A critical review on operating parameter monitoring/estimation, battery management and control system for redox flow batteries

Redox flow battery (RFB) is an efficient electrochemical energy storage technology, which has the advantages of high system stability, high electrolyte safety, long service life, etc., and has been widely used in the field of energy storage in the world. Compared with the well-reviewed research status on materials (electrodes, electrolyte, membranes and bipolar plates) and numerical simulations on RFB, the parameter monitoring/estimation, battery management and control system are insufficiently summarized and envisaged. Based on this, in this paper, the published literature on control modeling, parameter monitoring and estimation, battery management and control system for RFBs are reviewed. The importance of the control system is proposed, and the control system for RFBs is divided into three levels: for single cell, for battery stack and for battery system, according to the order from small to large, from simple to complex. Firstly, the control modeling and parameter estimation methods of single cell are summarized. In addition, it introduces the control modeling, parameter estimation and management control strategy of the battery stack, including water management system and thermal management system. Then, the control modeling, parameter estimation and control strategy of the battery system are introduced, and the energy distribution between the battery system and the power grid is explained. Finally, the control modeling, parameter estimation, management control strategy and energy distribution of RFBs are summarized and prospected, with a special emphasis on power coordination problem and fast response problem between battery system and power grid.