NICKEL COMPOSITE HYDROXIDE AND PROCESS FOR PRODUCING SAME POSITIVE ACTIVE MATERIAL FOR NONAQUEOUS-ELECTROLYTE SECONDARY BATTERY AND PROCESS FOR PRODUCING SAME AND NONAQUEOUS-ELECTROLYTE SECONDARY BATTERY

摘要

The present invention provides a positive electrode active material having a high particle-diameter uniformity with a suitable particle diameter and a nickel complex hydroxide as a precursor thereof. When the nickel complex hydroxide is obtained by the crystallization reaction, a nucleation aqueous solution containing at least a nickel-containing metal compound and an ammonium ion feeder is controlled to have a pH value of 12.0 to 14.0 at a liquid temperature of 25 ° C, The particles are grown by controlling the pH of the aqueous solution for particle growth containing the nuclei formed at a liquid temperature of 25 ° C to 10.5 to 12.0 and a pH value lower than the pH value in the nucleation step. In this case, it is preferable that at least at the time of starting the grain growth process, in a non-oxidizing atmosphere having an oxygen concentration of 1% by volume or less in a range exceeding 40% with respect to the entire time of the grain growth process, The stirring power for volume is controlled to 0.5 to 4 kW / m 3.