NONAQUEOUS ELECTROLYTE AND LITHIUM SECONDARY BATTERY COMPRISING SAME

摘要

The present invention provides a lithium secondary battery comprising: a non-aqueous electrolyte comprising lithium bis(fluorosulfonyl)imide (LiFSI) and a phosphazene-based compound additive; a positive electrode comprising a lithium-nickel-manganese-cobalt-based oxide as a positive active material; a negative electrode; and a separator. The non-aqueous electrolyte for a lithium secondary battery according to the present invention forms a strong SEI film on a negative electrode at the time of initially charging the lithium secondary battery comprising the non-aqueous electrolyte, improves the output properties of the lithium secondary battery, and further can improve output and capacity properties after high-temperature storage.