| abstract |
The cathode active material has composite particles each having matrix particles and coating particles coating each matrix particle, the matrix particles having the following expression: Li α Ni x My Co z O 2 , where 0.95 ≤α≤1.5, 0.6≤x≤1.0, 0≤y≤0.5, 0≤z≤0.5; x+y+z=1; and M is one of Mn and Al, the coating particles have the following expressions: Li a Ni b Mn c Co d O 2 where 0.95≤a≤1.5, 0≤b≤0.35, 0≤c≤1.0, 0≤d≤1.0 and b+c+d=1. |