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

摘要

The present invention relates to a positive electrode active material, a method for preparing the same, and a lithium secondary battery including the same. The positive electrode active material is prepared by the preparation method including: a step in which nanosol of a ceramic-based ion conductor is adsorbed onto a surface of a precursor by the precursor of a metal for the positive electrode active material being mixed with the nanosol of the ceramic-based ion conductor; and a step in which the positive electrode active material is prepared that includes lithium composite metal oxide particles and has a lithium composite metal oxide present on surface sides of the lithium composite metal oxide particles doped with a metallic element of the ceramic-based ion conductor by the precursor on which the nanosol of the ceramic-based ion conductor is adsorbed being subjected to mixing with a lithium raw material substance and heat treatment. According to the present invention, uniform doping of the lithium composite metal oxide that is present on the surface as a metallic element which constitutes the ceramic-based ion conductor can be performed, and thus structural stability is significantly improved. Accordingly, battery capacity and rate and cycle characteristics can be significantly improved.