A Combination Model for Macroscopic Transport in Polymer-Electrolyte Membranes
The membrane is the heart of the fuel-cell sandwich and hence the entire fuel cell. It is this electrolyte that makes polymer-electrolyte fuel cells (PEFCs) unique and, correspondingly, the electrolyte must have very specific properties. Thus, it needs to conduct protons but not electrons as well as inhibit gas transport in the separator but allow it in the catalyst layers. Furthermore, the membrane is one of the most important items in dealing with water management. It is for these reasons as well as for others that modeling and experiments of the membrane have been pursued more than any other layer .
Although there have been various membranes used, none is more researched or seen as the standard than the Nafion®family by E. I. du Pont de Nemours and Company. Like the other membranes used, the general structure of Nafion is a copolymer between polytetrafluoroethylene and polysulfonyl fluoride vinyl ether. These perfluorinated sulfonic acid (PFSA) ionomers exhibit...
KeywordsLiquid Water Transport Mode Expanded Channel Permeation Coefficient Ionic Domain
We would first like to thank the funding sources for this work, UTC Fuel Cells, LLC, EPA through a STAR graduate fellowship (91601301-0) and the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Hydrogen, Fuel Cell, and Infrastructure Technologies, of the U.S. Department of Energy under contract number DE-AC02-05CH11231. We would also like to thank Stephen Paddison and Keith Promislow for inviting us to write this chapter.
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