A comprehensive and practical framework for advanced battery management system of vanadium redox flow batteries

The practical and effective design of the battery management system (BMS) is crucial to achieving high performance, long service life, and safe operation of all battery types, including vanadium redox flow batteries (VRFBs). However, without having a comprehensive and practical battery management scheme design as the foundation to develop an industrial or commercial-scale BMS for VRFBs, various underlying factors that promote the deployment of VRFBs in many projects that incorporate renewable energy sources (RESs) for decarbonisation resulting in economic benefits cannot be accomplished. In this paper, an advanced VRFB-BMS scheme is proposed that achieves high performance in state of charge (SOC) estimation, hydraulic control and thermal management without requiring excessive computational resources. Rigorous validations of this proposed VRFB-BMS scheme are carried out based on a state-of-the-art zero-dimensional (0-D) model to demonstrate the performance of the proposed BMS scheme design including case studies that showed: (1) a 8.1% increase in round-trip efficiency; (2) automatic capacity rebalancing and highly accurate half-system SOC estimation method with a mean absolute percentage error (MAPE) less than 1% when the system is severely imbalanced; and (3) the ability to conduct effective thermal management with the use of a heating, ventilation and air-conditioning system (HVAC). The studies also demonstrated the capability of integrating the BMS with the energy management system (EMS) to achieve specified objectives for the users. This can bring numerous economic and environmental benefits to satisfy the objectives of the decision-makers or the investors.