Figures index

From

Vanadium Redox Flow Batteries with Different Electrodes and Membranes

A. Habekost

World Journal of Chemical Education. 2018, 6(1), 8-13 doi:10.12691/wjce-6-1-2
  • Figure 1. Schematic of a redox flow battery. The redox couple solutions are circulated through the redox cell containing the electrodes and the proton exchange membrane
  • Figure 2. Components of a VRFB cell stack
  • Figure 3. Carbon felt
  • Figure 4. CV of vanadium (III) (left) and vanadium (IV) on graphite (right). The absence of the anodic (Figure 4, left) and cathodic current peak (Figure 4, right) indicates that the reduction V(III) → V(II) and the oxidation V(IV) → V(V) are irreversible on graphite. Scan rate 50 mV/s
  • Figure 5. CV of vanadium (IV) on gold (Au-BT). The small cathodic current peak indicates that the oxidation V(IV) → V(V) is irreversible. Note that the cathodic peak at 0.5 V results from the sulphuric acid
  • Figure 6. Carbon nanotubes, decorated with nano gold (SEM kindly from DropSens)
  • Figure 7. CV vanadium (IV) at different treated carbon nanotubes. The anodic peaks around 0 V result from C=O and C-O moieties on the CNT-electrode
  • Figure 8. Solid line: ECL of [Ru(bpy)3]2+ alone (100μmol/L) , dotted line [Ru(bpy)3]2+ with 30 μmol/L V(IV)
  • Figure 9. Absorbance at 390 nm as a function of the voltage (SPE: Au-At)
  • Figure 10. Absorbance of the oxidation product of V4+ at different wavelengths as a function of the applied voltage. Insert: Absorption spectra derived from the absorbance vs voltage curves
  • Figure 11. Experimental setup VRFB. From left to right: Pumps, reservoirs for the vanadium solutions, cell (between the pumps), power supply for charging, motor and data logging
  • Figure 12. One part of the used cell with two hoses, the metal pick-up electrode and the carbon felt electrode. All compounds are mounted in a Plexiglas chamber. The alligator clip is connected with the data logging system
  • Figure 13. Charging and discharging of a VRFB. A. Charging, B: open-circuit, C: with a motor as load
  • Figure 14. Simple setup that shows the color change of the anode region after charging and discharging