Positive Electrode Active Material, Method for Preparing the Same, and Positive Electrode and Lithium Secondary Battery Comprising the Same

A positive electrode active material comprising: (1) a lithium nickel-cobalt-manganese-based composite oxide having a nickel content 90 mol. % or more among metals excluding lithium; and (2) a metal element M1 doped in the lithium nickel-cobalt-manganese-based composite oxide. The metal element M1 comprises Al and at least one of Zr or Ti. A weight of Al is 8,000 ppm or more based on a total weight of the positive electrode active material, and a total weight of the metal element M1 is 9,000 ppm to 12,000 ppm based on the total weight of the positive electrode active material. A method for preparing the positive electrode active material, and a positive electrode and a lithium secondary battery comprising the positive electrode active material are also disclosed.