Fuel Impurity Effects on High Temperature PBI Based Fuel Cell Membranes

The effects of key fuel gas impurities (CO and H2S) on the performance of high temperature PBI-based fuel cells were studied. Fuel cells with high temperature PBI-based MEAs (Celtec P-1000) showed excellent tolerance to CO (up to 2 %) at typical operational temperatures (160 - 180 °C). The fuel cell performance was very sensitive to CO content at lower operational temperatures (140 - 120 °C). Fuel cell performance was immediately recovered by switching back to pure hydrogen. Fuel cells with Celtec P-1000 MEAs showed good tolerance to 0.5 ppm H2S and limited tolerance to 25 ppm H2S at temperatures from 120 oC to 180 oC. The fuel cells also showed quick and almost full recovery when the anode gas was switched from 0.5 or 25 ppm H2S containing reformate back to pure hydrogen.