NONAQUEOUS ELECTROLYTE, AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY USING SAME

摘要

Disclosed is a nonaqueous electrolyte which contains a nonaqueous solvent and a solute that is dissolved in the nonaqueous solvent. The nonaqueous electrolyte is characterized in that: the nonaqueous solvent contains ethylene carbonate, propylene carbonate, diethyl carbonate and a first additive; the weight ratio of the propylene carbonate (WPC) relative to the total weight of the ethylene carbonate, the propylene carbonate and the diethyl carbonate is 30-60% by weight; the ratio of the weight ratio of the propylene carbonate (WPC) to the weight ratio of the ethylene carbonate (WEC) relative to the above-described total weight, namely WPC/WEC satisfies 2.25 = WPC/WEC = 6; and the first additive contains either an unsaturated sultone and/or a sulfonic acid ester and accounts for 0.1-3% by weight of the total weight of the nonaqueous electrolyte.