LITHIUM SECONDARY BATTERY

A lithium secondary battery according to the embodiments of the present disclosure comprises: a positive electrode comprising positive active material containing lithium metal oxide particles; a negative electrode facing the positive electrode; and a non-aqueous electrolyte solution comprising a non-aqueous organic solvent, lithium salt, and an additive containing a difluorophosphite-based compound, the molar ratio of lithium in the lithium metal oxide particles to the overall metal excluding the lithium in the lithium metal oxide particles is 1.05 or greater.