Effects of Chloride Contamination on PEFCs

The performance and durability of PEFCs were investigated by introducing HCl and five different chloride salts into the air stream of an operating fuel cell. Under the same operating conditions and at a constant 28.5 mM chloride (Cl - ) concentration, cell performance degradation can be ranked as HCl> AlCl 3 > FeCl 3 > CrCl 3 > NiCl 2 , MgCl 2 . Water evaporation in the flow field surface was found to be causing precipitation of chloride salts. At lower RH, water content decreased and salt deposits completely blocked some of flow channels and caused death of the fuel cell. Moreover, contaminants crossed the GDL, reached the CCM surface, and caused significant performance drop.