Zinc-nickel Battery Cathode Material

The current conditions and existing problems in the research and development of zinc-nickel batteries were analyzed in this thesis. The crystal and chemical structure characteristics and electrochemical properties of Ni(OH)₂ were investigated in the use of chemical analysis methods, SEM, XRD and so on. The preparation and application of positive electrode material Ni(OH)₂ was extensively studied. The hemicontinuous chemical deposition-crystal seed growth method was adopted for the first time to prepare the positive electrode material Ni(OH)₂. The influence of deposition reaction times was studied. The Zn/ Ni emulation batteries were assembled and their electrochemical capabilities were tested as well. The Zn/Ni primary batteries were produced at last, and their dischargeable performances were detected.In this thesis, the spherical Ni(OH)₂ with high tap density, crystallinity degree and good flowability was prepared with hemicontinuous chemical deposition - crystal seed growth method. The optimal technological parameters are: pH=11.0, reaction temperature is 50℃, NH₃/Ni= 1.1, the solid material content was controlled in the range of 140¹60g/L, and the reaction time is 7 hours . In addition, the agitation strength, the concentration of the raw material, the aging time, the charging method of raw material and some other factors were also studied. The basic crystal structure of Ni(OH)₂ was found to be β-Ni(OH)₂ by using of advanced physical analysis of SEM and XRD. The particle crystal is in order, crystallinity degree is high, and the crystallite size is big. The size of particles distributes from 5 to 15 μm.The charge-discharge capabilities of the Electrodes doped with Co, Ni, Zn, MnO₂ were studied by testing a Zn/Ni simulation battery. The results show that the effects of charge-discharge rate on the utilization of active material and average potential of electrode. Doping Co, Ni, Zn can increase the utilization of active material, enhance average potential and reduce the cycle times. But the utilization of active material and averagepotential are reduced after doping MJ1O2. Cycle Voltammetry (CV) of power microelectrodes of Ni(0H)2 showed that the higher the scanning rate in the range of 10⁵0mv/s, a higher current peak value, and cycle life of Ni(0H)2 power microelectrodes is 600 times.The Ni(OH)2 was oxidized to NiOOH when K2S2O8 was used as oxidizing agent. AAA type Zn/Ni primary batteries were made by using the alkaline manganese battery production line. The open circuit voltages of the batteries are about 1.75V. The permanent resistant (3.9Q) continuous discharge time of the Zn/Ni primary batteries is about 3 times of alkaline manganese batteries.