Development of an Optical Sensor for Temperature Measurement and Water Droplet Detection in PEMFC Gas Channels

Thermal and water management in Proton Exchange Membrane (PEM) fuel cells provide a significant challenge for engineers and fuel cell designers as both have a direct effect on performance and durability. Internal temperature is very difficult to measure due to component geometry and the internal environment possessed by PEM fuel cells along with a lack of sufficient temperature measurement methods which are often highly invasive. This research presents initial developments for creating a non-intrusive temperature measurement system, based on the principles of phosphor thermometry, which also has the ability to optically detect liquid water formation and movement in PEMFC gas channels. The sensor was designed, calibrated and then installed in a 25 cm² PEM fuel cell for in-situ testing. The experimental data show that a relationship exists between temperature variation and water droplet movement in gas channels of a PEM fuel cell.