Preparation And Electrochemical Properties Of Zine Electrodes For Zinc/Nickel Secondary Batteries

The research and development of chemical power sources, zinc-based and nickel-zinc batteries was reviewed. The shape change, dendrite formation, corrosion and passivation of the rechargeable zinc electrode and the ways to solve the above problems were discussed as well. Then, the preparation and electrochemical behavior of pasted zinc electrode and its application in the Zn/Ni battery were studied systematically in this paper.By means of the electrochemical measurement, the effect of the metal oxide additives such as PbO, Bi2O3, In2O3 and electrolytic additive of :C16H33(CH3)3NBr. on the performance of zinc electrode were investigated. The result shows that the addition of PbO, Bi2O3, In2O3 in zinc electrode can improve the morphology of zinc deposition and prevent it from dendrite growth and deformation. And also, the dendrite growth of zinc was inhibited by the addition of C16(CH3)3NBr in the electrolytes through the absorption in active sites on the surface of zinc electrode which will suppress zinc deposition.The addition of calcium hydroxide in zinc electrode can reduce the solubility of zinc oxide and improve discharge capacity, cycling life and utilization of active material. The low solubility of calcium zincate produced from the chemical reaction of zinc oxide and calcium hydroxide in alkaline solution can improve the cycling life the zinc electrode, and the discharge capacity will tend to be stable. Furthermore, the effects of La2O3 additives on the electrochemical performances of zinc electrodes were investigated. The results shows that the addition of La2O3, in zinc electrode can improve the area of reduction peak and the hydrogen evolution potential which means the cathodic hydrogen evolution reaction can be hindered. For the other hand, La2O3 additives can improve the activation process and discharge capacity obviously for zinc electrode. The appropriate content of La2O3 additives in zinc electrode can increase the electrochemical properties of the zinc electrode.Zn/Ni battery with the zinc electrode containing calcium additive showed better discharge capacity and charge-discharge cycling life. Zn/Ni battery with three layers of separators had longer cycling life than one layer of separator.