Non-Aqueous Secondary Battery

A non-aqueous secondary battery comprising an electrolyte liquid comprising a supporting salt and a non-aqueous electrolyte solvent,

• wherein the non-aqueous electrolyte solvent comprises a sulfone compound represented by the following formula (1) and a fluorine-containing ester compound represented by the following formula (A);
• a content of the sulfone compound in the non-aqueous electrolyte solvent is 20 vol % or more and 70 vol % or less;
• and
• a content of the fluorine-containing ester compound in the non-aqueous electrolyte solvent is 20 vol % or more and 60 vol % or less:
• wherein, R1 and R2 each independently denote a substituted or non-substituted alkyl group, and a carbon atom of R1 and a carbon atom of R2 may bond to each other through a single bond or a double bond to form a cyclic structure;
• and
• wherein, Ra and Rb each independently denote an alkyl group or a fluorine-substituted alkyl group, and at least one of Ra and Rb is a fluorine-substituted alkyl group.