Vanadium ion battery (VIB) for grid-scale energy storage

Electricity is essential to contemporary society, fueling global demand for dependable energy. As supply-demand discrepancies exert growing pressure on power grids, large-scale energy storage systems are crucial for ensuring grid stability. Grid-scale batteries are essential for storing surplus energy and stabilizing power fluctuations. However, these systems must deliver long lifecycles, high efficiency, and unwavering safety standards. This study presents the vanadium ion battery (VIB), an advanced energy storage technology tailored to address contemporary energy requirements. The VIB herein developed delivers a high round-trip energy efficiency of 98.1 % at 1 C-rate (10 mA g −1 ) and maintains more than 80 % of the initial efficiency at 20 C-rate (200 mA g −1 ). It demonstrates long-term durability, maintaining stable performance for up to 12,000 cycles with minimal capacity degradation. These results establish the VIB as a robust, long-lasting, and scalable battery platform for grid-scale energy storage, capable of overcoming key limitations of existing technologies. • First real-world demonstration of aqueous vanadium ion battery (VIB). • Maintains over 99 % of initial capacity over 12,000 cycles at 20 C-rate. • Achieved 98.1 % round-trip energy efficiency at 1 C-rate. • Enables safe and reversible full discharge to 0 V without degradation. • Exhibits endothermic charging and minimal thermal rise during high-rate operation.