Preparation and Properties of a Phenolic/Graphite Nanocomposite Bipolar Plate for Proton Exchange Membrane Fuel Cell

This study aims at developing lightweight and high performance sandwiched composite bipolar plates (BPs) for use in proton exchange membrane (PEM) fuel cells. For this purpose, some single and double-filler composites were manufactured by using phenolic resin as polymer and graphite (G), carbon fiber (CF), expanded graphite (EG), and carbon cloth as fillers. In order to characterize the composites, the morphology, electrical conductivity, flexural strength, toughness, hardness, porosity, and hydrogen permeation analyzes were performed. The results showed that the final composite containing 45 wt% G, 10 wt% CF, 5 wt% EG and carbon fiber cloth in middle of composite provides the electrical conductivity 101 S/cm, interface contact resistance 9 m Omega.cm(2) (in clamping pressure 150 N/cm(2)), thermal conductivity 9.6 W/(mK), flexural strength 74 MPa, and impact energy 50 J/m, without hydrogen permeation, that these are beyond the DOE criteria. Finally, a single PEM fuel cell was provided using the final fabricated bipolar plates and its in-situ performance was studied. A power density of 812 mW/cm(2) was achieved at 2.8 A/cm(2). The power and performance of final composite BP was compared with the commercially available BPs, metallic, graphitic BPs as well as the other composite BPs. The results demonstrated that the prepared composite exhibits an acceptable performance in comparison to other materials. (C) 2012 The Electrochemical Society. All rights reserved.