Research Of Cylindrical Zinc-Air Battery

Among all batteries, because of steady performance, source of raw material and low-cost, the study and the development of zinc-air battery is paid more and more attention. Because of high specific energy and inexpensive and environmentally benign materials, zinc-air batteries are promising energy storage devices.Research of cylindrical zinc-air battery in this thesis includes: study on the catalyst of air electrode, study on the zinc electrode, design and assembly of cylindrical zinc-air battery.In order to improve the electrocatalytic activity of MnO₂, catalysts were prepared from the carbon powder impregnated with Mn(NO₃)₂ and rare-earth nitrate(La(NO₃)₃-6H₂O) and alkaline-earth nitrate(Sr(NO₃)₂), and heated at 270°C. The air electrode was obtained by cold-pressing. Electrochemical performance of the electrodes was studied by current-potential polarization curves and AC impedance test. The current-potential polarization result showed that air electrode exhibited the best performance when stoichiometric ratio of various element of catalyst was Mn:La:Sr=1:0.4:0.6, its polarization is the smallest, at the current density 2¹50mA/cm² the air electrode potential can be improved by 32 226mV. The analysis of AC impedance spectra showed that added rare-earth oxide and alkaline-earth oxide to the system can decrease the charge-transfer resistance and oxygen diffusion resistance. Another experiment was made to find the performance of AA size zinc-air battery using this type catalyst. The discharge results showed that rare-earth oxide and alkaline-earth oxide can significantly enhance the zinc-air battery's capacity and operating voltage.The experiment researched effect of the structure of zinc electrode on zinc-air battery. The result showed that the zinc-air battery composed of eight segments zinc electrode had better discharge performance.