Numerical research on a novel flow field design for vanadium redox flow batteries in microgrid

Abstract

The microgrid (MG) composed of vanadium redox flow battery (VRFB), wind energy, and photovoltaic (PV) renewable energy, it is an effective energy solution. It has attracted much attention because it can effectively solve the problems of randomness, intermittentness, and uncontrollability of renewable energy. The VRFB plays a vital role, and its performance determines the power quality of the MG. This research analyses the development status of renewable energy, the structure of MG, and the problems of VRFB in MG. It is proposed to improve the overall performance of the battery to make up for the defect of low energy density. As the performance of VRFB is strongly affected by the electrolyte's flow rate, designing a novel flow field structure to increase the flow rate and improve the electrolyte uniformity is very important to improve battery performance. The research designed the traditional rectangular cross-section into a trapezoidal cross-section to increase the flow rate of the electrolyte and improve the uniformity of the electrolyte. Numerical simulation results show that the new flow field structure can significantly improve the electrolyte flow, alleviate the concentration polarization of the battery, and improve battery performance and efficiency. Therefore, it is found that a reasonable flow field structure design is helpful for the optimization and application of VRFB's performance. Highlights The development status of renewable energy, the structure and configuration of the microgrid, and the existing problems of VRFB energy storage are analyzed. Establishing a VRFB model for electrochemistry and fluid mechanics. Designing a novel flow field structure to improve the overall performance of the battery.