Abstract:
In this study, the effects of hydrogen flow rate, oxygen flow rate, cell and humidification temperature on power density were examined experimentally. The experiments have been carried out on a single proton exchange membrane (PEM) fuel cell with the active area of 25 cm(2). Response surface methodology (RSM) was used to determine the optimum conditions of PEM fuel cell by Design-Expert 8.0 (trial version). It was found that temperature had an important effect on the performance of PEM fuel cell by the results of experiments. Increasing both cell and humidification temperature increased the performance of the fuel cell system. Even cell performance decreases after exceeding a definite temperature. An increase occurred in performance at low cell potential with increasing the hydrogen flow rates. And, maximum power density, whose value was 0.5495 mW/m(2), was reached at these conditions of 0.4 V, 5 L/min hydrogen flow rate, 70 degrees C humidification temperatures and 40 degrees C cell temperatures.