Preliminary study on zinc-air battery using zinc regeneration electrolysis with propanol oxidation as a counter electrode reaction

A zinc-air battery using zinc regeneration electrolysis with propanol oxidation as a counter electrode reaction is reported in this paper. It possesses functions of both zincate reduction and electrochemical preparation, showing the potential for increasing the electronic energy utilization. Charge/discharge tests and scanning electron microscopy (SEM) micrographs reveal that when a nickel sheet plated with the high-H-2-overpotential metal, cadmium, was used as the negative Substrate electrode, the dendritic formation and hydrogen evolution are suppressed effectively, and granular zinc deposits become larger but relatively dense with the increase of charge time, The performance of batteries is favorable even if the charge time is as long as 5 h at the Current density of 20 mA cm(-2). Better discharge performance is achieved Using a 'cavity-opening' configuration for the discharge cell rather than a 'gas-introducing' Configuration. The highest energy efficiency is up to 59.2%. That is, the energy consumed by organic electro-synthesis can be recovered by 59.2%. Cyclic voltammograms show that the sintered nickel electrode exhibits a good electro-catalysis activity for the propanol oxidation. The increase of propanol concentration conduces to ail enhancement in the organic electro-synthesis efficiency. The organic electro-synthesis current efficiency of 82% can be obtained. (C) 2008 Elsevier B.V. All rights reserved.