Electrochimica Acta, Vol.228, 91-99, 2017
Carbon-free Solid Dispersion LiCoO2 Redox Couple Characterization and Electrochemical Evaluation for All Solid Dispersion Redox Flow Batteries
Semi-solid flow batteries have been reported to have among the highest energy densities for redox flow batteries, however, they rely on percolated carbon networks which increase the electrolyte viscosity significantly. We report the first demonstration of carbon-free redox flow couples comprised of dispersed lithium-ion battery active material suspensions, with sub-micrometer LiCoo(2) (LCO) particles at the cathode and Li4Ti5O12 (LTO) particles at the anode. Both electrochemical and rheological properties of the LCO suspensions are reported and compared to previous reports for LTO dispersed electrochemical redox couples. An LTO anode and LCO cathode full cell was constructed and reversible electrochemical redox reaction of the dispersed particles was successfully demonstrated. This carbon-free dispersed lithium ion active material full cell provides a proof-of-concept for a system that lies between the relatively high viscosity semi-solid flow cells with percolated carbon networks and the relatively low energy density conventional flow cells comprised of dissolved transition metals, providing a system for future study of the trade-off between energy density and viscosity for electrochemical flow cells that rely on solid active materials. (C) 2017 Elsevier Ltd. All rights reserved.