IJTP HomeIssue Contents

Two Dimensional Phenomena in Intermediate Temperature PEMFCs
Denver F. Cheddie and Norman D.H. Munroe

Proton exchange membrane fuel cells (PEMFCs) operating with Nafion® membranes have encountered numerous problems associated with water management and CO poisoning because of their low temperature of operation. Higher temperature membranes have been investigated for use in PEMFCs, one such membrane being polybenzimidazole (PBI). Mathematical modeling, which is essential to the development of fuel cell technology, has been limited to PEMFCs using Nafion® membranes. This paper presents two-dimensional models, which predict the temperature and concentration profiles in an intermediate temperature PEMFC using a PBI membrane. These models separately account for rib effects and variation of transport properties along the gas channels. For nominal supply gas flow rates, concentration variations arise due to the presence of ribs; whereas significant temperature variations occur along the gas channels, where the heat generated within the fuel cell is transported via convection.

full text (IP)