| abstract |
The present invention concerns cobalt metal agglomerates consisting of peanut-shaped primary particles, a method of producing them and their use. The primary particles have a mean particle size of between 0.1 and 0.7 νm. The proposed method is characterised in that in a first step an aqueous cobalt (II) salt solution of the formula CoX2, in which X = Cl, NO and/or 1/2 SO, is converted with aqueous solutions or suspensions of alkali and/or ammonium carbonates and/or hydrocarbonates at temperatures of between 40 and 100 °C, thus forming basic cobalt carbonate. This step is followed by separation and neutral salt-free washing. The basic cobalt carbonate thus obtained is converted by the addition of alkaline lyes to Co(OH)2, oxidized with oxidizing agents to form the heterogenite CoO(OH) which is then reduced with reducing agents to form the cobalt metal agglomerates. These can be used for producing cobalt sintered articles and positive electrodes in alkaline secondary batteries. |