Doped manganese dioxides
View Patent ↗An active manganese dioxide electrode material that exhibits improved electrochemical performances compared with conventional manganese dioxide materials includes at least one dopant. The doped manganese dioxide electrode materials may be produced by a wet chemical method (CMD) or may be prepared electrolytically (EMD) using a solution containing manganese sulfate, sulfuric acid, and a dopant, wherein the dopant is present in an amount of at least about 25 ppm.
1. A cathode of an alkaline battery, comprising a composition of electrolytic manganese dioxide and a doped manganese oxide corresponding to the formula Mn 1-x X w O y in which w is about 0.000023 to 0.0144, and y ranges from about 1.90 to 2.00, X is at least one dopant selected from the group consisting of: B, Mg, Al, Si, P, Sc, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb, Ru, Rh, Pd, Ag, In, Sn, Sb, Ba, Ce, Hf, Ta, Re, Os, Ir, Pt, Au and Bi, and in which the manganese, oxygen and the dopant are intermingled atomically, and wherein x is about 0.0046 to 0.0087.
2. The cathode of claim 1 further comprising a conductive material and wherein a combined weight of the conductive material, the electrolytic manganese dioxide and the doped manganese oxide is at least ninety weight percent of the cathode on a dry basis.
3. An alkaline battery, comprising the cathode of claim 1 and an anode comprising zinc.
4. An alkaline battery, comprising the cathode of claim 1 and an electrolyte comprising potassium hydroxide.