Unlocking Fast Ionic Transport in Sub‐Nano Channels of MOF‐Based Electrolytes for Next‐Generation Batteries

Abstract

AbstractIncorporating appropriate molecules into ordered porous framework materials plays a pivotal role in modulating their physicochemical properties and dynamic behaviors. Such frameworked materials are also applicable for the preparation of solid‐state electrolyte (SSE) with altered electrochemical performance. In this work, MOF (Metal‐Organic Framework)‐based frameworked electrolytes (FEs) are prepared by the introduction of conductive ion‐molecule complexes and have investigated the electrochemical behaviors. The angstrom‐level pores in the framework enable efficient interactions with the complexes and participation in ion transportation by altering the coordinating environments of Li+ ions. As a result, the activated MOF‐based SSE exhibits an impressive ionic conductivity of 4.0×10−4 S cm−1 at room temperature (RT), along with a notably reduced activation energy of 0.12 eV at 350 K. The MOF‐based FE has been applied to Li /FE /LiFePO4 batteries, which exhibit excellent long‐cycling performance with virtually no capacity loss over 1000 cycles at the current density of 2 C at RT. The novel Li+ transport mechanisms where ion‐molecules would actively participate in the interactions between the framework and Li+ ions, not only present a new strategy for enhancing the ion transport kinetics, but also deliver outstanding electrochemical performance promising for next‐generation batteries.