Bimodal lithium transition metal based oxide powder for use in a rechargeable battery

摘要

A bimodal lithium transition metal oxide based powder for a rechargeable battery, comprising: a first lithium transition metal oxide based powder, either comprising a material having a layered crystal structure consisting of the elements Li, a metal M and oxygen, wherein the Li content is stoichiometrically controlled, wherein the metal M has the formula M=Co_1−aM′_a, with 0≤a≤0.05, and wherein M′ is either one or more metals of the group consisting of Al, Ga and B; or comprising a core material and a surface layer, the core having a layered crystal structure consisting of the elements Li, a metal M and oxygen, wherein the Li content is stoichiometrically controlled, wherein the metal M has the formula M=Co_1−aM′_a, with 0≤a≤0.05, wherein M′ is either one or more metals of the group consisting of Al, Ga and B; and the surface layer consisting of a mixture of the elements of the core material and inorganic N-based oxides, wherein N is either one or more metals of the group consisting of Mg, Ti, Fe, Cu, Ca, Ba, Y, Sn, Sb, Na, Zn, Zr, Si, Nb, Mo, Ru, Rh, Pd, Ag, Cd, Sc, Ce, Pr, Nd, Gd, Dy, and Er; the first powder having an average particle size (D50) of at least 15 μm; and a second lithium transition metal oxide based powder having the formula Li_1+bN′_1−bO₂, wherein 0.10≤b≤0.25, and N′═Ni_xMn_yCo_zA_d, wherein 0.10≤x≤0.60, 0.30≤y≤0.80, 0.05≤z≤0.20 and 0≤d≤0.10, A being a dopant, the second powder having an average particle size (D50) of less than 5 μm, and preferably less than 2 μm.