Lithium-ion battery

Abstract

To provide a material capable of being used in a wide temperature range.SOLUTION: A graphene compound has graphene or graphene oxide and a substituted or unsubstituted chain group, where the chain group has two or more ether linkages and the graphene or graphene oxide and the chain group are linked via a Si atom. A graphene compound manufacturing method includes: a first step of stirring graphene oxide and a base under a nitrogen air flow; and a second step of reducing a temperature to a room temperature after the first step, introducing a sililation reagent containing a group having two or more ether linkages, and performing stirring, the base being butylamine, pentylamine, hexylamine, diethylamine, dipropylamine, dibutyl amine, triethylamine, tripropylamine, or pyridine.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] One aspect of the present invention relates to a graphene compound.

[0002] Note that one embodiment of the present invention is not limited to the above technical fields. The technical field of one aspect relates to an article, a method, or a manufacturing method. One aspect of the present invention is a process, machine, manufacture, or composition. Therefore, the invention disclosed herein more specifically relates to The technical field of one embodiment of the present invention is a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, Examples include their driving methods and their manufacturing methods. [Background technology]

[0003] In recent years, various storage batteries such as lithium-ion batteries, lithium-ion capacitors, and air batteries have become available. The development of energy storage devices is being actively pursued. Ion storage batteries are used in mobile phones, smartphones, laptops, and other portable devices. Information terminals, portable music players, digital cameras, and other electronic devices, as well as medical equipment and Hybrid electric vehicle (HEV), electric vehicle (EV), or plug-in hybrid vehicle (PHEV) Demand is rapidly expanding with the development of the semiconductor industry, including next-generation clean energy vehicles such as As a rechargeable energy source, it has become indispensable in today's information society. do.

[0004] However, lithium-ion batteries generally have a high energy density, and the electrolyte can ignite at high temperatures. The organic solvents used may cause damage to the battery, which may cause the protection circuit that controls charging and discharging to malfunction. Damage to the cells may result in heat generation, fire, or explosion. Similar accidents have been reported.

[0005] One way to reduce this risk is to use all-solid-state batteries, which replace the liquid electrolyte with a solid electrolyte. For example, a lithium ion conductive polymer electrolyte is being used as a solid electrolyte. Storage batteries using this technology are being researched.

[0006] However, even lithium-ion batteries that use polymer electrolytes can be depleted when the battery temperature drops. The ionic conductivity may be significantly reduced, and the battery characteristics may be significantly impaired. Polyethylene oxide (P) is a polymer that can be used in lithium-ion batteries. EO) are known (Patent Documents 1 to 3), but when used at low temperatures, they have poor ionic conductivity. In the first place, the melting point of PEO is around 60°C, and once melted, In such cases, there is a danger of short-circuiting between the electrodes, and therefore the usable temperature range is narrow. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2001-319692 [Patent Document 2] Japanese Patent Application Publication No. 05-314995 [Patent Document 3] Japanese Patent Application Publication No. 05-314965 Summary of the Invention [Problem to be solved by the invention]

[0008] The basic performance required for solid electrolytes in all-solid-state batteries is the ability to transfer charge. The high conductivity of the positive and negative electrodes prevents short circuits. The main reason is that electron conductivity is low due to the

[0009] Since batteries are widely used in various environments, it is necessary to develop practical all-solid-state lithium-ion batteries. To achieve this, a solid electrolyte that can demonstrate the basic performance described above even at high temperatures is required. High quality is required, i.e., a solid electrolyte that can withstand high temperature environments is required. For example, a structure that exhibits the performance of a solid electrolyte such as polyethylene oxide (PEO) Therefore, a material that has excellent heat resistance while maintaining the required structure is required.

[0010] In recent years, there has been a surge in the development of electronic devices that can be deformed. In order to realize an electronic device having the above structure, the components used in the electronic device must also be deformed. The housing and display unit of the electronic device must be flexible. However, the storage batteries installed in such electrical equipment are also required to be flexible.

[0011] In order to realize a flexible solid storage battery, each member used in the solid storage battery must also be flexible. Therefore, the solid electrolyte must also be flexible. In addition to polymer-based solid electrolytes such as PEO, ceramic solid electrolytes have also been widely studied. Ceramic solid electrolytes have a higher ionic conductivity than polymer solid electrolytes. However, ceramic solid electrolytes tend to be fragile and tend to have poor electrical conductivity. Since it is difficult to make contact with the electrolyte, flexibility cannot be expected.

[0012] In view of the above, one aspect of the present invention is to provide a material to be used for a solid electrolyte of a solid storage battery. Another objective is to provide a material that can be used over a wide temperature range. Another objective is to provide a material that can withstand shape changes. Another object of the present invention is to provide a chemically modified graphene compound. One of the objects is to provide a new graphene compound.

[0013] Another embodiment of the present invention is a storage battery that can change its shape, that is, a flexible storage battery. Another object of the present invention is to provide a storage battery having high performance. It is also an object of the present invention to provide a novel flexible storage battery using the same.

[0014] The description of these problems does not preclude the existence of other problems. It is not necessary for the present invention to solve all of these problems. The above will be made clear from the description, drawings, claims, etc. It is possible to extract other issues from the descriptions in the patent, claims, etc. [Means for solving the problem]

[0015] In view of the above, one embodiment of the present invention is a method for manufacturing a substituted or unsubstituted graphene or graphene oxide film. and a chain group having two or more ether bonds, The graphene and the chain group are bonded via Si atoms, making it a graphene compound. Another embodiment of the present invention is a method for producing a substituted or unsubstituted graphene or graphene oxide. and a chain group having four or more ether bonds, and The graphene compound is a graphene compound in which the graphene oxide and the chain group are bonded via Si atoms. Another embodiment of the present invention is a method for producing a substituted or unsubstituted graphene or graphene oxide. and a substituted chain group, the chain group having 2 to 20 ether bonds, The graphene or graphene oxide and the chain group are bonded via Si atoms. It is a compound.

[0016] Another embodiment of the present invention is a graphene compound having a structure represented by the following formula (200): It is a thing.

[0017] [ka]

[0018] In formula (200), GO represents graphene or graphene oxide, and R represents It represents a substituted or unsubstituted chain group having at least two ether bonds.

[0019] Another embodiment of the present invention is a graphene compound having a structure represented by the following formula (201): It is a thing.

[0020] [ka]

[0021] In the formula (201), GO represents graphene or graphene oxide.

[0022] Another embodiment of the present invention is a graphene compound having a structure represented by the following formula (202): It is a thing.

[0023] [ka]

[0024] In the formula (202), GO represents graphene or graphene oxide.

[0025] Also, a lithium battery having the above-mentioned graphene compound, an outer casing, a positive electrode current collector, and a negative electrode current collector is provided. A lithium-ion battery is also an aspect of the present invention.

[0026] Another embodiment of the present invention is a first method for stirring graphene oxide and a base under a nitrogen gas flow. After the first step, the temperature is lowered to room temperature, and a silyl group having two or more ether bonds is formed. and a second step of introducing and stirring an alkylating agent, and the base is selected from the group consisting of butylamine, pentylamine, amine, hexylamine, diethylamine, dipropylamine, dibutylamine, triethylamine A method for producing a graphene compound, wherein the compound is an amine, tripropylamine, or pyridine. be.

[0027] In another embodiment of the present invention, graphene oxide and butylamine are stirred under a nitrogen gas flow. After the first step, the temperature is lowered to room temperature, and methoxytriethyleneoxypropyl and a second step of adding trichlorosilane dropwise and stirring the mixture. It is a method.

[0028] In another embodiment of the present invention, graphene oxide and butylamine are stirred under a nitrogen gas flow. After the first step, the temperature is lowered to room temperature, and 2-[methoxy(polyethylene oxide)] a second step of adding dropwise 6-9-propyltrichlorosilane and stirring the mixture; A method for producing phene compounds. [Effects of the Invention]

[0029] According to one embodiment of the present invention, a material for use in a solid electrolyte of a solid storage battery can be provided. It is also possible to provide a material that can be used over a wide temperature range. In addition, a chemically modified graphene compound can be provided. Furthermore, a novel graphene compound can be provided.

[0030] According to one embodiment of the present invention, a storage battery having a shape-changing function, i.e., It is possible to provide a flexible storage battery. It is also possible to provide a novel battery that is flexible.

[0031] The description of these effects does not preclude the existence of other effects. The embodiment does not necessarily have to have all of these effects. , the specification, drawings, claims, etc., and It is possible to extract other effects from the claims and other descriptions. [Brief explanation of the drawings]

[0032] [Figure 1] FIG. 1 is a diagram illustrating a lithium-ion storage battery. [Figure 2] 1A and 1B are diagrams illustrating a flexible lithium-ion storage battery. [Figure 3] 1A and 1B are diagrams illustrating a flexible lithium-ion storage battery. [Figure 4] FIG. 1 is a diagram illustrating the results of FT-IR measurement. DETAILED DESCRIPTION OF THE INVENTION

[0033] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the following description, and various modifications in form and details are possible by those skilled in the art. Furthermore, the present invention should not be construed as being limited to the description of the following embodiments. It is not something that can be done.

[0034] In each drawing described in this specification, the positive electrode, negative electrode, active material layer, separator, outer casing, etc. The size and thickness of each component may be exaggerated for clarity of description. Therefore, each component is not necessarily limited by its size, and the correlation between each component is not necessarily limited by its size. It is not limited to a relative size.

[0035] In addition, in this specification, ordinal numbers such as first, second, third, etc. are used for convenience. It does not indicate the order of processes or the vertical positional relationship. The "first" can be replaced with "second" or "third" as appropriate. In addition, ordinal numbers used to specify one aspect of the present invention are used in the present specification and the like. The ordinal numbers used may not match.

[0036] In addition, in the configuration of the present invention described in this specification, etc., the same parts or parts having similar functions The same reference numerals are used for the components in different drawings, and the repeated explanations will be omitted. When referring to parts with similar functions, the hatch pattern is the same and no special reference numeral is attached. There may not be.

[0037] In this specification, flexibility refers to the property that an object is flexible and can be bent. It refers to the property of an object being able to deform in response to an external force applied to it, and is different from elasticity and pre-deformation. The question is whether an object can restore its original shape. A flexible object is one that can deform in response to an external force. A flexible object can also be used by fixing it in a deformed state. It may be used after being repeatedly deformed, or it may be used in an undeformed state.

[0038] In this specification, modification refers to chemically changing a graphene compound to form graphene. It can also refer to changing the function or properties of a compound. It can also refer to the addition of a functional group having a certain quality.

[0039] Furthermore, the contents described in the embodiments of the present invention can be used in appropriate combinations. Cut.

[0040] (Embodiment 1) In this embodiment, a graphene compound produced according to one embodiment of the present invention will be described. In addition, a method for producing a graphene compound by chemical modification will also be described. The graphene compound produced according to one embodiment of the present invention may be a compound containing lithium, sodium, magnesium, It has the function of conducting metal ions such as calcium, and is used, for example, as a solid-state material in lithium-ion batteries. However, one aspect of the present invention is not limited to this.

[0041] <Graphene compounds> First, graphene and graphene compounds will be described.

[0042] Graphene is a one-atom-thick sheet of carbon atoms arranged in a hexagonal lattice structure on a plane. The bonds between carbon atoms are stronger than those of diamond, making it extremely resistant to deformation and tension. On the other hand, it has extremely high conductivity and is highly resistant to lithium ions. Since the ions do not permeate the material sufficiently, it cannot be used as a solid electrolyte in lithium-ion batteries. It is not suitable for

[0043] However, in general, graphene can have various types of defects, such as lattice defects. In addition to the six-membered ring, the lattice may contain five-membered or seven-membered rings. There may be defects in which carbon is bonded to atoms other than carbon. By using a sintered material, atoms or atomic groups can be bonded to graphene to produce desired properties. Here, a graphene compound according to one embodiment of the present invention will be described.

[0044] Graphene is a single atomic layer of carbon atoms with π bonds between the carbon atoms. When two to 100 layers of graphene are stacked, they are sometimes called multi-graphene. Graphene and multi-graphene are, for example, The length is 50 nm or more and 100 μm or less, or 800 nm or more and 50 μm or less.

[0045] In this specification and the like, a compound having graphene or multigraphene as a basic skeleton "Graphene Compound" Graphene compounds include graphene and multigraphene. .

[0046] The graphene compound will be described in detail below.

[0047] Graphene compounds, for example, are compounds in which graphene or multigraphene has atoms other than carbon, or or a compound modified with an atomic group having an atom other than carbon. The atomic group that modifies multi-graphene may be called a substituent, a functional group, a characteristic group, or the like. In this specification, modification refers to a modification that is caused by a substitution reaction, an addition reaction, or other reaction. graphene, multi-graphene, graphene compounds, or graphene oxide (see below) This refers to the introduction of an atomic group containing atoms other than carbon or an atomic group mainly composed of carbon into .

[0048] The front and back surfaces of graphene may be modified with different atoms or atomic groups. In multi-graphene, each layer is modified with a different atom or atomic group. It may also be used.

[0049] An example of graphene modified with the above atoms or atomic groups is oxygen or oxygen-containing Examples of such graphene include graphene or multi-graphene modified with functional groups such as oxygen or oxygen Graphene compounds modified with functional groups having the formula In this specification, graphene oxide also includes multilayer graphene oxide. do.

[0050] Modifications are not limited to the introduction of a single atom or group, but can be achieved through multiple chemical reactions. The modification also refers to the introduction of multiple types of atoms or atomic groups. This also includes reactions that add atoms, hydrocarbon groups, aromatic hydrocarbon groups, and heterocyclic compound groups. Examples of reactions for introducing atomic groups into graphene include addition reactions and substitution reactions. , Friedel-Crafts reaction, Bingel reaction l) reaction, etc. may be carried out. A radical addition reaction may be carried out on graphene, A ring may be formed between the graphene and the atomic group by an addition reaction.

[0051] Next, an example of a method for producing graphene oxide will be described. Alternatively, multi-graphene can be obtained by oxidizing the graphene. Graphite oxide can be obtained by oxidizing graphite. Here, graphene oxide can be further modified with the above-mentioned atoms or atomic groups. You may do so.

[0052] The compound obtained by reducing graphene oxide is called "RGO (Reduced Graphene Oxide)." RGO is sometimes called "graphene oxide." Not all of the oxygen is eliminated, and some oxygen or atomic groups containing oxygen remain bonded to carbon. There may be cases where this information exists.

[0053] Graphene compounds are composed of multiple graphene compounds that overlap partially to form a single sheet. Such a graphene compound may be referred to as a graphene compound sheet. The graphene compound sheet has a thickness of, for example, 0.33 nm or more and 10 mm or less, Preferably, the graphene compound sheet has a region of greater than 0.34 nm and less than 10 μm. The group is an atom other than carbon, an atomic group containing atoms other than carbon, or a group containing mainly carbon such as an alkyl group. The graphene compound sheet may be modified with an atomic group such as Each of the several layers may be modified with a different atom or atomic group.

[0054] Graphene compounds are composed of not only six-membered rings made up of carbon but also five-membered rings made up of carbon and In this case, in the vicinity of the seven-membered ring or more, In this case, there may be an area through which lithium ions can pass.

[0055] Furthermore, for example, a plurality of graphene compounds may be gathered together to form a sheet shape.

[0056] The graphene compound has a planar shape, which allows for surface contact.

[0057] <Chemically modified graphene compounds> Next, a chemically modified graphene compound will be described. The graphene compound produced by this method is used, for example, as a solid electrolyte in a lithium ion battery. In this case, the positive and negative electrodes should be electrically insulated to prevent short-circuiting. The graphene compound according to one embodiment of the present invention must contain only lithium. It also has conductivity of metal ions such as sodium, magnesium, and calcium. It can also be used for purposes other than lithium ion storage batteries. We will explain about storage batteries that use lithium ions as carriers, as a representative of such metal ions. However, the explanation can also be applied to batteries using other metal ions as carriers. Cut.

[0058] Pure graphene is known to be highly conductive, and as is, it is not suitable for lithium-ion storage. Graphene oxide cannot be used as a solid electrolyte in batteries, and its conductivity is relatively low. However, it has poor resistance to reduction and is easily reduced to highly conductive RGO. To make it insulating, graphene oxide or graphene is chemically modified to make it insulating. For example, it is preferable to use a molecule having an alkyl chain with a relatively large number of carbon atoms to form graphene oxide. It is conceivable to chemically modify graphene or graphene. When modified with a compound having a long alkyl chain, the alkyl chain becomes a functional group with poor electrical conductivity. Therefore, the distance between multiple graphene oxide sheets is increased, inhibiting electron conduction. Therefore, it can be insulated.

[0059] However, alkyl groups are non-polar functional groups and are responsible for the battery reaction in lithium-ion batteries. It has low affinity with lithium ions. Therefore, it is difficult to use compounds with long-chain alkyl groups. When phene is chemically modified, the movement of lithium ions is inhibited, inhibiting the battery reaction. In addition, the lithium salt is difficult to dissociate. Therefore, compounds having long-chain alkyl groups are Lithium-ion batteries using graphene compounds modified with ZnO as solid electrolytes have shown excellent properties. becomes lower.

[0060] Therefore, the graphene compound according to one aspect of the present invention has insulating properties and at the same time has lithium ion. For example, a graphene compound with an affinity for cations is prepared by chemical modification. It is preferable that the graphene compound has a chain-like functional group having an ether bond. It has polarity and is classified as a hydrophilic group, and its polarity gives it affinity with lithium ions. Furthermore, the graphene compound can contribute to the movement of lithium ions. When used as a solid electrolyte for ion storage batteries, the ether functional group of the graphene compound is A larger number of bond chains is preferable because it improves the mobility of lithium ions.

[0061] Furthermore, the graphene compound according to one embodiment of the present invention has properties as a solid electrolyte that are similar to those of a polymer. Compared to electrolytes, one of their features is their high heat resistance. If damage to the internal structure causes an unexpected reaction, it could develop into a major accident such as a fire or explosion. High heat resistance is important because there is a possibility that the lithium-ion battery may be damaged. When used in harsh environments such as The graphene compound according to one embodiment of the present invention has high heat resistance and can withstand such an environment. Therefore, it is suitable for use as a solid electrolyte in lithium-ion batteries. .

[0062] Here, a general example of a chemically modified graphene compound according to one embodiment of the present invention will be shown. The formula is shown below.

[0063] [ka]

[0064] In the formula (200), R is a substituted or unsubstituted group having at least two ether bonds. R represents an unsubstituted chain group, and R may be branched. GO is a compound of graphene or an acid. The graphene of the graphene compound according to one embodiment of the present invention is represented by the molecular It is not limited to a single amount or structure, and graphene of any size can be used. Therefore, the molecular structure of the graphene compound according to one embodiment of the present invention is specified in detail, and It is impossible to fully describe the chemically modified graphene according to one embodiment of the present invention. The phenanthrene compound is a compound having a substituted or unsubstituted group with at least two or more ether bonds. The graphene compound is chemically modified with a silylating agent. There are cases where it is practical to identify In addition, GO and Si are bonded together by two Si-O bonds as shown in the above formula. In some cases, the molecules are immobilized in an O layer, but in other cases, the molecules are immobilized by one or three Si-O bonds. In addition, the bond is not limited to the Si-O bond, and other bonds may also be used. The antibody may be immobilized by

[0065] <Chemical modification> Next, the graphene compound is chemically modified to produce a chemically modified graphene compound. The method will be explained using the following synthesis scheme (A-1).

[0066] [ka]

[0067] As shown in the synthesis scheme (A-1), graphene oxide (GO) and two or more ethers are synthesized. The target compound can be obtained by chemically modifying a silylating agent containing a chain-like group with a bond. In the synthetic scheme (A-1), R is at least two substituted or unsubstituted groups. The above represents a chain group having an ether bond, and R may be branched.

[0068] In the synthesis scheme (A-1), the base that can be used is butylamine, phenanthroline ... butylamine, hexylamine, diethylamine, dipropylamine, dibutylamine, Examples include organic bases such as triethylamine, tripropylamine, and pyridine. However, the bases that can be used are not limited to these.

[0069] In the synthesis scheme (A-1), solvents that can be used include toluene, xylene, Aromatic hydrocarbons such as ethylene glycol, mesitylene, etc., hydrocarbons such as hexane and heptane, and ethylene glycol Examples of ethers that can be used include ethanol dimethyl ether. The solvents that can be used are not limited to these. In particular, when a primary amine is used as the base and an aromatic solvent is used as the solvent, A combination using a hydrocarbon is more preferred.

[0070] Silylating agents other than those shown in the synthetic scheme (A-1) that have a trialkoxysilyl group However, the present invention is not limited to these.

[0071] <Example> Examples of silylating agents containing a chain group having two or more ether bonds are given below. By using these silylating agents, chemical modification can be achieved by the chain group having an ether bond. Decorated graphene compounds can be prepared.

[0072] [ka]

[0073] [ka]

[0074] [ka]

[0075] [ka]

[0076] [ka]

[0077] [ka]

[0078] In the formulas (137) to (148), OMe represents a methoxy group, and OEt represents an ethoxy group. By using the above-mentioned silylating agent, at least two or more ether bonds can be obtained. It is possible to produce a graphene compound having a chain-like group having these silyl groups. Graphene compounds chemically modified with a chemical agent have low electronic conductivity, while lithium ions are easily absorbed. Because of its high ionic conductivity, it is used as a material for solid electrolytes and separators in lithium-ion batteries. However, the graphene compound according to one aspect of the present invention is suitable as a material for It is not limited to being prepared using a silylating agent.

[0079] Note that one embodiment of the present invention has been described in this embodiment. However, the present invention is not limited to these. For example, in one embodiment of the present invention, a chain having at least two or more ether bonds Although an example of a graphene compound having a group having a .alpha.-type structure has been shown, one embodiment of the present invention is not limited thereto. In some cases, or depending on the situation, one aspect of the present invention is to The graphene compound does not have to have a chain group having an ether bond. In some cases, or depending on the situation, one aspect of the present invention is to It is not necessary for the polymer to have a chain structure having chain bonds.

[0080] Note that this embodiment mode can be combined with other embodiment modes as appropriate.

[0081] (Embodiment 2) In this embodiment, a lithium ion battery using a graphene compound according to one embodiment of the present invention will be described. The structure of the pond will be explained.

[0082] A method for manufacturing the lithium-ion battery 110 according to one embodiment of the present invention is shown in FIGS. The following description will be made with reference to FIG. 1(B). FIG. 1(B) is a cross-sectional view of the lithium ion battery 110. A positive electrode current collector 100, a positive electrode active material layer 101, a solid electrolyte layer 104, and a negative electrode active material 1 is a cross section of the laminated layer 103 and the negative electrode current collector 102, which are then sealed with an exterior body 207. It is to be noted that the active material layer can be formed on both sides of the current collector, and the storage battery can be formed in a stacked structure. It is also possible to do so.

[0083] <Positive electrode configuration> The positive electrode includes a positive electrode active material layer 101 and a positive electrode current collector 100.

[0084] The positive electrode active material used in the positive electrode active material layer 101 is a carrier such as lithium ions. Materials that allow ion insertion and desorption can be used, such as olivine-type crystal structures. Examples of such a material include a lithium-containing material having a layered rock salt type crystal structure or a spinel type crystal structure. In addition, for example, a polyanion-based positive electrode material can be used as the positive electrode active material. Examples of polyanion-based positive electrode materials include materials with an olivine-type crystal structure, pear-type Con-type materials, etc.

[0085] Various composite oxides can be used as the positive electrode active material. Compounds such as iCoO2, LiNiO2, LiMn2O4, V2O5, Cr2O5, and MnO2 Things can be used.

[0086] As a material with a layered rock salt type crystal structure, for example, a composite oxide represented by LiMO2 is used. The element M is preferably at least one selected from Co and Ni. LiCoO2 has a large capacity, is stable in air, and is thermally stable. The element M is preferably one or more selected from Co and Ni. In addition to the above, it may contain one or more selected from Al and Mn. For example, LiCo x Mn y Ni z O w (x, y, z and w are, for example, x=y=z=1 / 3 or their vicinity.) , w=2 or nearby) can be used.

[0087] The neighborhood is, for example, a value that is greater than 0.9 times and less than 1.1 times the value.

[0088] In addition, as the positive electrode active material, for example, a solid solution of a combination of multiple composite oxides is used as the positive electrode active material. For example, LiCo 1 / 3 Mn 1 / 3 Ni 1 / 3 O2 and Li2Mn A solid solution of O3 can be used as a positive electrode active material.

[0089] As an example of a material with a spinel-type crystal structure, a composite oxide represented by LiM2O4 is It is preferable to have Mn as the element M. For example, LiMnO Furthermore, by including Ni in addition to Mn as the element M, the storage This is preferable because it can improve the discharge voltage of the battery and increase the energy density. A small amount of lithium-containing material with a spinel-type crystal structure containing manganese, such as Mn2O4, Lithium nickel oxide (LiNiO2 and LiNi (1-x)M x O2(M=Co, Al etc. )) is preferably mixed, as this can improve the characteristics of the storage battery.

[0090] For example, the average particle size of the primary particles of the positive electrode active material is 5 nm or more and 100 μm or less. Preferably, the thickness is 50 nm or more and 50 μm or less, more preferably, 100 nm or more and 500 μm or less. It is more preferable that the specific surface area is 5m 2 / g or more 15m 2 / g or less It is preferable that the average particle size of the secondary particles is 5 μm or more and 50 μm or less. The average particle size is preferably measured by observation using a SEM (scanning electron microscope) or a TEM. Alternatively, it can be measured by a particle size distribution analyzer using a laser diffraction / scattering method. The specific surface area can be measured by a gas adsorption method.

[0091] A conductive material such as a carbon layer may be provided on the surface of the positive electrode active material. For example, a carbon layer on the positive electrode active material can improve the conductivity of the electrode. The coating is formed by mixing carbohydrates such as glucose when baking the positive electrode active material. can be done.

[0092] For example, a polyanion-based positive electrode material containing oxygen, element X, metal A, and metal M may be used. The metal M can be Fe, Mn, Co, or Ni. , Ti, V, Nb, or more; metal A is one or more of Li, Na, Mg, or more; and element X is It is one or more of S, P, Mo, W, As, and Si.

[0093] In addition, the composite material (general formula LiMPO4 (M is Fe(II), Mn(II), Co(II) ) and Ni(II)) can be used. Representative examples of the general formula LiMPO4 include LiFePO4, LiNiPO4, LiCoPO4, LiMnPO4, LiFe a Ni b PO4, LiFe a Co b PO4, LiFe a Mn b PO4, LiNi a Co b P O4, LiNi a Mn b PO4(a+b is less than 1, 0 <a<1、0<b<1)、LiFe c Ni d Co e PO4, LiFe c Ni d Mn e PO4, LiNi c Co d Mn e PO4 (c+d+e is less than 1, 0 <c<1、0<d<1、0<e<1)、LiFe f Ni g Co h Mn i PO4(f+g+h+i is 1 or less, 0 <f<1、0<g<1、0<h<1、0< Lithium compounds such as i<1) can be used.

[0094] In particular, LiFePO4 is safe, stable, has high capacity density, and can be extracted during initial oxidation (charging). It satisfies the requirements for a positive electrode active material in a balanced manner, such as the presence of lithium ions. ,preferable.

[0095] Also, the general formula Li (2-j) MSiO4 (M is Fe(II), Mn(II), Co(I) A composite material such as one or more of Ni(I), Ni(II), 0≦j≦2) can be used. Li (2-j)As representative examples of MSiO4, Li (2-j) FeSiO4, Li (2- j) NiSiO4, Li (2-j) CoSiO4, Li (2-j) MnSiO4, Li ( 2-j) Fe k Ni l SiO4, Li (2-j) Fe k Co l SiO4, Li (2-j) Fe k Mn l SiO4, Li (2-j) Ni k Co l SiO4, Li (2-j) Ni k M n l SiO4 (k + l is 1 or less, 0 < k < 1, 0 < l < 1), Li (2-j) Fe m Ni n Co q SiO4, Li (2-j) Fe m Ni n Mn q SiO4, Li (2-j) Ni m Co n Mn q SiO4 (m + n + q is 1 or less, 0 < m < 1, 0 < n < 1, 0 < q < 1), Li (2-j) Fe r Ni s Co t Mn u SiO4 (r + s + t + u is 1 or less, 0 < r < 1, 0 < s < 1, 0 < t < 1, 0 < u < 1), etc., can be used as materials of lithium compounds.

[0096] Also, A x M2(XO4)3 (A = Li, Na, Mg, M = Fe, Mn, Ti, V, Nb The Nasicon type compound represented by the general formula (X = S, P, Mo, W, As, Si) is used. Nasicon-type compounds include Fe2(MnO4)3, Fe2(SO4)3, Li3Fe2(PO4)3, etc. Also, as a positive electrode active material, Li2MPO4F, Li Use compounds represented by the general formula 2MP2O7, Li5MO4 (M = Fe, Mn) can be done.

[0097] In addition, polyanionic positive electrode materials containing V can be used. Representative examples include α-L iVOPO4, β-LiVOPO4, α1-LiVOPO4, LiVPO4F, LiVP O4O, LiVP2O7, LiVOSO4, Li2VOSiO4, LiVMoO6, etc. Examples include:

[0098] In addition, as the positive electrode active material, perovskite-type fluorides such as NaFeF3 and FeF3, Ti Metal chalcogenides (sulfides, selenides, tellurides) such as S2 and MoS2, LiMV Oxides with an inverse spinel crystal structure such as O4, vanadium oxides (V2O5, V6 O 13 Materials such as manganese oxides and organic sulfur compounds can be used. Cut.

[0099] In addition, the positive electrode active material is a lithium ion battery with the general formula LiMBO3 (where M is Fe(II), Mn(II), C o(II)) can be used.

[0100] In addition, the positive electrode active material is a compound having the composition formula Li a Mn b M c O d Lithium-manganese can be expressed as A manganese composite oxide can be used. Here, element M is selected from elements other than lithium and manganese. The selected metal element, silicon, or phosphorus is preferably used, and nickel is preferred. Further, when measuring the entire particle of the lithium manganese composite oxide, When the value is 0 <a / (b+c)<2、かつc>0 and 0.26≦(b+c) / d<0.5, In order to realize high capacity, it is preferable to have a crystal structure between the surface layer and the center. To obtain a lithium manganese composite oxide having regions with different crystal orientations or oxygen contents In order to obtain such a lithium manganese composite oxide, it is preferable that, for example, 1.6≦a It is preferable that c / b≦1.848, 0.19≦c / b≦0.935, and 2.5≦d≦3. Furthermore, Li 1.68 Mn 0.8062 Ni 0.318 Lithium with the formula O3 It is particularly preferable to use lithium manganese composite oxide. 1.6 8Mn 0.8062 Ni 0.318 Lithium manganese complex oxide represented by the formula O3 The ratio (molar ratio) of the amounts of raw materials is Li2CO3:MnCO3:NiO=0. Lithium manganese composite oxide formed by mixing 84:0.8062:0.318 Therefore, the lithium manganese composite oxide has the composition formula Li 1.68 Mn 0.806 2Ni 0.318 It is expressed as O3, but the composition may deviate from this.

[0101] The composition of metals, silicon, phosphorus, etc. of the entire lithium manganese composite oxide particle is, for example, For example, it can be measured using an ICP-MS (inductively coupled plasma mass spectrometer). The oxygen composition of the entire particle of the lithium manganese composite oxide can be measured by, for example, EDX (energy dispersive X-ray diffraction). ​It can be measured using X-ray analysis. It can also be used in combination with ICP-MS analysis. Determined by using valence evaluation of fused gas analysis and XAFS (X-ray absorption fine structure) analysis The lithium manganese composite oxide is a compound containing at least lithium and manganese. It refers to oxides containing chromium, cobalt, aluminum, nickel, iron, magnesium, molybdenum, and such as iridium, zinc, indium, gallium, copper, titanium, niobium, silicon, and phosphorus It may contain at least one element selected from the group consisting of:

[0102] In addition, the carrier ions are alkali metal ions other than lithium ions, alkaline earth metal ions, etc. In the case of metal ions, alkali metals (e.g., sodium) are used as the positive electrode active material instead of lithium. alkaline earth metals (e.g., calcium, strontium, barium, etc.), For example, a layered oxide containing sodium may be used. can be used.

[0103] Examples of materials containing sodium include NaFeO2 and Na 2 / 3 [Fe 1 / 2 Mn1 / 2 ]O2, Na 2 / 3 [Ni 1 / 3 Mn 2 / 3 ]O2, Na2Fe2(SO4)3, N a3V2(PO4)3, Na2FePO4F, NaVPO4F, NaMPO4 (M is F e(II), Mn(II), Co(II), Ni(II)), Na2FePO4F, Na Sodium-containing oxides such as 4Co3(PO4)2P2O7 are used as the positive electrode active material. It is possible.

[0104] In addition, lithium-containing metal sulfides can be used as the positive electrode active material. 2TiS3, Li3NbS4, etc.

[0105] The positive electrode active material preferably has an average primary particle size of 50 nm to 100 μm. .

[0106] The positive electrode active material, together with the negative electrode active material, plays a central role in the battery reaction of the storage battery and It is a substance that releases and absorbs. To extend the life of a storage battery, it is necessary to reduce the irreversible reaction of the battery. It is preferable that the material has a small capacity related to the charge and discharge, and it is preferable that the material has a high charge and discharge efficiency. It's nice.

[0107] As the active material comes into contact with the electrolyte, it reacts with the electrolyte, causing the active material to be lost and deteriorated. When the battery is degraded, the capacity of the battery decreases. It is desirable that such reactions do not occur within the pond.

[0108] As a conductive additive for the electrodes, acetylene black (AB), graphite particles, carbon Carbon nanotubes, graphene, fullerenes, etc. can be used.

[0109] The conductive additive can form an electrically conductive network in the electrode. This allows the electrical conduction path between the positive electrode active materials to be maintained. By adding an electrical auxiliary agent, it is possible to realize a positive electrode active material layer 101 having high electrical conductivity. This can be done.

[0110] In addition to the typical polyvinylidene fluoride (PVDF), polyimide is also used as a binder. , polytetrafluoroethylene, polyvinyl chloride, ethylene propylene diene poly rubber, fluoro rubber, polymethyl methacrylate, polyethylene, nitrocellulose, etc. You can be there.

[0111] The content of the binder relative to the total amount of the positive electrode active material layer 101 is 0.5 wt% or more and 10 wt% or less. Preferably, 2 wt% or more and 8 wt% or less is more preferable, and 3 wt% or more and 5 wt% or less is more preferable. The content of the conductive additive with respect to the total amount of the positive electrode active material layer 101 is more preferably 1w The content is preferably t% or more and 10wt% or less, and more preferably 1wt% or more and 5wt% or less.

[0112] When the positive electrode active material layer 101 is formed by the coating method, the positive electrode active material, the binder, and the conductive additive are mixed. The agent and the dispersion medium are mixed to prepare an electrode slurry, which is then applied to the positive electrode current collector 100 and dried. That's fine.

[0113] The positive electrode current collector 100 may be made of metals such as stainless steel, gold, platinum, aluminum, titanium, etc. and their alloys, which are highly conductive and do not alloy with carrier ions such as lithium. In addition, silicon, titanium, neodymium, scandium, molybdenum, etc. Aluminum alloys containing elements that improve heat resistance can be used. Alternatively, the metal element may be formed of a metal element that reacts with silicon to form a silicide. Metal elements that form silicides include zirconium, titanium, hafnium, and vanadium. Sodium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel, etc. The positive electrode current collector is available in foil, plate (sheet), mesh, punched metal, expanded A metal shape or the like can be used as appropriate.

[0114] Through the above steps, a positive electrode for a lithium ion battery can be produced.

[0115] <Negative electrode configuration> Next, the negative electrode will be described. The negative electrode includes a negative electrode active material layer 103 and a negative electrode current collector 102. The process for forming the negative electrode is described below.

[0116] As the negative electrode active material used in the negative electrode active material layer 103, the carbon-based material may be graphite, graphite-based carbon, or the like. graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon nanotubes Examples of graphite include mesocarbon microbeads, graphene, and carbon black. Artificial graphite such as MCMB, coke-based artificial graphite, pitch-based artificial graphite, and spherical natural graphite There is natural graphite such as lead. Graphite also comes in flake and spherical shapes. .

[0117] In addition to carbon-based materials, negative electrode active materials include those that charge and discharge by alloying and dealloying reactions with lithium. Materials capable of undergoing a reaction can also be used, such as Ga, Si, Al, Ge, A material containing at least one of Sn, Pb, Sb, Bi, Ag, Zn, Cd, In, etc. These elements have a larger capacity than carbon, and silicon in particular has a theoretical The capacity is as high as 4200mAh / g, which is preferable. , for example, Mg2Si, Mg2Ge, Mg2Sn, SnS2, V2Sn3, FeSn2, CoSn2, Ni3Sn2, Cu6Sn5, Ag3Sn, Ag3Sb, Ni2MnSb, CeSb3, LaSn3, La3Co2Sn7, CoSb3, InSb, SbSn, etc. do.

[0118] In addition, the negative electrode active material is SiO, SnO, SnO2, titanium dioxide (TiO2), lithium Sodium titanium oxide (Li4Ti5O 12 ), lithium-graphite intercalation compound (Li x C6), Niobium pentoxide (Nb2O5), tungsten oxide (WO2), molybdenum oxide (MoO2 ) and other oxides can be used.

[0119] In addition, the negative electrode active material is a composite nitride of lithium and transition metals, which has a Li3N structure. Li (3-x) M x N (M is Co, Ni or Cu) can be used. For example, L i 2.6 Co 0.4 N3 has a large charge / discharge capacity (900mAh / g, 1890mAh / cm 3 ) and is preferred.

[0120] When a composite nitride of lithium and transition metals is used, lithium is included in the negative electrode active material, so the positive electrode active material It can be combined with materials such as V2O5 and Cr3O8 that do not contain lithium. Even when using a material containing lithium as the positive electrode active material, it is necessary to preliminarily By removing the lithium contained in the battery, a composite nitride of lithium and transition metals is produced as the negative electrode active material. can be used.

[0121] In addition, a material that undergoes a conversion reaction can also be used as the negative electrode active material. , cobalt oxide (CoO), nickel oxide (NiO), iron oxide (FeO), etc. A transition metal oxide that does not undergo an alloying reaction with the negative electrode active material may be used. Further materials that undergo a reaction include Fe2O3, CuO, Cu2O, RuO2, and Cr2O Third order oxide, CoS 0.89, NiS, CuS and other sulfides, Zn3N2, Cu3N, G Nitrides such as e3N4, phosphides such as NiP2, FeP2, CoP3, FeF3, BiF3 This also occurs with fluorides such as

[0122] For example, the particle size of the negative electrode active material is preferably 50 nm or more and 100 μm or less. .

[0123] In both the positive electrode active material layer 101 and the negative electrode active material layer 103, a plurality of active materials are used. The materials may be used in combination at a specific ratio. This allows the performance of the active material layer to be selected in more detail.

[0124] As a conductive additive for the electrodes, acetylene black (AB), graphite particles, carbon Carbon nanotubes, graphene, fullerenes, etc. can be used.

[0125] The conductive additive can form an electrically conductive network in the electrode. This allows the electrical conduction path between the negative electrode active materials to be maintained. By adding an electrical auxiliary agent, it is possible to realize a negative electrode active material layer 103 having high electrical conductivity. This can be done.

[0126] In addition to the typical polyvinylidene fluoride (PVDF), polyimide is also used as a binder. , polyvinyl chloride, ethylene propylene diene polymer, styrene-butadiene glycol Rubber, acrylonitrile-butadiene rubber, fluororubber, polyvinyl acetate, polymethylmethacrylate Acrylate, polyethylene, nitrocellulose, etc. can be used.

[0127] The content of the binder relative to the total amount of the negative electrode active material layer 103 is 1 wt % or more and 10 wt % or less. is preferable, 2 wt% or more and 8 wt% or less is more preferable, and 3 wt% or more and 5 wt% or less is even more preferable. It is more preferable that the content of the conductive additive with respect to the total amount of the negative electrode active material layer 103 is 1 wt %. The content is preferably from 1 wt % to 10 wt %, and more preferably from 1 wt % to 5 wt %.

[0128] Next, a negative electrode active material layer 103 is formed on the negative electrode current collector 102. When forming the porous layer 103, a negative electrode active material, a binder, a conductive additive, and a dispersion medium are mixed and then spun. A slurry is prepared, applied to the negative electrode current collector 102, and dried. Pressing may also be performed.

[0129] The negative electrode current collector 102 may be made of stainless steel, gold, platinum, iron, copper, titanium, tantalum, or the like. Metals and their alloys have high conductivity and do not alloy with carrier ions such as lithium. Materials can be used. Metal elements that react with silicon to form silicides can also be used. The metal element that reacts with silicon to form silicide is zirconium. Cr, titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten The negative electrode current collector 102 may be in the form of a foil, a plate (sheet), or the like. , mesh, cylindrical, coil, punched metal, expanded metal, etc. The negative electrode current collector 102 has a thickness of 5 μm or more and 30 μm or less. In addition, it is preferable to undercoat part of the surface of the electrode current collector with graphite or the like. A layer may be provided.

[0130] Through the above steps, a negative electrode for a lithium ion battery can be produced.

[0131] ≪Solid electrolyte layer≫ <Mixing of Li salt> When a graphene compound according to one embodiment of the present invention is used in a solid electrolyte, the graphene compound is mixed with a Li salt.

[0132] For example, a solution in which a graphene compound according to one embodiment of the present invention is dispersed in tetrahydrofuran (THF) and a solution in which LiTFSA (lithium bis(trifluoromethanesulfonyl)amide) is dispersed in THF are mixed. Next, one or more drops of this are dropped onto a material for forming a solid electrolyte layer, simply dried on a hot plate, and then dried under reduced pressure at a temperature of 90 °C to form a solid electrolyte layer. The solid electrolyte layer may be in the form of a film . The solid electrolyte layer 104 is sandwiched between a positive electrode and a negative electrode and housed in an exterior body.

[0133] Note that the method for mixing a Li salt for using a graphene compound according to one embodiment of the present invention in a solid electrolyte is not limited to this.

[0134] Also, a separator may be sandwiched between the positive electrode and the negative electrode together with the solid electrolyte layer 104. The separator must have insulating performance to prevent contact between both electrodes, performance to hold an electrolyte solution, and ion conductivity.

[0135] Also, a sheet-like or envelope-like separator having a size that can cover both sides of one of the positive electrode or the negative electrode is formed, and when used as an electrode wrapped by the separator, it is possible to protect the electrode from mechanical damage during the manufacture of the storage battery, and the handling of the electrode becomes easy. By housing the electrode wrapped by the separator and the other electrode together in an exterior body, a storage battery can be formed. ​

[0136] Furthermore, the separator is made of fluorine-based polymer, polyethylene oxide, polypropylene oxide, etc. Polyethers such as oxide, polyolefins such as polyethylene and polypropylene, polyacrylic Lylonitrile, polyvinylidene chloride, polymethyl methacrylate, polymethyl acrylate Polyvinyl alcohol, polymethacrylonitrile, polyvinyl acetate, polyvinyl Aminopropyl pyrrolidone, polyethyleneimine, polybutadiene, polystyrene, polyisoprene, Polyurethane polymers and their derivatives, cellulose, paper, nonwoven fabric, glass fiber The solid electrolyte layer 10 may be formed of any one of the above materials or a combination of two or more of them. By using the separator in combination with the membrane 4, the battery This allows for a wide range of separator performance options.

[0137] Furthermore, the storage battery may be flexible, and a deformation stress is applied to the flexible storage battery. In this case, the solid electrolyte layer 104 and the separator slide against each other at the interface between them. Therefore, the structure having both the solid electrolyte layer 104 and the separator can be used. The structure is also suitable as a separator structure for a flexible storage battery.

[0138] Through the above steps, the solid electrolyte layer 104 can be incorporated into the lithium ion battery.

[0139] <Exterior body configuration> Next, the exterior body 207 will be described. The exterior body 207 is made of, for example, polyethylene, polypropylene, or the like. Al is applied to a membrane made of a material such as propylene, polycarbonate, ionomer, or polyamide. A thin metal film with excellent flexibility, such as aluminum, stainless steel, copper, or nickel, is applied, and the metal On the thin film, an insulating synthetic resin such as polyamide resin or polyester resin is applied as the outer surface of the exterior body. A three-layer film having a membrane can be used. It blocks the permeation of electrolyte and gas, ensures insulation, and is also electrolyte-resistant. Fold the exterior body inward and stack them, or place the two exterior bodies with their inner surfaces facing each other. By stacking them and applying heat, the inner material melts and the two outer bodies are fused together, forming a seal. A stop structure can be created.

[0140] If the sealing portion is the part where the exterior body is fused or otherwise formed into a sealed structure, the exterior body can be folded inward. When the package is folded and stacked, a sealing portion is formed at a location other than the fold, and the first region of the exterior body and The first area and the overlapping second area are fused together. When the adhesive is melted, a sealing portion is formed around the entire periphery by a method such as heat sealing.

[0141] <Flexible storage battery> When a flexible material is selected from the materials of each member shown in this embodiment, It is possible to fabricate a flexible lithium-ion battery. There has been active research and development into flexible batteries for use in such devices. This has created a demand for storage batteries.

[0142] The battery is made of two films sandwiching the battery materials 1805, such as electrodes and solid electrolytes, between them. When the battery is bent, the radius of curvature of the film 1801 closest to the center of curvature 1800 of the battery is 1 802 is smaller than the radius of curvature 1804 of the film 1803 on the side farther from the center of curvature 1800. If the battery is bent to make the cross section arc-shaped, the center of curvature is close to 180° (Fig. 2(A)). The surface of the film is subjected to compressive stress, and the surface of the film far from the center of curvature 180° is subjected to tension. Tensile stress is applied (Figure 2(B)).

[0143] When a flexible lithium-ion battery is deformed, a large stress is applied to the exterior. When a pattern consisting of recesses or protrusions is formed on the surface of the exterior body, the pressure generated by the deformation of the storage battery is reduced. Even if compressive stress or tensile stress is applied, the effects of strain can be suppressed. Therefore, the radius of curvature of the exterior body of the battery on the side closest to the center of curvature is 50 mm, preferably 30 mm. It can be deformed within the range.

[0144] The radius of curvature of a surface will be explained with reference to FIG. 3. In FIG. 3(A), a curved surface 1700 is cut. In a cross-sectional plane 1701, a part of a curve 1702 included in a curved surface 1700 is approximated to an arc of a circle. Similarly, the radius of the circle is the radius of curvature 1703, and the center of the circle is the center of curvature 1704. 3(B) shows a top view of the curved surface 1700. FIG. 3(C) shows the curved surface 1700 in a plane 1701. When cutting a curved surface with a plane, the angle of the plane relative to the curved surface and the cutting The radius of curvature of the curve that appears in the cross section varies depending on the position. The smallest radius of curvature is taken as the radius of curvature of the surface.

[0145] The cross-sectional shape of the storage battery is not limited to a simple arc shape, and may be a shape having a partial arc. For example, the shape shown in FIG. 2(C), a wavy shape (FIG. 2(D)), an S-shape, etc. If the curved surface of the storage battery has a shape with multiple centers of curvature, The two exterior bodies are connected at the surface with the smallest curvature radius among the curvature radii at each center. The radius of curvature of the outer casing closer to the center of curvature is 50 mm, preferably 30 mm. The battery can be deformed.

[0146] <Battery assembly and aging> Next, the above-mentioned components are combined to seal the exterior body 207, thereby forming the device shown in FIG. As shown in (B) and (C), a positive electrode current collector 100, a positive electrode active material layer 101, and a solid electrolyte layer 104 The negative electrode active material layer 103 and the negative electrode current collector 102 are stacked together, and the stack is sealed with an exterior body 207. It is assumed to be in this state.

[0147] Next, an aging step may be performed. First, the ambient temperature is kept at, for example, room temperature, and then a low laser beam is applied. Next, the battery is charged with a constant current until the voltage reaches the matching voltage. Next, the battery is charged at a rate higher than the initial charge.

[0148] Then, store it in a slightly higher temperature environment for a long period of time, for example, in an environment of 40°C or higher for 24 hours or more. Save above.

[0149] After long-term storage in a slightly high temperature environment, the gas generated in the area inside the exterior body is released again. Furthermore, discharge the battery at a rate of 0.2C in a room temperature environment, charge it at the same rate, and then charge it again at the same rate. After discharging at the same rate, the battery is charged again at the same rate. The aging process is completed.

[0150] In this manner, the storage battery according to the present invention can be manufactured.

[0151] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0152] In this specification, etc., in a drawing or text that describes one embodiment, If at least one specific example is described, it is not possible to derive a generic concept of that specific example. This will be easily understood by those skilled in the art. When at least one specific example is described in a figure or text, the general outline of that specific example is The invention is also disclosed as an aspect of the invention and may constitute an aspect of the invention. Therefore, one aspect of the invention can be said to be clear.

[0153] In this specification, at least the contents shown in the drawings (or even a part of the drawings) This is disclosed as one aspect of the invention and can constitute one aspect of the invention. Therefore, if something is shown in a diagram, it is not necessarily stated in words. However, the content is disclosed as one aspect of the invention and constitutes one aspect of the invention. Similarly, even if a part of the drawings is taken out, it can be regarded as one embodiment of the invention. This is disclosed as an embodiment of the present invention. It can be said that one aspect of the invention is clear. [Example]

[0154] Example 1 This example is a synthesis example of a graphene compound according to one embodiment of the present invention described in Embodiment 1. This article explains:

[0155] <Synthesis Example 1> First, let us consider a synthesis example of graphene oxide having a structure represented by the following formula (201): explain.

[0156] [ka]

[0157] First, graphene oxide (manufactured by Nishina Materials Co., Ltd., product name: R AP dGO (TQ-11)-1) 0.31 g, n-butylamine 4.2 g (58 mmol) l) was added. This mixture was irradiated with ultrasound for 5 minutes under a nitrogen stream, and then heated at 60°C for 1 hour. After stirring, the mixture was cooled to room temperature, 15 mL of toluene was added, and ultrasonic waves were applied for 5 minutes. The mixture was cooled to 0°C and then irradiated with methoxytriethyleneoxypropyltrichloroisothiazolinone. 8.0 g (24 mmol) of rosilane (CAS number: 228700-87-6) was added dropwise. The mixture was stirred at 60°C for 5 hours. After stirring, toluene was added to the mixture to wash it. The solid was collected by suction filtration, and the obtained solid was further washed with ethanol and acetone. The resulting solid was dried to obtain 0.39 g of the target black powder. The synthesis scheme (A) is shown below.

[0158] [ka]

[0159] <Synthesis Example 2> Next, another synthesis example of the graphene compound according to one embodiment of the present invention described in Embodiment 1 will be described. That is, graphene oxide having a structure represented by the following formula (202) A synthesis example will be described.

[0160] [ka]

[0161] In a 50 mL two-neck flask, 0.30 g of graphene oxide (manufactured by Nippon Material Co., Ltd., trade name: Rap dGO(TQ-11)-1) and 4.3 g (59 mmol) of n-butylamine were added. This mixture was irradiated with ultrasonic waves for 5 minutes under a nitrogen stream, and further stirred at 60 °C for 1 hour After stirring, the mixture was cooled to room temperature, 15 mL of toluene was added, and ultrasonic waves were irradiated for 5 minutes The mixture was cooled to 0 °C, and 14 g of 2-[methoxy(polyethyleneoxy)6-9 propyl yl]trichlorosilane (CAS No.: 36493-41-1) was added dropwise. This mix The mixture was stirred at 60 °C for 5 hours. After stirring, toluene was added to the mixture for washing, and the solid was recovered by suction filtration. The obtained solid was further washed with ethanol and acetone. When the obtained solid was dried, 0.37 g of the target black powder was obtained. The following shows the synthetic scheme (B).

[0162] [Chemical formula]

[0163] [FT-IR analysis] In the above Synthesis Example 1, in order to confirm that the graphene compound was chemically modified, FT -IR analysis (Fourier transform infrared spectroscopy) was performed.

[0164] FT-IR analysis was performed on three samples: the chemically modified graphene compound (Sample 1) prepared in Synthesis Example 1 above, the chemically modified graphene compound (Sample 2) prepared in Synthesis Example 2 above, and unmodified graphene oxide (Comparative Sample 1). The measurement was carried out using "Nicolet NEXUS 67 manufactured by Thermo SCIENTIFIC

[0165] ​​FT-IR analysis was performed using the ATR method (attenuated total reflectance measurement method) using 0.0. Sample 1 and Sample 2 Since the film was formed when the synthesis was completed, the ATR prism was placed on the sample. The comparative sample 1 was powdered, but the ATR was also applied from above the sample. The prism was pressed and placed into the analyzer.

[0166] Measurement range is 700cm -1 From 4000cm -1 resolution is 4.0cm -1 , scan Scan count: 256 (background scan count: 256), mirror speed: 0.6329 went.

[0167] The measurement results are shown in Figure 4. Figure 4(A) shows the results of sample 1, Figure 4(B) shows the results of sample 2, and Figure 4(C) shows the results of sample 3. 1 is an FT-IR spectrum of Comparative Sample 1.

[0168] For unmodified graphene oxide (comparison sample 1), the spectrum in Figure 4(C) shows C = The peak (1720 cm) that is thought to be attributed to the O stretching vibration -1 (near C=C stretching vibration) Possible peak (1620cm -1 (nearby), has been observed. The FT-IR spectrum of unmodified graphene oxide was confirmed.

[0169] On the other hand, in the chemically modified graphene compounds (samples 1 and 2), as shown in Figure 4(A), As shown in Figure 4(B), a peak (290 0cm -1 The observed vibrations are attributed to the CO stretching vibration and the COC antisymmetric stretching vibration. Possible peak (1100cm -1 (nearby) has also been observed. Unlike the spectrum, peaks thought to be derived from groups containing ether bonds were observed. Ta.

[0170] Therefore, it was confirmed that Sample 1 and Sample 2 were chemically modified with a group having an ether bond. As described above, the production of a chemically modified graphene compound according to one embodiment of the present invention was confirmed. We were able to confirm this. [Explanation of symbols]

[0171] 100 Positive electrode current collector 101 Cathode active material layer 102 Negative electrode current collector 103 Negative electrode active material layer 104 Solid electrolyte layer 110 Lithium-ion battery 207 Exterior body 1700 curved surface 1701 Plane 1702 Curve 1703 Radius of curvature 1704 Center of curvature 1800 Center of curvature 1801 Film 1802 radius of curvature 1803 Film 1804 Radius of curvature 1805 Battery materials

Claims

1. a positive electrode active material layer, a solid electrolyte, and a negative electrode active material; the solid electrolyte has a graphene compound; The graphene compound includes graphene oxide and a chain group having a plurality of ether bonds, the graphene oxide and the chain group are bonded via a Si atom, the graphene oxide and the Si atom are bonded by one or more Si—O bonds; The number of oxygen atoms in the chain group is 2 or more and 10 or less.

2. In claim 1, A lithium ion storage battery, wherein an —OH group is further bonded to the Si atom.

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