Abstract: Disclosed is a method for forming lithium hexafluorophosphate by reacting together phosphorus trichloride, chlorine and lithium chloride in a nonaqueous organic solvent and then making the reaction product formed in the solvent react with hydrogen fluoride. This method is characterized by that a lithium hexafluorophosphate concentrated liquid is obtained by conducting a filtration after making the reaction product formed in the solvent react with hydrogen fluoride and then subjecting the filtrate to a concentration by degassing. By this method, it is possible to easily produce a high-purity, lithium hexafluorophosphate concentrated liquid at a low cost.

Abstract: An electrolyte for an electrochemical device according to the present invention has a chemical structure formula represented by a general formula (1): where M is a group 13 or 15 element of the periodic table; A+ is an alkali metal ion or an onium ion; m is a number of 1-4 when M is a group 13 element, and is a number of 1-6 when M is a group 15 element; n is a number of 0-3 when M is a group 13 element, and is a number of 0-5 when M is a group 15 element; R is a halogen atom, a C1-C10 halogenated alkyl group, a C6-C20 aryl group, or a C6-C20 halogenated aryl group; a hydrogen atom in R may be replaced with a specific substituent; and a carbon atom in R may be replaced by a nitrogen atom, a sulfur atom or an oxygen atom.

Abstract: An object of the present invention is to provide: a production method for commercially advantageously producing lithium difluorophosphate or an electrolyte solution containing the lithium difluorophosphate, the lithium difluorophosphate serving as an additive useful for improving performance of a nonaqueous electrolyte battery; and a nonaqueous electrolyte battery employing the electrolyte solution for the nonaqueous electrolyte battery which solution contains the lithium difluorophosphate produced by the production method. To provide an electrolyte solution for a nonaqueous electrolyte battery which solution contains lithium difluorophosphate, in such a manner as to produce lithium difluorophosphate in the electrolyte solution by reacting a halide other than a fluoride, LiPF6 and water in a nonaqueous solvent, the lithium difluorophosphate serving as an additive useful for improving performance of the nonaqueous electrolyte battery.

Abstract: Disclosed is a method for forming lithium hexafluorophosphate by reacting together phosphorus trichloride, chlorine and lithium chloride in a nonaqueous organic solvent and then making the reaction product formed in the solvent react with hydrogen fluoride. This method is characterized by that a lithium hexafluorophosphate concentrated liquid is obtained by conducting a filtration after making the reaction product formed in the solvent react with hydrogen fluoride and then subjecting the filtrate to a concentration by degassing. By this method, it is possible to easily produce a high-purity, lithium hexafluorophosphate concentrated liquid at a low cost.

Abstract: [Summary] An object of the present invention is to find a new electrolyte having a characteristics for the electrolyte for an electrochemical device and to provide excellent electrolytic solution for a nonaqueous electrolyte battery and nonaqueous electrolyte battery which use this. [Solving Means] To provide an electrolyte for an electrochemical device, having a chemical structure formula represented by a general formula (1). where M is a group 13 or 15 group element of the periodic table; A+ is an alkali metal ion or an onium ion; m is a number of 1-4 when M is a group 13 element, and is a number of 1-6 when M is a group 15 element; n is a number of 0-3 when M is a group 13 element, and is a number of 0-5 when M is a group 15 element; and R is a halogen atom, a C1-C10 halogenated alkyl group, a C6-C20 aryl group, a C6-C20 halogenated aryl group.

Abstract: Disclosed is a method for producing a lithium difluorobis(oxalato)phosphate solution, which is characterized by that lithium hexafluorophosphate and oxalic acid are mixed together in a nonaqueous solvent, in a manner that the molar ratio of lithium hexafluorophosphate to oxalic acid falls within a range of 1:1.90 to 1:2.10, and furthermore silicon tetrachloride is added to this, in a manner that the molar ratio of lithium hexafluorophosphate to silicon tetrachloride falls within a range of 1:0.95 to 1:1.10, thereby conducting a reaction. The lithium difluorobis(oxalato)phosphate solution produced by this method has low contents of chlorine compounds and free acids. Therefore, it can become an additive that is effective for improving performance of nonaqueous electrolyte batteries.

Abstract: Disclosed is a method for producing a lithium difluorobis(oxalato)phosphate solution, which is characterized by that lithium hexafluorophosphate and oxalic acid are mixed together in a nonaqueous solvent, in a manner that the molar ratio of lithium hexafluorophosphate to oxalic acid falls within a range of 1:1.90 to 1:2.10, and furthermore silicon tetrachloride is added to this, in a manner that the molar ratio of lithium hexafluorophosphate to silicon tetrachloride falls within a range of 1:0.95 to 1:1.10, thereby conducting a reaction. The lithium difluorobis(oxalato)phosphate solution produced by this method has low contents of chlorine compounds and free acids. Therefore, it can become an additive that is effective for improving performance of nonaqueous electrolyte batteries.

Abstract: [Problems] An object of the present invention is to provide: a production method for commercially advantageously producing lithium difluorophosphate or an electrolyte solution containing the lithium difluorophosphate, the lithium difluorophosphate serving as an additive useful for improving performance of a nonaqueous electrolyte battery; and a nonaqueous electrolyte battery employing the electrolyte solution for the nonaqueous electrolyte battery which solution contains the lithium difluorophosphate produced by the production method. [Means for Solving Problems] To provide an electrolyte solution for a nonaqueous electrolyte battery which solution contains lithium difluorophosphate, in such a manner as to produce lithium difluorophosphate in the electrolyte solution by reacting a halide other than a fluoride, LiPF6 and water in a nonaqueous solvent, the lithium difluorophosphate serving as an additive useful for improving performance of the nonaqueous electrolyte battery.