Metal‐Organic Frameworks for Electrolytes and Interfaces in Rechargeable Batteries: from Liquid to Solid‐State Systems

The development of next‐generation rechargeable batteries necessitates multi‐faceted electrolyte architectures that can satisfy a wide range of demanding requirements, including high ionic conductivity, electrochemical and thermal stability, structural (or mechanical) integrity, selective ion transport, and interfacial compatibility. Metal‐organic frameworks (MOFs) have emerged as a uniquely versatile platform to address these challenges, owing to their diverse chemical functionalities, tunable porous architectures, and host‐guest interactions with electrolyte species. These features enable MOFs to serve multiple roles across battery components — from facilitating selective ion transport and stabilizing electrode interfaces to suppressing parasitic side reactions. While prior studies have explored MOFs in isolated applications, this review provides a comprehensive and integrative perspective on their use across the full spectrum of electrolyte systems, ranging from liquid to solid‐state. The evolution of MOFs is detailed from early ionic conductors to functional separators, interlayers, hybrid electrolytes, and solid‐state conductors. Emphasis is placed on design strategies that harness MOF chemistry to regulate ion selectivity, transference number, interfacial reactivity, and mechanical stability. Finally, Key challenges and emerging directions are outlined to realize the potential of MOFs in enabling high‐performance, all‐solid‐state battery systems. This unified overview offers a distinct framework for guiding MOF‐based electrolyte design in next‐generation energy storage technologies.