Comparison of Carbon Based Bipolar Plate Materials for Polymer Electrolyte Membrane Fuel Cells

Abstract

Two types of graphite composite based materials, BPP-01 with higher amount of polymer binder in comparison to BPP-02, are investigated and reported for their suitability as bipolar plates (BPPs) in polymer electrolyte membrane fuel cells (PEMFC). Through-plane electrical conductivity of pristine BPP-01 and BPP-02 are 10.31 and 11.38 S cm-1, respectively. The electrochemical behaviour of aged BPPs is examined by cyclic voltammetry (CV) in sulfuric acid. Chemically aged BPP-01 exhibits lower double layer capacitance than BPP-02. In order to observe cathodic and anodic corrosion behaviour of BPPs, potentiostatic polarisation experiments are also performed. BPP-02 undergoes higher corrosion rate than BPP-01 during cathodic polarisation. BPP-02 surface change can be observed even with bare eyes. Conversely, physical changes do not occur after anodic polarisation for both BPPs which were thoroughly characterised by profilometer, optical microscope and micro-computed tomography (μ-CT). The higher polymer content based graphite composite bipolar plate (BPP-01) endures the potential applied in PEMFC applications.