Through-plane thermal conductivity of 14 SIGRACET gas diffusion layers (GDLs), including series 24 & 34, as well as 25 & 35, and of micro porous layer (MPL) is accurately measured under different compression, ranging from 2 to 14 bar, at a nominal temperature of 60 degrees C. The effect of compression, PTFE loading, and of MPL on thermal conductivity and contact resistance is investigated experimentally, and measurements are presented for the first time for the contact resistance between an MPL and a GDL for an MPL-coated GDL substrate. A new and robust mechanistic model is presented for predicting the through-plane thermal conductivity of GDLs treated with PTFE and is successfully verified with the present experimental data. The model predicts the experimentally-observed reduction in thermal conductivity as a result of PTFE treatment, and provides detailed insights on the functional dependence of thermal conductivity on geometric parameters, compression, and PTFE. The model can be used in performance modeling and in design of polymer electrolyte membrane fuel cells. (C) 2013 Elsevier B.V. All rights reserved.