Polarization‐Induced Effect Potentiated In Situ Polymerized Electrolyte for Solid‐State Lithium Metal Batteries

ABSTRACT Solid polymer electrolytes (SPEs) hold great promise for advancing next‐generation lithium (Li) metal batteries owing to their facile processability and compositional flexibility. However, their practical applications are severely hindered by the low concentration of movable Li + and poor interfacial stability. Herein, a polarization‐induced effect potentiated in situ polymerized poly(1,3‐dioxolane)‐based electrolyte is designed. The polarized BaTiO 3 nanowires greatly promote the dissociation of Li salt to produce more movable Li + by regulating the local electrostatic environment, thereby constructing high‐throughput Li + transport pathways. Crucially, this effect facilitates the weakening of the space charge layer and enhances the in situ polymerization of monomers, thereby establishing a stable electrolyte/electrode interface. The achieved electrolyte demonstrates an ionic conductivity of 1.68 mS cm −1 at 25°C and a Li + transference number of 0.766. Remarkably, the Li anode exhibits an extended cycling life of 2000 h in the Li||Li symmetric cell. The Li||LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) full cell retains 80.5% capacity after 500 cycles at 0.5C. Detailed interface analysis indicates that inorganic‐rich solid electrolyte interface and cathode electrolyte interface are formed. This work offers a reliable design strategy for advanced lithium metal batteries with high safety and high‐energy density.