| abstract |
Cathode active material for a lithium secondary battery and a lithium secondary battery with the same are disclosed. The cathode active material comprises a lithium metal complex oxide described by the following Formula 1: [Formula 1] Li[Li z A]O 2 A={M 1 n 1-x-y (M 1 n 0.78 Mn 0.22 ) x }M 2 n y (wherein, M 1 and M 2 are at least one distinct transition metal element, a rare earth element, and the combination thereof, -0.05≤z≤0.1, 0.8≤x+y≤1.8, 0.05≤y≤0.35, and the oxidation state of Ni is an oxidation number between 2.01 to 2.4). |