Fig. 3: Operando imaging of the active species transport in the NEUTRA beamline with the low attenuating KPF6 supporting salt.
From: Quantifying concentration distributions in redox flow batteries with neutron radiography
a Schematic representation of the non-aqueous cell designs during charge and discharge mode, where the counter electrode (CE) corresponds to 0.5 M TEMPO/TEMPO+PF6− at 50% state-of-charge in 0.2 M KPF6 and the working electrode (WE) to 0.2 M TEMPO/TEMPO+PF6− at 50% state-of-charge in 0.2 M KPF6. b Electrochemical sequence over time showing the applied potential steps and measured averaged current output at an inlet flow rate of 15.1 mL min-1. c, d Cumulative active species (TEMPO/TEMPO+) concentration profiles over the electrode thickness at an inlet flow rate of 15.1 mL min-1. The averaged snapshots of the cell after image processing and the concentration profiles are shown for various applied potential steps: c OCV, −0.3 V and +0.3 V and d −0.6 V and +0.6 V.
