Polymer electrolyte membranes component groups

Polymer electrolyte membrane (PEM) is one of the key components of a PEM fuel cell. It serves both as an electrolyte and as a separator to prevent direct physical mixing of the hydrogen from the anode and oxygen supplied to the cathode. PEM contains ionizable groups, in which protons (mobile cations) are electrostatically associated with the fixed anionic charges on the polymer. The protons... 

The first key component of a membrane fuel cell is the membrane electrolyte. Its central role lies in the separation of the two electrodes and the transport of ionic species (e.g. hydroxyl ion, OH , in an AEM), between them. In general, quaternary ammonium groups are used as anion-exchange groups in these materials. However, due to their low stability in highly alkaline media [43,44], only a few membranes have been evaluated for use as solid polymer electrolytes in alkaline fuel cells. 

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