Field-Enhanced Carbon Monoxide Tolerance of Polymer Electrolyte Membrane (PEM) Fuel Cells

To be commercially competitive, PEM fuel cells have to be able to run on readily available fuels. Fuel reformers are practical, but fuel cell anode catalysts are severely poisoned by small quantities of carbon monoxide from the reformer. Despite mucheffort invested into increasing CO tolerance, desired performance levels have not been achieved.Our Phase I data has demonstrated excellent CO-tolerance when magnetic particles are introduced into the fuel cell anode. Local magnetic fields couple into kinetic pathways through spin polarization and can alter product distributions and reaction rates.The overall objective of the Phase II research is to demonstrate that the field-enhancement is sustainable and scalable. To this end, magnetic particles with improved functionality will be fabricated and their physical and chemical properties studied.Membrane electrode assemblies will be fabricated incorporating these particles and their performance will be tested with a variety of techniques in order to gain a better understanding of the underlying mechanism and to define performance limits andfavorable operating conditions. A final validation step in an air-breathing stack suitable for military application is also proposed. The proposed Phase II effort, if successful, will lead to a breakthrough in carbon monoxide tolerance and performance of reformate-fed hydrogen/air polymer electrolyte membrane fuel cells, and therefore result in their widespread use in portable,transportation and stationary applications.