Processing Methods of Epoxy/Graphite-Based Compounds for PEFC Bipolar Plates Using Different Secondary Fillers

Abstract

Polymer Electrolyte Fuel Cell (PEFC) is an environmentally friendly device that generates electricity with zero emissions. A constitutive part of PEFCs is the bipolar plate (BP), which offers mechanical support and distributes its reactant gases. In relation, manufacturing electrically conductive BPs at low cost is needed to position PEFC technology on the market. This work summarizes the processing methods of Epoxy-graphite based compounds in order to get better-synthetized samples. First, the applying of an epoxy-amine matrix composed of bisphenol A diglycidyl ether (DGEBA) and aliphatic triglycidyl ether epoxy resins cured with a polyether triamine is presented. Next, two different preparations to obtain high quality expanded graphite focuses on an appropriate graphite exfoliation were evaluated. Subsequently, three processes from graphite-resin compounds synthesis are detailed and analyzed based on Energy Dispersive X-ray Spectroscopy (EDS), Scanning Electron Microscopy (SEM), electrical conductivity tests, and particle size characterization. Besides, the effect of using different secondary fillers such as Carbon Black (CB), Graphite nanoplatelets (N99), and graphene (GR) is shown, concluding that the greater electrical conductivity is obtained using graphene in low percentages (0.5%), reaching 65.39 s.cm−1. Finally, a functional method of compression and extraction to avoid damage to the specimen is proposed.