Secondary battery

In order to solve the problem that the existing manganese-based positive electrode material battery has insufficient high-temperature cycle and high-temperature storage performances due to the dissolution of manganese ions, the present application provides a secondary battery, comprising a positive electrode, a negative electrode and a non-aqueous electrolyte, the positive electrode comprises a positive electrode material layer containing a positive electrode active material, the positive electrode active material comprises a manganese-based material, and the non-aqueous electrolyte comprises a solvent, an electrolyte salt and an additive, and the additive comprises a compound represented by structural formula 1: