Patent ID: 7709154

Claim:
A lithium secondary battery comprising: a positive electrode including lithium-nickel-based or a lithium-nickel-manganese-based oxide; a negative electrode including a lithium metal, a lithium-containing alloy, a material that is capable of reversible intercalation/deintercalation of lithium ions or a material that is capable of reversibly forming a lithium-containing compound; and a non-aqueous electrolyte comprising: a lithium salt, an organic solvent comprising a mixed solvent of a carbonate solvent and an aromatic hydrocarbon solvent, a first additive compound selected from the group consisting of compounds represented by formula (1) and derivatives thereof: where R 1 is selected from the group consisting of alkyls, ester radicals, and aliphatic carbonate radicals, and the first additive compound is present in an amount from 0.01 to 5 wt % based on the total amount of the electrolyte, and a second additive compound selected from the group consisting of compounds represented by formula (3), wherein X is selected from the group consisting of halogen radicals, cyano radicals, and nitro radicals, and the second additive is present in an amount from 0.01 to 5 wt % based on the total amount of the electrolyte.