Study On Active Materials Of Primary Ni-Zn Battery

To satisfy new digital device, we need to design batteries with higher energy density. So the primary nickel-zinc battery comes up. The cathode active materials are chemically produced. By using XRD, SEM and electrochemical charge-discharge tests, we discussed some reaction conditions, such as oxidant amount, reaction temperature, lasting time and so on. The results showed that NiOOH obtained from NaClO and β-Ni(OH)2 is good in electrochemical performance. To obtain better product, there are some conditions to pay attention. The NaClO amount is 1:1 to β-Ni(OH)2. The temperature is 25℃and reaction lasts 8 hours. In addition, the OH-concentration is 5mol/L. In order to promote the discharging ability, we improved the conductivity of NiOOH by chemically coating CoX4+ Co1-X3+OOH1-X on the surfaces. And the spherical graphite powder coated in this way has been discharged to evaluate the stability. The chemically synthesized material shows a higher conductivity because of its high oxidation state. Consequentially, the CoX4+ Co1-X3+OOH1-X coated spherical Ni(OH)2 shows a higher utilization ratio in comparison with that of the regular CoO-doped spherical Ni(OH)2. The anode is another important component for primary nickel-zinc battery. But the zinc gel is easy to dissolve in the alkaline electrolyte. So we have to use some additive to prohibit the dissolvability. In,Bi and A1 can slow the anode dissolvability. The ideal amounts of these three elements are 1.0%, 0.05% and 0.01% respectively. Moreover, the zinc gel shows better capacity when these three elements are both added. It suggested that the elements could help each other in slowing the zinc dissolvability. By the way, In2O3,PbO and Tl2O3 have the same effect as those three elements. And by electroplating the collector and using PW—150 as the adhesive, we can get zinc gel with better electrochemical capacity.