Patent ID: 6861175

Claim:
A nonaqueous electrolyte comprising a nonaqueous solvent and a solute dissolved in said nonaqueous solvent, wherein said nonaqueous solvent contains a main solvent including 20 to 50% by volume of ethylene carbonate and 40 to 80% by volume of γ-butyrolactone and third solvent comprising a solvent P including at least one selected from the group consisting of ethylene sulfite, phenylethylene carbonate, catechol carbonate and vinylethylene carbonate, and a solvent Q including at least one selected from the group consisting of propylene carbonate, vinylene carbonate, diethyl carbonate, dimethyl carbonate, ethyl methyl carbonate, γ-valerolactone, methyl propionate and ethyl propionate; and wherein a content of the third solvent in the nonaqueous solvent falls within a range of 0.01 to 5% by weight.