Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
  • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
  • H01M10/0566—Liquid materials
  • H01M10/0567—Liquid materials characterised by the additives
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/54—Electrolytes
  • H01G11/58—Liquid electrolytes
  • H01G11/60—Liquid electrolytes characterised by the solvent
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/22—Electrodes
  • H01G11/26—Electrodes characterised by their structure, e.g. multi-layered, porosity or surface features
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/54—Electrolytes
  • H01G11/56—Solid electrolytes, e.g. gels; Additives therein
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/54—Electrolytes
  • H01G11/58—Liquid electrolytes
  • H01G11/62—Liquid electrolytes characterised by the solute, e.g. salts, anions or cations therein
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/54—Electrolytes
  • H01G11/58—Liquid electrolytes
  • H01G11/64—Liquid electrolytes characterised by additives
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/84—Processes for the manufacture of hybrid or EDL capacitors, or components thereof
  • H01G11/86—Processes for the manufacture of hybrid or EDL capacitors, or components thereof specially adapted for electrodes
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/052—Li-accumulators
  • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
  • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
  • H01M10/0566—Liquid materials
  • H01M10/0568—Liquid materials characterised by the solutes
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
  • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
  • H01M10/0566—Liquid materials
  • H01M10/0569—Liquid materials characterised by the solvents
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
  • H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
  • H01M4/139—Processes of manufacture
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/36—Selection of substances as active materials, active masses, active liquids
  • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
  • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/36—Selection of substances as active materials, active masses, active liquids
  • H01M4/60—Selection of substances as active materials, active masses, active liquids of organic compounds
  • H01M4/602—Polymers
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
  • H01M50/403—Manufacturing processes of separators, membranes or diaphragms
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
  • H01M50/409—Separators, membranes or diaphragms characterised by the material
  • H01M50/446—Composite material consisting of a mixture of organic and inorganic materials
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/04—Hybrid capacitors
  • H01G11/06—Hybrid capacitors with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC]
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/058—Construction or manufacture
  • H01M10/0585—Construction or manufacture of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
  • H01M2004/029—Bipolar electrodes
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M2300/00—Electrolytes
  • H01M2300/0017—Non-aqueous electrolytes
  • H01M2300/0025—Organic electrolyte
  • H01M2300/0028—Organic electrolyte characterised by the solvent
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M2300/00—Electrolytes
  • H01M2300/0017—Non-aqueous electrolytes
  • H01M2300/0065—Solid electrolytes
  • H01M2300/0068—Solid electrolytes inorganic
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M2300/00—Electrolytes
  • H01M2300/0088—Composites
  • H01M2300/0091—Composites in the form of mixtures
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/10—Energy storage using batteries

Definitions

• the present invention relates to an electrolytic solution for an electrochemical device, a plastic composition, an electrode sheet for an electrochemical device, an insulating layer for an electrochemical device, a method for producing these, and an electrochemical device.
• the electrolytic solution used as a component of the electrochemical device a so-called high-concentration electrolytic solution having an extremely high salt concentration compared to the salt concentration which was conventionally considered to be optimal is known. It has been reported that the high-concentration electrolytic solution may have effects such as improvement of withstand voltage, reduction of combustibility, improvement of transport number, etc., as compared with the conventional dilute electrolytic solution (Patent Document 1). And non-patent document 1). Therefore, when such an electrolytic solution is applied to an electrochemical device, it is expected that the effects of extending the life of the device, shortening the combustion, and increasing the potential can be obtained.
• the high-concentration electrolytic solution has an extremely high salt concentration, salting out is likely to occur, and salt crystals once formed by salting out are difficult to be redissolved. If such salting out occurs in the electrolyte in the electrochemical device and the presence of crystals is maintained without being redissolved, problems such as deterioration of electrolyte performance and damage to the device due to salt crystals may occur. .. In particular, the device may be temporarily exposed to a temperature environment well below normal temperature during transportation and storage. Further, if such salting out occurs in the electrolytic solution prior to the production of the electrochemical device, the concentration fluctuates, the fluidity decreases, and the like, which hinders the production.
• the high-concentration electrolytic solution has a higher viscosity than the conventional dilute electrolytic solution. Therefore, in manufacturing an electrochemical device, it is difficult to perform an operation such as injecting it into a gap in the housing of the device, as in the case of a conventional electrolytic solution.
• an object of the present invention is an electrochemical in which the occurrence of salting is suppressed while enjoying the advantageous effects of a high-concentration electrolytic solution such as improvement of withstand voltage, reduction of flammability, improvement of transport number, and the like. It is an object of the present invention to provide an electrolytic solution for a device, a material for constituting an electrochemical device in which such an electrolytic solution is easily available, and a method for producing the same.
• a further object of the present invention is an electrode sheet for an electrochemical device, an insulating layer for an electrochemical device, which can obtain effects such as a longer life of the device, a shorter combustion, and a higher potential, and can be easily manufactured.
• the purpose is to provide a manufacturing method and an electrochemical device.
• a high-concentration electrolytic solution containing such a polymer will have a higher viscosity, and as a solution to this, the present inventor further uses such a high-concentration electrolytic solution as a solid substance such as an active material.
• the idea was to mix with and to make a plastic composition. That is, in the production of a component of a device such as an electrode, the plastic composition can be easily manufactured by molding the plastic composition into a desired component shape. Based on these findings, the present inventor has completed the present invention. That is, the present invention is as follows.
• the content ratio of the solvent (SO) to 1 mol of the cation (C) is 0.5 to 4 mol.
• An electrolytic solution in which the content ratio of the polymer (P) is 0.5% by mass or more.
• the electrolytic solution according to [1] which has a viscosity of 500 cP or more.
• the anion (A) is, (B (R X) n1 -F) - consisting of and mixtures thereof -, (P (R X) n2 -F) -, (B (R X) n3) Contains anions selected from the group RX is a monovalent group or a divalent group which may be the same or different from each other when there are a plurality of RX.
• the monovalent group is a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, or a monovalent organic ether group.
• the divalent group is an alkylene group, an alkenylene group, an alkynylene group, a divalent organic ether group or an oxo group.
• the alkyl group, alkenyl group, alkynyl group, monovalent organic ether group, alkylene group, alkenylene group, alkynylene group, and divalent organic ether group may be substituted with a halogen atom or an oxo group.
• n1 when R X are all monovalent is 3, if the other is one of R X is a bivalent is monovalent is 2, n2, when R X are all monovalent is 5, when the other is one of R X is a bivalent is monovalent is 4, is a two divalent among R X Other Is 3 if is monovalent, n3, when R X are all monovalent is 4, when the other is one of R X is a bivalent is monovalent is 3, when two of R X is divalent Is 2, The electrolytic solution according to [3].
• the anion (A) is, PF 6 -, BF 4 -, difluoro (oxalato) borate ion, bis (oxalato) borate ion, and an anion selected from the group consisting of mixtures, in [4] The electrolyte described.
• the solvent (SO) is trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, trimethyl phosphite, triethyl phosphite, tripropyl phosphite, tributyl phosphite, phosphoric acid.
• the method for producing an electrolytic solution according to any one of [1] to [9]. A production method comprising a step of dissolving one or more kinds of materials containing the cation (C) and the anion (A) and the polymer (P) in the solvent (SO).
• the anion (A) includes a first anion (A1) and a second anion (A2).
• the first anion (A1) is an anion having the largest molar content in the anion (A).
• the second anion (A2) is an anion in the anion (A) having the second largest molar content after the first anion.
• the step according to [10] which comprises a step of adding a salt containing the second anion (A2) to the solvent (SO), and then a step of adding a salt containing the first anion (A1).
• Production method. [12] [10] or [11], which comprises dissolving the salt containing the cation (C) and the anion (A) in the solvent (SO) and then distilling off the solvent (SO). ]
• the manufacturing method described in. [13] A plastic composition for an electrochemical device, which comprises the electrolytic solution and the solid matter according to any one of [1] to [9] and has plasticity.
• the solid contains a particulate solid and a fibrous substance, and the fibrous substance exists in a state of bridging the particles of the particulate solid [13] to [19].
• a method for producing an electrode sheet for an electrochemical device which comprises molding the plastic composition according to any one of [13] to [20] into the shape of the electrode sheet.
• a method for producing an insulating layer for an electrochemical device which comprises molding the plastic composition according to any one of [13] to [20] into the shape of the insulating layer.
• An electrochemical device comprising the electrode sheet for an electrochemical device according to [21], the insulating layer for an electrochemical device according to [22], or both.
• the electrochemical device according to [25] which is a bipolar type.
• an electrochemical device in which the occurrence of salting is suppressed while enjoying the advantageous effects of a high-concentration electrolytic solution such as improvement of withstand voltage, reduction of flammability, improvement of transport number, and the like.
• a high-concentration electrolytic solution such as improvement of withstand voltage, reduction of flammability, improvement of transport number, and the like.
• an electrolytic solution a plastic composition for constructing an electrochemical device in which such an electrolytic solution is easily available, and a method for producing the same.
• the electrode sheet for an electrochemical device the insulating layer for an electrochemical device, and the like, which can obtain the effects of extending the life of the device, shortening the combustion, and increasing the potential, and can be easily manufactured, and the like. Manufacturing methods and electrochemical devices are provided.
• the electrolytic solution of the present invention is an electrolytic solution for an electrochemical device containing a specific cation (C), an anion (A), a specific solvent (SO), and a specific polymer (P).
• the cation (C) is a mono-trivalent metal ion. That is, the cation (C) can be one or more types of monovalent metal ions, one or more types of divalent metal ions, one or more types of trivalent metal ions, or a combination thereof.
• the cation (C) may exist in the electrolytic solution in an ionization equilibrium with the anion (A).
• the cation (C) can form a salt with the anion (A), but is usually in the solvent (SO) under temperature and pressure conditions from the production of the electrolyte to the production of the electrochemical device using it. , At least a part thereof is a compound that can be kept in a dissolved state without salting out.
• it can be a compound capable of maintaining a state in which at least 1% by mass is dissolved in a solvent (SO) at normal temperature and pressure, for example, 25 ° C. and 1 atm.
• a solvent SO
• cation C
• examples of the cation (C) include cations contained in various known salts that can be used in electrolytes for electrochemical devices.
• the cation (C) is preferably an ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, aluminum ions, and combinations thereof.
• alkali metal ions include Li + , Na + , K + , and Cs + .
• alkaline earth metal ions include Mg 2+ and Ca 2+ .
• Li + , Mg 2+ and a combination thereof are preferable, and a combination of Li + and Li + and Mg 2+ is more preferable.
• the electrolytic solution of the present invention may contain a cation other than the cation (C).
• the ratio of the cation (C) in the entire electrolytic solution is preferably 2.5 mol / L or more in order to exhibit the effect as the electrolytic solution.
• the upper limit of the ratio of the cation (C) is not particularly limited, but may be, for example, 10 mol / L or less.
• the cation (C) may contain divalent or trivalent metal ions.
• it may be preferable to contain a divalent or trivalent metal ion rather than the cation (C) being composed of only a monovalent metal ion.
• divalent and trivalent metal ions are prone to salting out.
• by adopting the configuration of the present invention as the electrolytic solution it is possible to suppress salting out while enjoying the effects of such divalent and trivalent metal ions.
• the precipitation of Li + may be suppressed to improve the cycle characteristics, or the strength of the electrode may be increased. be.
• the electrolytic solution of the present invention may contain an anion (A).
• the anion (A) may include an anion introduced into the system as a counter anion to the cation (C) and other optional components of the cation.
• anion (A) examples include anions contained in various known salts that can be used in an electrolytic solution for an electrochemical device. More specific examples include various anions containing a boron atom, a fluorine atom, a phosphorus atom, or two or more of them.
• anion contained in the anion (A), (B (R X) n1 -F) -, (P (R X) n2 -F) -, (B (R X) n3) -, and their Examples include anions selected from the group consisting of mixtures of. When these anions are used as the anions (A), the effect of reducing the corrosion of the current collector foil can be obtained.
• RX is a monovalent group or a divalent group which may be the same or different from each other when there are a plurality of RX.
• the monovalent group is a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, or a monovalent organic ether group
• the divalent group is an alkylene group, an alkenylene group, an alkynylene group, or a divalent organic ether. It is a group or an oxo group.
• alkyl group, alkenyl group, alkynyl group, monovalent organic ether group, alkylene group, alkenylene group, alkynylene group, and divalent organic ether group may be substituted with a halogen atom or an oxo group. It may be present, or a hetero atom may be interposed in a part of the chain.
• n1 when R X are all monovalent is 3, if the other is one of R X is a bivalent is monovalent is 2, n2 is R X are all monovalent case is 5, when the other is one of R X is a bivalent is monovalent is 4, when the other is two divalent of R X is monovalent is 3, n3, when R X are all monovalent is 4, when the other is one of R X is a bivalent is monovalent is 3, when two of R X is divalent Is 2.
• R X is a monovalent group, preferable examples thereof include fluorine atom, -CF 3, -C 2 F 5 , include -CN.
• RX is a divalent group
• any of the divalent bonds may have a structure bonded to a boron atom or a phosphorus atom.
• the anion having the largest molar content in the anion (A) is the first anion (A1), and the anion having the second largest molar content after the first anion (A1).
• the anion having the second largest molar content after the second anion (A2) and the second anion (A2) is called the third anion (A3), and so on.
• the first anion (A1) it is preferable to select an anion that contributes to ionic conductivity and has high ionic conductivity.
• FSI fluorosulfonyl imide ion
• TFSI bis (trifluoromethanesulfonyl) imide ion
• BF 4 - difluoro (oxalato) borate ion
• the second anion (A2) can be added in combination with the first anion (A1) for the purpose of exerting an additional effect.
• effects include suppression of corrosion of the current collector and stabilization by coating the surface of the active material.
• anions capable of exerting such an effect include BFx-based, PFx-based, difluoro (oxalate) borate ions, bisoxalate borate ions, and mixtures thereof.
• the BFx system refers to one or a mixture of two or more of various anions including a combination of one boron atom and one to four fluorine atoms in one anion, and is referred to as a PFx system.
• a PFx system refers to one or a mixture of two or more of various anions in which one anion contains a combination of one phosphorus atom and one to six fluorine atoms.
• the ratio of the anion (A) in the electrolytic solution of the present invention is not particularly limited, and may be, for example, an equal amount with respect to the cation (C) and the cation as another optional component.
• the solvent (SO) is a compound having a molecular weight of 1000 or less.
• the lower limit of the molecular weight of the solvent (SO) is not particularly limited, but may be, for example, 40 or more.
• the solvent (SO) can be water, a hetero element-containing organic compound (O), or a mixture thereof.
• the hetero element-containing organic compound (O) can preferably be a compound having no ionic group. That is, the hetero element-containing organic compound (O) can be a compound other than the compound having an ionic group.
• the compound having an ionic group is a cation or an anion, and includes a compound having a plurality of ionic groups in the molecule and betaine having a positive or negative charge.
• the solvent (SO) various compounds known to be usable as a solvent in an electrolytic solution for an electrochemical device can be used. From these, one or more compounds having the performance according to the desired application can be appropriately selected and used in combination as necessary.
• an organic solvent having a low boiling point or a mixed solvent containing an organic solvent having a low boiling point in a high ratio can be used as the solvent (SO).
• low boiling organic solvents include dimethyl carbonate, monoglime, methyl formate, methyl acetate, methyl alcohols, acetonitrile (AN), and mixtures thereof.
• At least one solvent is preferably selected from a compound (SO-S) that is solid at room temperature of 1 atm and becomes liquid when mixed with a cation (C) and an anion (A).
• SO-S a compound
• C cation
• A anion
• room temperature refers to a range of around 25 ° C., more specifically 25 ° C., and is preferably a solid even at a higher temperature.
• the melting point of the compound is preferably 5 ° C. or higher, more preferably 25 ° C.
• the ratio of the compound (SO—S) to the whole solvent (SO) is preferably 50 mol% or more, more preferably 60 mol%, further preferably 70 mol% or more, and even 100 mol%.
• Examples of compounds (SO-S) include ethylene carbonate (EC), N-methyloxazolidone, N, N-dimethylimidazolidinone, sulfolane (SL), dimethyl sulfone, malononitrile, succinonitrile, and dimethyl oxalate. Can be mentioned. Even if the compound (SO—S) is solid at room temperature, it can be dissolved by mixing with a salt to form a liquid and form an electrolytic solution.
• an organic solvent having a high boiling point and / or water, or a mixed solvent containing an organic solvent having a high boiling point and / or water in a high ratio can be used as the solvent (SO).
• the boiling point of such a high boiling point organic solvent can be preferably 130 ° C. or higher, more preferably 160 ° C. or higher, and even more preferably 200 ° C. or higher.
• the upper limit of the boiling point is not particularly limited, but may be, for example, 350 ° C. or lower.
• organic solvents having a high boiling point include ⁇ -butyrolactone, propylene carbonate, ethylene carbonate (EC), N-methyloxazolidone, N, N-dimethylimidazolidinone, dimethylsulfone (DMS), sulfolane (SL), and dimethyl.
• examples include sulfone, malononitrile, succinonitrile, dimethyl malonate, dimethyl oxalate, diglime, triglime, tetraglime, and mixtures thereof.
• a flame-retardant solvent may be used in addition to or instead of an organic solvent having a high boiling point.
• flame-retardant solvents are trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, trimethyl phosphite, triethyl phosphite, tripropyl phosphite, tributyl phosphite, phosphoric acid. Examples include triphenyl, triphenyl phosphite, and phosphazene-containing compounds. Further examples of flame-retardant solvents include substituents having substituents on some of the hydrocarbon chains of the various compounds.
• substituents include halogen atoms such as fluorine atom, chlorine atom and bromine atom.
• the flame retardant is a phosphoric acid ester or a phosphite ester
• the alkyl group is halogen-substituted because the flame retardant effect is high.
• Specific examples of the phosphazene-containing compound include monoethoxypentafluorocyclotriphosphazene, diethoxytetrafluorocyclotriphosphazene, and monophenoxypentafluorocyclotriphosphazene.
• the solvent (SO) contains a flame-retardant solvent
• the content ratio of the flame-retardant solvent to the entire solvent (SO) can be 0.5 to 20% by mass.
• the solvent (SO) comprises a cyclic carbonate.
• the irreversible capacity at the time of initial charging of the negative electrode can be obtained by containing the cyclic carbonate as the solvent (SO) in the electrolytic solution.
• the cyclic carbonate are ethylene carbonate, vinylene carbonate, vinylethylene carbonate, and compounds having a structure thereof.
• a preferable solvent examples include acetonitrile, ethyl methyl carbonate, ethylene carbonate, sulfolane, dimethyl sulfone, gamma butyrolactone, and fluoro.
• examples thereof include ethylene carbonate, succinonitrile, N-methyloxazolidone, N, N-dimethyloxazolidinone, trimethyl phosphate, and mixtures thereof.
• the electrolytic solution of the present invention may contain a liquid compound having a molecular weight of more than 1000 and less than 100,000 in addition to the solvent (SO).
• the ratio of the cation (C) in the entire electrolytic solution is preferably 2.5 mol / L or more.
• the content ratio of the solvent (SO) to the cation (C) is within a specific range. That is, the content ratio of the solvent (SO) to 1 mol of the cation (C) is 0.5 mol or more, preferably 1 mol or more, more preferably 1.5 mol or more, while 4 mol or less, preferably 3. It is 5 mol or less, more preferably 3.0 mol or less.
• the content ratio of the solvent (SO) to the cation (C) is a value larger than the lower limit, the ionic conductivity can be increased and the performance of the electrochemical device can be easily improved.
• the volatility, flame retardancy, and oxidation resistance of the electrolytic solution can be improved.
• Polymer (P) Polymer (P), a soluble polymer.
• the solubility of the polymer (P) as used herein means that the polymer (P) remains dissolved in the electrolytic solution under the temperature and pressure conditions from the production of the electrolytic solution to the production of the electrochemical device using the electrolytic solution. More specifically, when the polymer (P) is added to the solvent (SO) to prepare a solution at normal temperature and pressure, for example, 25 ° C. and 1 atm, at least 1% by mass of the polymer (P) is contained in the solution.
• a polymer can be a soluble polymer if it can be kept in a dissolved state.
• the polymer (P) has a mass average molecular weight of more than 10,000, preferably 100,000 or more, more preferably 200,000 or more, even more preferably 300,000 or more, and even more preferably 400,000 or more.
• the upper limit of the mass average molecular weight can be preferably 10 million or less, more preferably 3 million or less.
• polymer (P) examples include polyether-based polymers, acrylic-based polymers, polyacrylonitrile-based polymers, polyoxazoline-based polymers, aliphatic polycarbonate-based polymers, and mixtures thereof. More specific examples include polyethylene oxide, ethylene oxide copolymer, side chain ethylene oxide polymer, hydrin rubber, polyvinyl acetate, vinyl chloride / vinyl acetate copolymer, poly2-ethyl-2-oxazoline, and poly2.
• the polymer (P) preferably has a hetero element in the main chain.
• the main chain structure having a hetero element include -O- and -N-.
• Polymers with heteroelements in the main chain have a high affinity for the solvent (SO) and therefore tend to be soluble in the solvent (SO) in the production of electrolytes at low temperatures and with low power. It is preferable because the polymer (P) can be dissolved at a high concentration.
• preferable polymers include ethylene oxide-based polymers and oxazoline-based polymers.
• the polymer (P) is more preferably a copolymer.
• the copolymer tends to have lower crystallinity than the homopolymer, and therefore tends to be more easily dissolved in the solvent (SO) in the production of the electrolytic solution, and the polymer (P) itself tends to be It is particularly preferable because it is less likely to crystallize and precipitate in the electrolytic solution.
• preferable copolymers include, for example, a polyether-based copolymer such as an ethylene oxide-propylene oxide copolymer, and both (2-ethyl-2-oxazoline)-(2-methyl-2-oxazoline). Examples thereof include oxazoline-based copolymers such as polymers.
• the content ratio of the polymer (P) in the electrolytic solution of the present invention is 0.5% by mass or more, preferably 1% by mass or more, more preferably 2% by mass or more, preferably 40% by mass or less, more preferably. Is 20% by mass or less.
• a high salting out suppression effect can be obtained.
• a large decrease in ionic conductivity can be suppressed, and the liquid state of the electrolytic solution can be easily maintained.
• the electrolytic solution of the present invention has a viscosity of preferably 500 cP or more, more preferably 700 cP or more, while preferably 10 million cP or less, more preferably 1 million cP or less.
• a viscosity of the electrolytic solution at 25 ° C. is at least the above lower limit, a high salting out suppression effect can be obtained.
• a precipitate is formed as a result of salting out, its size can be reduced.
• such an effect is due to the impediment of solute migration during the salting out process in highly viscous solutions, resulting in precipitation without forming large clumps. It is considered to be.
• the viscosity of the electrolytic solution is at least the above lower limit, the exudation of the electrolytic solution from the electrode is suppressed, which is effective in the operation stability of the electrochemical device and the suppression of liquid leakage.
• the viscosity exceeds 700 cP, the time required for injecting liquid into the porous electrode becomes considerably long, so that an electrode manufacturing method in which the liquid injection step is not performed may be selected.
• the viscosity of the electrolytic solution is not more than the upper limit, the fluid state of the electrolytic solution can be easily maintained.
• the electrolytic solution can be used as the electrolytic solution of the present invention even if it loses its fluidity and is in a gelled state.
• the ionic conductivity of the electrolytic solution at 25 ° C. is preferably 10 -4 S / cm or more.
• the upper limit of the ionic conductivity is not particularly limited, but may be, for example, 10 -1 S / cm or less.
• the electrolytic solution has fluidity, and the viscosity may be controlled within the above range by raising the processing temperature.
• the viscosity in the present invention is defined by using an EMS viscometer (EMS-1000S, manufactured by Kyoto Electronics Industry Co., Ltd.) at a rotation speed of 1000 rpm so that the composition of the electrolytic solution does not change under closed conditions and moisture in the air does not get mixed in. Refers to the measured viscosity.
• the viscosity measured by this measuring method is basically the same as the value measured in accordance with JIS Z8803. If it is difficult to measure at the operating temperature because the viscosity of the electrolytic solution is too high, it can be seen that the viscosity at 25 ° C. is higher than that by raising the temperature to the measurement. It is also possible to measure several points at a high temperature and extrapolate to the operating temperature. If the measurement is still difficult, another viscometer compatible with high viscosity may be used to check the deviation from the viscosity measured by this device before use.
• the electrolytic solution of the present invention may be produced by any production method, but usually, one or more kinds of materials containing a cation (C) and an anion (A) in a solvent (SO), and two or more kinds of materials, and It can be produced by a production method including a step of dissolving the polymer (P).
• a production method including a step of dissolving the polymer (P).
• the material containing the cation (C) and the anion (A) it is preferable to use a salt in which these are paired from the viewpoint of ease of operation and the like.
• a salt in which these are paired include salts in which any one or more of the above-mentioned specific examples of the cation (C) and any one or more of the above-mentioned specific examples of the anion (A) are paired. Be done. The amount of salt added can be adjusted so that the relative ratio of the solvent (SO) and the cation (C) of the obtained electrolytic solution becomes a desired value.
• a salt in a crystalline state is usually used. The smaller the particle size of the crystal, the more preferable it is from the viewpoint of promoting dissolution.
• the crystal size can be preferably 5 mm or less, more preferably 1 mm or less, and even more preferably 500 ⁇ m or less.
• the size of the crystal referred to here the length in the longest direction can be adopted by observing the crystal from various angles.
• the lower limit of the crystal size is not particularly limited, but may be, for example, 0.5 ⁇ m or more.
• the order in which the solute (salt, polymer (P), etc.) is dissolved in the solvent (SO) is not particularly limited, and may be any order in which easy dissolution is achieved.
• the anion (A) includes the above-mentioned first anion (A1) (that is, the anion having the highest molar content) and the second anion (A2) (that is, the anion having the next highest molar content).
• a dilute solution may be prepared once, and then a part of the solvent may be distilled off to concentrate the concentration. That is, the time required for the salt and the polymer (P) to dissolve in the solvent (SO) at a high concentration is long, while the time required for the salt and the polymer (P) to dissolve at a low concentration is short, and the solvent can be easily distilled off. In some cases, it is possible to shorten the time required for producing the electrolytic solution by preparing a dilute solution once, distilling off a part of the solvent, and concentrating the concentration.
• the concentration of the solute in the dilute solution once prepared can be, for example, 1/20 to 1/2 of the desired concentration in the electrolytic solution, more preferably 1/15 to 1/5.
• the plastic composition of the present invention is a plastic composition for an electrochemical device containing the electrolytic solution and the solid substance of the present invention and having plasticity.
• a solid is an object that can remain solid in a plastic composition under temperature and pressure conditions during use of the electrochemical device. More specifically, it can be an object that can maintain a solid state in a plastic composition at normal temperature and pressure, for example, 25 ° C. and 1 atm.
• the plastic composition is a solid having plasticity as a whole, but in reality, it is a mixture of a solid and an electrolytic solution which is a liquid, so that it can be separated and recovered.
• the plastic composition may contain only one kind of solid matter, or may contain a plurality of kinds of solid matter.
• the plastic composition becomes a solid having plasticity as a whole by containing the solid substance and the electrolytic solution which is a liquid when not mixed with the solid substance.
• the solid may specifically include an active material and / or an inorganic solid electrolyte (SE).
• the active material is a substance that can function as an electrode active material for a positive electrode or a negative electrode in an electrochemical device.
• Specific examples of the active material include lithium oxide such as lithium cobalt oxide, graphite, activated carbon, graphene, silicon and its oxide, tin and its oxide, sulfur, an organic metal complex, MOF (Metal-Organic-Flamework), and the like.
• MOF Metal-Organic-Flamework
• the active material preferably has a particulate shape, more preferably a volume average particle diameter of 30 ⁇ m or less, and even more preferably a 20 ⁇ m or less shape.
• the lower limit of the particle size is not particularly limited, but may be, for example, 0.05 ⁇ m or more.
• the contact boundary area with other components of the plastic composition is increased, the strength of the obtained electrode can be increased, and the electrode strength is increased.
• the ability to carry out an electrochemical reaction can be enhanced.
• the volume average particle size of the active material and other particles can be measured according to JIS K8825.
• the inorganic solid electrolyte (SE) is a substance that can function as a component for enhancing the ionic conductivity of the insulating layer in the insulating layer in the electrochemical device, that is, the layer that separates the positive electrode and the negative electrode. Since the inorganic solid electrolyte (SE) is often nonflammable or has low combustibility, the higher the ratio of the inorganic solid electrolyte (SE) to the electrolytic solution, the higher the safety of the electrochemical device.
• the blending ratio of the inorganic solid electrolyte (SE) per total volume of the electrolytic solution and the inorganic solid electrolyte (SE) is preferably 10 vol% or more, more preferably 30 vol% or more, still more preferably 50 vol% or more, particularly preferably. Is 70 vol% or more.
• the upper limit of the preferable blending ratio of the inorganic solid electrolyte (SE) per the total volume of the electrolytic solution and the inorganic solid electrolyte (SE) is not particularly limited, but may be, for example, 99 vol% or less.
• the inorganic solid electrolyte include a lithium ion conductive metal oxide-based inorganic solid electrolyte (SE) and a sodium ion conductive inorganic solid electrolyte (SE).
• lithium ion conductive metal oxide-based inorganic solid electrolytes include LAGP (Li 1.5 Al 0.5 Ge 1.5 P 3 O 12 ) and LLZ (Li 7 La 3 Zr 2 O).
• Examples of sodium ion conductive inorganic solid electrolytes (SE) include ⁇ -alumina, Na 2.99 Ba 0.005 O 1 + x Cl 1-2x , and lithium ion conductive sulfide-based inorganic solid electrolytes ( SE) includes LPS (Li 7 P 3 S 11 ), LGPS (Li 10 GeP 2 S 12 ), and Li 9.54 Si 1.74 P 1.44 S 11.7 Cl 0.3 .
• Inorganic solid electrolytes (SEs) are usually crystalline solid particles with these compositions. Further examples of the inorganic solid electrolyte (SE) include crystals in which a small amount of other elements are added to the above composition, and analogs in which the above composition is slightly modified.
• the intragranular ionic conductivity of the inorganic solid electrolyte (SE) is preferably 10-5 S / cm or more, more preferably 10 -4 S / cm or more, and even more preferably 10 -3 S / cm. It is preferably 10-2 S / cm or more, and most preferably 10-2 S / cm or more.
• the upper limit of the particle within the ion conductivity of the inorganic solid electrolyte (SE) is not particularly limited, for example, be not more than 10 0 S / cm.
• the inorganic solid electrolyte (SE) preferably has a particulate shape, more preferably a volume average particle diameter of 20 ⁇ m or less, and even more preferably a shape of 10 ⁇ m or less.
• the lower limit of the volume average particle size of the inorganic solid electrolyte (SE) is not particularly limited, but may be, for example, 0.01 ⁇ m or more.
• the inorganic solid electrolyte (SE) can also be a component of a plastic composition for forming an electrode sheet.
• the inorganic solid electrolyte (SE) is suspended in the electrolytic solution, and the suspension is added as a component of the plastic composition by producing a plastic composition by mixing the suspension with other components. sell.
• the particle size of the inorganic solid electrolyte (SE) is preferably smaller than that of the active material.
• the plastic composition may further contain fibrous material.
• the fibrous material can form part of the solid in plasticity.
• the fibrous substance may also have a function of an active material or an inorganic solid electrolyte (SE).
• SE solid electrolyte
• fibrous substances include polytetrafluoroethylene fibers, cellulose nanofibers, carbon nanotubes, carbon nanofibers, and combinations thereof.
• the carbon nanotubes are particularly preferably single-walled carbon nanotubes.
• the fiber diameter of the fibrous substance is preferably nano-sized (maximum diameter is less than 1 ⁇ m).
• the average fiber diameter of the fibrous substance is preferably 0.4 nm or more, preferably 500 nm or less, and more preferably 100 nm or less.
• the assembly of the plastic composition is improved, and a molded product having excellent strength can be obtained.
• the fiber diameter can be measured using a microscope such as a scanning electron microscope or a transmission electron microscope, and the arithmetic mean can be obtained.
• polytetrafluoroethylene fiber is used as the fibrous substance, it can be molded into such a fibrous shape in the process of manufacturing the plastic composition.
• particulate polytetrafluoroethylene is added into the system, and a shearing force is further applied by kneading or the like to transform the shape into nano-sized fibers in the system. It can be transformed.
• the fiber length of the fibrous substance has a fiber length equal to or larger than the volume average particle size of a solid substance other than the fibrous substance.
• the fiber length of the fibrous substance is more preferably half or more of the average thickness of the member. It is more preferably equal to or greater than the average thickness, and may be equal to or greater than the thickness of the member.
• the solid contains a particulate solid and a fibrous substance
• the fibrous substance exists in a state of bridging the particles of the particulate solid. More specifically, when observing the electrodes of the present invention with a microscope, it is preferable that there are 10 or more bridges in a 100 ⁇ m square field of view, and more preferably 20 or more bridges. If volatile organic compounds are present and unsuitable for observation, it is preferable to perform observation after drying. By having such a bridging structure, the assembly of the plastic composition is further improved, and a molded product having further excellent strength can be obtained.
• the electrode sheet for an electrochemical device of the present invention and the insulating layer for an electrochemical device of the present invention include the plastic composition of the present invention.
• the method for producing an electrode sheet for an electrochemical device of the present invention includes molding the plastic composition of the present invention into the shape of the electrode sheet, and the method for producing an insulating layer for an electrochemical device of the present invention is described above.
• the present invention comprises molding the plastic composition of the present invention into the shape of an insulating layer.
• the electrode sheet can form an electrode by superimposing it on an appropriate layered current collector.
• a metal foil body such as a copper foil, an aluminum foil, or a stainless steel foil can be used.
• the shape of the electrode sheet and the insulating layer is not particularly limited and can be a desired shape. From the viewpoint of obtaining a small-sized and high-performance electrochemical device, the electrode sheet and the insulating layer preferably have a thin layered shape. In the case of a layered shape, the thickness is preferably 5 to 200 ⁇ m. By setting the thickness to the above lower limit or more, independence can be easily obtained. By setting the thickness to the above upper limit or less, a small and high-performance electrochemical device can be easily formed.
• the electrode sheet for an electrochemical device of the present invention and the insulating layer for an electrochemical device of the present invention preferably have independence.
• the self-supporting property means that the shape can be maintained without being torn even when it is not supported by a support such as a base film.
• the electrochemical device of the present invention includes the electrode sheet for the electrochemical device of the present invention, the insulating layer for the electrochemical device of the present invention, or both of them.
• the electrode sheet can be provided in the electrochemical device in a state in which the electrodes are formed by superimposing the electrode sheet on an appropriate layered current collector such as the one described above.
• the insulating layer may be provided between a plurality of electrodes (for example, a positive electrode and a negative electrode) in the electrochemical device.
• Examples of the electrochemical device of the present invention include primary batteries such as lithium primary batteries; lithium ion secondary batteries, lithium metal secondary batteries, sodium ion secondary batteries, potassium ion secondary batteries, magnesium secondary batteries, and aluminum secondary batteries.
• Non-aqueous secondary batteries such as secondary batteries; air batteries; solar cells such as dye-sensitized solar cells; capacitors such as electric double layer capacitors and lithium ion capacitors; electrochromic display devices; electrochemical light emitting elements; electric double layer transistors And electrochemical actuators.
• the electrochemical device of the present invention is a battery, specifically a lithium ion secondary battery. More specifically, a positive electrode current collector such as aluminum foil, a positive electrode sheet, a separator, a negative electrode sheet, and a negative electrode current collector such as copper foil are superposed in this order to form a multi-layered product constituting a battery unit. Batteries can be manufactured by inserting them into a suitable exterior, injecting electrolyte if necessary, and sealing the openings in the exterior.
• the electrode sheet or the insulating layer of the present invention is adopted as any one or more of the positive electrode sheet, the negative electrode sheet and the separator, and the electrolytic solution and the active material of the lithium ion secondary battery are used as the electrolytic solution and the active material constituting them.
• a lithium ion secondary battery can be constructed by using a material suitable for the material. Further, when the electrolytic solution is injected into the exterior, the electrolytic solution of the present invention may be used as the electrolytic solution.
• a step of advancing a reaction such as a cross-linking reaction with the polymer (P) constituting them may be performed in a step after the electrode sheets and / or the insulating layers are laminated. More specifically, after sealing the opening of the exterior, the cross-linking reaction of the polymer (P) can be allowed to proceed by applying some energy from the outside of the exterior. Examples of application of such energy include heating and irradiation of energy rays such as visible light, electron beam, and radiation. Of these, those that can be applied through the exterior can be appropriately selected. Further, in order to achieve such a cross-linking reaction, the electrolytic solution may contain a component such as a polymerization initiator that advances the cross-linking reaction of the polymer (P) in response to the application of such energy.
• a component such as a polymerization initiator that advances the cross-linking reaction of the polymer (P) in response to the application of such energy.
• the electrochemical device of the present invention is a bipolar device, and specifically, it may be a bipolar battery.
• a bipolar device is a device having electrodes having a bipolar structure.
• An electrode having a bipolar structure is an electrode in which a positive electrode material is provided on one surface of a current collector and a negative electrode agent is provided on the other surface.
• a structure in which a plurality of bipolar electrodes are stacked a structure in which a plurality of device units are stacked in series can be obtained in one device.
• a bipolar type battery may have a structure in which a plurality of battery units are stacked in series in one battery pack.
• a positive electrode current collector such as an aluminum foil, a positive electrode sheet, an insulating layer sheet, a negative electrode sheet, an intermediate foil body such as a stainless steel foil, a positive electrode sheet, and an insulating layer.
• a battery including a sheet, a negative electrode sheet, and a negative electrode current collector such as a copper foil stacked in this order can be mentioned.
• two battery units are stacked in series, but one or more combinations of "intermediate foil body such as stainless steel foil, positive electrode sheet, insulating layer sheet, negative electrode sheet" are provided. It is also possible to take a structure in which one or more battery units are stacked in series.
• LiFSI Lithium bis (fluorosulfonyl) imide (Li + (N (SO 2 F) 2 ) - )
• LiTFSI Lithium bis (trifluoromethanesulfonyl) imide (Li + (N (SO 2 CF 3 ) 2 ) - )
• LiBF 4 lithium borofluoride
• LiDFOB lithium difluoro (oxalato) borate (Li + B (R X) 3) -, two of R X is -F, 1 single is -O-CO-CO-O-)
• Mg (TFSI) 2 Magnesium bis (trifluoromethanesulfonyl) imide (Mg 2+ ((N (SO 2 CF 3 ) 2 ) - ) 2 )
• AN acetonitrile
• EMC ethyl methyl carbonate
• Precipitation was observed in all examples other than Production Example 12 and Production Example 13.
• the shape of the precipitate was an angular shape and a needle-like shape, and the dimensions were approximately 1 mm or more. Therefore, when these mixed solutions are used in an electrochemical device, it is considered that the generation of precipitates adversely affects the function of the device.
• Production Example 14 is an example in which the cation in Production Example 12 and the cation in Production Example 13 are mixed. Although precipitation was not observed in Production Example 12 and Production Example 13, precipitation was observed in Production Example 14, so that precipitation is likely to occur when a plurality of types of cations are mixed. I understand.
• step (ii) When the polymer (PA) and the polymer (PB) were used, a uniform solution was obtained by allowing to stand for 24 hours in all the examples in the step (i). On the other hand, in step (ii), a uniform solution was obtained by stirring for 30 minutes in all the examples. Furthermore, the viscosity of the obtained electrolytic solution was measured. The viscosity was measured using an EMS viscometer (EMS-1000S, manufactured by Kyoto Electronics Manufacturing Co., Ltd.) at a rotation speed of 1000 rpm so that the composition of the electrolytic solution did not change under closed conditions and moisture in the air was not mixed.
• EMS viscometer EMS-1000S, manufactured by Kyoto Electronics Manufacturing Co., Ltd.
• step (i) When the polymer (PC) was used, in any of the examples in the step (i), a transparent insoluble matter remained after standing for 24 hours. Therefore, when the mixture was allowed to stand for another 150 hours, a uniform solution was obtained. was gotten. On the other hand, in step (ii), a uniform solution was obtained by stirring for 3 hours in all the examples.
• step (i) When the polymer (PE) was used, in step (i), dissolution hardly proceeded even after standing for 24 hours, and dissolution did not proceed even after standing for 150 hours. Therefore, step (i) The electrolytic solution was not prepared by. On the other hand, in step (ii), a uniform solution was obtained by stirring for 20 hours.
• step (i) When the polymer (PD) was used, and when the polymer (PF) was used, in step (i), dissolution hardly proceeded after standing for 24 hours, and the mixture was allowed to stand for another 150 hours. However, since the dissolution did not proceed, the electrolytic solution was not prepared by the step (i). On the other hand, in step (ii), a uniform solution was obtained by stirring for 3 hours.
• Example 2 Lithium ion secondary battery
• the planetary mixer is charged with 100 parts by mass of lithium cobaltate (manufactured by Nippon Kagaku Kogyo Co., Ltd., product name "Celseed C") as an active material and 3 parts by mass of acetylene black as a conductive filler, and the solid content concentration becomes 90% by mass.
• Lithium ion secondary battery (2-1. Positive electrode)
• the planetary mixer is charged with 100 parts by mass of lithium cobaltate (manufactured by Nippon Kagaku Kogyo Co., Ltd., product name "Celseed C”) as an active material and 3 parts by mass of acetylene black as a conductive filler, and the solid content concentration becomes 90% by mass.
• N-methylpyrrolidone was added, and the mixture was stirred for 20 minutes and mixed.
• a positive electrode (grain: 10 mg / cm 2 , density 3.3 g / cm 3 ) was produced according to a general method for producing an electrode of a lithium ion battery.
• (2-2. Lithium-ion secondary battery) The positive electrode obtained in (2-1), a PTFE membrane filter having a thickness of 100 ⁇ m as a separator (manufactured by Merck, product name “Omnipore JMWP04700”), and a lithium metal foil having a thickness of 100 ⁇ m as a negative electrode are superposed in this order. , A multi-layered electrode for a lithium ion secondary battery was constructed.
• a polymer (PB) was added to this mixed solution so as to have a concentration of 0.5% by mass, and the mixture was dissolved to obtain an electrolytic solution.
• An electrode multi-layered material was inserted into an aluminum laminated exterior material for a battery, an electrolytic solution was injected, and the opening of the exterior was closed to seal the contents to obtain a lithium secondary battery.
• the obtained secondary battery When the obtained secondary battery was charged / discharged at a speed of 0.2 C in an environment of 25 ° C., it showed a discharge capacity of 140 mAh / g in a voltage range of 4.2-3.0 V, and was charged / discharged. It was possible to repeat.
• Example 3-1 Evaluation of flame retardancy
• a polymer (PA) was added to this mixed solution so as to have a concentration of 10% by mass, and the mixture was dissolved to obtain an electrolytic solution.
• the ratio of trimethyl phosphate in this electrolytic solution was 15.4% by mass.
• This electrolytic solution corresponds to a part of the DMS of the electrolytic solution of Example 1-9 replaced with TMP.
• Example 3-2 Evaluation of flame retardancy
• the same flammability evaluation as (3-1-2) of Example 3-1 was evaluated. went. It was ignited by keeping the flame on for 4 seconds. However, the fire was extinguished spontaneously 2 seconds after ignition. When the fire was extinguished and the flame was applied again, it ignited again, but it was naturally extinguished 2 seconds after the ignition as in the first time. From this, it was found that although this electrolytic solution ignites, the entire amount does not burn and exhibits self-extinguishing property.
• Example 4 Lithium-ion secondary battery using a plastic composition
• a polymer (PB) was added to this mixed solution so as to have a concentration of 5% by mass, and the mixture was dissolved to obtain an electrolytic solution.
• (4-3. Lithium-ion secondary battery) An aluminum foil with a thickness of 25 ⁇ m, a positive electrode sheet obtained in (4-2), a separator impregnated with the electrolytic solution of (4-1) (manufactured by Polypore, product name “Cellguard 2325”), and a thickness of 100 ⁇ m as a negative electrode.
• the Li metal foil and the copper foil having a thickness of 25 ⁇ m were superposed in this order to obtain an electrode multilayer product for a lithium ion secondary battery.
• the contents are vacuum-sealed by inserting the electrode multi-layered material into the aluminum-laminated exterior for batteries, degassing in vacuum for 1 minute, and then heat-sealing the opening of the exterior while maintaining the vacuum degassed state.
• a lithium ion secondary battery was manufactured. No weight loss was observed before and after the vacuum seal. Immediately after production, this battery was charged and discharged at a rate of 0.1 C in an environment of 25 ° C., and showed a discharge capacity of 140 mAh / g in the voltage range of 4.2-3.0 V, and repeated charging and discharging were repeated. It was possible. When the change in capacity was measured by repeating charging and discharging of this battery, the capacity of 90% of the initial capacity was maintained when charging and discharging were repeated up to 200 cycles.
• Example 5 Ionic conductivity of the electrolytic solution of the present invention
• the polymer (PA) was added to the electrolytic solution of the prior art prepared in Comparative Example 2 (C2-1) so as to have a concentration of 5% by mass and dissolved to prepare the electrolytic solution of the present invention. ..
• the ionic conductivity of this electrolytic solution was measured by the same measuring method as in Comparative Example 2 (C2-2). As a result, the ionic conductivity was 1.70 ⁇ 10 -3 S / cm, which was higher than that without the polymer added.
• This solid electrolyte has an ionic conductivity of 1.5 ⁇ 10 -3 S / cm or more in the uncrushed crystalline state, while the ionic conductivity of the powdered compressed product is applied at a high pressure of 10 MPa. Although it was in a compressed state, it was a low value as described above. It is considered that this is due to the incomplete contact between the powders even in such a pressurized state.
• Example 6 Ionic conductivity of an insulating layer containing an inorganic solid electrolyte powder
• 100 mg of the electrolytic solution of the present invention obtained in Example 5 and 10 mg of PTFE fiber as a fibrous substance were weighed, and in addition, the same inorganic solid electrolyte as that used in Comparative Example 3 was added to the inorganic solid in the entire composition.
• the electrolyte was weighed so as to have a volume fraction of 70% by volume, and these were kneaded well to obtain a set of clay-like plastic composition. This plastic composition had independence and plasticity.
• This plastic composition was formed into a sheet having a thickness of 200 ⁇ m, punched into a disk shape having a diameter of 12 mm, sandwiched between two disk-shaped SUS plates, and pressurized at a pressure of 0.01 MPa. This pressurized state was maintained, and the ionic conductivity at 25 ° C. was measured. The measurement was performed by the AC impedance method in the frequency range of 1M to 0.1Hz. As a result, the ionic conductivity was 2.29 ⁇ 10 -3 S / cm, which was higher than the ionic conductivity measurement result for the electrolytic solution of Example 5. From this, it is considered that the main component of ionic conduction in this system is the solid electrolyte, and the electrolytic solution acts as an improving agent for the interfacial contact property of the solid electrolyte.
• PB polymer
• This plastic composition was thinly rolled to obtain a positive electrode sheet having a thickness of 80 ⁇ m, a thickness accuracy of ⁇ 3%, and a density of 3.9 g / cm 3. Even if this sheet had a rectangular shape of 4 cm square, it could be pinched with tweezers and had high independence.
• Lithium-ion secondary battery An aluminum foil with a thickness of 25 ⁇ m, a positive electrode sheet obtained in (7-2), an insulating layer sheet obtained in (7-4), a negative electrode sheet obtained in (7-3), and copper having a thickness of 25 ⁇ m.
• the foils were superposed in this order to obtain an electrode multilayer product for a lithium ion secondary battery.
• the contents are vacuum-sealed by inserting the electrode multi-layered material into the aluminum-laminated exterior for batteries, degassing in vacuum for 1 minute, and then heat-sealing the opening of the exterior while maintaining the vacuum degassed state. Then, a lithium ion secondary battery was manufactured. No weight loss was observed before and after the vacuum seal.
• this battery was charged and discharged at a rate of 0.1 C in an environment of 25 ° C., and showed a discharge capacity of 140 mAh / g with respect to the positive electrode weight in the voltage range of 4.2-3.0 V. It was possible to repeat charging and discharging.
• Example 8 Evaluation of changes in state due to volatilization of electrolytic solution
• the polymer (PB) was added to the electrolytic solution of the prior art so as to be 5% by mass and dissolved to obtain the electrolytic solution of the present invention.
• Each of the electrolytic solution of the prior art and the electrolytic solution of the present invention was weighed in a 1 g glass dish and left in a draft of a dry room having a temperature of 18 ° C. and a dew point of ⁇ 40 ° C. or lower.
• weight loss was confirmed in both electrolytic solutions, and it was considered that 40% of acetonitrile in the electrolytic solutions had volatilized.
• the formation of crystals was confirmed in the electrolytic solution of the prior art, but not in the electrolytic solution of the present invention.
• no salt precipitation was still confirmed. From this, it was found that the electrolytic solution of the present invention is less likely to cause salt precipitation even if the solvent is reduced in the long-term use of the electrochemical device.
• Example 9 Electrochemical device having a bipolar structure
• a 25 ⁇ m thick aluminum foil, a positive electrode sheet, an insulating layer sheet, a negative electrode sheet, a 20 ⁇ m thick stainless steel foil, a positive electrode sheet, an insulating layer sheet, a negative electrode sheet, and a 25 ⁇ m thick copper foil are laminated in this order to be bipolar.
• An electrode multilayer product for a battery was obtained.
• the positive electrode sheet, the insulating layer sheet, and the negative electrode sheet include the positive electrode sheet obtained in (7-2) of Example 7, the insulating layer sheet obtained in (7-4) of Example 7, and the (7-4) of Example 7.
• the negative electrode sheet obtained in 7-3) was used.
• the manufactured bipolar battery has a configuration in which two cells are connected in series in the same exterior, and since the fluidity of the electrolytic solution is low, the electrolytic solution does not entangle inside, and 8.4 to 6 V. It was possible to charge and discharge in the voltage range up to.
• Example 10 Production of an electrolytic solution in which the second salt is dissolved first
• LiFSI as a first salt containing a first anion
• LiDFOB as a second salt containing a second anion
• a second salt of 0.5 mm Albanyl (193.8 mg) was added to ethylene carbonate 20 mm Albanyl (1.761 g) and stirred at 50 ° C. to completely dissolve.
• 9.5 mmol (1.871 g) of the first salt was added thereto and stirred, and the first salt was completely dissolved in 1 hour to obtain a mixed solution.
• the polymer (PB) was further added to and dissolved in this mixed solution so as to have a concentration of 5% by weight, and the electrolytic solution of the present invention could be obtained.
• Example 11 Production of an electrolytic solution including a step of distilling off a solvent
• An electrolytic solution having the same composition as in Example 1-2 was prepared by mixing the components at once. That is, 187.1 g (1 mol) of LiFSI, 41.1 g (1 mol) of acetonitrile, and 4.66 g of the polymer (PB) were weighed in a glass flask and stirred at room temperature. It took about 3 hours to completely dissolve the ingredients.
• the amount of acetonitrile was increased 10 times, and 187.1 g (1 mol) of LiFSI, 411 g (10 mol) of acetonitrile, and 4.66 g of the polymer (PB) were weighed in a glass flask and at room temperature. After stirring, a solution in which all the components were completely dissolved was obtained in about 15 minutes. When this solution was heated in an oil bath at 90 ° C. to distill off acetonitrile, 9 mol of acetonitrile could be distilled off after 30 minutes, and as a result, the electrolytic solution of the present invention was obtained. Was made. The total time required for dissolution and distillation was 45 minutes, and the electrolytic solution of the present invention could be produced in a shorter time.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Manufacturing & Machinery (AREA)
• Power Engineering (AREA)
• Inorganic Chemistry (AREA)
• General Physics & Mathematics (AREA)
• Condensed Matter Physics & Semiconductors (AREA)
• Physics & Mathematics (AREA)
• Materials Engineering (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Composite Materials (AREA)
• Secondary Cells (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=77490229

Family Applications (1)

Country Status (5)

Cited By (4)

Families Citing this family (4)

Citations (6)

Family Cites Families (16)

• 2021
  • 2021-02-25 JP JP2022503710A patent/JP7601086B2/ja active Active
  • 2021-02-25 CN CN202180015495.3A patent/CN115136376A/zh active Pending
  • 2021-02-25 WO PCT/JP2021/007174 patent/WO2021172456A1/ja not_active Ceased
  • 2021-02-25 US US17/904,595 patent/US12603325B2/en active Active
  • 2021-02-25 EP EP21761718.2A patent/EP4113652A4/en active Pending

Patent Citations (6)

Non-Patent Citations (2)

Also Published As

Similar Documents

Legal Events