Nonaqueous electrolyte solution and electrical storage device employing same

Abstract

Provided are a nonaqueous electrolytic solution having an electrolyte salt dissolved in a nonaqueous solvent, the nonaqueous solvent including a cyclic carbonate and a linear carbonate under the following condition 1 or 2, and the nonaqueous electrolytic solution containing from 0.001 to 5% by mass of vinylsulfonyl fluoride, and an energy storage device using the same. Condition 1: The linear carbonate includes both a symmetric linear carbonate and an asymmetric linear carbonate, and the proportion of the asymmetric linear carbonate occupying in the linear carbonate is from 51 to 95% by volume. Condition 2: The cyclic carbonate includes ethylene carbonate and propylene carbonate, and the linear carbonate includes a symmetric linear carbonate. The nonaqueous electrolytic solution of the present invention is capable of improving electrochemical characteristics in the case of using an energy storage device at a high voltage and further capable of not only improving a discharge capacity retention rate after a high-voltage cycle but also inhibiting gas generation.

Dependencies are inferred from the claim text.