Unlocking Li‐Ions from “Cages” and “Shackles” in PVDF‐HFP Solid‐State Electrolyte through Synergistic Pinning Effect and Competitive Coordination

Abstract Poly(vinylidene fluoride) (PVDF)‐based solid‐state electrolytes with residual solvent are promising candidates for solid‐state batteries. However, their practical application remains hindered by restricted Li + migration and poor interfacial compatibility due to the spherulite morphology of PVDF and the strong coordination environment surrounding Li + . Herein, a synergistic strategy is proposed leveraging pinning effects and competitive coordination to disrupt Li + “cages” and “shackles” in the PVDF‐based electrolyte (PHWN). Specifically, WO 3 nanosheets achieve spherulite refinement via the pinning effect while interacting with both lithium salts and PVDF. Concurrently, N‐methylacetamide (N‐MA), acting as a competitive coordination regulator for Li + , weakens the coordination of Li + ‐solvent and modulates the rearrangement of Li + solvation. This strategy liberates Li + from confining “cages” and “shackles”, achieving an impressive ionic conductivity of 0.96 mS cm −1 . The altered interaction environment further promotes the formation of anion‐derived interphases on both electrode sides, thereby optimizing the electrode‐electrolyte interfaces. As a result, the PHWN enables ultrastable plating/stripping with minimal overpotential (50 mV) in Li||Li symmetric cells and sustains stable cycling in LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622)||Li cells with 85% capacity retention after 300 cycles at 1C. This study provides an effective strategy for targeted modulation of polymer spherulites and Li + solvation environment to improve electrolyte performance.