BATTERY

A secondary battery includes: a cathode and an anode that are opposed to each other with a separator in between; and an electrolytic solution. The cathode includes a cathode active material layer on a cathode current collector. The anode includes an anode active material layer on an anode current collector. A heat-resistant layer is provided at least in a region in which the cathode active material layer and the anode active material layer are opposed to each other between the cathode and the anode. The heat-resistant layer includes a material having a higher melting point or higher decomposition temperature than a melting point or decomposition temperature of the separator. The electrolytic solution includes an unsaturated cyclic ester carbonate.