China is one of the most important manufacturing bases for electric vehicles around the word, as well as the main country of research and production of rechargeable batteries. Lithium-ion battery has a high charge/discharge rate, wide temperature adaptability, long cycle life, no memory effect, high power/energy density, as well as cost advantages. Instead of traditional batteries (NiCd, NiH), Lithium-ion battery is becoming the new power for non-plug-in electric vehicles. The electrochemical performances and developments of lithium-ion batteries are discussed, and influences of different cathode materials (NMC, LiFePO4 and LiMn2O4) on the charge/discharge performances of lithium-ion batteries are compared. Electrochemical performances of lithium-ion batteries under different temperatures are discussed, including discharge capability, high-power pulse discharge performance under high magnification, fast charge/discharge cycles life, high temperature stability of self-discharge, as well as safety of the battery under short-circuit conditions.