Investigation of the effect of anode fuel contaminants on the performance of PEMFC

In the present work, a two-dimensional, transient, isothermal, single-phase and two-phase, multicomponent transport model is considered for the anode-side electrode of a PEMFC. The steady-state effects of introducing the CO-contaminated hydrogen on the cell performance were investigated. Then, the dynamic behavior of a PEMFC under CO-poisoning and the effects of air bleeding on the recovery of the output current density were investigated. The numerical results of model were compared and validated with experimental results. The results indicated that even using a low CO concentration, lead to significant degradation of the fuel cell current density (about 70% of the output current was lost within 30 min when the hydrogen is pre-mixed with 10 ppm of CO as the fuel). Injecting a small amount of air into the anode stream, resulted in fast recovery of the lost current density (by injecting about 5% air into the fuel, 80% of the output current was recovered within 2 min at 53 ppm CO). Higher air bleeding ratio only resulted in minor improvement of the cell performance.