Thermal conductivity of proton exchange membrane fuel cell components

Proton exchange membrane (PEM) fuel cell has the potential to be one of the main energy sources in the future. However, the leading issues when operating the fuel cells are the water and the thermal managements. In this thesis, numerical studies have been developed in order to investigate the sensitivity of the PEM fuel cells performance to the thermal conductivities of the main components in PEM fuel cells, which are the membrane, the gas diffusion layer (GDL) and the catalyst layer. In addition, the effect of the thermal conductivity of these components and the metallic GDL on the temperature distribution and the water saturation was considered conducive to the improvement of the heat and water management in PEM fuel cells.

On the other hand, the experimental work was completed to determine the effects of the thermal conductivity and the thermal contact resistance of the components in PEM fuel cells. The thermal conductivity of the GDL was measured in two directions, namely the in-plane and the through-plane directions taking into account the effect of the main parameters in the GDL which are the mean temperature, the compression pressure, the fibre direction, the micro porous layer (MPL) coating and polytetrafluoroethylene (PTFE) loading. Furthermore, the thermal conductivities of the membrane and the catalyst layer were measured in both directions, the in-plane and the through-plane, with considering the effect of the temperature and the Pt loading in the catalyst layer, and the effect of the water content and temperature on the membrane. This study is a comprehensive study on the thermal conductivity of PEM fuel cells and emphasized the importance of the thermal conductivity of the components in PEM fuel cells.