Alumina dry-coated cathode material precursors

Abstract

A particulate precursor compound for manufacturing an aluminum doped lithium transition metal (M)-oxide powder usable as an active positive electrode material in lithium-ion batteries includes a transition metal (M)-hydroxide or (M)-oxyhydroxide core and a non-amorphous aluminum oxide coating layer covering the core. By providing an aluminum dry-coating process where the particulate precursor core compound is mixed with alumina powder in one or more procedures, higher doping levels of aluminum compared to the known prior art may be achieved. The crystal structure of the alumina is maintained during the coating procedures and the core of each mixed transition metal precursor particle is surrounded by a coating layer containing crystalline alumina nano particles. The aluminum concentration in the particulate precursor decreases as the size of the core increases.