Preparation And Study On Zinc Electrode For Air Battery

This paper aimed at problems such as dendrite, shape change, self-corrosion and passivation of zinc electrode, researched its physical performances, electrode additives and electrolytic additives, prepared zinc electrode by different methods and optimized its ingredient and content.First, it is discussed the influence of physical performance of zinc powders on zinc electrode. The method of electro deposition was used to prepare anode materials of battery. It can be found in electro deposit experimentation that along with the current density changing from low to high, grain size of zinc powders becomes smaller; along with concentration of KOH changing from low to high, the form of zinc powders grows into three-dimension from one-dimension. The active zinc powders with dendrite and high specific surface area (0.168m~2 g~-1) were prepared by controlling the technical parameters of electro deposition, namely the current density was 160mA/cm2, the alkaline electrolytic concentration was 6M that saturated with ZnO. Thin film zinc electrode was made by the method of rolling and pressing. When the battery composed of thin film zinc electrode discharged in constant current, the utilization ratio of the active zinc powders is 71.3%, and its specific capacity is as high as 588.8mAh g~-1.Calcium zincates were prepared by two methods, namely chemical co-precipitation method and ball-milling method. Although they all belong to monocline structure, but these calcium zincates form are different. This is due to different prior growth direction of crystal in the preparation process of calcium zincates. It can be concluded from CV curves that those calcium zincates had a good cyclic behavior and high discharge capacity. When adding suitable content of Ca(OH)2 into zinc electrode, it can be obtained from experiment that zincates solubility is reduced, recharging ability of zinc electrode has improved, and the adding of Ca(OH)2 won't cause significant negative effect on anodic process.CMC serves as additive that can improve wet ability of zinc electrode and form a great dealchannels for ion conduction. The channels are good for OH" transfer and can decrease the "dry" inside electrode. Bi2+, Pb2+ were prior deoxidised before zinc ion. They serve as floor that can improve conductivity. As electrolytic additive, SDBS can stop solvent from congregating on the surface of zinc electrode to decrease anode corrosion. Discharge time of battery can be prolonging by SDBS. The mechanism can be explained in this way that organic surface-active molecules film on the surface of zinc electrode. The film takes up active center of corrosion reaction and improves activation energy of anode reaction.