Non‐Flammable Electrolytes for Safe Lithium‐, Sodium‐, and Potassium‐Ion Batteries

ABSTRACT The widespread deployment of rechargeable lithium‐, sodium‐, and potassium‐ion batteries (PIBs) is critically constrained by safety concerns, particularly those associated with the flammability of conventional carbonate‐based electrolytes. In response, the development of non‐flammable electrolyte systems has emerged as a key strategy to mitigate thermal runaway risks and ensure the safe operation of energy storage devices. This review provided a comprehensive overview of recent advances in non‐flammable electrolytes, with a focus on their chemical design, thermal stability, electrochemical performance, and compatibility with battery components. Various classes of flame‐retardant materials were systematically examined, including organophosphorus compounds, halogenated solvents, ionic liquids, aqueous systems, and solid‐state electrolytes. Special attention was given to the molecular mechanisms underlying flame suppression and interfacial stability, as well as strategies for balancing safety with high energy density. By summarizing state‐of‐the‐art developments and identifying remaining challenges, including cost‐effectiveness, compatibility with high‐voltage electrodes, and long‐term cycling stability, this review aimed to guide the rational design of intrinsically safe, high‐performance battery systems for next‐generation energy technologies.