METHOD FOR PRODUCING DIFLUOROPHOSPHATE, NON-AQUEOUS ELECTROLYTE FOR SECONDARY CELL AND NON-AQUEOUS ELECTROLYTE SECONDARY CELL

摘要

A difluorophosphate effective as an additive for a non-aqueous electrolyte for a secondary cell can be produced in a simple manner by the use of an inexpensive material for general purpose use. A difluorophosphate is produced by reacting lithium hexafluorophosphate with a carbonate in a non-aqueous solvent. Further, the present invention includes a non-aqueous electrolyte for a secondary cell which comprises a non-aqueous solvent and, as electrolytic lithium salts, at least a hexafluorophosphate and further a difluorophosphate dissolved therein, wherein at least a part of the difluorophosphate is supplied as a liquid reaction product containing the difluorophosphate formed by reacting lithium hexafluorophosphate and a carbonate in a non-aqueous solvent.