CORROSION RESISTANT, LIGHTWEIGHT, AND INEXPENSIVE METALLIC BIPOLAR PLATES WITH EXCELLENT MANUFACTURABILITY FOR PEM FUEL CELL POWER SYSTEMS

摘要

Corrosion resistant metal treated bipolar plates with higher rigidity and electrical conductivity than graphite were developed and tested for PEM fuel cell applications. Six replicas of single cells, three of which were made of graphite composites bipolar plates and the other three were made of the treated metallic plates. An Electrode Membrane Assembly (MEA) with 5.55 cm~2 active electrode areas, double-sided electrodes, 0.3 mg/cm~2 Pt loading and Nafion membrane 115 was fitted to each cell and operated under identical conditions. The experimental testing was conducted at room temperature 20°C. The obtained data from the three graphite cells were averaged and plotted and the other metallic cells' data were similarly treated and plotted on the same graph for comparison. Generally, the metallic treated bipolar plate provided at least 12% saving in hydrogen consumption in comparison to graphite. This is attributed to the lower bulk and surface contact resistance of the metal used in this study in relation to graphite. The results of the lifetime testing, conducted at room temperature under variable loading showed no indication of power degradation due to metal corrosion for at least 1500 hours.