Electrochemical Characterization of Aluminum Alloy AlSi10Mg(Fe) for Its Potential Application as End Plate Material in Fuel Cells

End plates are important multi-functional components of the fuel cells. They provide structural support and are responsible for channeling the reactant gases, by-product water, and fuel cell coolant in and out of the fuel cell stack. Among various materials used for end plates, aluminum alloy is used due to its high strength and low density. But its corrosion resistance depends on the environment. The operating fuel cell conditions may cause the fuel cell coolant to become more acidic or basic in nature and thus can lead to corrosion of end plates. In this work, a common die-cast aluminum alloy, AlSi10Mg(Fe), is used for end plates, and its corrosion behavior in direct contact with the fuel cell coolant is analyzed. The electrochemical characterization of uncoated and anodized aluminum alloy was achieved using electrochemical impedance spectroscopy, potentiodynamic and potentiostatic polarization tests at room temperature and at the operating temperature of the fuel cell at 80 °C. It was found that for the uncoated aluminum alloy, the corrosion sensitivity is slightly increased when the temperature increases. In comparison, the anodized aluminum alloy reveals a decrease in corrosion sensitivity after 100 h of potentiostatic control, indicating an ongoing passivation of the surface due to the formation of aluminum oxides/hydroxides and aluminum alcohol corrosion products.