Characterization of different grades of aluminum anodes for aluminum/air batteries

Aluminum/air batteries have received much attention during the last decade because of their possible application in the field of electric vehicle propulsion. Although this system presents good theoretical characteristics, its major problem is the low practical coulombic efficiency of aluminum in strong alkaline media, resulting from its high corrosion rate. Using a grade of high purity aluminum helps to reduce corrosion but increases the material cost. Moreover, aluminum dissolves while discharging the battery, leading to an enrichment of the electrolyte in soluble aluminate species, which has a detrimental effect on the cell performance, so the electrolyte should be continuously treated by the means of a crystallizer coupled to the battery. In this context, the aim of the study is to find experimental conditions which could permit the use of a lower-cost grade of aluminum with respect to the cell and regenerator performances.