The Impact of Cycle Profile on PEMFC Durability

This paper reports on the effect of various simplified potential-cycle profiles (square and triangle) measured at 80oC under normal fuel cell operating voltage ranges (0.95-0.60V) in subscale fuel cells. Accurate measurements of the electrochemical surface area as well as hydrogen-oxygen I-V polarization curves were employed out to measure the change in ORR specific activity (is), mass activity (im) of commercial Pt catalyst supported on high surface area carbon per unit time as well as per cycle. Based on the measured in-situ loss of surface area and cathode catalyst activity over the first 15-30k cycles, some hints of the dissolution mechanism can be inferred. In addition, control and operation of fuel cells with lowered Pt dissolution rates can be deduced.