METHOD FOR PREPARING CATHODE ACTIVE MATERIAL FOR LITHIUM SECONDARY BATTERY, AND CATHODE ACTIVE MATERIAL PREPARED BY PREPARATION METHOD

The present invention relates to: a method of preparing a positive electrode active material including forming a first coating layer on a surface of a lithium transition metal oxide represented by Formula 1 by using a basic aqueous solution containing a coating element M (where M includes at least one selected from sodium (Na) and aluminum (Al)), and forming a second coating layer by dry-mixing the lithium transition metal oxide, on which the first coating layer formed, and a raw material containing a coating element M (where M includes boron (B)) and performing heat treatment on the mixture; a positive electrode active material prepared by the preparation method; a positive electrode for a lithium secondary battery including the positive electrode active material; and a lithium secondary battery.