Membrane electrode assembly terms

With the SPE configuration, electrodes are pressed against the membrane so that the thickness of the latter fixes the interelectrode gap. A membrane can be thiimer than a physical separator, thus reducing such a kind of contribution to IR. The ensemble of electrode and membrane is usually referred to as a membrane-electrode assembly (MEA). This term is used irrespective of the operation of the cell, that is, for both electrolyzers and fuel cells. 

Apart of this traditional meaning, recently the term of membrane electrode (assembly) is used. It is defined as two electrodes (the anode and the cathode) with a very thin layer of catalyst, bonded to either side of an ion-exchange membrane. It is an element of polymeric membrane fuel cell. 

Long-Term Testing of Membrane/Electrode Assemblies. 241... 

Long-term Stability of Membrane/Electrode Assemblies in PEFCs... 

Mechanical integrity is one of the most important prerequisites for fuel cell membranes in terms of handhng and fabrication of membrane electrode assemblies, and to offer a durable material. Robust fuel cell membranes are required because of the presence of mechanical and swelling stresses in the application [172]. Moreover, membranes should possess some degree of elasticity or elongation to prevent crack formation. 

Table 3.8. Long-Term Experiments for Catalysts in Fuel Cell Single Membrane Electrode Assemblies... 

It is useful to discuss the performance characteristics of an eCMR in terms of a polarization plot to help understand its various modes of operation depicted in Figure 15.4. This analysis follows our earlier approach (Choi et al., 2004 Thampan et al., 2001 Vilekar Datta, 2010), in which we consider the membrane electrode assembly (MEA) for a fuel cell cCMR as consisting of the live layers, an electrical analog of which is shown in Figure 15.5. 

Mocoteguy P, Ludwig B, Scholia J, Nedellec Y, Jones DJ, Roziere J (2010) Long-term testing in dynamic mode of HT-PEMFC H3PO4/PBI Celtec-P based membrane electrode assemblies for micro-CHP applications. Fuel Cells 10(2) 299-311... 

In the two preceding chapters (2 and 3), different aspects of state-of-the-art catalysts and membranes as well as new approaches for these two components were discussed. Starting with the central part of low temperature fuel cells, adjacent to the membrane electrode assembly (MEA) is the gas difiusion media, which ensures a uniform distribution of reactant ses and the transport of products away from the electrodes on a micro- and millimeter scale. The fuel cell is then accomplished by the flow field which is required for a uniform distribution of the reactant across the whole electrochemically active area The chapter starts with a discussion of gas diftiision media and their impact on performance. Different flow field stmctures and requirements for stable and long-term operation of fuel cells are presented. The chapter concludes with an introduction to system-level aspects and overall considerations of system efficiency including other components such as humidifiers and cooling strategies. 

Hamon, C., Purdy, G., Kim, Y.S., Pivovar, B. and Zelenay, P. (2006) Novel process for improved long-term stability of DMFC membrane-electrode assemblies. Proceedings - Electrochemical Society, vol. P2004-21, pp. 352-362. 

Wood, D., Davey, J., Garzon, E, Atanassov, P. and Borup, R. (2004a) Effects of long-term PEMFC operation on gas diffusion layer and membrane electrode assembly physical properties. Presented at the 206th Meeting of The Electrochemical Society, Honolulu, HI, Abstract No. 1881, October 3-8,2004. 

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