Renewable Energy, Vol.34, No.8, 1979-1985, 2009
Transient phenomenon of step switching for current or voltage in PEMFC
The transient phenomenon of fuel cell with 5 cm(2) active area is investigated in this study by current density step increase and switching voltage under different conditions. It is found that there is an undershoot when the current density step increase is at the loading of 60% RH anode cathode, 3 stoic., 70 degrees C, 15 psi for automobile applications. The voltage is almost zero under 0.2 step increase to 1.0 A/cm(2) due to the H(+) transport in membrane or H(2)/O(2) in catalyst layer is almost used up. The undershoot phenomenon is more serious under gases stoichiometries of 3.0/3.0 when H(2) is fully humidified due to low gas concentration or flooding on the electrode. This phenomenon would induce the degradation of fuel cell components. (C) 2008 Elsevier Ltd. All rights reserved.