| 摘要 |
331,080. Johnson, J. Y., (I. G. Farbenindustrie Akt.-Ges.). June 14, 1929). Electrodes.-Active material for accumulators is produced by subjecting metal powders, such as nickel or iron, mixed with at least 5 per cent of additional substances capable of removal, to a sintering process with or without the aid of pressure. The additional substances are removed simultaneously or subsequently by solution, volatilization &c. The metal powders may be produced from the corresponding carbonyls. The substances to be removed to make the plate porous may consist of sodium or potassium chloride or sulphate, ferric aluminium or mercuric chloride, ammonium bicarbonate or chloride or oxalate, oxalic acid, urea-, naphthalene &c. Pressure over the mass during sintering may be produced by carrying out the process in an atmosphere of ammonia which also delays the volatilization of the additional substances and ensures satisfactory sintering. Carbon may also be used as an additional material and may be removed from a slab of sintered nickel by oxidaion in air, steam or carbon dioxide. Any nickel oxide which may be formed may be reduced ,electrolytically or in a stream of hydrogen. Substances such as iron oxide and mercury oxide which are not intended to be removed may be added to the original metal powder mixture. Nickel plates obtained by this process may be impregnated with a solution of nickel nitrate and used as anodes in accumulators having an alkaline electrolyte. |
