POSITIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM SECONDARY BATTERY, METHOD FOR PREPARING THE SAME, AND LITHIUM SECONDARY BATTERY COMPRISING THE SAME

摘要

The present invention relates to a positive electrode active material for a lithium secondary battery, a manufacturing method thereof, and a lithium secondary battery including the same. The positive electrode active material comprises: lithium cobalt oxide particles; and a surface treatment layer positioned on a surface of the lithium cobalt oxide particles. The lithium cobalt oxide particles comprise on the surface thereof lithium cobalt oxide, with lithium deficiency, having Li/Co of which the mole ratio is less than 1, belonging to a space group of Fd-3m, and having a cubic crystal structure. The surface treatment layer comprises a lithium compound comprising a transition metal and one or more elements selected from a group consisting of elements of a group 13. Therefore, a side reaction with an electrolyte solution is prevented, a high capacity as well as improved rate properties and initial capacity are shown due to high packing density, and excellent output and lifespan properties are shown due to excellent lithium conductivity.