LITHIUM SECONDARY BATTERY

Disclosed is a lithium secondary battery. The lithium secondary battery includes a cathode, an anode, a separator and a non-aqueous electrolyte solution. The separator includes a porous substrate, and a coating layer coated on at least one surface of the porous substrate and including a mixture of inorganic particles and a binder polymer. The non-aqueous electrolyte solution contains an ionizable lithium salt, an organic solvent, and a dinitrile compound having a specific structure. The lithium secondary battery is very safe without side reactions of the electrolyte solution. Therefore, the lithium secondary battery exhibits excellent cycle life and output performance characteristics.