An electrolytic solution and a battery capable of improving high temperature characteristics are provided. A separator (23) is impregnated with an electrolytic solution. The electrolytic solution includes a solvent including 4,5-difluoro-1,3-dioxolane-2-one. The content of 4,5-difluoro-1,3-dioxolane-2-one is preferably within a range from 5 wt % to 50 wt %, or in the case where 4,5-difluoro-1,3-dioxolane-2-one is mixed and used with 4-fluoro-1,3-dioxolane-2-one, the content of 4,5-difluoro-1,3-dioxolane-2-one is preferably within a range from 5 vol ppm to 2000 vol ppm.