Composite Polymer Electrolytes With Hierarchical Confinement of Anions and Solvents for Stable Solid‐State Li Metal Batteries

ABSTRACT Solid‐state lithium‐metal batteries leveraging solid polymer electrolytes (SPEs) represent a promising technological pathway. Among these, polyvinylidene fluoride (PVDF)‐based SPEs are particularly noteworthy, yet they face a fundamental dilemma: electrode/electrolyte interfacial degradation from solvent‐dominated Li + coordination versus constrained Li + transport under solvent‐deficient conditions. To resolve this paradox, a 3D porous few‐layered MoS 2 was synthesized and employed as the filler in PVDF‐based SPEs. The fillers concurrently weaken Li + coordination with both FSI − and solvent through targeted dipole interactions, thereby enhancing Li + migration rate and inducing structural reorganization to anion‐dominated Li + solvation. The optimized PVDF‐based electrolyte demonstrates record‐breaking ionic conductivity (1.13 mS cm −1 ), Li + transference number (0.68), and exceptional compatibility with lithium metal anodes under solvent‐lean conditions. The LiNi 0.8 Co 0.1 Mn 0.1 O 2 ||Li cell demonstrates exceptional cycling stability, achieving a record‐high capacity retention of 90.5% after 1500 cycles at 2 C. Furthermore, practical applicability is confirmed through a 54 mAh pouch cell configuration. The ultra‐stable interfacial characteristics establish new performance benchmarks, demonstrating a viable pathway toward practical solid‐state batteries with minimal solvent dependence.