abstract |
A lithium secondary battery comprises an anode capable of intercalating or disintercalating lithium ions, a cathode configured with a lithium-containing oxide, and a nonaqueous electrolyte solution. The lithium-containing oxide comprises a lithium nickel based oxide. The nonaqueous electrolyte solution comprises vinyl ethylene carbonate (VEC) and a mono-nitrile compound. This lithium secondary battery solves the deterioration of charge/discharge cycle characteristics caused by a lithium nickel based oxide used for a cathode, and also controls the decomposition reaction of electrolyte to solve the swelling phenomenon even though the battery is stored at a high temperature or charged/discharged in a fully-charged state, thereby improving high-temperature life characteristics. |