Cross-Linked Chains of Metal–Organic Framework Afford Continuous Ion Transport in Solid Batteries

Metal–organic frameworks (MOFs) have attracted intensive study as solid electrolytes (SEs) in recent years. However, MOF particles work separately in SEs and numerous interfaces hinder a high-efficiency ion transport, which lowers the performance of solid-state batteries (SSBs). Herein, continuous ion-conductive paths were constructed by cross-linked MOF chains. Chains of a newly developed MOF (Zr-BPDC-2SO3H) were grown on bacterial cellulose (BC) nanofibers to provide a continuous ion transport network. The cross-linked MOF chains exhibit a high ionic conductivity of 7.88 × 10–4 S cm–1 at 25 °C, single-ion transport ability (tLi+=0.88), a wide electrochemical window up to 5.10 V, excellent interface compatibility, and the capability for suppressing lithium dendrites. Most importantly, the SSB fabricated with the cross-linked MOF chains shows more than 100% improved specific capacity in comparison to an SSB without this design and stable cycling performance at 3 C. This work provides a splendid strategy for developing high-performance SEs with porous ion conductors.