Development of a Metallic Bipolar Plate using Nano Material Coating for PEM Fuel cell Application

Abstract

Different Aluminum alloys; (pure Al, AA1050, AA3004, AA5251 and AA6061) have been used as substrate of the bipolar plate. Surface modification of the aluminum bipolar plates by applying dense coatings using electroless and electroplating (using power supply and chronoamperometry) techniques to prevent corrosion of the base metal has been investigated. Ni-P (1:0.67), Ni-Co-P (1:1:0.67 and 1:0.2:0.67), Ni-Mo-P (1:0.5:0.67 and 1:0.33:0.67) and Co-Mo-P (1:0.33:0.67) were deposited using the mentioned techniques. The surface morphology of bare and coated ones were examined using scanning electron microscope SEM. The surface changes after potentiostatic polarization experiments were also scanned, energy dispersive x-ray EDX was applied for determination of ratios of elements in the formed coatings. Potentiodynamic polarization technique (Tafel plot) was applied to study the general corrosion resistance parameters of bare and coated substrates. Potentiostatic polarization technique was applied to study the stability of different coatings formed on different substrates under long-time operating conditions of PEM fuel cells. The interfacial contact resistance values between bare or coated aluminum substrates and carbon paper were measured. Generally;