LITHIUM TRANSITION METAL COMPOSITE OXIDE AS A POSITIVE ELECTRODE ACTIVE MATERIAL FOR RECHARGEABLE LITHIUM SECONDARY BATTERIES

A powderous positive electrode material for lithium ion batteries, comprising crystalline lithium transition metal-based oxide particles having a general formula Li((Ni(NiMn)Co)A)O, wherein A is a dopant, −0.030≤a≤0.025, 0.10≤x≤0.40, 0.25≤z≤0.52, x+y+z=1 and k≤0.01, wherein the crystalline powder has a crystallite size less than 33 nm as determined by the Scherrer equation based on the peak of the (104) plane obtained from the X-ray diffraction pattern using a Cu K α radiation source, and wherein the molar ratio MR(Ni) of Ni versus the total transition metal content in a cross section of a particle is higher in the surface area than in the center area of the particle, as determined by EDS analysis.