POSITIVE ELECTRODE ACTIVE MATERIAL AND METHOD FOR MANUFACTURING A POSITIVE ELECTRODE ACTIVE MATERIAL

A positive electrode active material for lithium-ion rechargeable batteries comprises particles having Li, M′, and oxygen, wherein M′ comprises Ni, in a content x, wherein x≥80 at %; Co in a content y, wherein 0.01≤y≤20.0 at %; Y in a content b, wherein 0.01≤b≤2.0 at %; and Zr in a content c, wherein 0.01≤c≤2.0 at %, all at % being relative to M′, and optionally Mn and D. D is at least one element selected from B, Ba, Ca, Cr, Fe, Mg, Mo, Nb, S, Si, Sr, Ti, V, W, and Zn. The material comprises monolithic particles, wherein the particles have a Co content Coas measured by cross-sectional EDS at an edge of the particles, and a Co content Coas measured by cross-sectional EDS at a center of the particle, wherein the ratio Co/Co>1.10.