Anode Pressurization of PEM Fuel Cells at Elevated Temperatures

PEM fuel cells operated at elevated temperatures (120 150 C) can greatly alleviate CO poisoning . However, at elevated temperature and ambient pressure, the cells must be operated at low relative humidity (RH), which significantly increases membrane and electrode resistance. To operate PEM fuel cells at elevated temperature and high RH, extra work is needed to pressurize the anode and cathode reactant gases. This will decrease the efficiency of the PEM fuel cell system. However, a hydrocarbon-fuel processor in series with a PEM fuel cell can produce reformed gases at high pressure with a high relative humidity without compression of gasses. The water in the anode compartment will transport through the membrane and into the cathode structure decreasing the cell resistance. The purpose of this work is to study the effect of anode pressurization on the cell resistance and performance for pure hydrogen and for simulated reformate.