A high performance redox-flow battery for grid-scale energy storage

Abstract

Batteries offer an efficient and stable solution for storing energy in the form of electricity. Among them, redox-flow batteries (RFBs) are particularly suitable for large-scale energy storage. However, even the most advanced vanadium redox-flow battery faces challenges: low voltage, high costs, and limited membrane lifespan. Herein, we present a titanium molten salt redox-flow battery (TMSRB), designed for grid-scale energy storage. Utilizing a low-cost molten chloride electrolyte and titanium-ions redox-active materials, TMSRB features a membrane-free architecture with a porous ceramic separator, delivering a higher voltage exceeding 1.55 V, ultra-fast charge-discharge performance up to 5C, a high round-trip coulombic efficiency (>97%), and an extended cycle life. This work lays the foundation for a new battery principle, which could lead to the production of economical energy-storage devices for grid-scale energy storage and enabling broader deployment of renewable energy technologies.