Patent ID: 6129902
Filing Date: 2000-10-10
Classification: H01M,Y02E

Abstract:
A process for producing positive electrode active material for alkaline storage batteries which comprises(i) preparing a first aqueous solution which is an aqueous nickel salt solution,a second aqueous solution containing one or more salts of one or more metals selected from the group consisting of Co, Zn and Cd,a third aqueous solution containing one or more salts of one or more metals selected from the group consisting of Mn, Al, V, Cr, Fe, Cu, Ge, Nb, Mo, Ag, W, Sn, Ca, Y, Ti, Sr, rare earth metals and Bi,a fourth aqueous solution which is an aqueous alkali solution containing alkali metal ions and hydroxide ions, anda fifth aqueous solution containing ammonium ions and hydroxide ions,wherein the amount of alkali metals in the fourth aqueous solution is 1.9-2.3 moles relative to 1 mole of the total amount of metal ions in the first, the second and the third aqueous solutions, and the amount of ammonium ions in the fifth aqueous solution is 2 moles or more relative to 1 mole of the total amount of metal ions in the first, the second and the third aqueous solutions; and(ii) feeding the first, second, third, fourth, and fifth solutions simultaneously into a reaction vessel controlled at constant conditions within a pH range of 11-13 and a temperature range of 30-60.degree. C., with stirring, wherein an average residence time falls within a range of 20-50 hours, to obtain continuously a complex metal oxide having a particle diameter of 2-100 .mu.m.