Effects on the Performance of Low Temperature Proton Exchange Membrane Fuel Cell (LT-PEMFC) Using Oxygen Enrichment Air

A mathematical model for the 10 kW LT-PEMFC is developed to study the effects of operating parameters on the performance. The model verified by the experimental data can accurately describe the dynamic characteristics including flow rate, pressure, temperature and humidity of the LT-PEMFC system. The voltage and output power of fuel cell under different relative humidity and oxygen concentration, as well as the efficiency of fuel cells were discussed. The results demonstrate the performance of fuel cells is significantly improved at 21–30% oxygen concentration compared to 30–48% oxygen concentration, and the final power increases by 18.12%, 23.06% and 26.57% at 30%, 39% and 48% oxygen enriched air, respectively. Moreover, the minimum of the fuel cell efficiency increases to 50% above 30% oxygen enriched air form 41.55% measured under the H2/air condition. In addition, the increase of the relative humidity of anode and cathode has little effect on the performance of the LT-PEMFC above 30% humidity, and the voltage rise caused by fitted humidity in the anode is more obvious than that in the cathode at high current density. These results would have some contribution to develop more efficient LT-PEMFCs with the oxygen enriched air.