Discharge behavior and electrochemical properties of Mg–Al–Sn alloy anode for seawater activated battery

Mg–Al–Sn alloy is one of the new developed anode materials for seawater activated batteries. The potentiodynamic polarization, galvanostatic discharge and electrochemical impedance spectroscopy of Mg–6%Al–1%Sn and Mg–6%Al–5%Sn (mass fraction) alloys in seawater were studied and compared with the commercial AZ31 and AP65 alloys. The results show that the Mg–6%Al–1%Sn alloy obtains the most negative discharge potential of average –1.611 V with a electric current density of 100 mA/cm2. EIS studies reveal that the Mg–Al–Sn alloy/seawater interfacial electrochemical process is determined by an activation controlled reaction. The assembled prototype batteries with Mg–6%Al–1%Sn alloy as anodes and AgCl as cathodes exhibit a satisfactory integrated discharge properties.