Determining the Mechanisms of Cationic Contamination Affecting PEMFCs Using a Strip Cell Configuration

Cationic contanmination of polymer electrolyte fuel cells has been shown to cause serious performance degradation but the exact mechanisms of this degradation are not fully understood. A strip cell configuration was devised to study the mechanisms of performance degradation due to cationic contamination by changing the time and length scales of traditional fuel cells while providing a suitable reference electrode. This "strip cell" configuration utilizes traditional Nafion (R) membranes in an in-plane configuration with electrodes painted on each end. Using this cell it was determined that cationic contaminants collect near the cathode of the fuel cell under load and that this profile leads to increased losses primarily in the cathode region. These results can be directly related to performance losses in a typical PEMFC contaminated by foreign cations.