Vanadium redox flow batteries: models of dynamics and measurements

This article introduces readers to vanadium redox flow batteries, their operating principles, and state-space models. Vanadium redox flow batteries (VRFBs) are a promising technology for stationary storage of electric energy, which has a number of advantages over traditional storage batteries based on lithium-ion batteries. One of the features of VRFBs is a hydraulic system with pumps that provide a continuous supply of electrolyte from the tanks where it is stored to the stacks where the electrochemical reactions take place. This entails the need to build dynamic models of such systems, which are used for monitoring and control tasks. The article presents the basic models of vanadium battery dynamics with concentrated parameters, along with models of available measurements, and analyzes their features. In addition, new models are proposed that allow a more accurate and convenient description of the change in concentrations during VRFB operation.