LITHIUM SECONDARY BATTERY COMPRISING ELECTRODE COMPOSITION FOR HIGH VOLTAGE

摘要

A high voltage lithium secondary battery is provided to improve the discharge capacity and cycle characteristics even in case of the high voltage charge process. A high voltage lithium secondary battery comprises a positive electrode which comprises a positive electrode active material, a conductive material, and a binder in a ratio of 90-98 : 1-5 : 1-5 by weight; a negative electrode which comprises a Sn_a Cu_b-graphite composite (wherein a:b is 3:8 to 8:3); and an ion conductor. The positive electrode active material is a LiCoO2 active material formed by coating it with Co3(PO4)2 so as to form a LiCoPO4 thin film on the surface; the conductive material is carbon black (super P black); and the binder is polyvinylidene fluoride.