Proton Exchange Membrane Fuel Cell Modeling

Several complex and interrelated phenomena occur during the operation of proton exchange mebrane fuel cell (PEMFC). These processes include mass and heat transfer, electrochemical reactions, and ionic and electronic transport. Real phenomena occuring in PEMFC can only be understood through a robust fundamental model based on the physical models. These physical models are derivatives of experimental observations.

A number of issues need to be resolved before fuel cells can be commercially viable. Proton exchange membranes require precise water management, which is difficult under the variable load associated with several applications (e.g. automobile driving). Deyhdration of the membrane results in lower ionic conductivity as well as the risk of de-adhesion of the membrane, whereas excessive water production (at high current densities) results in mass transport limitations on the cathode side. Sluggish electrode kinetics is also a serious problem during the course of operation. The rate of oxygen reduction at the cathode is much slower than hydrogen oxidation at the anode, and this limits the performance of the cell. Besides these, trace amounts of CO in the hydrogen feed have severe effect on platinum based catalyst typically used in PEMFCs.