Residence Time Distribution of Anode Impurity Pulses in a 47-Cell Commercial PEM Stack

Concerns over increasing energy consumption coupled with the diminishing supply of fossil-fuels have led to increased research and development in several forms of alternate energy, among which is the polymer electrolyte membrane (PEM) fuel cell. One of the primary obstacles that must be overcome in the development of PEMFC’s is the source of hydrogen. PEMFC’s are extremely intolerant to impurities, with thresholds of total impurity on the order of .01% [1, 2]. Tolerance level improvement is critical, especially for mobile applications, as it would decrease the mass of the fuel reformer/storage unit and the energy consumed in fuel production. Since PEMFC systems need to be run with higher levels of impurity, the need to understand how these gases behave in the system is apparent. The following work investigates the residence time distribution of inert and reversibly adsorbing impurity pulses introduced into the anode feed of a commercially available PEMFC system.