Flow Battery Electroanalysis: Hydrodynamic Voltammetry of Aqueous Fe(III/II) Redox Couples at Polycrystalline Pt and Au
By Sawant, Tejal V.; McKone, James R.
Published in ACS Applied Energy Materials
Abstract
The redox flow battery (RFB) is a promising technology for large-scale electrochemical energy storage, but research progress has been hampered by conflicting reports of electron-transfer rates even for well-established battery chemistries. To address this challenge, we are working to deploy established electroanalytical techniques for precise characterization of RFB reaction kinetics. We studied Fe3+/2+ redox chemistry using rotating-disk electrode voltammetry with polycrystalline Pt and Au working electrodes as a model of an Fe/Cr RFB positive electrolyte. Our measurements yielded exchange current densities of 3.7