Standard Article

Catalyst coated composite membranes

Fuel Cell Technology and Applications

Polymer electrolyte membrane fuel cells and systems (PEMFC)

Membrane–electrode–assembly (MEA)

  1. S. Cleghorn,
  2. J. Kolde,
  3. W. Liu

Published Online: 15 DEC 2010

DOI: 10.1002/9780470974001.f303049

Handbook of Fuel Cells

Handbook of Fuel Cells

How to Cite

Cleghorn, S., Kolde, J. and Liu, W. 2010. Catalyst coated composite membranes. Handbook of Fuel Cells. .

Author Information

  1. W. L. Gore & Associates, Elkton, MD, USA

Publication History

  1. Published Online: 15 DEC 2010

Abstract

The introduction of expanding polytetrafluoroethylene (ePTFE) micro-reinforced composite perfluorosulfonic acid membranes by Gore (Gore-Select® membrane) provides numerous benefits for polymer electrolyte membrane fuel cells (PEMFCs). This chapter reviews some of the important physical properties of the membranes such as tear strength, dimensional stability, hydrogen permeability, and resistance as a function of RH, comparing a commercially available nonreinforced membrane and the Gore-Select® membrane.

The performance of the Primea® membrane electrode assembly (MEA) Series based on the Gore-Select® membrane is discussed and compared to thicker nonreinforced membranes. The reduced thickness of the electrolyte results in an obvious reduction in membrane resistance in the cell, but also provides increased membrane hydration uniformity as a result of the rapid water back diffusion. The combination of these factors provides improved power density, as well as the ability to operate fuel cell systems with sub-saturated reactant streams and at higher temperatures.

Fuel cell test results for a series of reinforced and nonreinforced membranes, along with ex-situ analysis, provides insight into predominant membrane failure mechanisms in PEMFCs. Thin reinforced membranes have been found to have significantly longer life than much thicker nonreinforced membranes, supporting the conclusion that mechanical properties of membranes maybe more important than their intrinsic chemical properties in dictating membrane life.

This chapter discusses the economic aspects of Gore-Select® composite membranes compared to commercially available pure-film membranes, including the combined benefits of increased performance and decreased ionomer content.

Keywords:

  • dimensional stability;
  • electrolyte resistance;
  • ePTFE (expanded polytetrafluoroethylene);
  • fuel cross-over;
  • gas permeability;
  • gas permeation;
  • Gore-Select® membranes;
  • high frequency resistance;
  • humidification;
  • hydrogen permeability;
  • ionic conductivity;
  • lifetime;
  • mechanical properties;
  • membrane hydration;
  • membrane electrode assembly (MEA);
  • membrane resistance;
  • membrane thickness;
  • Nafion® membranes;
  • PEM lifetesting;
  • PEM degradation;
  • perfluorinated ionomer membranes;
  • Primea® Series MEA;
  • polymer electrolyte fuel cells;
  • polymer electrolyte membranes;
  • proton conductivity;
  • reinforced membranes;
  • tear strength