Measurement of heat fluxes and electrodes temperature in a proton exchange membrane fuel cell were performed using platinum wires and heat flux sensors. A temperature difference of 6 °C to 9 °C between the electrodes and the bipolar plates was observed for a cell operating at a current density of 1.5 A.cm-2. These measurements show a strong non-uniformity of the temperature profile through the membrane electrode assembly that future models should take into account. Simultaneous heat fluxes measurements have allowed to evaluate in situ the effective thermal conductivity of the porous layers. Values of the order of 0.3 W.m-1.K-1 were found.
