Testing and evaluation of aluminum coated bipolar plates of pem fuel cells operating at 70 °C

Corrosion resistant metal treated bipolar plates with higher rigidity and electrical conductivity than graphite were developed and tested for polymer electrolyte membrane (PEM) fuel cell applications. Four replicas of single cells were fabricated; two of graphite composites bipolar plates and the other two were coated aluminum. An E-TEK Series 14-W MEA with carbon cloth GDL, Nafion 112, 1.0 mg cm−2 platinum loading (anode and cathode) and 6.45 cm2 active electrode areas, was fitted to each cell and operated under identical conditions. The obtained data from the two graphite cells were averaged and plotted and the other two aluminum cells’ data were similarly treated and plotted on the same graph for comparison. Generally, the treated metallic bipolar plate provided at least a 22% savings in hydrogen consumption in comparison to graphite. This is attributed to the lower bulk and surface contact resistance of the coated aluminum plates used in this study in relation to graphite. The results of the lifetime testing conducted at 70 °C cell temperature under cyclic loading condition showed no indication of power degradation due to metal corrosion for at least 1000 h.