Transition metal composite hydroxide particles and production method thereof, cathode active material for non-aqueous electrolyte rechargeable battery and production method thereof, and nonaqueous electrolyte rechargeable battery

Abstract

Provided is a cathode active material that can simultaneously improve the capacity characteristics, output characteristics, and cycling characteristics of a rechargeable battery when used as cathode material for a non-aqueous electrolyte rechargeable battery. After performing nucleation by controlling an aqueous solution for nucleation that includes a metal compound that includes at least a transition metal and an ammonium ion donor so that the pH value becomes 12.0 to 14.0 (nucleation process), nuclei are caused to grow by controlling aqueous solution for particle growth that includes the nuclei so that the pH value is less than in the nucleation process and is 10.5 to 12.0 (particle growth process). When doing this, the reaction atmosphere in the nucleation process and at the beginning of the particle growth process is a non-oxidizing atmosphere, and in the particle growth process, atmosphere control by which the reaction atmosphere is switched from this non-oxidizing atmosphere to an oxidizing atmosphere, and is then switched again to a non-oxidizing atmosphere is performed at least one time. Cathode active material is obtained with the composite hydroxide particles that are obtained by this kind of crystallization reaction as a precursor.