one of an electrochemical oxidation reaction and a reduction reaction. Ri composite der consisting region of two or more compositions,
The secondary particles, wherein the particles are particles in which an organic compound that generates a radical compound in at least one of the electrochemical oxidation reaction and the reduction reaction and an electron conductive conductive material are integrated. battery. 2. The radical according to claim 1, wherein the radical compound is selected from the group consisting of an oxy radical compound, a nitroxyl radical compound, a carbon radical compound, a nitrogen radical compound, a boron radical compound, and a sulfur radical compound. Next battery. The secondary battery according to claim 1, wherein the spin concentration of the radical compound in an electron spin resonance spectrum is 10 ²⁰ spins / g or more. The secondary battery according to claim 1 , wherein the particles are integrated using a polymer substance as a binder. The integrated particle is characterized in that the electronically conductive substance is coated with an organic compound that generates a radical compound in at least one of the electrochemical oxidation reaction and the reduction reaction. Item 11. The secondary battery according to Item 1 . The integrated particle is characterized in that an organic compound that generates a radical compound in at least one of the electrochemical oxidation reaction and the reduction reaction is coated with the electron conductive conductive material. Item 11. The secondary battery according to Item 1 . The secondary battery according to claim 1 , wherein the electron conductive conductive material is a conductive polymer. The secondary battery according to claim 1 , wherein the electronically conductive material is graphite or amorphous carbon. The secondary battery according to claim 1 , wherein an average particle diameter of the particles is 0.1 to 500 μm. The secondary battery according to claim 1 , wherein the secondary battery is a lithium secondary battery. The radical compound is represented by the following formula (13):
And graphite particles coated with 2,2,6,6-tetramethylpiperidyloxy radical, and the following formula (14):
The secondary battery according to claim 2, wherein the secondary battery is selected from the group consisting of diphenylpicrylhydrazyl radicals represented by: The composite is represented by the following formula (13):
Graphite particles coated with a galvinoxyl radical represented by the formula, polyaniline particles coated with a galvinoxyl radical represented by the formula (13), and represented by the formula (13) coated with graphite particles. Particles containing galvinoxy radical, graphite particles coated with 2,2,6,6-tetramethylpiperidyloxy radical, and the following formula (14)
The secondary battery according to claim 1, wherein the secondary battery is selected from the group consisting of graphite particles coated with a diphenylpicrylhydrazyl radical represented by: