Effects of anodic gas conditions on performance and resistance of a PBI/H3PO4 proton exchange membrane fuel cell with metallic bipolar plates

- A high-temperature PEMFC and metallic bipolar plates are combined and tested.
- CO sensitivity of high-temperature PEMFC with metallic bipolar plates is shown.
- HT-PEMFC with metallic bipolar plates at simulated reformate gases is tested.

In this study, polybenzimidazole (PBI) is used as membrane material of the high-temperature membrane electrode assembly which has the features of high-performance stability and high CO tolerance. Moreover, compared to graphite bipolar plates, metallic bipolar plates have better mechanical properties and seismic capacity, as well as lighter weight. We thus use metallic bipolar plates and a PBI-based membrane electrode assembly to setup a single cell and examine its performance. The experimental results show that the cell temperature has a significant effect on the cell performance. When the temperature increases from 120 °C to 180 °C, the performance is significantly enhanced. Moreover, the CO tolerance of the fuel cell increases along with the temperature. At the same time, methane is fed in the anode stream to assess the performance of the cell under different simulated methane reformate gases. The test of various CH4/H2 mixtures reveals the residual methane in the reformate gases only decreases fuel cell performance slightly due to the dilution effect. We also examined H2/CO/N2/CH4 mixtures in this study, and these had only a small effect on the fuel cell performance at cell temperatures higher than 160 °C. As such, it is recommended that the cell temperature should be kept higher than 160 °C.