[ASME ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology collocated with the ASME 2013 Heat Transfer Summer Conference and the ASME 2013 7th International Conference on Energy Sustainability - Minneapolis, Minnesota, USA (Sunday 14 July 2013)] ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology - Effect of PTFE on Thermal Conductivity of Gas Diffusion Layers of PEM Fuel Cells