Positive electrode active material for lithium secondary battery, containing high-voltage lithium cobalt oxide having doping element, and method for preparing same

The present invention provides positive electrode active material particles for a secondary battery, the particles comprising: a lithium cobalt oxide; a coating layer formed on a particle surface of the lithium cobalt oxide and containing element A; and a dopant containing element B substituted in the lithium cobalt oxide, wherein elements A and B each are independently at least one selected from the group consisting of Al, Ti, Mg, Zr, Ba, Ca, Ta, Nb, and Mo, and wherein the molar ratio of element A in the coating layer : element B in the dopant is higher than 1 : 1 and equal to and lower than 10 : 1.