WO2016072158A1 - Procédé de purification de solution d'électrolyte et procédé de production de solution d'électrolyte - Google Patents

Procédé de purification de solution d'électrolyte et procédé de production de solution d'électrolyte Download PDF

Info

Publication number
WO2016072158A1
WO2016072158A1 PCT/JP2015/076382 JP2015076382W WO2016072158A1 WO 2016072158 A1 WO2016072158 A1 WO 2016072158A1 JP 2015076382 W JP2015076382 W JP 2015076382W WO 2016072158 A1 WO2016072158 A1 WO 2016072158A1
Authority
WO
WIPO (PCT)
Prior art keywords
chloride
electrolyte solution
acid
purifying
agent
Prior art date
Application number
PCT/JP2015/076382
Other languages
English (en)
Japanese (ja)
Inventor
幹弘 高橋
雅隆 藤本
寛樹 松崎
Original Assignee
セントラル硝子株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by セントラル硝子株式会社 filed Critical セントラル硝子株式会社
Publication of WO2016072158A1 publication Critical patent/WO2016072158A1/fr

Links

Classifications

    • 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
    • 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
    • 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
    • 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
    • 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
    • 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 a method for purifying an electrolyte solution used as an electrolytic solution for electrochemical devices such as lithium ion batteries, sodium ion batteries, lithium air batteries, lithium sulfur batteries, and lithium ion capacitors.
  • non-aqueous electrolyte batteries such as lithium ion batteries, lithium batteries, and lithium ion capacitors have been actively developed.
  • Metal salts (Li, Na, etc.) of ionic complexes in which Lewis acid and fluorine ions are bonded such as hexafluorophosphate anion, tetrafluoroborate anion, hexafluoroarsenate anion, have high solubility and high ion dissociation
  • hexafluorophosphate anion such as hexafluorophosphate anion, tetrafluoroborate anion, hexafluoroarsenate anion
  • hexafluoroarsenate anion have high solubility and high ion dissociation
  • it is used as a supporting electrolyte for electrochemical devices from the viewpoint of a wide potential window.
  • lithium hexafluorophosphate (hereinafter LiPF 6 ) is particularly widely used because it is less toxic than lithium hexafluoroarsenate and has higher solubility than lithium tetrafluoroborate.
  • LiPF 6 also has a major drawback that it has low thermal stability and decomposes into lithium fluoride (hereinafter LiF) and phosphorus pentafluoride (hereinafter PF 5 ) by heating.
  • LiF is deposited on the electrode surface and becomes a resistance component, thereby reducing the performance of lithium-based electrochemical devices such as lithium ion batteries.
  • PF 5 accelerates the decomposition of the electrolyte solvent due to its strong Lewis acidity.
  • an ionic complex containing fluorine may react with moisture in the air or liquid to generate hydrogen fluoride.
  • excessive hydrogen fluoride may remain or hydrogen fluoride may be by-produced.
  • hydrogen fluoride in the electrolyte causes dissolution of the electrode material and corrosion of the current collector, which in turn causes deterioration of the cycle characteristics of the battery, and further decreases in battery characteristics such as charge / discharge capacity and storage stability. Therefore, the lower the content of hydrogen fluoride, the better.
  • the concentration of hydrogen fluoride in the electrolytic solution is less than 30 ppm by mass (Patent Document 3).
  • hydrogen fluoride when removing hydrogen fluoride in the electrolyte under reduced pressure, hydrogen fluoride has a high boiling point of 19.54 ° C. due to the influence of hydrogen bonds, so it takes time to remove hydrogen fluoride. The concentration of hydrogen fluoride could not be lowered sufficiently.
  • the present invention has been made in view of the above circumstances, and removes hydrogen fluoride in an electrolyte solution used as an electrolyte solution for an electrochemical device to a low concentration in a short time compared to the conventional method. It is an object of the present invention to provide a method for purifying an electrolyte solution that can be used. Furthermore, it is more preferable that oxalic acid remaining when producing an ionic complex in which a part or all of the fluorine of LiPF 6 is replaced with oxalic acid can be removed at the same time.
  • the present inventor conducted extensive research to solve the above problems, and added a chloride purification agent to make hydrogen fluoride into hydrogen chloride, and then fluorinated purification agent and unreacted purification agent.
  • a chloride purification agent to make hydrogen fluoride into hydrogen chloride, and then fluorinated purification agent and unreacted purification agent.
  • the present invention provides the following method for purifying an electrolyte solution.
  • the first aspect of the present invention is a step of adding thionyl chloride as a purification agent to an electrolyte solution containing at least hydrogen fluoride as an impurity and having an electrolyte dissolved in a nonaqueous solvent, and reacting the impurity with the purification agent. And removing the impurities by removing hydrogen chloride as a reaction product, the fluorinated purification agent, and the unreacted purification agent, and an electrolyte solution comprising: This is a purification method.
  • an electrolyte solution containing at least hydrogen fluoride as an impurity and having an electrolyte dissolved in a non-aqueous solvent includes a carboxylic acid chloride, a sulfonate acid chloride, a sulfinate acid chloride, a silicon chloride, Adding a purification agent consisting of one or a mixture selected from the group consisting of carboxylic acid anhydrides and reacting the impurities with the purification agent while extracting the reaction product out of the reaction system; And a step of removing the impurities by removing hydrogen chloride and the fluorinated purification agent, which are substances, and the unreacted purification agent, and a method for purifying an electrolyte solution.
  • a third aspect of the present invention is a method for producing an electrolyte solution, which includes a purification step using the method for purifying an electrolyte solution according to the first or second aspect.
  • the purification method of the present invention hydrogen fluoride in a solution used as an electrolytic solution of an electrochemical device is used, thionyl chloride is used as a purification agent, or a reaction product is removed from the system during the reaction with the purification agent. By removing it, it is possible to remove it to a low concentration in a simpler process and in a shorter time than before. Further, since the specific purification agent reacts with both hydrogen fluoride and oxalic acid, hydrogen fluoride and oxalic acid can be removed simultaneously by removing the reaction product and the unreacted purification agent.
  • thionyl chloride is added as a purification agent to an electrolyte solution containing at least hydrogen fluoride as an impurity and in which the electrolyte is dissolved in a nonaqueous solvent, and the impurity is reacted with the purification agent.
  • a removal step of removing the impurities by removing hydrogen chloride as a reaction product, the fluorinated purification agent, and the unreacted purification agent is a method for purifying an electrolyte solution.
  • the electrolyte solution may contain oxalic acid as an impurity.
  • fluorinated refining agent refers to thionyl fluoride, thionyl monochloride monochloride and the like.
  • reaction product of the refining agent and oxalic acid refers to sulfur dioxide, carbon monoxide, carbon dioxide, etc. produced by the reaction of the refining agent and oxalic acid.
  • the reaction product becomes a gas and quickly exits the reaction system and can participate in the reaction. Therefore, the reverse reaction of the reaction formula does not proceed, the reaction rate of the normal reaction that is a reaction between hydrogen fluoride and thionyl chloride is increased, and the concentration of hydrogen fluoride can be rapidly reduced to a low concentration.
  • reaction products and unreacted thionyl chloride can be removed simultaneously with removal of hydrogen chloride, a separate step such as filtration is unnecessary, which is suitable for industrial purification. .
  • thionyl chloride is a liquid at normal temperature and pressure, it is liquid when added to the electrolyte solution before purification, and therefore, it is easier to add than when adding a gaseous purification agent.
  • the electrolyte contained in the solution is preferably a salt, and the cation of the salt is preferably composed of one of lithium cation, sodium cation, potassium cation, quaternary alkyl ammonium cation, or a mixture thereof. This is because these cations can be used as cations of salts contained in the electrolyte for non-aqueous electrolyte batteries.
  • the salt anion is one of a hexafluorophosphate anion, a tetrafluoroborate anion, a bis (fluorosulfonyl) imide anion, a bis (trifluoromethanesulfonyl) imide anion, a bis (difluorophosphoryl) imide anion, or a mixture thereof. It is preferable to become. This is because these anions can be used as anions of salts contained in the electrolyte for non-aqueous electrolyte batteries.
  • the salt is lithium hexafluorophosphate, sodium hexafluorophosphate, potassium hexafluorophosphate, lithium tetrafluoroborate, sodium tetrafluoroborate, potassium tetrafluoroborate, lithium bis (fluorosulfonyl) imide, bis (fluorosulfonyl) ) Sodium imide, potassium bis (fluorosulfonyl) imide, bis (trifluoromethanesulfonyl) imide lithium, sodium bis (trifluoromethanesulfonyl) imide, potassium bis (trifluoromethanesulfonyl) imide, lithium bis (difluorophosphoryl) imide, bis (difluoro) One of phosphoryl) imide sodium, potassium bis (difluorophosphoryl) imide, difluoroionic complex (2a), (2b), (2c) It is preferably made of a mixture thereof.
  • each element constituting the general formula (2) is as follows.
  • the lithium salt of the difluoroionic complex (2a) is referred to as (2a-Li).
  • A Li, Na, K or quaternary alkyl ammonium
  • A Li, Na, K or quaternary alkyl ammonium
  • A Li, Na, K or quaternary alkyl ammonium
  • A Li, Na, K or quaternary alkyl ammonium
  • non-aqueous solvent for the electrolyte solution the same non-aqueous solvent used in the synthesis method of the third embodiment described later can be used.
  • the reaction time between the impurities and the purifying agent can be appropriately selected within the range of 0.1 to 72 hours depending on the reaction rate, but occupying the apparatus for a long time leads to an increase in production cost. Is preferably 12 hours or shorter, and more preferably 6 hours or shorter. Furthermore, in order to advance the reaction of the entire system, it is preferable to stir the solution during the reaction.
  • the purification agent is preferably used in a range of 10 moles or less relative to the number of moles of free acid. Furthermore, it is preferable that the free acid and the purifying agent are in a molar ratio range of 1: 0.1 to 1:10, and in particular, the free acid and the purifying agent are in a molar ratio range of 1: 1 to 1: 5. It is preferable.
  • the addition of the purification agent, stirring, and the subsequent removal of the reaction product and the unreacted purification agent are preferably performed at a temperature of ⁇ 60 ° C. to 150 ° C., more preferably ⁇ 20 ° C. to 120 ° C. If the temperature is lower than ⁇ 60 ° C., the stirring may be insufficient due to an increase in viscosity or the reaction rate may be decreased. If the temperature is higher than 150 ° C., the dissolved electrolyte may be decomposed. In particular, the temperature at which the reaction product and the unreacted purification agent are removed is preferably ⁇ 20 ° C. to 120 ° C., which can be easily heated and cooled.
  • each process in the first embodiment of the present invention at a temperature lower than the boiling point of the purifying agent or the solvent so as not to evaporate a large amount of the purifying agent or the solvent.
  • the addition of a purifying agent, stirring, and the subsequent removal of the reaction product and unreacted purifying agent are preferably performed at 50 ° C. or lower so that the electrolyte contained in the solution does not decompose.
  • the reaction product and the unreacted purification agent are removed by a method using a vapor pressure difference. Specifically, a method of degassing under reduced pressure or an inert gas introduced into the solution is used. It is removed by the method of kicking out with it.
  • Vacuum pump, aspirator, etc. can be used for decompression. Depressurization is performed by keeping the reactor in a sealed state and then maintaining the system at a pressure lower than atmospheric pressure. At this time, a part of the nonaqueous solvent is also distilled off, so that the concentration of the electrolyte is concentrated. Since the pressure in the system varies depending on the temperature and vapor pressure of the liquid to be purified, it cannot be generally stated. However, it is preferable to maintain the vacuum in the tank at 80 kPa or less in absolute pressure. If the holding pressure exceeds 80 kPa, the reaction product in the electrolyte solution, the unreacted purification agent, etc.
  • the absolute pressure is preferably 20 kPa or more.
  • the introduction of the inert gas into the solution is performed by bubbling the solution with nitrogen gas, helium gas, neon gas, argon gas, krypton gas, or xenon gas. Note that the decompression of the reaction system and the introduction of the inert gas into the solution may be performed simultaneously.
  • a carboxylic acid chloride, a sulfonic acid chloride, a sulfinic acid chloride, a silicon chloride is added to an electrolyte solution containing at least hydrogen fluoride as an impurity and having an electrolyte dissolved in a nonaqueous solvent.
  • a purification step of an electrolyte solution comprising: a removal step of removing the impurities by removing hydrogen chloride and the fluorinated purification agent which are reaction products, and the unreacted purification agent. Is the method.
  • the same solution as in the first embodiment can be used.
  • the reaction between the hydrogen fluoride in the solution and the purifying agent, or the reaction between hydrogen fluoride and oxalic acid and the purifying agent is carried out while extracting the reaction product out of the system.
  • Hydrogen fluoride and oxalic acid can be removed by reaction decomposition.
  • the method of extracting the produced reaction product out of the system is to reduce the pressure of the reaction system or to introduce an inert gas into the solution. Depressurization and introduction of inert gas can be performed in the same manner as described above. This is because the reaction between hydrogen fluoride and the refining agent is reversible, so the generated hydrogen chloride and the fluorinated purifying agent are continuously removed from the system by reducing the pressure or introducing an inert gas.
  • reaction between oxalic acid and the refining agent is an irreversible reaction in which carbon monoxide and carbon dioxide are generated and discharged out of the system, but they are slowed down even if accelerated by reduced pressure or introduction of inert gas. It will never be done.
  • the reaction is conducted while extracting the reaction product out of the system, whereby the fluorination reaction of thionyl chloride is accelerated and the removal of hydrogen fluoride can proceed. .
  • the purification agent carboxylic acid chloride, sulfonate acid chloride, sulfinate acid chloride, silicon chloride, carboxylic acid anhydride and the like can be used.
  • the purification agents include oxalyl chloride, methyl chloroformate, ethyl chloroformate, acetyl chloride, trifluoroacetic acid chloride, trifluoromethanesulfonic acid chloride, methanesulfonic acid chloride, thionyl chloride, trimethylsilyl chloride, acetic anhydride, trifluoroacetic anhydride.
  • Carboxyl chloride, sulfonate chloride, sulfinate chloride and silicon chloride react with hydrogen fluoride to produce carboxylic acid fluoride, sulfonic acid fluoride, sulfinic acid fluoride, silicon fluoride and chloride, respectively.
  • Produce hydrogen Since each fluoride has a small atomic weight of fluorine, it has a lower boiling point than chloride and is easily removed under reduced pressure or a bubbling environment. Further, since the boiling point of hydrogen chloride is as low as ⁇ 85 ° C., it is easily removed. Similarly, since carboxylic acid anhydride and carboxylic acid are obtained by reacting with hydrogen fluoride, carboxylic acid anhydride is removed by volatilization under reduced pressure or bubbling environment.
  • acetyl chloride (boiling point 51 ° C.) reacts with hydrogen fluoride
  • hydrogen chloride (boiling point ⁇ 85 ° C.)
  • acetyl fluoride (boiling point 20 ° C.) are produced according to the following reaction formula, both of which are under reduced pressure or bubbling environment. Removed below.
  • fluorinated purification agent refers to acetyl fluoride and the like.
  • the purification agent is oxalyl chloride, methyl chloroformate, ethyl chloroformate, acetyl chloride, trifluoroacetic acid chloride, trifluoromethanesulfonic acid chloride, methanesulfonic acid chloride, thionyl chloride, it decomposes not only hydrogen fluoride but also oxalic acid And can be removed.
  • reaction product of the purification agent and oxalic acid refers to acetic acid, carbon monoxide, carbon dioxide, etc. produced by the reaction of the purification agent and oxalic acid.
  • the reaction product is reacted while being extracted out of the system, the reaction between hydrogen fluoride and the purifying agent can be accelerated, and hydrogen fluoride can be quickly removed to a low concentration. it can.
  • reaction process and the removal process method and conditions in the second embodiment are the same as those in the first embodiment.
  • the third embodiment of the present invention is a method for producing an electrolyte solution, comprising a purification step using the electrolyte solution purification method of the first or second embodiment.
  • an electrolyte solution containing an ionic complex containing fluorine such as LiPF 6
  • excess hydrogen fluoride may remain or hydrogen fluoride may be produced as a by-product, and the ionic complex containing fluorine is air.
  • an electrolyte solution containing an ionic complex containing fluorine such as after synthesizing an ionic complex containing fluorine, it may generate hydrogen fluoride by reacting with moisture in the liquid or in the liquid.
  • an electrolyte solution with less impurities such as hydrogen fluoride can be obtained.
  • the 6-coordinated ionic complex (1) represented by the general formula (1) is fluorinated with a fluorinating agent in a non-aqueous solvent to produce the difluoroionic complex (2) represented by the general formula (2).
  • the electrolyte solution of the first or second embodiment is purified.
  • a hexacoordinate ionic complex in which three bidentate ligands represented by the following general formula (1) are coordinated hereinafter referred to as a six-coordinate ionic complex
  • a difluoroionic complex represented by the following general formula (2) hereinafter sometimes referred to as difluoroionic complex (2)
  • a + is any one selected from the group consisting of metal ions, protons, and onium ions, and serves to assist ion conduction in the nonaqueous electrolyte battery.
  • metal ions protons, and onium ions
  • lithium ion, sodium ion, potassium ion, or quaternary alkyl ammonium ion is preferable.
  • the quaternary alkylammonium ion is not particularly limited, and examples thereof include trimethylpropylammonium and 1-butyl-1-methylpyrrolidinium.
  • M is any one selected from the group consisting of P, As and Sb.
  • F is a fluorine atom.
  • O is an oxygen atom.
  • Y is a carbon atom or a sulfur atom.
  • Q is 1 when Y is a carbon atom.
  • Q is 1 or 2 when Y is a sulfur atom.
  • W is a hydrocarbon group which may have a heteroatom having 1 to 10 carbon atoms or a halogen atom (in the case of 3 or more carbon atoms, a branched chain or cyclic structure can be used), or- N (R 1 ) — is represented.
  • R 1 represents a hydrogen atom, an alkali metal, a hydrocarbon group having 1 to 10 carbon atoms or a halogen atom which may have a halogen atom.
  • R 1 can take a branched chain or a cyclic structure.
  • Z is a carbon atom.
  • each element of the anion portion of the hexacoordinate ionic complex (1) and the difluoroionic complex (2) is at least one combination selected from (a), (b), and (c).
  • a fluorinating agent having a molar ratio of 1.5 to 50 moles to the 6-coordinated ionic complex (1) is added.
  • the difluoroionic complex (2) is obtained by selective fluorination with use.
  • the amount of the fluorinating agent used is preferably 1.8 to 40 mol times, more preferably 2.0 to 20 mol times.
  • an ionic fluorinating agent that generates fluoride ions when added to a non-aqueous solvent can be used.
  • an ionic fluorinating agent that generates fluoride ions when added to a non-aqueous solvent.
  • an acid or a Lewis acid may be added in addition to the fluorinating agent.
  • an acid or a Lewis acid By adding an acid or a Lewis acid, it is possible to increase the proton concentration in the reaction solution and improve the reaction rate when introducing fluorine using a fluorinating agent.
  • sulfuric acid, fluorosulfuric acid, hydrogen chloride, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, nitric acid, p-toluenesulfonic acid can be used as an acid (protic acid or Bronsted acid) other than the fluorinating agent.
  • boron trifluoride, phosphorus pentafluoride, aluminum trichloride, niobium pentachloride, trifluoromethanesulfonic acid metal salt (cations are Li, Na, K, La, Ce, Pr, Nd Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y) can be used.
  • trifluoromethanesulfonic acid, methanesulfonic acid, or trifluoroacetic acid because the effect of improving the reaction rate is great.
  • the equivalent of the acid other than the fluorinating agent or the Lewis acid is preferably 0.001 to 2.0 molar equivalents relative to the hexacoordinate ionic complex (1). If the amount of the acid other than the fluorinating agent or the Lewis acid is too small, the effect of improving the reaction rate is small. If the amount is too large, not only the cost increases but also the decomposition of the product proceeds.
  • an acid or Lewis acid By adding an acid or Lewis acid, it is possible to use other than the above acidic fluorinating agent.
  • potassium fluoride Sodium fluoride, lithium fluoride, cesium fluoride, calcium fluoride, nickel fluoride, cobalt fluoride, iron fluoride, zinc fluoride, manganese fluoride, and ammonium fluoride are preferable.
  • lithium fluoride sodium fluoride, potassium fluoride, cesium fluoride, cal fluoride Um, nickel fluoride, iron fluoride, zinc fluoride, ammonium fluoride is preferred.
  • the non-aqueous solvent used in the synthesis method described above dissolves the 6-coordinate ionic complex (1) as a raw material even in a very small amount, and does not cause a reaction with a compound in the system.
  • Those having a relative dielectric constant of 2 or more are preferable.
  • a non-aqueous solvent having no solubility it is not preferable because fluorination becomes very slow. If there is even a slight solubility, the reaction proceeds because the solubility of the target difluoroionic complex (2) is high.
  • carbonate esters, esters, ketones, lactones, ethers, nitriles, amides, sulfones and the like can be used, and not only a single solvent but also two or more kinds of mixed solvents may be used.
  • non-aqueous solvent examples include dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, butyl propionate, acetone, ethyl Methyl ketone, diethyl ketone, ⁇ -butyrolactone, ⁇ -valerolactone, tetrahydrofuran, tetrahydropyran, dibutyl ether, diisopropyl ether, 1,2-dimethoxyethane, 1,2-diethoxyethane, acetonitrile, propionitrile, N, N -Dimethylformamide, dimethyl sulfoxide, sulfolane and the like, among which a solvent having a boiling point of 120 ° C or lower is preferable,
  • the reaction temperature when introducing fluorine using a fluorinating agent is ⁇ 60 ° C. to 150 ° C., preferably ⁇ 20 to 120 ° C. Fluorine introduction does not proceed sufficiently at temperatures lower than -60 ° C, and decomposition of the 6-coordinate ionic complex (1) or difluoroionic complex (2) as a product may occur at temperatures above 150 ° C. There is sex. The range of ⁇ 20 to 120 ° C. is optimal in order to obtain a sufficient fluorine introduction rate and not cause decomposition.
  • the reaction time can be appropriately selected according to the reaction rate. However, since occupying the apparatus for a long period leads to an increase in production cost, it is preferable to set it to 72 hours or less in practice. Furthermore, in order to advance the reaction of the entire system, it is preferable to stir the solution during the reaction.
  • a pressure reducing operation in order to reduce the residual free acid concentration, and if necessary, remove the precipitate by filtration.
  • a vacuum pump, an aspirator, etc. can be used for pressure reduction operation.
  • the depressurization operation is carried out by keeping the reactor in a sealed state and then maintaining the system at a pressure below atmospheric pressure. Since the pressure in the system varies depending on the temperature and vapor pressure of the liquid to be purified, it cannot be generally stated. However, it is preferable to maintain the vacuum in the tank at 80 kPa or less in absolute pressure.
  • the absolute pressure is preferably 20 kPa or more.
  • the ligand of the six-coordinated ionic complex (1) and the difluoroionic complex (2) is oxalic acid
  • a pressure reduction operation is performed after fluorination, and a part of the solvent is distilled off to difluoro It is preferable to separate the oxalic acid deposited when the ionic complex (2) is concentrated by filtration.
  • the raw materials and products were handled in a nitrogen atmosphere with a dew point of ⁇ 50 ° C. or lower.
  • the glass reactor and fluororesin reactor used were those dried at 150 ° C. for 12 hours or more and then cooled to room temperature under a nitrogen stream having a dew point of ⁇ 50 ° C. or less.
  • test solution used in the de-free acid treatment test shown in Table 1 was prepared as a solution containing at least hydrogen fluoride as an impurity and dissolved in an electrolyte.
  • the free acid value was expressed as a value based on the salt (for example, (2a-Li) in the test solution A) by converting the molar concentration of the acid into the mass of HF.
  • the conversion rate to a difluoroionic complex (2a-Li) in which two molecules of oxalic acid are coordinated is 71.0% and the selectivity is 95.4%.
  • the residual chlorine concentration and the residual free acid concentration are difluoroion ions. And less than 100 ppm by mass and 2000 ppm by mass, respectively, based on the sex complex (2a-Li).
  • the amount of hydrogen fluoride added was 2.0 molar equivalents, 0.02 molar equivalent of trifluoromethanesulfonic acid (hereinafter TfOH) was added as an acid for accelerating the reaction, and the mixture was stirred at 0 ° C. for 24 hours.
  • TfOH trifluoromethanesulfonic acid
  • the conversion rate to the difluoroionic complex (2a-Li) was 94.2% and the selectivity was 95.2%. It was confirmed that the reaction rate was improved by proceeding the fluorination reaction in the presence of TfOH. It was.
  • Test solution B Test solution A was concentrated to a salt concentration of about 50% by mass, and the precipitated solid was removed by filtration. While stirring at a temperature of 25 ° C., 6 mass times of chloroform was added to the mass of the obtained concentrated liquid to precipitate a solid. The precipitated (2a-Li) was collected by filtration. The free acid concentration contained in (2a-Li) recovered here was less than 20 mass ppm based on (2a-Li). This (2a-Li) was dissolved in EMC to prepare a 25% by mass EMC solution. Oxalic acid (0.11 g, 1.3 mmol) was added to 100 g of this EMC solution to prepare Test Solution B containing 2,000 ppm by mass of oxalic acid in terms of HF based on (2a-Li).
  • Test solution C Test solution A was concentrated to a salt concentration of about 50% by mass, and the precipitated solid was removed by filtration. While stirring at a temperature of 25 ° C., 6 mass times of chloroform was added to the mass of the obtained concentrated liquid to precipitate a solid. The precipitated (2a-Li) was collected by filtration. The free acid concentration contained in (2a-Li) recovered here was less than 20 mass ppm based on (2a-Li). This (2a-Li) was dissolved in EMC to prepare a 25% by mass EMC solution. HF (0.05 g, 2.5 mmol) was added to 100 g of this EMC solution to prepare Test Solution C containing 2000 mass ppm of HF based on (2a-Li).
  • Test solution D Test solution A (100 g) was concentrated under reduced pressure (50 ° C., 1.3 kPa) to remove EMC. Dimethyl carbonate (hereinafter DMC) (70 g) was added to the remaining solid residue (30 g) to prepare a (2a-Li) / DMC solution having a salt concentration of about 25% by mass, and the free acid concentration was measured (2a-Li ) And 1750 mass ppm.
  • DMC Dimethyl carbonate
  • Test Solution E By changing EMC to DMC in the procedure for preparing Test Solution C described above, Test Solution E containing 2000 mass ppm of HF based on (2a-Li) was obtained.
  • Test Solution G By changing EMC to DEC in the above-described procedure for preparing Test Solution C, Test Solution G containing 2000 mass ppm of HF based on (2a-Li) was obtained.
  • Test solution H A test solution containing 500 mass ppm of HF and 1500 mass ppm of oxalic acid in terms of HF based on (2a-Li) by changing DMC to tetrahydrofuran (hereinafter THF) in the procedure for preparing test solution D described above. H was obtained.
  • Test Solution I By changing EMC to THF in the procedure for preparing Test Solution C described above, Test Solution I containing 2000 ppm by mass of HF based on (2a-Li) was obtained.
  • Test Solution K By changing EMC to AcOEt in the procedure for preparing Test Solution C described above, Test Solution K containing 2,000 ppm by mass of HF based on (2a-Li) was obtained.
  • Test solution L By changing DMC to acetonitrile (hereinafter referred to as CH 3 CN) in the procedure for preparing test solution D described above, HF is contained at 500 ppm by mass based on (2a-Li), and oxalic acid is contained at 1500 ppm by mass in terms of HF. Test liquid L was obtained.
  • Test solution M By changing EMC to CH 3 CN in the procedure for preparing test solution C described above, test solution M containing 2000 mass ppm of HF based on (2a-Li) was obtained.
  • the conversion rate and selectivity were determined by F and P-NMR, the residual chlorine concentration was determined by silver nitrate titration, and the residual free acid concentration was determined by free acid titration.
  • the conversion rate to the difluoroionic complex (2a-Na) is 94.8%, the selectivity is 96.0%, and the residual chlorine concentration and the residual free acid concentration are the same as those of the difluoroionic complex (2a-Na).
  • the standards were less than 100 mass ppm and 2000 mass ppm, respectively.
  • the obtained (2a-Na) / EMC solution was adjusted to a salt concentration of about 25% by mass to obtain Test Solution N.
  • the molar ratio of the fluoride anion to the oxalate anion was 1: 2. From this, it was found that 2000 mass ppm of free acid was derived from HF at 400 mass ppm and oxalic acid at 1600 mass ppm (converted to HF).
  • Test solution O 500 g of the ion exchange resin was weighed and immersed in a 0.1 N aqueous sodium hydroxide solution (2.5 kg), and stirred at 25 ° C. for 6 hours. The ion exchange resin was collected by filtration and washed thoroughly with pure water until the pH of the washing solution was 8 or less. Thereafter, moisture was removed by drying under reduced pressure (120 ° C., 1.3 kPa) for 12 hours. Test solution A was concentrated to a salt concentration of about 50% by mass, and the precipitated solid was removed by filtration. While stirring at a temperature of 25 ° C., 6 mass times of chloroform was added to the mass of the obtained concentrated liquid to precipitate a solid.
  • the precipitated (2a-Li) was collected by filtration.
  • the free acid concentration contained in (2a-Li) recovered here was less than 20 mass ppm based on (2a-Li).
  • This (2a-Li) 25 g, 99.4 mmol was dissolved in EMC (275 mL), 150 g of the dried ion exchange resin was added thereto, and the mixture was stirred at 25 ° C. for 6 hours. Thereafter, by removing the ion exchange resin by filtration, a (2a-Na) / EMC solution in which cations were exchanged from Li + to Na + was obtained.
  • the ratio of Na + / Li + was 99.3.
  • Test solution P LiPF 6 (25 g) was dissolved in EMC (75 g), and then HF (0.05 g, 2.5 mmol) was added to prepare a test solution P containing 2000 mass ppm of HF based on LiPF 6 .
  • Test Solution Q After dissolving NaPF 6 (25 g) in EMC (75 g), HF (0.05 g, 2.5 mmol) was added to prepare Test Solution Q containing 2000 mass ppm of HF based on NaPF 6 .
  • Test solution R LiBF 4 (25 g) was dissolved in EMC (75 g), HF (0.05 g, 2.5 mmol) was added, and a test solution R containing 2000 ppm by mass of HF based on LiBF 4 was obtained.
  • Test solution S LiFSI (25 g) was dissolved in EMC (75 g), and then HF (0.05 g, 2.5 mmol) was added to prepare test solution S containing 2000 mass ppm of HF based on LiFSI.
  • Test solution T LiDFPI (25 g) was dissolved in EMC (75 g), and then HF (0.05 g, 2.5 mmol) was added to prepare test solution T containing 2000 mass ppm of HF based on LiDFPI.
  • each test solution is shown in Table 1.
  • Table 1 PF 6 represents a hexafluorophosphate anion
  • BF 4 represents a tetrafluoroborate anion
  • FSI represents a bis (fluorosulfonyl) imide anion
  • DFPI represents a bis (difluorophosphoryl) imide anion.
  • each test solution containing an ionic complex should be based on the ionic complex, since an ionic complex is often contained in the electrolytic solution by several% to several tens of%. It is necessary to make the hydrogen fluoride concentration about 1000 ppm by mass or less.
  • Example 1-1 To test solution A (100 g), thionyl chloride (0.36 g, 3.0 mmol, 1.2 eq. With respect to 2000 mass ppm of free acid converted to HF) was added as a purification agent, and the mixture was stirred at a temperature of 25 ° C. for 6 hours. Went. Thereby, hydrogen fluoride and thionyl chloride were converted into highly volatile hydrogen chloride and thionyl fluoride by the reaction. Thereafter, the reaction product was removed by reducing the pressure at a temperature of 20 to 40 ° C. and an absolute pressure of 50 to 80 kPa. At the same time, 25 g of EMC was distilled off to concentrate the ionic complex. As a result of measuring the free acid concentration, the value in terms of HF based on (2a-Li) was 200 ppm by mass.
  • Example 1-2 Except for changing the temperature from 25 ° C. to 40 ° C., the same procedure as in Example 1-1 was performed. As a result, the free acid concentration was less than 100 mass ppm.
  • Example 1-3 The procedure was the same as in Example 1-1, except that the temperature was changed from 25 ° C. to 40 ° C., the stirring time was changed from 6 hours to 3 hours, and dry nitrogen gas (10 mL / min) was continuously blown into the solution during the stirring. As a result of the treatment, the free acid concentration was less than 100 ppm by mass.
  • Example 1-4 Thionyl chloride (0.36 g, 3.0 mmol, 1.2 eq. With respect to 2000 mass ppm of free acid converted to HF) was added to test solution A (100 g), and the pressure was 50 to 80 kPa at 40 ° C. and absolute pressure. The mixture was depressurized to 3 hours and stirred. The pressure was restored to atmospheric pressure with nitrogen, and 5 g of EMC was added to restore the initial test solution weight to 100 g. Thereafter, concentration was performed under reduced pressure at a temperature of 20 to 40 ° C. and an absolute pressure of 50 to 80 kPa, and 25 g of EMC was distilled off. As a result of measuring the free acid concentration, the value in terms of HF based on (2a-Li) was less than 100 mass ppm.
  • Example 1-5 The test solution B was used and the treatment was performed in the same procedure as in Example 1-2, except that the stirring time was changed from 6 hours to 3 hours. As a result, the free acid concentration was less than 100 ppm by mass.
  • Example 1-6 The treatment was performed in the same procedure as in Example 1-2 except that the test solution C was used and the stirring time was changed from 6 hours to 3 hours. As a result, the free acid concentration was 600 ppm by mass.
  • Example 1-7 As a result of processing in the same procedure as Example 1-6 except that the addition amount of thionyl chloride was changed to 0.59 g, 5.0 mmol (2.0 eq. Relative to 2000 mass ppm of free acid in terms of HF), The free acid concentration was 200 ppm by mass.
  • Example 1-8 As a result of performing the same procedure as in Example 1-4 except that the amount of thionyl chloride added was changed to 0.59 g and 5.0 mmol using Test Solution C, the free acid concentration was less than 100 ppm by mass. became.
  • test solution A 100 g was stirred at a temperature of 40 ° C. for 3 hours while continuously blowing dry nitrogen gas (10 mL / min) into the solution. Thereafter, vacuum concentration was performed at a temperature of 20 to 40 ° C., and 25 g of EMC was distilled off. As a result of measuring the free acid concentration, it was 2000 mass ppm.
  • Test solution A 100 g was stirred at a temperature of 40 ° C. for 3 hours while keeping the pressure in the container at a reduced pressure (50 to 80 kPa). Thereafter, vacuum concentration was performed at a temperature of 20 to 40 ° C., and 25 g of EMC was distilled off. As a result of measuring the free acid concentration, the value in terms of HF based on (2a-Li) was 1900 mass ppm.
  • Test solution C 100 g containing hydrogen fluoride but containing almost no oxalic acid was stirred at a temperature of 40 ° C. for 3 hours while keeping the pressure in the container at a reduced pressure (50 to 80 kPa). Thereafter, vacuum concentration was performed at a temperature of 20 to 40 ° C., and 25 g of EMC was distilled off. As a result of measuring the free acid concentration, the value in terms of HF based on (2a-Li) was 1700 ppm by mass.
  • Example 2-1 To test solution D (100 g), thionyl chloride (0.36 g, 3.0 mmol, 1.2 eq. With respect to 2000 mass ppm of free acid converted to HF) was added, and the pressure was reduced to 40 ° C. and pressure 50 to 80 kPa. For 3 hours. The pressure was returned to atmospheric pressure with nitrogen, and DMC corresponding to the weight reduced by distillation during the operation was added to return the initial test solution weight to 100 g. Thereafter, concentration under reduced pressure was performed at a temperature of 20 to 40 ° C., and 25 g of DMC was distilled off. As a result of measuring the free acid concentration, the value in terms of HF based on (2a-Li) was less than 100 mass ppm.
  • Example 2-2 To test solution E (100 g), thionyl chloride (0.59 g, 5.0 mmol, 2.0 eq. With respect to 2000 mass ppm of free acid converted to HF) was added, and the pressure was reduced to 40 ° C. and pressure 50 to 80 kPa. For 3 hours. The pressure was returned to atmospheric pressure with nitrogen, and DMC corresponding to the weight reduced by distillation during the operation was added to return the initial test solution weight to 100 g. Thereafter, concentration under reduced pressure was performed at a temperature of 20 to 40 ° C., and 25 g of DMC was distilled off. As a result of measuring the free acid concentration, the value in terms of HF based on (2a-Li) was less than 100 mass ppm.
  • Example 2-3 Except that the test solution used was changed to F and DMC was changed to DEC, the results were processed in the same procedure as in Example 2-1. As a result, the free acid concentration (the same HF equivalent value as above) was less than 100 ppm by mass. It was.
  • Example 2-4 As a result of processing in the same procedure as in Example 2-2 except that the test solution used was changed to G and DMC was changed to DEC, the free acid concentration (the same HF equivalent value as above) was less than 100 ppm by mass. It was.
  • Example 2-5 Except that the test solution used was changed to H and DMC was changed to THF, the same procedure as in Example 2-1 was performed. As a result, the free acid concentration (the same HF equivalent value as above) was less than 100 ppm by mass. It was.
  • Example 2-6 Except that the test solution used was changed to I and DMC was changed to THF, the same procedure as in Example 2-2 was performed. As a result, the free acid concentration (the same HF equivalent value as above) was less than 100 ppm by mass. It was.
  • Example 2-7 As a result of performing the same procedure as in Example 2-1, except that the test solution to be used was J and DMC was changed to AcOEt, the free acid concentration (the same HF equivalent value as above) was less than 100 ppm by mass. It was.
  • Example 2-8 As a result of processing in the same procedure as Example 2-2 except that the test solution used was changed to K and DMC was changed to AcOEt, the free acid concentration (the same HF equivalent value as above) was less than 100 ppm by mass. It was.
  • Example 2-9 As a result of processing in the same procedure as in Example 2-1, except that the test solution used was changed to L and DMC was changed to CH 3 CN, the free acid concentration (the same HF equivalent value as above) was less than 100 ppm by mass. It became.
  • Example 2-10 Except that the test solution used was changed to M and DMC was changed to CH 3 CN, the treatment was performed in the same procedure as in Example 2-2. As a result, the free acid concentration (the same HF equivalent value as above) was 100 ppm by mass. became.
  • Examples 1-1 to 1-8, Comparative Examples 1-1 to 1-5, and Examples 2-1 to 2-10 are shown in Table 2.
  • SOCl 2 represents thionyl chloride and AcCl represents acetyl chloride.
  • Example 1-1 The treatment with 1.2 molar equivalents of thionyl chloride at 25 ° C. for 6 hours reduced the free acid to 200 mass ppm (Example 1-1), and the temperature was further raised to 40 ° C. to reduce the free acid to less than 100 mass ppm. (Example 1-2). Further, the treatment with thionyl chloride was carried out under reduced pressure, or nitrogen was introduced to improve the rate of liberated acid, and the free acid became less than 100 ppm by mass at 40 ° C. for 3 hours (Example 1 3, 1-4).
  • the free acid concentration is the same 2000 mass ppm, but when the main component is oxalic acid, the residual free acid concentration is reduced to less than 100 ppm under conditions of 1.2 molar equivalents of thionyl chloride and 3 hours at 40 ° C.
  • the main component having a free acid concentration of 2000 mass ppm is HF
  • the free acid is only reduced to 600 mass ppm under the conditions of 1.2 molar equivalents of thionyl chloride at 40 ° C. for 3 hours.
  • Example 1-6 By increasing thionyl chloride to 2.0 molar equivalents, the free acid can be increased to 200 ppm by mass (Example 1-7). Further, by using 2.0 molar equivalents of thionyl chloride and treating under reduced pressure, the free acid can be increased to 100 masses. It could be reduced to less than ppm (Example 1-8).
  • Example 3-1 As a result of carrying out the treatment in the same procedure as in Example 1-4 except that the test solution to be used was changed to N, the free acid concentration (the same HF equivalent value as above) was less than 100 ppm by mass.
  • Example 3-2 As a result of carrying out the treatment by the same procedure as in Example 1-8 except that the test solution to be used was changed to O, the free acid concentration (the same HF equivalent value as described above) was less than 100 mass ppm.
  • Example 3-3 As a result of performing the treatment in the same procedure as in Example 1-8 except that the test solution used was changed to P, the free acid concentration (the same HF equivalent value as described above) was less than 100 mass ppm.
  • Example 3-4 As a result of carrying out the treatment by the same procedure as in Example 1-8 except that the test solution used was changed to Q, the free acid concentration (the same HF equivalent value as described above) was less than 100 mass ppm.
  • Example 3-5 As a result of performing the treatment in the same procedure as in Example 1-8 except that the test solution used was changed to R, the free acid concentration (the same HF equivalent value as described above) was less than 100 mass ppm.
  • Example 3-6 As a result of performing the same procedure as in Example 1-8 except that the test solution used was changed to S, the free acid concentration (the same HF equivalent value as described above) was less than 100 ppm by mass.
  • Example 3-7 As a result of performing the treatment in the same procedure as in Example 1-8 except that the test solution used was changed to T, the free acid concentration (the same HF equivalent value as described above) was less than 100 mass ppm.
  • Example 4-1 Treatment with the same procedure as in Example 1-4 except that acetyl chloride (0.24 g, 3.0 mmol, 1.2 eq. Relative to the free acid) was used instead of thionyl chloride.
  • acetyl chloride (0.24 g, 3.0 mmol, 1.2 eq. Relative to the free acid) was used instead of thionyl chloride.
  • the same HF conversion value as above was less than 100 mass ppm.
  • Example 4-2 Treatment with the same procedure as in Example 1-8 except that acetyl chloride (0.39 g, 5.0 mmol, 2.0 eq. Relative to the free acid) was used instead of thionyl chloride.
  • acetyl chloride (0.39 g, 5.0 mmol, 2.0 eq. Relative to the free acid) was used instead of thionyl chloride.
  • the same HF conversion value as above was less than 100 mass ppm.
  • Example 4-3 Treatment with the same procedure as in Example 1-4 except that oxalyl chloride (0.38 g, 3.0 mmol, 1.2 eq. With respect to the free acid) was used instead of thionyl chloride.
  • oxalyl chloride (0.38 g, 3.0 mmol, 1.2 eq. With respect to the free acid) was used instead of thionyl chloride.
  • the same HF conversion value as above was less than 100 mass ppm.
  • Example 4-4 Treatment with the same procedure as in Example 1-8 except that oxalyl chloride (0.63 g, 5.0 mmol, 2.0 eq. Relative to the free acid) was used instead of thionyl chloride.
  • oxalyl chloride (0.63 g, 5.0 mmol, 2.0 eq. Relative to the free acid) was used instead of thionyl chloride.
  • the same HF equivalent value as above was 150 ppm by mass.
  • Example 4-5 Treatment with the same procedure as in Example 1-4 except that methyl chloroformate (0.28 g, 3.0 mmol, 1.2 eq. Relative to the free acid) was used instead of thionyl chloride.
  • the concentration (the same HF equivalent value as described above) was less than 100 ppm by mass.
  • Example 4-6 Treatment with the same procedure as in Example 1-8 except that methyl chloroformate (0.47 g, 5.0 mmol, 2.0 eq. Relative to the free acid) was used instead of thionyl chloride.
  • the concentration (the same HF equivalent value as described above) was 100 mass ppm.
  • Example 4-7 As a result of treatment in the same procedure as Example 1-4, except that trifluoromethanesulfonic acid chloride (0.51 g, 3.0 mmol, 1.2 eq. Relative to the free acid) was used instead of thionyl chloride,
  • the free acid concentration (the same HF equivalent value as described above) was less than 100 ppm by mass.
  • Example 4-8 As a result of treatment in the same procedure as Example 1-8, except that trifluoromethanesulfonic acid chloride (0.84 g, 5.0 mmol, 2.0 eq. Relative to the free acid) was used instead of thionyl chloride, The free acid concentration (same HF equivalent value as above) was 100 mass ppm.
  • Example 4-9 As a result of treatment in the same procedure as in Example 1-4, except that methanesulfonic acid chloride (0.34 g, 3.0 mmol, 1.2 eq. With respect to the free acid) was used instead of thionyl chloride, the result was free.
  • the acid concentration (the same HF equivalent value as described above) was less than 100 ppm by mass.
  • Example 4-10 As a result of treatment in the same procedure as in Example 1-8, except that methanesulfonic acid chloride (0.57 g, 5.0 mmol, 2.0 eq. Relative to the free acid) was used instead of thionyl chloride, the result was free.
  • the acid concentration (the same HF equivalent value as described above) was 100 mass ppm.
  • Example 4-11 The treatment with the same procedure as in Example 1-4 except that trimethylsilyl chloride (0.33 g, 3.0 mmol, 1.2 eq. With respect to the free acid) was used instead of thionyl chloride. (The same HF equivalent value as described above) was 1000 ppm by mass.
  • Example 4-12 Treatment with the same procedure as in Example 1-8 except that trimethylsilyl chloride (0.54 g, 5.0 mmol, 2.0 eq. Relative to the free acid) was used instead of thionyl chloride. (The same HF equivalent value as described above) was 100 mass ppm.
  • Examples 4-1 to 4-12 are shown in Table 4.
  • AcCl represents acetyl chloride
  • (COCl) 2 represents oxalyl chloride
  • ClCO 2 Me represents methyl chloroformate
  • TfCl represents trifluoromethanesulfonic acid chloride
  • MsCl represents methanesulfonic acid chloride
  • TMSCl trimethylsilyl chloride.
  • the residual free acid concentration after generation can be reduced to 100 mass ppm by reducing the pressure during the reaction with the purification agent, and the pressure reduction is reduced during the reaction with the purification agent.
  • the residual free acid concentration could be greatly reduced as compared with the case where the test was not performed (Comparison between Examples 4-1 and 4-2 and Comparative Examples 1-4 and 1-5).
  • the concentration of free acid after treatment was less than 100 ppm by mass when using AcCl, whereas 100 to 150 mass by using (COCl) 2 , ClCO 2 Me, TfCl, MsCl, and TMSCl. It was ppm, and a slight decrease in the effect was confirmed.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Power Engineering (AREA)
  • Electrochemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Inorganic Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • General Chemical & Material Sciences (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Secondary Cells (AREA)
  • Electric Double-Layer Capacitors Or The Like (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

La présente invention concerne un procédé de purification d'une solution d'électrolyte est caractérisé par : une étape dans laquelle un agent de purification est ajouté dans une solution qui est obtenue par dissolution d'un électrolyte dans un solvant non aqueux et contient au moins du fluorure d'hydrogène en tant qu'impureté, de sorte que l'impureté réagisse avec l'agent de purification ; et une étape dans laquelle l'impureté est éliminée par retrait du produit de réaction et de l'agent de purification n'ayant pas réagi. Le chlorure de thionyle est utilisé en tant qu'agent de purification. De plus, un chlorure d'acide carboxylique, un chlorure d'acide sulfonique, un chlorure d'acide sulfinique, le chlorure de silicium ou un anhydride d'acide carboxylique peut être utilisé en tant qu'agent de purification, et dans ce cas, le produit de réaction est extrait du système de réaction pendant la réaction entre le fluorure d'hydrogène et l'agent de purification. Selon ce procédé de purification, le fluorure d'hydrogène dans une solution d'électrolyte peut être éliminé à une concentration faible par des procédés simples en un temps plus court par rapport à des procédés conventionnels.
PCT/JP2015/076382 2014-11-05 2015-09-17 Procédé de purification de solution d'électrolyte et procédé de production de solution d'électrolyte WO2016072158A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2014225178A JP6369292B2 (ja) 2014-11-05 2014-11-05 電解質溶液の精製方法及び電解質溶液の製造方法
JP2014-225178 2014-11-05

Publications (1)

Publication Number Publication Date
WO2016072158A1 true WO2016072158A1 (fr) 2016-05-12

Family

ID=55908887

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2015/076382 WO2016072158A1 (fr) 2014-11-05 2015-09-17 Procédé de purification de solution d'électrolyte et procédé de production de solution d'électrolyte

Country Status (3)

Country Link
JP (1) JP6369292B2 (fr)
TW (1) TWI594489B (fr)
WO (1) WO2016072158A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110911755A (zh) * 2019-10-24 2020-03-24 东莞东阳光科研发有限公司 一种锂盐的除酸方法、非水电解液和电池
CN113165875A (zh) * 2018-11-16 2021-07-23 麻省固能控股有限公司 纯化的双(氟磺酰基)亚胺锂(LiFSI)产物、纯化粗制LiFSI的方法以及纯化的LiFSI产物的用途
CN114684856A (zh) * 2022-03-07 2022-07-01 中船(邯郸)派瑞特种气体股份有限公司 一种去除六氟化钨中氟化氢的方法及装置

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2018536645A (ja) 2015-10-28 2018-12-13 味の素株式会社 免疫賦活剤
JP2021057100A (ja) * 2018-01-24 2021-04-08 セントラル硝子株式会社 非水電解液電池用電解液、及びこれを用いた非水電解液電池
CN116282084A (zh) * 2023-03-22 2023-06-23 哈工大机器人集团(杭州湾)国际创新研究院 一种在全卤有机化合物中制备六氟磷酸钠的方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1092468A (ja) * 1996-09-19 1998-04-10 Central Glass Co Ltd リチウム電池用電解液及びその精製方法並びにそれを用いたリチウム電池
JP2006302591A (ja) * 2005-04-19 2006-11-02 Central Glass Co Ltd リチウムイオン電池用電解液の精製方法およびそれを用いた電池
JP2013166680A (ja) * 2012-02-17 2013-08-29 Central Glass Co Ltd ヘキサフルオロリン酸リチウム濃縮液の製造方法
JP2013251066A (ja) * 2012-05-30 2013-12-12 Central Glass Co Ltd 非水電解液電池用電解液、及びこれを用いた非水電解液電池
JP2014005269A (ja) * 2012-05-30 2014-01-16 Central Glass Co Ltd シュウ酸を配位子とする金属錯体精製物及び該金属錯体の非水溶媒精製溶液の製造方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1092468A (ja) * 1996-09-19 1998-04-10 Central Glass Co Ltd リチウム電池用電解液及びその精製方法並びにそれを用いたリチウム電池
JP2006302591A (ja) * 2005-04-19 2006-11-02 Central Glass Co Ltd リチウムイオン電池用電解液の精製方法およびそれを用いた電池
JP2013166680A (ja) * 2012-02-17 2013-08-29 Central Glass Co Ltd ヘキサフルオロリン酸リチウム濃縮液の製造方法
JP2013251066A (ja) * 2012-05-30 2013-12-12 Central Glass Co Ltd 非水電解液電池用電解液、及びこれを用いた非水電解液電池
JP2014005269A (ja) * 2012-05-30 2014-01-16 Central Glass Co Ltd シュウ酸を配位子とする金属錯体精製物及び該金属錯体の非水溶媒精製溶液の製造方法

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113165875A (zh) * 2018-11-16 2021-07-23 麻省固能控股有限公司 纯化的双(氟磺酰基)亚胺锂(LiFSI)产物、纯化粗制LiFSI的方法以及纯化的LiFSI产物的用途
CN110911755A (zh) * 2019-10-24 2020-03-24 东莞东阳光科研发有限公司 一种锂盐的除酸方法、非水电解液和电池
CN114684856A (zh) * 2022-03-07 2022-07-01 中船(邯郸)派瑞特种气体股份有限公司 一种去除六氟化钨中氟化氢的方法及装置
CN114684856B (zh) * 2022-03-07 2024-01-23 中船(邯郸)派瑞特种气体股份有限公司 一种去除六氟化钨中氟化氢的方法及装置

Also Published As

Publication number Publication date
TW201624809A (zh) 2016-07-01
JP2016091808A (ja) 2016-05-23
JP6369292B2 (ja) 2018-08-08
TWI594489B (zh) 2017-08-01

Similar Documents

Publication Publication Date Title
JP6369292B2 (ja) 電解質溶液の精製方法及び電解質溶液の製造方法
JP6595104B2 (ja) 非水系電解液の製造方法
JP4703319B2 (ja) リチウム電池に有用な高純度のリチウムのポリハロゲン化ホウ素クラスター塩
US7981388B2 (en) Process for the purification of lithium salts
KR102208181B1 (ko) 비스(플루오로설포닐)이미드 알칼리 금속염의 제조방법
EP2857408B1 (fr) Procédé de fabrication d'une solution de tétrafluoro(oxalate)phosphate
US10967295B2 (en) Processes for removing reactive solvent from lithium bis(fluorosulfonyl)imide (LiFSI) using organic solvents that are stable toward anodes in lithium-ion and lithium-metal batteries
JP6226643B2 (ja) ジフルオロリン酸リチウムの製造方法
TWI595003B (zh) Method for producing difluoride ion complex
WO2020100115A1 (fr) Procédés d'élimination de solvant réactif de bis(fluorosulfonyl)imide de lithium (lifsi) à l'aide de solvants organiques qui sont stables vis-à-vis d'anodes dans des batteries lithium-ion et lithium-métal
JP4560132B2 (ja) ジフルオロリン酸塩の製造方法
KR20120039648A (ko) 4불화붕산염의 제조 방법
JP2018188359A (ja) ジスルホニルアミド塩の顆粒または粉末
CN112707418A (zh) 一种六氟磷酸锂的制备方法
KR20210092226A (ko) 정제된 리튬 비스(플루오로설포닐)이미드 (LiFSI) 생성물, 미정제 LiFSI의 정제 방법, 및 정제된 LiFSI 생성물의 용도
JP2016008145A (ja) フルオロ硫酸リチウムとそれを含む溶液、およびその製造方法
CN113912028B (zh) 一种双氟磺酰亚胺的纯化方法
WO2023276568A1 (fr) Méthode de purification d'une solution aqueuse de sulfonylimide, méthode de production d'un électrolyte non aqueux et méthode de production d'une composition d'électrolyte
CN116873895A (zh) 一种二氟磷酸盐的制备方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15856319

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 15856319

Country of ref document: EP

Kind code of ref document: A1