Thermal and transport properties of membranes for PEM and DMPEM fuel cells

CORTI, H. R.; ABUIN, G. C.; NORES PONDAL, F. J.; DÍAZ, L.

Sant Antonio, Texas

Conferencia; NHA Hydrogen Conference 2007; 2007

National Hydrogen Association, Estados Unidos

THERMAL AND TRANSPORT PROPERTIES OF MEMBRANES FOR PEM AND DMPEM FUEL CELLS H. R. Corti1,2*, G. Abuin3, F. Nores Pondal1, L. Diaz1 1-      Centro Atómico Constituyentes, Comisión Nacional de Energía Atómica; Av. General Paz 1499, B1650KNA Buenos Aires – Argentina. 2-      Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina 3-      Instituto  Nacional de Tecnología Industrial, B1650KNA Buenos Aires, Argentina. 1.                 Introduction Nafion 117 is a perfluorosulfonated ionomer having a polytetrafluoroethylene (PTFE) backbone with perfluoro-alkylethersulfonate side chains which account for its high chemical, mechanical and thermal stability. It is used mainly as electrolyte membrane in hydrogen feed proton exchange membrane (PEM) fuel cells. Direct methanol PEM fuel cells (DMPEM) feed with liquid methanol also use Nafion as electrolyte, but a number of alternative ionomeric materials are being tested to overcome the methanol crossover problem associated with the high permeability of methanol through Nafion. Thus, polybenzoimidazole (PBI) membranes having lower methanol permeation have been used in DMPEM fuel cells. The detailed characterization of Nafion and imidazole-based membranes is essential for the development of its technological applications. In this work we report thermal properties of Nafion 117 (Dupont) membranes and the transport properties of PBI (Goodfellow) and modified PBI synthesized in our laboratory, along with comparison of the water uptakes of these materials. * Corresponding author. E-mail: hrcorti@cnea.gov.ar