| abstract |
Disclosed is a secondary battery which has improved cycle characteristics. Specifically disclosed is a secondary battery which comprises a positive electrode (21), a negative electrode (22) and an electrolyte solution. In the secondary battery, a separator (23), which is arranged between the positive electrode (21) and the negative electrode (22), is impregnated with the electrolyte solution. The electrolyte solution contains a solvent and an electrolyte salt, and the solvent contains a cyclic compound having a disulfonic acid anhydride group (-S(=O)2-O-S(=O)2-) and succinonitrile. When compared with cases where the solvent does not contain both a cyclic compound having a disulfonic acid anhydride group and succinonitrile, or cases where the solvent contains either a cyclic compound having a disulfonic acid anhydride group or succinonitrile, the chemical stability of the electrolyte solution is improved, and thus decomposition of the electrolyte solution is suppressed even when charging and discharging are repeated. |