In-Situ Reference Electrode Testing for Cathode Carbon Corrosion

Abstract

Carbon corrosion of the cathode electrode is a significant decay mechanism in PEM fuel cells that must be mitigated in order to meet start/stop cycle requirements. A measurement technique which uses an in-situ reference electrode was developed to measure the interfacial potentials which cause carbon corrosion. Start/stop cycles are studied using this diagnostic tool in real time where both inlet and outlet interfacial potentials are measured. Rate of carbon loss per cycle is estimated using the measured interfacial potentials. An improved shutdown method was studied using the reference electrode and was demonstrated to be effective. Throughout the testing the reference electrode measurements verified the predicted interfacial potential trends, and proved to be reliable.