| Zinc-silver battery has the advantages of stable output voltage, high specific power and energy, together with good security. Therefore, zinc silver battery is applied widely as reserve batteries in the special field of aviation, aerospace, military and so on. At present, it has been shown that the storage life of zinc-silver reserve battery could reach over ten years in the developed countries. The zinc electrode, as anode of the battery, is one of the most important factors affecting its storage life. In this paper, the elctrochemical perfomance of zinc electrode was studied by preparing active material, and foam silver which was used as a current collector. To improve its storage life, the volatile corrosion inhibitor was studied for the surface treatment of zinc electrode.The dendritic zinc powder prepared by electrodeposition was pursued. Then the preparing technology of electrolytic zinc powder was optimized. The best discharging performance of the electrolytic zinc powder has been gained when the electrolytic temperature was 10℃and current density was 175 mA/cm2 in the electrolyte consisited of 560 g/L KOH and 40 g/L ZnO. Under this condition, the tap density of the electrolytic zinc powder gained was 0.78 g/cm3, while its specific surface area was 4.76 m2/g, and the average particle size is about 24μm. In addition, when the pressing pressure is 15 Mpa, the mass of active material 0.19g, the zinc electrode has the largest specific discharging capacity. The specific discharging capacity of the zinc electrode can be up to 618 mAh/g, and the utilization rate is over 75% after holding for 30 s,.The foam silver as current collector has been prepared. The technology of chemical silver plating on the polyurethane foam was studied as a key point. The optimized constituent of the electrolyte was obtained. Solution A consists of 10 g/L AgNO3, 30 g/L KOH and suitable amount of ammonia water.Solution B consists of 20 g/L glucose, 100 mL/L concentrated ammonia and 1 mg/L thiourea. The foam silver matrix with good conductive property was formed by this method. However, the specific discharging capacity of zinc electrode, using the foam silver as current collector, is only 364 mA/g. So the foam silver is not suitable for current collector of zinc electrode.After the surface treatment of zinc electrode using volatile corrosion inhibitor, the effect of various additives' inhibition to hydrogen evolution on the zinc electrode was researched by the tafel testing method. The results indicated that volatile corrosion inhibitor had no significant inhibition effect on the hydrogen evolution, while the addition of indium oxide and mercury oxide was effective in inhibiting the hydrogen evolution of zinc electrode.Through the high temperature acceleration experiments, the effect of vapor inhibitors on the storage performance of zinc powder and silver peroxide were studied respectively. It was found that zinc powder was difficult to be oxidized at 71℃with the humidity of 5%. No matter whether the gas phase inhibitors existed or not, the oxidation rate of zinc powder was under 1% in one month. The decomposition of the silver peroxide could be inhibited for a certain degree with the volatile corrosion inhibitors such as cinnamic acid hexamethylene diamine, dicyclohexylamine capric acid, triethanolamine decanoic acid and benzotriazole. |
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