The Optimized Interfacial Compatibility of Metal–Organic Frameworks Enables a High-Performance Quasi-Solid Metal Battery

Metal–organic frameworks (MOFs) have been attracting a great deal of attention as potential solid electrolytes (SEs). However, the interfacial compatibility of MOF-based SEs caused by the physical contact among MOF particles, the polymer binder, and electrodes is not yet fully determined. Herein, a bioinspired design strategy aiming to build ion transport pathways at interfaces was introduced. The MOF-to-MOF transport paths were built via in situ ring opening of epoxide, akin to the protein molecules that transport the ion across the cell walls. After optimization, the obtained SE is endowed with a high ion conductivity of 1.70 × 10–3 S cm–1 at 30 °C, a wide electrochemical window of 4.6 V, a high Li+ transference number of 0.8, and a decreased interface resistance. Consequently, the fabricated quasi-solid metal batteries exhibit higher and more stable cycling performance compared to the performance of those without interface optimization. This strategy for optimizing the interfacial compatibility of MOFs thus exploits a new avenue for developing high-performance SEs for various metal batteries.