| 摘要 |
The present invention relates to an anode active material with whole particle concentration gradient for a lithium secondary battery, a method for preparing same, and a lithium secondary battery having same, and more specifically, to a composite anode active material, a method for manufacturing same, and a lithium secondary battery having same, the composite anode active material having excellent lifetime characteristics and charge/discharge characteristics through the stabilization of crystal structure as the concentration of a metal comprising the anode active material shows concentration gradient in the whole particle, and having thermostability even in high temperatures. |
| 主权项 |
1. A cathode active material for a lithium secondary battery with whole particle concentration gradient comprises:
a core expressed by the following formula 1; and a surface part expressed by the following formula 2,
Lia1M1xM2y1M3z1M4wO2+δ [Formula 1]Lia2M1xM2y2M3z2M4wO2+δ [Formula 2] wherein the concentration of M1 is constant from the core to the surface part; the concentration of M2 and the concentration of M3 have continuous concentration gradient from the core to the surface, M1, M2 and M3 are selected from the group consisting of Ni, Co, Mn and a combination thereof; M4 is selected from the group consisting of Fe, Na, Mg, Ca, Ti, V, Cr, Cu, Zn, Ge, Sr, Ag, Ba, Zr, Nb, Mo, Al, Ga, B and a combination thereof; 0<a1≦1.1, 0<a2≦1.1, 0≦x≦1, 0≦y1≦1, 0≦y2≦1, 0≦z1≦1, 0≦z2≦1, 0≦w≦0.1, 0.0≦δ≦0.02, 0≦x+y1+z1≦1, 0<x+y2+z2≦1, and y1≦y2, z2≦z1; the concentration of a metal making up the cathode active material for a lithium secondary battery shows continuous concentration gradient in the entire region, from the particle core to the surface part; and the center part of the particle is within the radius 0.2 μm from the middle of the active material particle. |
