Patent ID: 10270089

Abstract:
A cathode active material for a lithium secondary battery is provided which comprises a first region and a second region. The first region is represented by Chemical Formula1 wherein M1, M2 and M3 are constant: Lia1M1x1M2y1M3z1O2+δ. The second region is formed around the first regions and is represented by Chemical Formula 2 Lia2M1x2M2y2M3z2M4wO2+δ. The concentrations of M1, M2 and M3 are changed from Chemical Formula 1. In both Chemical Formula 1 and 2, M1, M2 and M3 is selected from a group including Ni, Co, Mn and combinations thereof, M4 is selected from a group including Fe, Na, Mg, Ca, Ti, V, Cr, Cu, Zn, Ge, Sr, Ag, Ba, Zr, Nb, Mo, Al, Ga, B and combinations thereof, 0<a1≤1.1, 0<a2≤1.1, 0≤x1≤1, 0≤x2≤1, 0≤y1≤1, 0≤y2≤1, 0≤z1≤1, 0≤z2≤1, 0<w≤0.1, 0.0≤δ≤0.02, 0<x1+y1+z1≤1, 0<x2+y2+z2≤1.