Abstract
Bi, a group 15 element, was added to magnesium alloys and applied to seawater batteries in marine operating machinery to improve the electrochemical performance and corrosion resistance of the battery. The electrochemical properties of as-cast pure Mg, Mg−8Al, and Mg−8Al−xBi alloy anodes in 3.5% NaCl solution were researched. Electrochemical impedance spectroscopy and an immersion test in 3.5% NaCl solution show that the Mg−8%Al−0.4%Bi alloy provides better corrosion resistance than Mg and the Mg−8Al alloy. The galvanostatic discharge results show that the Mg−8%Al−0.4%Bi alloy revealed better electrochemical properties and utilization efficiency in 3.5% NaCl solution. The Mg17Al12 and BiOCl phases formed during the discharge process of the Mg−8%Al−0.4%Bi alloy play an important role in improving the electrochemical performance and utilization efficiency of the alloy.