| abstract |
A nickel composite hydroxide having a reduced content of sulfate radicals and chlorine as impurities is obtained. The method includes a crystallization step of crystallization in a reaction solution obtained by adding an alkaline solution to an aqueous solution containing nickel and cobalt, an aqueous solution containing an ammonium ion supplier, and an aluminum source. The solution is a mixed aqueous solution of alkali metal hydroxide and carbonate, and the ratio [CO32 −] / [OH−] of the carbonate to the alkali metal hydroxide in the mixed aqueous solution is 0.002 or more and 0.050 or less. In this way, Ni1-xy CoxAly (OH) 2 + α (0.05 ≦ x ≦ 0.35, 0.01 ≦ y ≦ 0.2, x + y <0.4, 0 ≦ α ≦ 0.5) Are spherical secondary particles formed by agglomerating a plurality of plate-like primary particles, and the secondary particles have an average particle size of 3 to 20 μm and a sulfate radical content of 1.0% by mass or less. And the chlorine content is 0.5 mass% or less , Carbonates content obtained nickel composite hydroxide is 1.0 mass% to 2.5 mass%. [Selection figure] None |