VaMoS - Development of an online vanadium monitoring system to determine the state of charge of vanadium redox flow batteries

Motivation and scope

The research objective is to develop and establish a cost-effective and long-term stable monitoring system to determine the state of charge of vanadium redox flow batteries (VRFB) at any time during operation and also to provide information about the electrolyte crossover. The approach includes the development of monitoring methods that determine the State of Charge (SoC) of VRFBs both in the electrolytes of the negative half-cell and the positive half-cell in situ and independently of each other. For this purpose, already established methods such as potential measurement or coulomb counting as well as new methods and materials will be used and compared. Among others, the quartz crystal microbalance and microelectrodes will be investigated and further developed with regard to their suitability for SoC monitoring. The desired result is a reliable state-of-charge monitoring system that can be used to adapt the operating mode of VRFBs in such a way that the efficiency and the operational lifetime of the battery are increased and the operating costs are reduced. The implementation of the new monitoring method in a simple and cost-effective measuring cell and measuring technology should also provide an innovation boost for the still relatively young redox flow technology and could also be transferred from the commercially widespread vanadium system to systems with alternative electrolytes.

Das IGF-Vorhaben Nr. 21599N der Forschungsvereinigung DECHEMA e.V., Theodor-Heuss-Allee 25, 60486 Frankfurt am Main wurde über die AiF im Rahmen des Programms zur Förderung der industriellen Gemeinschaftsforschung (IGF) vom Bundesministerium für Wirtschaft und Klimaschutz aufgrund eines Beschlusses des Deutschen Bundestages gefördert.