Abstract: The pursuit of high-energy–density fluoride-ion batteries (FIBs) has been considerably accelerated by the escalating demand for energy storage solutions outperforming existing lithium-ion technologies. As a promising alternative, FIBs leverage fluorine—the most electronegative element—to attain exceptional electrode potentials and energy densities. A comprehensive understanding of the chemistry underlying FIBs is therefore of paramount importance. To this end, this review provides an in-depth examination of the advancements in FIB development, covering cathode materials, anode materials, and electrolytes. Special emphasis is placed on summarizing the types and electrochemical properties of electrode materials. The review concludes with a forward-looking perspective, addressing practical challenges facing FIBs, the future development of electrode and electrolyte materials, advanced in situ characterization techniques, battery reaction mechanisms, and the potential of big data-enabled machine learning (ML). This manuscript seeks to deliver a detailed review of critical areas pivotal to advancing FIB technology, delineating the scope and contributions of this work to furnish theoretical guidance and insights into future trends in the field.

Key words: Fluoride-ion batteries, Electrode materials, Electrolytes, Reaction mechanisms, Energy storage