Pioneering next-generation vanadium redox flow batteries

The escalating demand for long-duration energy storage underscores the pivotal role of high-performance all-vanadium redox flow batteries (VRFBs). However, the bottleneck of electrolyte cost and stability impedes large-scale deployment. This keynote addresses the transformative potential of VRFBs, propelled by breakthroughs in high-purity vanadium feedstock synthesis. We present a proprietary molten salt chlorination-distillation process that achieves the direct production of 5N-grade vanadium oxytrichloride (VOCl3). This method offers exceptional purification efficiency and scalability compared to conventional metallurgical routes. Leveraging this ultra-high-purity precursor, we have engineered a novel chlorine-sulfur hybrid electrolyte system. Electrochemical evaluations demonstrate that this system exhibits comprehensive superiority, including a enhancement in ionic conductivity, a reduction in charge-discharge overpotential, and significantly improved thermal stability and cycling durability over standard sulfate-based electrolytes. The synergistic integration of high-purity materials and optimized electrolyte chemistry not only elevates the energy efficiency and operational lifespan of VRFBs but also charts a viable pathway toward reducing the levelized cost of storage. This work substantiates that material purity and molecular-level electrolyte design are central to unlocking the full potential of vanadium flow batteries for future grid-scale applications.

Dr. -Ing. Yong FAN is a Professor of Mineral Processing at Wuhan University of Science and Technology, and State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control. FAN received his Ph.D. in Environmental Studies from Tohoku University. After research stints as a JSPS fellow at Institute of Multidisciplinary Research for Advanced Materials, as a research fellow at KU Leuven, and as a Germany A.v. Humboldt Fellow at TU Freiberg. He was promoted to Full Professor in 2020 and was the Chair Scientist of National Key R&D Program. Current research in the FAN lab emphasizes the separation and purification of strategic minerals, and the use of Distillation and Electrolysis techniques to: 1) Study Molten Slag/Flux/Metal/Gas Interaction Phenomena; 2)  Evaluate Recycling Methodology of Critical Mineral Resource; 3) Assess High Efficiency Scarce Metals Extraction; 4) Determine Innovative Material Manufacturing from By-products.