Process for the preparation of a cobalt substituted nickel hydroxide with alpha structures stable in alkaline medium and its use in an electrochemical generator

摘要

Process for the preparation of a nickel hydroxide substituted with cobalt of alpha structure and corresponding to the formula: Ni1-xCOx(OH)2-t.yH2O.(x/n + t/n)A in which A denotes at least one anion of valency n and x, y and t are such that 0.2/=x/=0.5 0y2.5 0/=t0.6 which comprises a stage of precipitation of a mixed nickel cobalt hydroxide starting with an aqueous solution of a nickel(II) salt and with an aqueous solution of a cobalt(II) salt in the presence of the anion(s) A, and a stage of oxidation of cobalt(II) to cobalt(III) in aqueous solution or in the precipitate formed. This hydroxide can be employed as a positive electrode (6) in an electrochemical generator (1). IMAGE