Abstract: A method of preparing a double layered nickel hydroxide comprising the steps of spraying a first solution of nickel sulfate solution and aqueous ammonia into a first reaction bath, reacting the first solution with sodium hydroxide for a predetermined time to form a core of nickel hydroxide, injecting the core of nickel hydroxide into a second reaction bath, spraying a second solution of nickel sulfate and aqueous ammonia into the second reaction bath, reacting the second solution and sodium hydroxide with the core of nickel hydroxide and growing the core of nickel hydroxide to form an outer layer on the core of nickel hydroxide, the outer layer having a different physical property from the core, is provided.

Abstract: A powder is provided which may be used for alkali rechargeable batteries and a method for producing it. The powder includes boron containing nickel hydroxide particles having a generally spherical shape. The boron is present in an amount in the range of from 0.5 to 5.0 mol % B.

Abstract: A method for preparing nickel hydroxide is provided, in which a nickel sulfate solution and ammonium hydroxide are continuously mixed in a premixing vessel to form a nickel ammonium complex, and then the mixed solution and a sodium hydroxide solution are continuously supplied to a reactor. Included in the method of producing nickel hydroxide is the step of adding more than one element selected from the group consisting of Co, Zn and Cd to the nickel sulfate solution in a concentration range of 0.05-0.3 mol/L. The high density nickel hydroxide may be used for alkali rechargeable batteries.