Verification of a state of the art all-vanadium flow battery model with the “Compact Storage” by SCHMID Energy Systems GmbH

Abstract:
This work deals with the verification of a state-of-the art multiphysics model of an all-vanadium redox flow battery (VRB). The VRB is seen as a promising technology especially for realizing medium-term storage systems. Due to the system’s complexity, modeling approaches are widely used to perform design and operational optimization. This work evaluates how the published modeling approaches fit to a commercial system by comparing simulation results with measurements. The measurements have been carried out using a prototype of the Compact Storage, a VRB-system manufactured by SCHMID Energy Solutions GmbH, Freudenstadt, Germany. Emphasis is laid on state-of-charge (SOC) modeling, modeling of concentration over-potential and modeling of the hydraulic circuit. While the model is able to predict SOC and the losses in the hydraulic circuit rather accurately, the published approaches for modeling concentration over-potential do not correspond very well with the measurements.