In-Situ Monitoring of Interfacial Contact Resistance in PEM Fuel Cells

A new in situ method for measuring the interfacial contact resistance between the bipolar plate and gas diffusion layer of an operating PEM Fuel Cell has been developed. This method involves the insertion of probe wires, supported by a printed circuit board, between the catalyst-coated membrane and cathode side gas diffusion layer. Initial results suggest that the probe has no significant impact on fuel cell performance and produces real-time contact resistance measurements that are sensitive to changes in relative humidity and cell temperature, thus allowing the investigation of phenomena such as the oxidation of bipolar plate coatings during real operation.