| abstract |
The present invention provides a cathode active material comprising a multiple doped lithium nickel cobalt oxide represented by Formula 1, a lithium manganese oxide represented by Formula 2, and a lithium secondary battery employing the same.n n n n n Li x Ni y Co z M n O 2 n n n n n Wherein M is Fe, Ga, Ge, Al, Ti, V, Cu, Zn, Mn, Si, P, Nb, Ta, Zr, Zn, Sn, Sb, Pt, In, Ag, Au, Bi, At least two selected from the group consisting of Pd, W and Nb, x is 0.5 to 1, y is 0.65 to 0.90, z is 0.05 to 0.30, n is 0.05 to 0.225,n n n n n Li a Mn 2-b M1 b O 4 n n n n n Wherein a is 0.98 to 1.02, b is 0 to 0.2, and M1 is at least one selected from the group consisting of Co, Cr and Ti. Cathode active material according to the present invention is excellent in capacity and cycle characteristics, can be suppressed irreversible loss and overcharge not only excellent safety, but also low manufacturing cost and excellent storage and cycle characteristics at high temperatures. Therefore, when the cathode active material is employed, it is possible to make a lithium secondary battery having a high capacity and excellent cycle life. |