Method for making precursors of cathode active materials for lithium ion batteries

A process for making a particulate (oxy)hydroxide or oxide of TM, wherein TM represents one or more metals, and wherein TM comprises nickel or cobalt and, optionally, at least one metal selected from the group consisting of aluminum and manganese, wherein said process comprises the steps of:

• (a) combining an aqueous slurry of metallic nickel or cobalt and, optionally, at least one metal selected from the group consisting of manganese and aluminum with an oxidant selected from the group consisting of nitrate and peroxide in a reaction vessel under an atmosphere with less than 100 ppm O2, thereby obtaining an aqueous reaction medium with a pH value in a range of from 7.5 to 12 containing particles;
• (b) removing the particles from step (a) from a liquid in step (a) by a solid-liquid separation method, and drying the particles to obtain the particulate (oxy)hydroxide or oxide of TM;
• and
• (c) returning mother liquor obtained in step (b) to the reaction vessel.