Preparation and characterization of polybenzimidzaole/diethylamine hydrogen sulphate for medium temperature proton exchange membrane fuel cells

The measured proton conductivity, from symmetrical H2 cell, however, is ca. 4 times lower than that of the measured ionic conductivity. This could be estimated roughly by considering proton conduction where the proton is associated with two anions A− resulting in ionic agglomerate HA2− with more than double the ionic radius of A− and consequently less than half of its diffusivity. Additionally, considering the solvation number of that agglomerate to be 1.0 will result not only in a slower proton diffusion and lower conductivity but will also cause serious flooding and mass transport limitation at the cathode. This cumulative effect will limit the life of the cell due to the IL migration from anode and membrane to the cathode.