Investigating the Effect of Water Vapor and Residual Methanol on the Anode of High Temperature PEM Fuel Cell

The objective is to understand the effect of methanol and water vapor separately on a high temperature PEM fuel cell. An investigation was performed with different anode fuel compositions and results in terms of performance and impedance analyzed. During the initial 1000 h, cell was tested with pure hydrogen under varying current densities of 0.2 A cm-2 and 0.6 A cm-2, followed by hydrogen mixed with 15 % water vapor and then with 1 % methanol. The degradation rates at two current densities 0.2 A cm-2 and 0.6 A cm-2 were analyzed and discussed. The degradation at higher current density is more severe than at lower current density. However, on switching from higher to lower current density, the effect is reversible and the performance is improved. This suggests that some degradation is reversible. The addition of water vapor in the feed improves the performance at high current densities, which suggest an improvement of total cell resistance also supported by the impedance comparison. There is no or minimal variation in performance with the introduction of 1 % methanol along with water vapor in the anode feed at 0.2 A cm-2 and 0.6A cm-2 .