Lithium cobalt based composite oxide with excellent life characteristics and positive electrode active material for secondary battery containing the same

摘要

Disclosed is a lithium-cobalt based complex oxide represented by Formula 1 below including lithium, cobalt and manganese wherein the lithium-cobalt based complex oxide maintains a crystal structure of a single 03 phase at a state of charge (SOC) of 50% or more based on a theoretical amount: €ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒLi x Co 1-y-z Mn y A z O 2 €ƒ€ƒ€ƒ€ƒ€ƒ(1) wherein 0.95‰¤x‰¤1.15, 0y‰¤0.3 and 0‰¤z‰¤0.2; and A is at least one element selected the group consisting of Al, Mg, Ti, Zr, Sr, W. Nb, Mo, Ga, and Ni.