Figure 4. Left: Charging operation of a vanadium-based redox flow battery; right: discharging operation of a vanadium-based redox flow battery

From

Colourful Chemistry – from Hybrid Flow Batteries to a Powerful Redox Flow Battery with Impressive Colour Changes for a Phenomenological Approach

Jana Novotny, Dominik Quarthal, Marco Oetken

World Journal of Chemical Education. 2019, 7(2), 120-135 doi:10.12691/wjce-7-2-12