Voltage degradation of high-temperature PEM fuel cells operating at 200 C under constant load and start-stop conditions

摘要

High temperature proton exchange membrane fuel cells (HT-PEM) offer significant advantages over conventional low temperature fuel cells (LT-PEM), including improved fuel impurity tolerance and increased electrode kinetics. These advantages enable use of reformate fuels with potentially lower costs and simplified handling versus ultra-pure hydrogen fuel required for LT-PEM. Although HT-PEM fuel cell operation has been demonstrated at temperatures above 120 degrees C, relatively few studies have focused on operation at 200 degrees C or higher where fuel impurity tolerance is maximized, but at the cost of accelerated performance degradation. To help address this research gap, the present study investigated the voltage degradation of HT-PEM fuel cells operating at 200 degrees C and 0.4 A/cm(2) under continuous load conditions, and at 200 degrees C and 0.6 A/cm(2) during start-stop cycling. Results based on triplicate measurements show an average constant load degradation rate of 102 mu V/h, as compared to literature values of 10 mu V/h or less at lower temperature and current density. The start-stop experiments showed relatively high degradation rates per cycle up to 50 cycles, with decreasing average degradation rates over 80 and 100 cycles. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.