Effects of gallium on electrochemical discharge behavior of Al-Mg-Sn-In alloy anode for air cell or water-activated cell

In order to evaluate the electrochemical properties of aluminum alloy anode under high current densities in alkaline electrolyte, the galvanostatic discharge, potentiodynamic polarization and hydrogen evolution tests of three experimental Al-Mg-Sn-In-(Ga) alloys were performed. The results show that the alloying element gallium improves the working potentials of experimental Al-Mg-Sn-In alloys under different discharge current densities. The average working potentials of the alloys containing gallium can reach -1.3 V under current density ranging from 650 to 900 mA/cm2, while those of alloy without Ga are only -1.0 V. Such phenomenon is attributed to the solid solution which can form amalgam with aluminum matrix. Such an amalgam can form the hydrolyzed species during the discharge process and lead to the corrosion infiltrating into aluminum matrix.