Membrane electrode assembly chemical degradation

The reasons for the deterioration of ceU performance can be distinguished in reversible and irreversible power loss. Inevitable irreversible performance loss is caused by carbon oxidation, platinum dissolution, and chemical attack of the membrane by radicals [7]. Reversible power loss can be caused by flooding of the cell, dehydration of the membrane electrode assembly (MEA), or change of the catalyst surface oxidation state [8]. If corrective actions are not started immediately, reversible effects lead to irreversible power loss that we define as degradation. In this chapter, we focus on the degradation of the catalyst layer due to undesired side reactions. 

Fig. 10 Comparison of single cell lifetime and rate of ion exchange capacity (lEC) loss for different radiation-grafted membranes. The rate of lEC loss is a measure for the susceptibility of a membrane towards chemical degradation. Cell temperature 80°C. Grafting monomers S Styrene, DVB Divinylbenzene (crossUnker), AMS a-methylstyrene, MAN methacrylonitrile (comonomer), MEA membrane electrode assembly...

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