Two methods of humidifying the anode gas, namely, external and membrane hum
idification, for a polymer electrolyte membrane fuel (PEMFC) cell are expla
ined. It is found that the water of solvation of protons decreases with inc
rease in the current density and the electrode area. This is due to insuffi
cient external humidification. In a membrane-based humidification, an optim
um set of parameters, such as gas flow rate, area and type of the membrane,
must be chosen to achieve effective humidification. The present study exam
ines the dependence of water pick-up by hydrogen on the temperature, area a
nd thickness of the membrane in membrane humidification. Since the performa
nce of the fuel cell is dependent more on hydrogen humidification than on o
xygen humidification, the scope of the work is restricted to the humidifica
tion of hydrogen using Nafion (R) membrane. An examination is made on the d
ependence of water pick-up by hydrogen in membrane humidification on the te
mperature, area and thickness of the membrane. The dependence of fuel cell
performance on membrane humidification and external humidification in the a
node gas is also considered. (C) 2001 Elsevier Science B.V. All rights rese
rved.