Effects of reformate on performance of PBI/H3PO4 proton exchange membrane fuel cell stack.

The present study aims to examine the effect of nitrogen and carbon monoxide concentrations as well as the working temperature and the stoichiometry number on the performance of a self-made five-cell high-temperature Proton-exchange membrane fuel cell stack (PEMFC). The concentration of hydrogen in a reformed gas can be varied, and it may contain poisonous substances such as carbon monoxide. Hence, the composition of the fuel gas could affect the performance of the PEMFC. The polarization curve and the electrochemical impedance spectrogram are utilized to examine the behaviors of PEMFC. The cell temperature of 160 °C is found as an optimal working temperature in this study for high-temperature PEMFC. Measured results show that the stoichiometry of the anode gas has a minimal effect on the PEMFC performance. A high percentage of nitrogen makes hydrogen dilute and leads to poor cell performance. When carbon dioxide exceeds 3%, the pt-catalyst was covered with the CO and the cell performance significantly decreased. Finally, a raise of the PEMFC temperature boosted the catalyst energy and improved the detachment of the carbon monoxide and eventually enhanced carbon monoxide tolerance. • A five-cell high-temperature proton exchange membrane fuel cell is studied. • The effect of different mixtures of hydrogen fuel is investigated. • The influence of carbon monoxide on performance of PEMFC is examined. • The effect of working temperature on the behavior of PEMFC is studied. • The increase of temperature improves the carbon monoxide tolerate of PEMFC. [ABSTRACT FROM AUTHOR]