| abstract |
Provided are nickel manganese composite hydroxide particles having a high surface Mn / Ni ratio and high particle size uniformity, which can improve the dispersibility of an active material in a positive electrode, and a method for producing the same. When a nickel manganese composite hydroxide is obtained by a crystallographic reaction, an aqueous solution for nucleation containing a metal compound containing nickel and a metal compound containing manganese and an ammonium ion supplier is prepared at a liquid temperature of 25 ° C. After performing nucleation by controlling the reference pH value to be 12.0 to 13.4, the aqueous solution for particle growth containing the formed nuclei has a pH value of 10 at a liquid temperature of 25 ° C. .5 to 12.0, and the nuclei are grown to a pH value lower than the pH value in the nucleation step, and the Mn / Ni ratio of the liquid part in the aqueous solution is increased from the middle of crystallization. . [Selection figure] None |