Abstract
Expanded graphite was investigated as a material for flow-field plates in PEFCs (polymer electrolyte fuel cells). Because expanded graphite is flexible but has similar material properties with normal graphite, channels on flow-field plates were designed to have single channel in order to compare operational characteristics including diffusion of reactants through ribs by comparing polarization curves and electrochemical impedance spectra between PEFCs with expanded graphite and graphite flow-field plates. As a result, PEFC with the expanded graphite flow-field plates has comparable open-circuit voltage to that with the graphite flow-field plates. However, PEFC with the expanded graphite plates had higher ohmic resistance than that with the graphite plates due to higher electrical resistance of the expanded graphite than that of the graphite. It was also found from faradaic resistances that the diffusion of the reactants through GDLs (gas diffusion layers) is disturbed in the case of the expanded graphite flow-field plates because the GDL is compressed excessively due to its flexibility.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.