Abstract
Temperature distributions inside the operating PEFC at high current density were measured by thermocouples, thermal probes and temperature-sensitive paints, which were different devices and methods. Thermocouples of 0.1mm in diameter penetrated the separator and GDL and measured the temperatures on catalyst layer that corresponded to underneath of rib and channel, respectively. Polyimide-coated thermal probes of 0.02mm in diameter were inserted between GDL and catalyst layer and calibrated by temperature sensitivity of thermal resistance using four-terminal method. A very small amount of commercial temperature-sensitive paints, which were provided at 5 deg-C intervals, were coated onto the surface of GDL. Each method has different uncertainness and error due to the disturbance of sensing device.
