Measuring temperature inside PEMFCs is necessary for proper water management, because water vapor pressure is a strong function of temperature. In this paper, we have developed thin film thermocouple (TFTC) array to measure temperature distributions near the Cathode Catalyst layer (CCL) with a resolution smaller than the rib-channel scale.
The sensor array was placed between CL and gas diffusion layer (GDL) at the cathode. No performance decrement was observed with the insertion of TFTC array. The measurements of temperature distributions showed that the temperature rises at the cathode CL is about 9 °C at 1.2 A/cm2 with supplying 98.5 % RH Hydrogen / Air.