Interface compatible organic-inorganic solid electrolyte with intimate electrode/electrolyte interfacial contact for dendrite-free Li metal batteries

The increasing demand for safe, high-energy-density batteries drives the development of solid-state electrolytes. Organic/inorganic hybrid electrolytes, integrating the benefits of polymer and inorganic electrolytes, exhibit flexibility, high mechanical strength, and superior ionic conductivity. However, interfacial incompatibility between organic/inorganic components and high electrolyte/electrode interfacial resistance restricts their practical applications. Herein, a flexible and high ionic conductive organic/inorganic electrolyte is prepared via the simple electrospinning of Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 @polyacrylonitrile (LAGP@PAN) and then in-situ polymerization of vinylene carbonate (VC). The LAGP fillers are homogenously distributed in PAN fibers, contributing to the compatible interface between the polymer matrix and inorganic reinforcement. The in-situ polymerization of VC to poly(vinylene carbonate) (PVCA) further improves the intimate electrolyte/electrode contact. As a result, the LAGP@PAN/PVCA electrolyte exhibits a high ionic conductivity of 2.05 × 10 −4  S cm −1 at 30 °C. The Li|LAGP@PAN/PVCA|Li symmetric cell can stably cycle for over 2300 h. The Li|LAGP@PAN/PVCA|LiFePO 4 cell exhibits excellent cycling performance with a capacity retention of 88 % after 700 cycles at 1C. Even combined with commercial LiFePO 4 cathode and thin Li foil anode (N/ P  = 2), the full cell also shows stable cycling performance. This study presents a promising approach to mitigate interfacial challenges in solid electrolytes, facilitating the development of Li metal with high-safety and high-energy density.