LITHIUM NICKEL MANGANESE COBALT COMPOSITE OXIDE AS A POSITIVE ELECTRODE ACTIVE MATERIAL FOR RECHARGEABLE LITHIUM ION BATTERIES

A positive electrode active material powder suitable for lithium-ion batteries, comprising lithium transition metal-based oxide particles, said particles comprising a core and a surface layer, said surface layer being on top of said core, said particles comprising the elements: Li, a metal M′ and oxygen, wherein the metal M′ has a formula: M′=(Ni(NiMn)Co)A, wherein A is a dopant, 0.60≤z≤0.86, 0.05≤y≤0.20, 0.05≤x≤0.20, x+y+z+k=1, and k≤0.01, said positive electrode active material powder having a median particle size D50 ranging from 5 μm to 15 μm and a surface layer thickness ranging from 10 nm to 200 nm, said surface layer comprising: