Method of producing transition metal composite hydroxide capable of serving as precursor of positive electrode active material for nonaqueous electrolyte secondary batteries and method for producing positive electrode active material for nanaqueous electrolye secondary batteries

A method for producing a transition metal composite hydroxide, the transition metal composite hydroxide being represented by a general formula (1) MxWsAt(OH)2+α(wherein, x+s+t=1, 0 <s≤0.05, 0 <s+t≤0.15, 0 ≤α≤0.5, M is at least one transition metal selected from Ni, Co and Mn, and A is at least one additive element selected from transition metal elements other than M and W, group 2 elements, and group 13 elements), being coated with a compound containing the additive element, and serving as a precursor of a positive electrode active material for nonaqueous electrolyte secondary batteries,

• the method comprising:
• a composite hydroxide particle production step including a nucleation stage and a particle growth stage,
• the nucleation stage being such that a solution for nucleation containing a metal compound having an atomic ratio of transition metals corresponding to an atomic ratio of M in the transition metal composite hydroxide, and an ammonium ion supply source is controlled to have a pH of 12.0 to 14.0 at a reference solution temperature of 25 degrees C., whereby nuclei are formed,
• the particle growth stage being such that a solution for particle growth containing nuclei formed at the nucleation stage is controlled to have a pH of 10.5 to 12.0 at a reference solution temperature of 25 degrees C. so as to have a pH lower than the pH at the nucleation stage, whereby the nuclei are grown;
• and
• a coating step wherein composite hydroxide particles obtained in the particle production step are mixed with a solution containing at least a tungsten compound to make a slurry, and the slurry is controlled to have a pH of 7 to 9 at a reference solution temperature of 25 degrees C., whereby a coating material containing a metal oxide of tungsten and the additive element or a metal hydroxide of tungsten and the additive element is formed on surfaces of said composite hydroxide particles.