POSITIVE ELECTRODE ACTIVE SUBSTANCE FOR HIGH-PERFORMANCE LITHIUM ION BATTERY AND METHOD FOR PRODUCING POSITIVE ELECTRODE ACTIVE SUBSTANCE

Provided are a lithium nickel metal complex oxide powder having low alkalinity and excellent cycle characteristics, a lithium ion battery positive electrode active material containing the same, a lithium ion battery positive electrode using the active material, and a lithium ion battery having the positive electrode. A lithium nickel metal complex oxide exhibiting excellent cycle characteristics and low alkalinity is successfully produced by controlling the crystal grain size and composition ratio in a lithium nickel metal complex oxide powder.