Abstract: A mixed metal hydroxide with brucite structure is described, which contains nickel hydroxide as its main component and at least one trivalent metal selected from the group consisting of Co, Fe, Al, Ga, In, Sc, Y and La in an amount of from about 12 to about 30 atom % relative to the sum of the metal components including Ni. The invention also relates to a rechargeable battery containing a mixed metal hydroxide according to the invention as an electrochemically active material as well as a secondary batter containing the mixed metal hydroxide. The invention also relates to a process for producing a mixed metal hydroxide having a brucite structure.

Abstract: Manganese(III)-containing nickel(II) hydroxide powders produced by coprecipitation carried out by dropping an acidified metal salt solution containing Ni.sup.+2 and Mn.sup.+3 ions into a feed of constant pH value, such that manganese(III) is incorporated into the nickel(II) hydroxide lattice, thereby preventing disproportionation into separate phases and improving performance characteristics of secondary battery electrodes manufactured therefrom.

Abstract: A positive collector electrode with an active material which comprises a double hydroxide of the general formula[M.sup.2+ (1-x)Fe.sup.3+ x(OH).sub.2 ].sup.x+ [(x/n)X.sup.n-, yH.sub.2 O].sup.x-in which the transient parameter is 0.05.ltoreq.x.ltoreq.0.4, preferably 0.2, M.sup.2+ is preferably Ni.sup.2+, and X.sup.n- is an anion species, shows a remarkable improvement in electrical behavior as compared to analogous double hydroxides in which X.sup.n- is SO.sub.4.sup.2-, NO.sub.3.sup.- or CO.sub.3.sup.2-. These electrodes, known as siderophile electrodes, exhibit resistance to iron contamination if X.sup.n- is formed at least partly by PO.sub.4.sup.3- or HPO.sub.4.sup.2-. This improvement is manifested in a constancy of the specific discharge capacity at a high level over many cycles during charge/discharge operation as compared to a Cd/Cd(OH).sub.2 electrode. The process for producing the electrode is also disclosed.

Abstract: A positive electrode for alkaline storage cells is disclosed. The active material for the positive electrode is a double hydroxide of the formula[M.sup.2+.sub.(1-x) Fe.sup.3+.sub.x (OH).sub.2 ].sup.x+ [(x/n)X.sup.n-..sub.y H.sub.2 O].sup.x-wherein x is in the range 0.05.ltoreq.x.ltoreq.0.4, M.sup.2+ is an oxidizable and reducible, and X.sup.n- is at least one anion. The double hydroxide has a pyroaurite-like double layer structure and is electrochemically resistant to iron poisoning. In a preferred embodiment, the double hydroxide comprises [Ni.sub.4 Fe(OH).sub.10 ].sup.+ [NO.sub.3.sup.-.yH.sub.2 O].sup.-. Methods for preparing positive electrodes having the double hydroxide active material are also disclosed.

Abstract: A positive electrode for alkaline storage cells is disclosed. The active material for the positive electrode is a double hydroxide of the formula[M.sup.2+.sub.(1-x) Fe.sup.3+.sub.x (OH).sub.2 ].sup.x+ [(x/n)X.sup.n-..sub.y H.sub.2 O].sup.x-wherein x is in the range 0.05.ltoreq.x.ltoreq.0.4, M.sup.2+ is an oxidizable and reducible, and X.sup.n- is at least one anion. The double hydroxide has a pyroaurite-like double layer structure and is electrochemically resistant to iron poisoning. In a preferred embodiment, the double hydroxide comprises [Ni.sub.4 Fe(OH).sub.10 ].sup.30 [NO.sub.3.sup.-.yH.sub.2 O].sup.31 . Methods for preparing positive electrodes having the double hydroxide active material are also disclosed.