Performance of high temperature proton exchange membrane fuel cells under off-design conditions

PEMFCs are well suited for transportation applications by virtue of their efficiency and high power densities. Several advantages result by operating a PEMFC at elevated temperatures (above 100°C). An important factor to be considered during such operation is the effect of exposure to adverse off-design conditions on fuel cell performance. In this study, cells were built that conform to a defined baseline performance (H ₂/air; atmospheric pressure) at 120°C with reactant gases saturated at 90°C (38% exit relative humidity). The cells were then subject to harsh off-design conditions in a series of five increasingly challenging sequences, with temperatures going up to 150°C and reactant gas saturation temperature going down to 20°C (exit relative humidity going down to ∼2%). The first and final run in each sequence were carried out at baseline conditions to determine the effect of exposure to off-design conditions on baseline performance. The results are discussed in this paper.