Nonaqueous electrolyte for secondary battery and nonaqueous-electrolyte secondary battery employing the same

摘要

An object is to provide a nonaqueous electrolyte and a nonaqueous-electrolyte secondary battery which have excellent discharge load characteristics and are excellent in high-temperature storability, cycle characteristics, high capacity, continuous-charge characteristics, storability, gas evolution inhibition during continuous charge, high-current-density charge/discharge characteristics, discharge load characteristics, etc. The object has been accomplished with a nonaqueous electrolyte which comprises: a monofluorophosphate and/or a difluorophosphate; and further a compound having a specific chemical structure or specific properties.

主权项

1. A nonaqueous electrolyte composition, comprising:
(1) an electrolyte; (2) a nonaqueous solvent; and (3) a monofluorophosphate and/or a difluorophosphate: wherein: the nonaqueous solvent comprises, in an amount of 10 to 100% by mass of the nonaqueous solvent, a carbonate having a halogen atom; the carbonate having a halogen atom is a cyclic carbonate; and the monofluorophosphate and/or the difluorophosphate is present in an amount of from 0.001 to 5% by mass of the composition.