Study of some basic operation conditions of an Al-air battery using technical grade commercial aluminum

Abstract

Commercial Al-6061 has been used as anode electrode to construct alkaline Al-air batteries. Functional batteries with satisfactory operation record have been constructed by using air-breathing Pt-free cathode electrodes simply made by depositing carbon black on carbon cloth. The devices were functional also in the absence of oxygen either by water reduction or by using hydrogen peroxide as oxidant, thus providing a variety of operation conditions. Al-6061 corroded fast in the alkaline electrolyte producing hydrogen at rates that approached the theoretical maximum. Fast corrosion was associated with the presence of grain impurities in the alloy and the existence of extensive grain boundaries. In this respect, corrosion of pure aluminum was much slower under the same conditions and resulted into a slower rate of hydrogen production.