HYDRAZINE FUEL CELL BATTERY

1,267,883. Hydrazine fuel cells. VARTA A.G. 30 June, 1970 [3 July, 1969], No. 31592/70. Heading H1B. In a hydrazine fuel cell in which the electrodes are porous and hydrazine is present in the circulating alkaline electrolyte, each hydrazine electrode comprises a self-supporting structure of powdered nickel, iron or cobalt or an alloy thereof amalgamated with at least 0À3% of mercury. The nickel powder may be sintered carbonyl nickel. The oxidant electrode may be silver-plated or of Raney silver. It may be amalgamated, at least on the electrolyte side. In one embodiment, the nickel hydrazine electrode is soaked in sodium borohydride solution to load it with hydrogen and then amalgamated in mercuric nitrate solution. The oxidant electrode, which has porous surface layers of carbonyl nickel on both faces and is additionally silver-plated on the gas side, is also soaked in sodium borohydride, but amalgamated with mercuric chloride solution containing some hydrochloric acid. The electrolyte is aqueous potassium hydroxide. In an alternative embodiment (Fig. 3), the hydrazine electrode comprises porous layers 1 separated by spacer 8 through which electrolyte containing hydrazine is fed; the oxygen electrode comprises coarse pored layer 2 through which oxygen is passed from conduit 6 and fine pore surface layers 3. Hydrazine-free electrolyte flows through duct 5, and 7 represents a protective diaphragm. The electrolyte is aqueous potassium hydroxide.