WO2013042706A1

WO2013042706A1 - Organic molecule spin battery

Info

Publication number: WO2013042706A1
Application number: PCT/JP2012/074000
Authority: WO
Inventors: 武治工位; 和信佐藤; 靖森田
Original assignee: 公立大学法人大阪市立大学; 国立大学法人大阪大学
Priority date: 2011-09-20
Filing date: 2012-09-20
Publication date: 2013-03-28
Also published as: JPWO2013042706A1

Abstract

The present invention provides a rare metal-free active material able to obtain a secondary battery with high capacity and excellent cycle characteristics, and a secondary battery using this active material. The present invention is a cathode active material containing an organic compound having a skeleton of graphene fragments or a derivative thereof.

Description

Organic molecular spin battery

The present invention relates to an organic molecular spin battery and a material suitable for the battery.

In recent years, with the expansion of the market for mobile phones, portable electronic devices and information device terminals, the demand for high-power, high-performance batteries with high energy density is increasing. 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 associated with charge transfer is developed. In particular, a lithium ion secondary battery having a large energy density is ubiquitous. Currently widely used as an energy storage device.

Lithium ion secondary batteries usually use lithium-containing transition metal oxides for the positive electrode and carbon materials for the negative electrode as the electrode active material, and use lithium ion insertion and desorption reactions for these active materials. Charging / discharging. However, since the existing lithium secondary battery requires LiCoO ₂ (lithium cobaltate) containing rare metal as a positive electrode active material, it faces a problem of resource prices in the near future. On the other hand, from the aspect of technological innovation, expectations for higher performance of secondary batteries, such as higher current capacity and cycle characteristics, are increasing. For this reason, there is a demand for a secondary battery having a high capacity and excellent cycle characteristics using a rare metal-free material as an active material.

Batteries using conductive polymers, organic sulfur compounds, etc. as electrode active materials have been proposed as rare metal-free materials. For example, Patent Document 1 discloses a battery using a conductive polymer as a positive electrode or negative electrode active material. This battery is based on the principle of doping and dedoping of electrolyte ions with respect to a conductive polymer. The dope reaction herein is defined as a reaction that stabilizes excitons (excitons) such as charged solitons and polarons generated by an electrochemical oxidation reaction or reduction reaction of 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 that electrochemically oxidizes or reduces exciton stabilized by a counter ion. A battery using a conductive polymer as an active material has been expected as a high-capacity density 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. However, in conductive polymers, excitons generated by electrochemical redox reactions are delocalized over a wide range of π-electron conjugated systems, and they interact to cause electrostatic repulsion and radical disappearance. Inevitably exist. This process limits the concentration of the generated charged radicals, excitons, etc., 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. Therefore, although a battery using a conductive polymer as an electrode material has a certain effect in terms of weight reduction, a battery having a large energy density has not been obtained so far. 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 the technology for increasing the capacity is still insufficient.

Thus, various types of batteries have been proposed in order to realize a secondary battery having a high capacity and excellent cycle characteristics by using a rare metal-free material as an electrode active material. However, nothing that satisfies the requirements has yet been obtained.

U.S. Pat.No. 4,442,187

An object of the present invention is to provide a rare metal-free active material and a secondary battery using the active material based on a design philosophy that provides a secondary battery having a high capacity and excellent cycle characteristics.

As a result of intensive studies in view of the above problems, the present inventors have used a compound having a graphene fragment skeleton as a positive electrode active material (particularly, imparting quantum mechanical orbital degeneracy to frontier molecular orbitals ( Degenerate frontier molecular orbitals), and the result of molecular design that electrons carrying electricity during charge and discharge processes occupy these orbitals partially or entirely and having a specific structure) It has been found that a resolved secondary battery can be obtained. The present invention has been completed as a result of further research based on such knowledge. That is, the present invention includes the inventions according to items 1-1 to 2-12 below.

Item 1-1. A positive electrode active material for a secondary battery, comprising an organic compound having a graphene fragment skeleton or a derivative thereof.

Item 1-2. Item 12. The positive electrode active material for a secondary battery according to Item 1-1, wherein the organic compound having a graphene fragment skeleton or a derivative thereof is an open-shell molecular spin having a degenerate frontier molecular orbital or an intermediate-state closed-shell structure molecule .

Item 1-3. The organic compound having a graphene fragment skeleton or a derivative thereof is represented by the general formula (1):

[In the formula, a double line composed of a solid line and a broken line is a single bond or a double bond. ]
Item 11. The secondary battery positive electrode active material according to Item 1-1 or 1-2, which has a chemical molecular structure represented by:

Item 1-4. The organic compound having a graphene fragment skeleton or a derivative thereof is represented by the general formula (2):

[Wherein, R ¹ to R ³ are the same or different and each is an alkyl group having 1 to 6 carbon atoms or a halogen atom; a double line composed of a solid line and a broken line is a single bond or a double bond. ]
Item 4. The positive electrode active material for a secondary battery according to any one of Items 1-1 to 1-3, comprising the organic compound represented by

Item 1-5. General formula (2):

[Wherein, R ¹ to R ³ are the same or different and each is an alkyl group having 1 to 6 carbon atoms or a halogen atom; a double line composed of a solid line and a broken line is a single bond or a double bond. ]
Item 5. The positive electrode active material for a secondary battery according to Item 1-4, which contains a salt composed of an anion derived from the organic compound represented by the above and a metal cation.

Item 1-6. Item 6. The secondary battery positive electrode active material according to Item 1-4 or 1-5, wherein R ¹ to R ³ are all halogen atoms.

Item 1-7. Item 7. The secondary battery positive electrode active material according to any one of Items 1-4 to 1-6, wherein R ¹ to R ³ are all bromine atoms.

Item 1-8. Item 8. A secondary battery positive electrode comprising the secondary battery positive electrode active material according to any one of Items 1-1 to 1-7.

Item 1-9. Item 9. The secondary battery positive electrode according to Item 1-8, further comprising conductive carbon fiber.

Item 1-10. Item 10. An organic molecular spin battery comprising the positive electrode according to Item 1-8 or 1-9.

Item 1-11. Item 11. The organic molecular spin battery according to Item 1-10, further comprising an electrolytic solution containing a lithium compound.

Item 2-1. A positive electrode active material for a secondary battery comprising an organic compound having a graphene fragment skeleton or a derivative thereof, wherein the organic compound having a graphene fragment skeleton or a derivative thereof is
General formula (2):

[Wherein, R ¹ to R ³ are the same or different and each represents an alkyl group having 1 to 6 carbon atoms, a halogen atom; a double line composed of a solid line and a broken line is a single bond or a double bond. ]
A salt composed of an anion derived from an organic compound represented by formula (I) and a metal cation, and general formula (2 ′):

[Wherein R ¹ to R ³ are the same or different and each is a halogen atom; a double line composed of a solid line and a broken line is a single bond or a double bond. ]
The positive electrode active material for secondary batteries containing at least 1 sort (s) chosen from the group which consists of the organic compound shown by these, or its derivative (s).

Item 2-2. Item 2. The positive electrode active material for a secondary battery according to Item 2-1, wherein the organic compound having a graphene fragment skeleton or a derivative thereof has a degenerate frontier molecular orbital.

Item 2-3. Item 2-1 or 2-2, wherein the organic compound having a graphene fragment skeleton or a derivative thereof contains a salt composed of an anion derived from the organic compound represented by the general formula (2) and a metal cation. The positive electrode active material for secondary batteries.

Item 2-4. Item 4. The secondary battery positive electrode active material according to any one of Items 2-1 to 2-3, wherein, in the general formula (2), R ¹ to R ³ are the same or different and all are halogen atoms.

Item 2-5. Item 3. The secondary battery positive electrode active material according to Item 2-1, wherein the organic compound having a graphene fragment skeleton or a derivative thereof contains the organic compound represented by the general formula (2 ′) or a derivative thereof.

Item 2-6. Item 6. The positive electrode active material for secondary battery according to any one of Items 2-1 to 2-5, wherein in the general formulas (2) and (2 ′), R ¹ to R ³ are all bromine atoms.

Item 2-7. Item 6. A secondary battery positive electrode comprising the secondary battery positive electrode active material according to any one of Items 2-1 to 2-4.

Item 2-8. Item 8. The secondary battery positive electrode according to Item 2-7, further comprising conductive carbon fiber.

Item 2-9. A positive electrode for a secondary battery, comprising a positive electrode active material for a secondary battery containing an organic compound having a graphene fragment skeleton or a derivative thereof, and conductive carbon fiber.

Item 2-10. Item 10. The secondary battery positive electrode according to Item 2-9, wherein the organic compound having a graphene fragment skeleton or a derivative thereof has a degenerate frontier molecular orbital.

Item 2-11. Item 10. An organic molecular spin battery comprising the positive electrode according to any one of Items 2-7 to 2-10.

Item 2-12. Item 11. The organic molecular spin battery according to Item 2-10, further comprising an electrolytic solution containing a lithium compound.

According to the present invention, an organic compound having a graphene fragment skeleton or a derivative thereof is used as a rare metal-free positive electrode active material (particularly, the frontier molecular orbital has quantum mechanical orbital degeneracy (degenerate frontier molecular orbital), Furthermore, the secondary battery with high capacity and excellent cycle characteristics is provided by the molecular design that the electrons that carry electricity during the charge / discharge process occupy these orbits partially or entirely and have a specific structure) can do.

6 is an energy level diagram showing the results of quantum chemical calculations for 6OPO in Comparative Example 1, (t-Bu) ₃ TOT in Example 1, and Br ₃ TOT in Example 4. FIG. FIG. ₄ is a CV curve diagram showing the redox behavior of the Bu ₄ N ⁺ salt of (t-Bu) ₃ TOT of Reference Example 1 and the Bu ₄ N ⁺ salt of Br ₃ TOT anion of Reference Example 2. It is a graph which shows the result of the charging / discharging characteristic and cycle characteristic of each coin type battery of Comparative Example 2 (a) and Example 5 (b). The red line is the first cycle, the blue line is the second cycle, and the black is the other cycle. It is a graph which shows the result at the time of making charging / discharging conditions 2C (a) and 3C (b) about the charging / discharging characteristic of the coin-type battery of the comparative example 2. The red line is the first cycle, the blue line is the second cycle, and the black is the other cycle. 6 is a graph showing the results of 100 cycles to 500 cycles with respect to the charge / discharge characteristics of the coin-type battery of Comparative Example 2. Charging / discharging characteristics of the coin-type battery of Example 9 when charged and discharged at 1C (a) (red line is the first cycle, blue line is the second cycle, black is the other cycle) and 1C (red) or It is a graph which shows the result of cycling characteristics (b) when charging / discharging by 2C (blue).

1. Cathode Active Material The cathode active material of the present invention includes an organic compound having a graphene fragment skeleton or a derivative thereof.

In particular, an organic compound having a graphene fragment skeleton or a derivative thereof is
General formula (2):

[Wherein R ¹ to R ³ are the same or different and each is a halogen atom; a double line composed of a solid line and a broken line is a single bond or a double bond. ]
It is preferable to contain at least 1 sort (s) chosen from the group which consists of the organic compound or its derivative shown by these. Details will be described below.

The organic compound having a graphene fragment skeleton or a derivative thereof is particularly preferably an open-shell organic molecular system having a degenerate frontier molecular orbital. Here, “degenerate” in a degenerate frontier molecular orbital means that there are multiple quantum states with the same energy level, and appears in the microscopic physical reality of molecular / atomic size. Nature. This degeneracy is derived from group-theoretic degeneracy derived from the geometry and three-dimensional structure of the molecule, or from topological symmetry created by controlling the position of atoms constituting the molecule and the position of substituents to be introduced. It may be degenerate. An “open-shell organic molecule” is an organic molecule that has one or more unpaired electrons (electrons that do not participate in chemical bonding) in the molecule and has intrinsic quantum properties derived from electron spin angular momentum. Refers to that.

In the present invention, the graphene fragment structure is, for example,

[In the formula, a double line composed of a solid line and a broken line is a single bond or a double bond. ]
Etc., specifically,

Etc.

As an organic compound having a graphene fragment skeleton or a derivative thereof, specifically, the general formula (1):

[In the formula, a double line composed of a solid line and a broken line is a single bond or a double bond. ]
What has the structure shown by these is preferable.

Specifically, the general formula (2):

[Wherein, R ¹ to R ³ are the same or different and each is an alkyl group having 1 to 6 carbon atoms or a halogen atom; the double line consisting of a solid line and a broken line is the same as described above. ]
An organic compound represented by or a derivative thereof is preferable.

In particular, the compound represented by the general formula (2) or a derivative thereof is

[Wherein, R ¹ to R ³ and the double line composed of a solid line and a broken line are the same as described above. ]
Thus, 4 electrons can be exchanged with one molecule. That is, in the degenerate orbital oxidation-reduction reaction, the energy gap between degenerate molecular orbitals occupied by intervening electrons can be controlled, and a large number of electrons can be involved (for example, a phenalenyl skeleton that exchanges two electrons). Therefore, the current capacity can be dramatically improved.

In the general formula (2), the bond between the oxygen atom and the graphene fragment skeleton may be a single bond or a double bond. Even in the case of a single bond, neutral radicals, anions, and charged radicals are delocalized and can exist stably. The compound often has a structure in which planar compounds are stacked. For this reason, radicals, anions, and the like, which are reaction sites of the oxidation-reduction reaction, are exposed to the outside, and a stable active material is obtained without reducing the reactivity.

In the general formula (2), R ¹ to R ³ are the same or different and each represents an alkyl group having 1 to 6 carbon atoms or a halogen atom. Specific examples include a methyl group, an ethyl group, a propyl group, a t-butyl group, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Of these, a halogen atom, particularly a bromine atom, is preferable because the current capacity can be further increased and the cycle characteristics can be dramatically improved.

More specifically,

[In the formula, a double line consisting of a solid line and a broken line is the same as described above. ]
Etc., and in particular,

Etc. These derivatives can also be preferably used.

The organic compound having a graphene fragment skeleton that can be used in the present invention or a derivative thereof is not limited to a neutral radical. It may be a salt composed of an anion derived from an organic compound having a graphene fragment skeleton or a derivative thereof and a metal cation. This is because these compounds also retain the quantum mechanical properties derived from degenerate orbitals derived from the graphene fragment skeleton.

For example, general formula (2):

[Wherein, R ¹ to R ³ and the double line composed of a solid line and a broken line are the same as described above. ]
A salt composed of an anion derived from an organic compound represented by formula (I) and a metal cation can also be used. The reason is as described above.

Examples of the anion derived from the organic compound represented by the general formula (2) include the general formula (2a):

[Wherein, R ¹ to R ³ and the double line composed of a solid line and a broken line are the same as described above. ]
As shown by these, monovalent anions are preferred.

As the metal cation, a monovalent cation is preferable, and examples thereof include lithium ions and potassium ions. In consideration of cycle characteristics, lithium ions are preferable.

In the present invention, neutral radicals and salts can be used as described above, but neutral radicals are preferred from the viewpoint of capacity and cycle characteristics.

In the present invention, a method for synthesizing an organic compound having a graphene fragment skeleton or a derivative thereof is not particularly limited.

For example, when synthesizing a compound in which R ¹ to R ³ are all alkyl groups having 1 to 6 carbon atoms, the compound is not limited to this, but the general formula (3):

[Wherein X is a halogen atom, and R ⁴ is an alkyl group having 1 to 6 carbon atoms]
Can be synthesized as starting materials.

In this compound, X is preferably a bromine atom. R ⁴ is preferably a tert-butyl group. That is, the preferred starting material is

It is.

Process (1)

[Wherein X ¹ is a halogen atom, and R ⁴ is the same or different and each is an alkyl group having 1 to 6 carbon atoms]

First, an organolithium compound is allowed to act on the compound represented by the general formula (3), and then a carbonate compound is allowed to act to obtain a compound represented by the general formula (4).

Examples of the organic lithium compound include methyl lithium, ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, pentyl lithium, hexyl lithium, cyclohexyl lithium, and phenyl lithium. Can be mentioned. Of these, tert-butyllithium and the like are preferable. Examples of the carbonate compound include diethyl carbonate, dimethyl carbonate, ethyl methyl carbonate, and ethylene carbonate.

In this case, the reaction atmosphere is not particularly limited, and specific examples include an air atmosphere and an inert gas atmosphere.

The amount of each substance used, reaction time, reaction temperature, etc. are not particularly limited. Conditions that are usually applied to the reaction can be used.

Here is the starting material

In the case of,

Is obtained.

Step (2)

[Wherein X ² is the same or different and each is a halogen atom; R ⁴ is the same as defined above]

Here, the hydroxyl group is reduced and eliminated. The method of reductive elimination is not particularly limited, and for example, a halogen (particularly iodine) and a reducing agent such as phosphinic acid can be used.

The amount of each substance used, solvent, reaction time, reaction temperature, etc. are not particularly limited. Conditions that are usually applied to the reaction can be used.

Next, the 2-position of each aryl group is halogenated. There is no particular limitation on the method in this case.

For example, in the case of iodination, it is preferable to react iodine with periodic acid, iodic acid or the like in the presence of acetic acid and sulfuric acid. Thereby, even an inert substrate can be iodinated.

Thereby, the compound represented by the general formula (5) is obtained.

Here is the starting material

In the case of,

Is obtained.

Process (3)

[Wherein X ² and R ⁴ are the same as defined above]

Here, the halogen atom at the 2-position of the aryl group is substituted with a carboxyl group. The method is not particularly limited. Examples thereof include a method using carbon monoxide and water in the presence of a palladium catalyst. Specifically, it is preferable to blow CO gas in a solvent in the presence of a palladium catalyst and then hydrolyze under alkaline conditions.

Examples of the palladium catalyst include metal palladium and palladium compounds known as synthesis catalysts for organic compounds (including polymer compounds). Specifically, Pd (PPh ₃ ) ₄ , PdCl ₂ (PPh ₃ ) ₂ , Pd (CH ₃ COO) ₂ , tris (dibenzylideneacetone) dipalladium (0), bis (dibenzylideneacetone) palladium (0) Bis (tri-t-butylphosphino) palladium (0) and the like. In this step, Pd (CH ₃ COO) ₂ or the like is preferable.

In the coupling step, a ligand capable of coordinating with a palladium atom, which is a central element of the palladium catalyst, can be used together with the catalyst, if necessary. Examples of the ligand include triphenylphosphine, tri-o-tolylphosphine, tri-m-tolylphosphine, tri-p-tolylphosphine, 2- (di-t-butylphosphino) biphenyl, 2- ( Dicyclohexylphosphino) biphenyl, 2- (dicyclohexylphosphino-2 ′, 6′-dimethoxy-1,1′-biphenyl (S-Phos), 2- (dicyclohexylphosphino-2 ′, 4 ′, 6′-tri -Isopropyl-1,1'-biphenyl (X-Phos), bis (2-diphenylphosphinophenyl) ether (DPEPhos) and the like.

The solvent is not particularly limited. For example, N, N-dimethylformamide, N, N-dimethylacetamide, hexamethylphosphoric triamide, tetrahydrofuran, 1,2-dimethoxyethane, 1,4-dioxane, benzene, toluene, xylene, ethanol, methanol, propanol, etc. Can be used.

There are no particular restrictions on the alkali used for the alkaline conditions. For example, it is preferable to use potassium hydroxide, sodium hydroxide, lithium hydroxide, or calcium hydroxide.

Thereby, the compound represented by the general formula (6) is obtained.

Here is the starting material

In the case of,

Is obtained.

Process (4)

[Wherein R ⁴ and a double line consisting of a solid line and a broken line are the same as above]

Here, after the halogenating agent is allowed to act, the Lewis acid catalyst is allowed to act. This reaction is known as the Friedel-Crafts reaction.

Examples of the halogenating agent include oxalyl chloride, thionyl chloride and the like, but oxalyl chloride is preferable.

Specific examples of the Lewis acid catalyst include metal or metalloid halides such as aluminum chloride, aluminum bromide, iron (III) chloride, iron (III) bromide, and titanium (IV) chloride. Among them, aluminum chloride is preferable.

Thereby, the compound represented by the general formula (7) is obtained.

Here is the starting material

In the case of,

[In the formula, the double line consisting of a solid line and a broken line is the same as above]
Is obtained.

Thereafter, the compound represented by the general formula (7) is neutralized and then reacted with tetrabutylammonium hydroxide (Bu ₄ NOH), whereby R ¹ to R ³ in the general formula (2a) are all carbon atoms. A tetrabutylammonium salt of an anion which is an alkyl group of 1 to 6 is obtained.

Further, by oxidizing the anion obtained by neutralizing the compound represented by the general formula (7) with an oxidizing agent (particularly chloranil), in the general formula (2), R ¹ to R ³ are all carbon atoms. Neutral radicals which are 1 to 6 alkyl groups are obtained.

Further, after neutralizing the tetrabutylammonium salt with an acid such as hydrochloric acid, a potassium compound (KOH or the like) or a lithium compound (LiOH.H ₂ O or the like) is allowed to act, thereby allowing R ¹ to R ¹ in general formula (2a). A potassium salt, a lithium salt, or the like of an anion in which R ³ is an alkyl group having 1 to 6 carbon atoms can be obtained.

Also, as a starting material, general formula (1 '):

[Wherein X ³ and X ⁴ are the same or different and each is a halogen atom; R ⁵ is an alkyl group having 1 to 6 carbon atoms. ]
A compound represented by

In the general formula (2), R ¹ to R ³ are all neutral radicals, and in the general formula (2a), R ¹ to R ³ are all Tetrabutylammonium salt, lithium salt, potassium salt and the like of an anion which is a halogen atom can also be obtained.

2. A positive electrode active material (also referred to simply as an active material) is a material that directly contributes to electrode reactions such as a charge reaction and a discharge reaction, and plays a central role in a battery system. In the present invention, the organic compound having a graphene fragment skeleton described above or a derivative thereof is used as the electrode active material. In addition, only 1 type may be used for the organic compound which has the graphene fragment skeleton mentioned above, or its derivative (s), and 2 or more types may be used together.

Further, as the electrode active material, only the organic compound having the graphene fragment skeleton described above or a derivative thereof may be used, or a conventionally known active material may be used in combination. However, from the viewpoint of obtaining a rare metal-free secondary battery and from the viewpoint of obtaining a secondary battery having a high capacity and excellent cycle characteristics, the organic compound having a graphene fragment skeleton or a derivative thereof is preferably used as a main component. It is preferable to contain an organic compound having a graphene fragment skeleton or a derivative thereof in an amount of 50% by mass or more, particularly 70% by mass or more, and more preferably 90% by mass or more. The reason why it is preferable to mainly contain an organic compound having a graphene fragment skeleton or a derivative thereof as a mass% is that a large number of electrons occupying degenerate orbitals derived from the graphene fragment skeleton of these molecules can be used for the redox reaction of the battery. Because.

In the present invention, it is more preferable to use a carbon material as the conductive material in addition to the organic compound having a graphene fragment skeleton described above or a derivative thereof. Although carbon materials are also used in conventional lithium ion batteries and the like as conductivity imparting materials, in the case of the present invention, metal powders, conductive polymers, etc. are not allowed to operate as batteries. It is thought that some kind of action is exerted.

Examples of the carbon material that can be used in the present invention include carbonaceous fine particles such as graphite, carbon black, and acetylene black; carbon fibers such as vapor grown carbon fiber (VGCF) and carbon nanotube. In the present invention, these carbon materials can be used alone or in combination of two or more. Of these, carbon fibers such as vapor grown carbon fibers (VGCF) and carbon nanotubes are preferable. The mixing ratio of the carbonaceous material in the electrode is not particularly limited, but may be, for example, 10 to 90% by mass.

In order to strengthen the connection between the constituent materials of the positive electrode, a binder (binder) can also be used. As this binder, polytetrafluoroethylene, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, styrene / butadiene copolymer rubber, polypropylene, polyethylene, polyimide And resin binders such as various polyurethanes. These resin binders can be used alone or in admixture of two or more. The ratio of the binder in the electrode is not particularly limited, but may be 5 to 30% by mass, for example.

In the present invention, as a positive electrode current collector, a current collector having a shape such as a foil, a semi-metal, a metal flat plate including a semiconductor, a mesh, or the like made of nickel, aluminum, copper, gold, silver, an aluminum alloy, stainless steel, carbon or the like. Can be used.

3. Organic Molecular Spin Battery The organic molecular spin battery of the present invention has the positive electrode of the present invention described above.

The counter electrode is provided to face the positive electrode, and corresponds to the negative electrode in the present invention. In the present invention, a conductor capable of depositing cations such as a lithium-laminated copper foil and a platinum plate; an electrode containing a negative electrode active material, and the like can be used. Of these, the negative electrode active material is not particularly limited as long as it is a material capable of occluding and releasing cations. Natural graphite, crystalline carbon such as graphitized carbon obtained by heat treatment of coal / petroleum pitch at high temperature, coal Conventionally known materials can be used as the negative electrode active material of the secondary battery, such as amorphous carbon and lithium alloy obtained by heat treatment of petroleum pitch coke, acetylene pitch coke and the like.

In the present invention, as a negative electrode current collector, a current collector having a shape such as a foil, a semi-metal, a metal flat plate including a semiconductor, a mesh, or the like made of nickel, aluminum, copper, gold, silver, an aluminum alloy, stainless steel, carbon or the like. Can be used.

In the present invention, a separator can be used for the purpose of separating the positive electrode and the negative electrode as in the conventional lithium ion secondary battery.

An electrolyte solution can be used to transport charge carriers between the positive electrode layer and the counter electrode. In general, as the electrolyte in the electrolytic solution, one having an ionic conductivity of 10 ⁻⁵ to 10 ⁻¹ S / cm at room temperature is more preferably used. As the electrolyte, for example, an electrolytic solution in which an electrolyte salt is dissolved in a solvent, a solid electrolyte made of a polymer compound containing the electrolyte salt, or the like can be used.

Examples of the electrolyte salt constituting the electrolytic solution 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 ( A lithium compound such as CF ₃ SO ₂ ) ₃ C or Li (C ₂ F ₅ SO ₂ ) ₃ C can be used.

Solvents for dissolving the electrolyte salt include, for example, ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, γ-butyrolactone, tetrahydrofuran, dioxolane, sulfolane, dimethylformamide, dimethylacetamide, N-methyl-2. -An organic solvent such as pyrrolidone can be used. These can be used alone or in combination of two or more.

Polymer compounds constituting the solid electrolyte include polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-ethylene copolymer, vinylidene fluoride-monofluoroethylene copolymer, and vinylidene fluoride. Vinylidene fluoride polymers such as trifluoroethylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer; acrylonitrile-methyl methacrylate copolymer , Acrylonitrile-methyl acrylate copolymer, acrylonitrile-ethyl methacrylate copolymer, acrylonitrile-ethyl acrylate copolymer, acrylonitrile-methacrylic acid copolymer, acrylonitrile-acrylic acid copolymer Coalescence, acrylonitrile - acrylonitrile polymers such as vinyl acetate copolymer; polyethylene oxide, ethylene oxide - propylene oxide copolymers, these acrylate bodies, polymer and the like of the methacrylate products 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.

In the present invention, the shape of the battery is not particularly limited, and may be a cylindrical shape, a square shape, a coin shape, a sheet shape, or the like, which is performed in a conventional battery. Further, the exterior method is not particularly limited, and it can be performed by a metal case, a mold resin, an aluminum laminate film, or the like. A conventionally known method can also be used for taking out the lead from the electrode.

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

[Comparative Example 1]
2,5,8-tri-tert-butyl-6-oxophenalenoxyl (6OPO):

Was synthesized according to a method described in a known document (Non-patent Document 1).

[Reference Example 1: (t-Bu) ₃ TOT Bu ₄ N ⁺ salt]
General formula (2a):

The tetrabutylammonium salt of an anion represented by (Bu ₄ N ⁺ salt of (t-Bu) ₃ TOT) was synthesized as follows.

Process (1)
4-tert-butylbromobenzene:

Next, diethyl carbonate is allowed to act after tert-butyllithium is allowed to act,

Got.

Specifically, 4-tert-butylbromobenzene (14 mL, 85.3 mmol) was placed in a 1-L Schlenk tube equipped with a 200-mL dropping funnel and dissolved in tetrahydrofuran (400 mL). The mixture was cooled in a dry ice-ethanol bath and stirred for 1 hour. Using a dropping funnel, tert-butyllithium (1.48 M pentane solution, 115 mL, 170.7 mmol) was added dropwise. Thereafter, the temperature was raised to −78 ° C., followed by stirring for 1 hour. The reaction solution was cooled again, and diethyl carbonate (3.10 mL, 25.6 mmol) was added dropwise. After dropping, the temperature was raised and the mixture was stirred for 4 hours. Water (150 mL) was added to the reaction solution, followed by extraction with ethyl acetate, drying over anhydrous sodium sulfate, filtration and concentration under reduced pressure. The crude product was washed with hexane on the Kiriyama funnel to obtain a triphenylmethanol derivative (10.3 g, 94%) as a white solid.

Step (2)
Next, the hydroxyl group in the compound obtained in the step (1) was reduced and eliminated using iodine (I ₂ ) and phosphinic acid. The aryl group was iodinated with iodine (I ₂ ) in the presence of periodic acid and phosphinic acid. as a result,

Got.

Specifically, a 1-L eggplant-shaped flask was charged with triphenylmethanol derivative (12.0 g, 28.0 mmol), acetic acid (400 mL), iodine (7.11 g, 28.0 mmol), and 50% phosphine. Acid (30 mL) was added and a reflux condenser was attached and heated at 60 ° C. for 3 hours. After allowing to cool, water was added, and the resulting white solid was collected by filtration with a Kiriyama funnel to synthesize a triphenylmethane derivative.

Triphenylmethane derivative (5.40 g, 13.1 mmol), acetic acid (50 mL), distilled water (10 mL), periodic acid dihydrate (23.9 g, 105 mmol), iodine (13. 1 g, 52.3 mmol) and concentrated sulfuric acid (1.50 mL) were placed in an eggplant flask and heated to reflux at 110 ° C. After 15 hours, the mixture was allowed to cool and a saturated aqueous sodium hydrogen sulfite solution was added, followed by extraction with ethyl acetate, drying over anhydrous sodium sulfate, filtration and concentration. The crude product was dissolved in methylene chloride and subjected to column chromatography to obtain a tri (iodophenyl) methane derivative (5.96 g, 56%) as a white solid.

Process (3)
Next, under alkaline conditions, carbon monoxide (CO) gas was blown in the presence of Pd (CH ₃ COO) ₂ in N, N-dimethylformamide as a solvent, followed by hydrolysis. as a result,

Got.

Specifically, a tri- (iodophenyl) methane derivative (4.00 g, 5.06 mmol), 1,3-diphenylphosphinopropane (313 mg, 0.759 mmol), palladium acetate was added to a 100-mL eggplant flask. (II) (170 mg, 0.759 mmol), N, N-dimethylformamide (40 mL), methanol (4 mL), and triethylamine (4.24 mL, 30.4 mmol) were added. The mixture was stirred for 4 days at 80 ° C. in a carbon monoxide gas atmosphere. After completion of the reaction, the mixture was cooled to room temperature, saturated aqueous sodium chloride solution was added, and the mixture was extracted with ethyl acetate. The organic layer was washed with a saturated aqueous sodium chloride solution, dried over anhydrous sodium sulfate, filtered and concentrated. The crude product was dissolved in methylene chloride and subjected to column chromatography to obtain a triester derivative (1.35 g, 45%) as a pale yellow foamy solid.

A triester derivative (900 mg, 1.53 mmol) is placed in a 50-mL eggplant flask, and ethanol (35 mL) and potassium hydroxide (4.3 g, 76.7 mmol) are dissolved in water (7 mL). The aqueous solution was added and heated to reflux for 3 hours. After allowing to cool, 2 mol / L hydrochloric acid was added, and the mixture was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated to obtain a tricarboxylic acid derivative (820 mg) as a pale yellow solid.

Process (4)
Furthermore, after acting on oxalyl chloride, acting on aluminum chloride (AlCl ₃ ) as a Lewis acid catalyst,

[In the formula, the double line consisting of a solid line and a broken line is the same as above]
Got.

Specifically, a tricarboxylic acid derivative (400 mg, 0.734 mmol) was placed in a 100-L eggplant flask, oxalyl chloride (10.0 mL) was added, and the mixture was heated to reflux. After 2 hours, excess oxalyl chloride was distilled off under reduced pressure. The residue was dissolved in methylene chloride (12 mL), and aluminum chloride (979 mg, 7.34 mmol) was added and stirred at low temperature. After 2 hours, methylene chloride was distilled off under vacuum, potassium carbonate (8 g) was added to the blue residue and mixed, and distilled water was further suspended while cooling with water. The mixture was extracted with ethyl acetate, and the organic layer was washed with a saturated aqueous sodium chloride solution. After drying over anhydrous sodium sulfate, filtration and concentration, potassium salt of (t-Bu) ₃ TOT anion (563 mg) was obtained as a blue solid.

Process (5)
After this, neutralize the resulting compound,

In addition, by reacting tetrabutylammonium hydroxide (Bu ₄ NOH), a Bu ₄ N ⁺ salt of (t-Bu) ₃ TOT anion was obtained.

Specifically, this anion potassium salt (563 mg) was placed in a 20-mL eggplant flask, suspended in 2 mol / L hydrochloric acid (20 mL), and heated and stirred for 2 hours. After allowing to cool, the solid was collected by filtration with a Kiriyama funnel and washed with 2 mol / L hydrochloric acid to obtain a hydroxy diketone derivative (294 mg).

Subsequently, a hydroxy diketone derivative (497 mg, 1.01 mmol) was placed in a 30-mL eggplant flask and suspended in an aqueous solution obtained by diluting an aqueous tetrabutylammonium hydroxide solution (2 mL) with water (5 mL). After stirring for 30 minutes, the blue solid was filtered with a Kiriyama funnel and then washed with distilled water. By vacuum drying, a Bu ₄ N ⁺ salt (536 mg, 57%) of t-Bu) ₃ TOT anion was obtained as a blue solid.
Bu ₄ N ⁺ salt of (t-Bu) ₃ TOT anion: blue blocks containing triglyme and water molecules as crystal solvents; mp: 203-204 ° C; ¹ H NMR (270 MHz, DMSO-d ₆ ): δ 0.93 (t , J = 7.3 Hz, 12H), 1.30 (m, 8H), 1.49 (s, 27H), 1.49-1.61 (m, 8H), 3.12-3.18 (m, 8H), 8.81 (s, 6H); Analysis ( calcd, found for C ₅₀ H ₆₉ NO ₃ (C ₈ H ₁₈ O ₄ ) _0.5 (H ₂ O)): C (77.28, 77.20), H (9.61, 9.35), N (1.67, 1.84).

[Example 1: (t-Bu) ₃ TOT]
By oxidizing the TOT anion obtained in the middle of Synthesis Example 1 with chloranil,

A neutral radical ((t-Bu) ₃ TOT) represented by

Specifically, TOT anion (100 mg, 0.137 mmol) and chloranil (33.6 g, 0.137 mmol) were placed in a 30-mL eggplant flask and dissolved in 1,2-dimethoxyethane (5 mL). . After stirring at room temperature for 20 minutes, the solvent was distilled off under vacuum. The crude product was dissolved in chloroform (80 mL) and subjected to column chromatography to obtain a neutral radical (51.9 mg, 77%) as a brown solid.
(t-Bu) ₃ TOT neutral radical: black needles containing water molecule as a crystal solvent; dp> 300 ° C; Analysis (calcd, found for C ₃₄ H ₃₃ O ₃ (H ₂ O) _0.15 ): C (82.95, 82.75 ), H (6.82, 6.64), N (0.00, 0.00).

[Example 2: K ⁺ salt of (t-Bu) ₃ TOT anion]
After neutralizing the Bu ₄ N ⁺ salt of the (t-Bu) ₃ TOT anion obtained in Synthesis Example 1 with 2M HCl, KOH is allowed to act on the target compound ((t-Bu) ₃ TOT anion K). ⁺ Salt).

Specifically, an anion Bu ₄ N ⁺ salt (43 mg, 0.09 mmol) was placed in a 20-mL eggplant flask and dissolved in ethanol (5 mL). Potassium carbonate (61 mg, 0.44 mmol) was added and stirred. After 1.5 hours, water (1 mL) was added and the resulting precipitate was collected by filtration with a Kiriyama funnel and dried in vacuo to give an anion K ⁺ salt as a blue solid.
K ⁺ salt of (t-Bu) ₃ TOTanion: blue powder containing water; dp> 300 ° C; Analysis (calcd, found for C ₃₄ H ₃₃ O ₃ K (H ₂ O) ₃ ): C (70.07, 69.90), H (6.75, 6.72), N (0.00, 0.00).

[Example 3: Li ⁺ salt of (t-Bu) ₃ TOT anion]
After neutralizing the Bu ₄ N ⁺ salt of the (t-Bu) ₃ TOT anion obtained in Synthesis Example 1 with 2M HCl, the target product ((t-Bu) ₃ is obtained by reacting with LiOH · H ₂ O. Li ⁺ salt of TOT anion).

Specifically, an anion Bu ₄ N ⁺ salt (58 mg, 0.12 mmol) was placed in a 20-mL eggplant flask and dissolved in ethanol (5 mL). Lithium hydroxide monohydrate (50 mg, 1.2 mmol) was added and stirred. After 2 hours, water (10 mL) was added and the resulting precipitate was collected by filtration with a Kiriyama funnel and dried in vacuo to give an anion Li ⁺ salt as a blue solid.
Li ⁺ salt of (t-Bu) ₃ TOTanion: blue powder containing water; dp> 300 ° C; Analysis (calcd, found for C ₃₄ H ₃₃ O ₃ Li (H ₂ O) ₂ ): C (76.67, 76.61), H (7.00, 6.85), N (0.00, 0.00).

[Reference Example 2: Bu ₄ N ⁺ salt of Br ₃ TOT anion]
As a starting material,

Except for using this, the same method as in Synthesis Example 1,

As a result, a Bu ₄ N ⁺ salt of the anion represented by (Br ₃ TOT anion) was obtained.

Specifically, 2-iodo-5-bromotoluene (9.0 mL, 63.7 mmol) was placed in a 1-L Schlenk tube and dissolved in tetrahydrofuran (30 mL). After cooling to −78 ° C., n-butyl lithium (1.6 μM hexane solution, 40 μmL, 64 μmmol) was added dropwise and stirred for 1 hour. Thereafter, diethyl carbonate (2.3 mL, 19.1 mmol) was added dropwise and stirred for 1.5 hours. Water (100 mL) was added to the reaction solution, followed by extraction with ethyl acetate, and the organic layer was washed with saturated brine. After drying over sodium sulfate, it was filtered and concentrated. The crude product was dissolved in methylene chloride and subjected to column chromatography to obtain a triphenylmethanol derivative (4.52 g, 44%) as a white powder.

A 1-L Schlenk tube was charged with triphenylmethanol derivative (4.32 g, 8.38 mmol), dissolved in trifluoroacetic acid (300 mL), and cooled in an ice bath. Sodium borohydride (3.17 g, 83.8 mmol) was added, and the mixture was warmed to room temperature and stirred for 30 minutes. Trifluoroacetic acid was distilled off, and a saturated aqueous sodium hydrogen carbonate solution was added for neutralization. Extraction with ethyl acetate was performed, and the organic layer was washed with saturated brine, dried over sodium sulfate, filtered, and concentrated to obtain a triphenylmethane derivative (4.10 g, 98%) as a white powder. .

In a 1-L eggplant flask, 2-methyl-2-propanol (300 mL), water (300 mL), a triphenylmethane derivative (5.80 g, 11.1 mmol), potassium permanganate (52.6 g, 333 mmol) was added and heated to reflux. After 40 hours, it was cooled to room temperature, insoluble material was filtered off and washed with ethyl acetate. To the filtrate was added 2 mol / L hydrochloric acid and extracted with ethyl acetate. The organic layer was washed with saturated brine, dried over sodium sulfate, filtered and concentrated to give a tricarboxylic acid derivative (6.00 g, 89%) was obtained as a white powder.

A tricarboxylic acid derivative (2.80 g, 4.57 mmol) was added to a 200-mL eggplant flask, dissolved in concentrated sulfuric acid (60 mL), and heated and stirred for 1 hour. After allowing to cool, the deposited precipitate was collected by filtration and washed with water, methylene chloride and acetone to obtain a hydroxy diketone body (1.51 g, 58%) as a purple powder.

A 100-mL eggplant flask was charged with hydroxy diketone (406 mg, 0.73 mmol) and dissolved in acetone (50 mL). Tetrabutylammonium hydroxide aqueous solution (2.2 mL) was added and stirred. After 1 hour, the solvent was distilled off under reduced pressure, and the residue was washed with water to obtain an anion Bu ₄ N ⁺ salt (507 mg, 87%).
Bu ₄ N ⁺ salt of Br ₃ TOT anion: blue crystals containing water molecule as a crystal solvent; dp: 191-192 ° C; ¹ H NMR (400 MHz, DMSO-d ₆ ): δ 0.93 (t, J = 7.3 Hz 12H), 1.25-1.35 (m, 8H), 1.52-1.62 (m, 8H), 3.15 (t, J = 8.5 Hz, 8H), 8.59 (s, 6H); Analysis (calcd, found for C ₃₈ H ₄₂ Br ₃ O ₃ N (H ₂ O) _0.4 ): C (56.51, 56.53), H (5.34, 5.27), N (1.73, 1.83).

[Example 4: Br ₃ TOT]
As a starting material,

In the same manner as in Synthesis Examples 1 and 2, except that

In to obtain a neutral radicals _(Br 3 TOT) shown.

Specifically, an anion Bu ₄ N ⁺ salt (503 mg, 0.63 mmol) was placed in a 100-mL eggplant flask and dissolved in methylene chloride (40 mL). 2,3-Dichloro-5,6-dicyanobenzoquinone (223 mg, 0.95 mmol) was added and stirred at room temperature. After 1 hour, the resulting precipitate was filtered with a Kiriyama funnel to obtain neutral radicals (351 mg, ˜100%).
Br ₃ TOT neutral radical: black blocks; dp: 268 ° C; Analysis (calcd, found for C ₂₂ H ₆ Br ₃ O ₃ ): C (47.35, 47.04), H (1.08, 1.30), N (0.00, 0.00) .

[Test Example 1: Energy level diagram]
In order to obtain knowledge about the electronic structure that is the key to the molecular design, the quantum chemistry calculation for 6OPO of Comparative Example 1, (t-Bu) ₃ TOT of Example 1 and Br ₃ TOT of Example 4 is as follows. Went.

Quantum chemistry calculations were performed using GAUSSIAN 03 at the ROB3LYP / 6-31G (d, p) level using the molecular structure optimized at the UB3LYP / 6-31G (d, p) level. The results are shown in FIG.

As a result, 6OPO had an energy gap between SOMO and LUMO of 0.94 eV. Further, (t-Bu) ₃ TOT and Br ₃ TOT both had SOMO and two degenerate LUMOs, and the energy gaps were 0.82 eV and 0.56 eV, respectively. The frontier molecular orbitals of Br ₃ TOT existed at lower positions than 6OPO and (t-Bu) ₃ TOT.

[Test Example 2: Redox behavior (CV curve)]
For _{_{(t-Bu) 3 Bu 4}} N + salt and _Bu 4 ^{N +} salt of _Br 3 TOT anion of Reference Example 2 TOT of Reference Example 1 was measured redox behavior as follows.

At 290 K (17 ° C.), 0.1 M of Bu ₄ NClO ₄ was used as a supporting electrolyte in 1 × 10 ⁻³ M THF solution of Bu ₄ N ⁺ salt of (t-Bu) ₃ TOT of Reference Example 1. I put it in. Thereafter, measurement was performed using a reference electrode of Ag / 10 mM AgNO ₃ at room temperature and under an argon atmosphere using a gold working electrode having a diameter of 1.6 mm and a counter electrode of platinum wire. The results were standardized with ferrocene / ferrocenium.

For Br ₃ TOT measurements _Bu 4 ^{N +} salt of the anion, but using THF solution of 3 × ^{10 -3} M of _Bu 4 ^{N +} salt of _Br 3 TOT anion of Reference Example 2 were the same as described above.

The results are shown in FIG. Note that Reference Example 1 is shown above and Reference Example 2 is shown below.

In Reference Example 1, in addition to −0.40 V, three redox waves having a small potential difference between −2.0 and −2.6 V were reversibly observed. On the other hand, in Reference Example 2, an electrochemically irreversible wave in the vicinity of 0V and a redox wave between -2.0 and -3.05V were observed. This suggests that it has four levels of redox ability.

[Comparative Example 2: Battery using 6OPO]
6OPO, polytetrafluoroethylene, and VGCF of Comparative Example 1 were weighed so as to have a mass ratio of 10:10:80, and kneaded while being uniformly mixed. This mixture was pressure-molded to obtain a thin plate having a thickness of about 150 μm. This was dried in a vacuum at 80 ° C. for 1 hour, and then punched into a circle having a diameter of 12 mm to obtain a positive electrode layer containing 6OPO.

Next, the obtained positive electrode layer was impregnated with 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 M LiPF ₆ electrolyte salt was used. This positive electrode was placed on a positive electrode current collector constituting a coin-type battery, and a separator made of a polypropylene porous film that was also impregnated with an electrolytic solution was laminated thereon, and further, a lithium-bonded copper foil serving as a negative electrode was laminated. . Thereafter, an aluminum exterior (made by Hohsen) of a coin-type battery is overlaid with an insulating packing disposed around it, and pressurized by a caulking machine, and a sealed coin type using 6OPO as a positive electrode active material and metallic lithium as a negative electrode active material. A battery was produced.

[Example 5: Battery (1) using (t-Bu) ₃ TOT]
As a cathode active material, in the same manner as Comparative Example 2 except for using _(t-Bu) 3 TOT of 6OPO rather Example 1, as a cathode active material _(t-Bu) 3 TOT, metal as an anode active material A sealed coin-type battery using lithium was produced.

[Example 6: Battery using (t-Bu) ₃ TOT (2)]
The (t-Bu) ₃ TOT, polytetrafluoroethylene, and acetylene black of Example 1 were measured so as to have a mass ratio of 10:30:60, and kneaded while being uniformly mixed. This mixture was pressure-molded to obtain a thin plate having a thickness of about 150 μm. This was dried in a vacuum at 80 ° C. for 1 hour, and then punched into a circle having a diameter of 12 mm to obtain a positive electrode layer containing (t-Bu) ₃ TOT.

Next, the obtained positive electrode layer was impregnated with an electrolytic solution, and the electrolytic solution was infiltrated into voids in the electrode. As the electrolytic solution, a triethylene glycol dimethyl ether solution containing 1.0 M LiN (SO ₂ CF ₃ ) ₂ electrolyte salt was used. This positive electrode was placed on a positive electrode current collector constituting a coin-type battery, and a separator made of a polypropylene porous film that was also impregnated with an electrolytic solution was laminated thereon, and further, a lithium-bonded copper foil serving as a negative electrode was laminated. . After that, the outer casing of the coin-type battery (made by Hohsen) is stacked with insulating packing around it, and it is pressurized by a caulking machine, using (t-Bu) ₃ TOT as the positive electrode active material and metallic lithium as the negative electrode active material. A sealed coin-type battery was manufactured.

[Example 7: Battery using K ⁺ salt of (t-Bu) ₃ TOT anion]
As a cathode active material, similarly except for using _(t-Bu) of 3 TOT anionic ^{K +} salt 6OPO rather Example 2 and Comparative Example 2, as a positive electrode active material _(t-Bu) 3 TOT anion A sealed coin-type battery using K ⁺ salt and lithium metal as a negative electrode active material was prepared.

[Example 8: Battery using Li ⁺ salt of (t-Bu) ₃ TOT anion]
As a cathode active material, similarly except for using _(t-Bu) of 3 TOT anion Li ⁺ salt of the 6OPO rather Example 3 and Comparative Example 2, as a positive electrode active material _(t-Bu) 3 TOT anion A sealed coin-type battery using Li ⁺ salt and metallic lithium as a negative electrode active material was prepared.

[Example 9: Battery using Br ₃ TOT]
The Br ₃ TOT, the polyvinylidene fluoride and acetylene black of Example 4 were weighed to a mass ratio of 10:10:80 and kneaded with uniform mixing. This mixture was pressure-molded to obtain a thin plate having a thickness of about 150 μm. This was dried in a vacuum at 100 ° C. for 12 hours, and then punched into a circle having a diameter of 12 mm to obtain a positive electrode layer containing Br ₃ TOT.

Next, the obtained positive electrode layer was impregnated with an electrolytic solution, and the electrolytic solution was infiltrated into voids in the electrode. As the electrolytic solution, an ethylene carbonate / ethyl methyl carbonate mixed solution (mixing volume ratio 3: 7) containing 1.0 M LiPF ₆ electrolyte salt was used. This positive electrode was placed on a positive electrode current collector constituting a coin-type battery, and a separator made of a polypropylene porous film that was also impregnated with an electrolytic solution was laminated thereon, and further, a lithium-bonded copper foil serving as a negative electrode was laminated. . Thereafter, an aluminum exterior (made by Hohsen) of a coin-type battery is stacked with an insulating packing disposed around it, and pressurized by a caulking machine, and a sealed type using Br ₃ TOT as a positive electrode active material and metallic lithium as a negative electrode active material. A coin-type battery was produced.

[Test Example 3: Charging / discharging characteristics and cycle characteristics]
The charge / discharge characteristics and cycle characteristics of the coin type batteries of Comparative Example 2 and Examples 5 to 9 were measured as follows.

Comparative Example 2
The coin-type battery of Comparative Example 2 was charged until the voltage became 4.0 V at 1 C, and then discharged to 2.0 V at 1 C. Thereafter, charging / discharging between 2.0 and 4.0 V was similarly repeated 100 cycles. The results are shown in FIGS. 3a, 4 and 5.

As a result, the initial discharge capacity was 152 Ah / kg, which was close to the theoretical value of 147 Ah / kg.

In the charging process after the second cycle, the potential at which the behavior changed first decreased to 3.0 V, and no stepwise behavior was shown. On the other hand, in the discharge process, the behavior changed stepwise at three locations of 3.5 V, 2.7 V, and 2.1 V (average potential: 2.9 V).

This behavior was the same even when the charge / discharge conditions were not 2 ° C but 2 ° C or 3 ° C.

Also, the discharge capacity after 100 cycles was reduced to 33 Ah / kg, and the cycle characteristics were only 22%. When the number of cycles was measured up to 500 cycles, the capacity further decreased.

Example 5
The same as in the case of the coin-type battery of Comparative Example 2, except that the coin-type battery of Example 5 was used and the charge / discharge conditions were set to be 1.4 to 3.8 V at 0.3 C. I made it. The result is shown in FIG.

The initial capacity (311 Ah / kg) and the capacity of the second cycle (169 Ah / kg) are remarkably superior to those of the coin-type battery of Comparative Example 2 and the conventional lithium ion battery using LiCoO ₂ , and are approximately twice as much. Met. The initial capacity was much larger than the theoretical value (220 Ah / kg).

Further, since the discharge capacity after 100 cycles was 73 Ah / kg, the cycle characteristic was 43%, which was greatly improved as compared with Comparative Example 2.

Example 6
The same as in the case of the coin-type battery of Comparative Example 2, except that the coin-type battery of Example 6 was used and the charge / discharge conditions were between 1.4 and 3.6 V at 0.2 C. I made it. As a result, both initial capacity and cycle characteristics were lower than in Example 5, suggesting that VGCF is excellent as a conductive material.

Example 7
The same as in the case of the coin-type battery of Comparative Example 2, except that the coin-type battery of Example 7 was used, and the charge / discharge conditions were 0.3 C to charge / discharge between 1.2 and 4.0 V. I made it. As a result, both initial capacity and cycle characteristics were lower than in Example 8 described later, suggesting that lithium ions are superior as cations.

Example 8
The same as in the case of the coin-type battery of Comparative Example 2, except that the coin-type battery of Example 8 was used and the charge / discharge conditions were between 1.2 and 4.0 V at 0.1 C. I made it. As a result, both initial capacity and cycle characteristics were lower than in Example 5, suggesting that neutral radicals are superior.

Example 9
In the case of the coin-type battery of Comparative Example 2 except that the coin-type battery of Example 9 was used and the charge / discharge conditions were 1 C or 2 C and charge / discharge between 1.4 and 4.0 V was performed. The same was done. The results are shown in FIG.

As a result, the initial capacity when charging / discharging at 1 C was 225 Ah / kg, and the initial capacity when charging / discharging at 2C was 208 Ah / kg, a value close to the theoretical value (192 Ah / kg).

The discharge capacity after 100 cycles is 159 Ah / kg at 1 C, so the cycle characteristic is 71%, and the cycle characteristic is 177 Ah / kg at 2 C, so the cycle characteristic is 85%. In comparison, capacity and cycle characteristics (particularly cycle characteristics) were dramatically improved.

Claims

A positive electrode active material for a secondary battery comprising an organic compound having a graphene fragment skeleton or a derivative thereof, wherein the organic compound having a graphene fragment skeleton or a derivative thereof is
General formula (2):

[Wherein, R 1 to R 3 are the same or different and each represents an alkyl group having 1 to 6 carbon atoms, a halogen atom; a double line composed of a solid line and a broken line is a single bond or a double bond. ]
A salt composed of an anion derived from an organic compound represented by formula (I) and a metal cation, and general formula (2 ′):

[Wherein R 1 to R 3 are the same or different and each is a halogen atom; a double line composed of a solid line and a broken line is a single bond or a double bond. ]
The positive electrode active material for secondary batteries containing at least 1 sort (s) chosen from the group which consists of the organic compound shown by these, or its derivative (s).
The positive electrode active material for a secondary battery according to claim 1, wherein the organic compound having a graphene fragment skeleton or a derivative thereof has a degenerate frontier molecular orbital.
The secondary compound according to claim 1 or 2, wherein the organic compound having a graphene fragment skeleton or a derivative thereof contains a salt composed of an anion derived from the organic compound represented by the general formula (2) and a metal cation. Positive electrode active material for batteries.
The positive electrode active material for a secondary battery according to any one of claims 1 to 3, wherein, in the general formula (2), R 1 to R 3 are the same or different and all are halogen atoms.
The positive electrode active material for a secondary battery according to claim 1, wherein the organic compound having a graphene fragment skeleton or a derivative thereof contains the organic compound represented by the general formula (2 ′) or a derivative thereof.
The positive electrode active material for a secondary battery according to any one of claims 1 to 5, wherein in the general formulas (2) and (2 '), R 1 to R 3 are all bromine atoms.
A secondary battery positive electrode comprising the secondary battery positive electrode active material according to any one of claims 1 to 4.
Furthermore, the positive electrode for secondary batteries of Claim 7 containing electroconductive carbon fiber.
A positive electrode for a secondary battery, comprising a positive electrode active material for a secondary battery containing an organic compound having a graphene fragment skeleton or a derivative thereof, and conductive carbon fiber.
The positive electrode for a secondary battery according to claim 9, wherein the organic compound having a graphene fragment skeleton or a derivative thereof has a degenerate frontier molecular orbital.
An organic molecular spin battery comprising the positive electrode according to any one of claims 7 to 10.
Furthermore, the organic molecular spin battery of Claim 10 which has an electrolyte solution containing a lithium compound.