Oxygen Vacancy Nanowires Regulate the Continuous Transport Pathways and Customized Ionic Microenvironment of Solid-State Electrolytes for Stable Lithium Metal Batteries

Abstract

Poly(vinylidene fluoride) (PVDF)-based solid-state electrolytes face critical challenges of sluggish ion transport and interfacial instability in lithium metal batteries, exacerbated by crystalline rigidity and residual organic solvents. Herein, a composite solid-state electrolyte (M_3-xPVH) integrating oxygen-vacancy-rich nanowires into a PVDF-HFP matrix, which establishes the abundant continuous ion transport pathways and the customized ionic microenvironments, is designed. MoO_3-x nanowires (SNWs) with abundant oxygen vacancies not only promote the flexibility of polymer chains and capture Li⁺ to form continuous ion transport pathways for obtaining high ion conductivity of 7.58×10⁻⁴ S cm⁻¹, but also selectively bind dimethylformamide to customize the ionic microenvironment for accelerating Li⁺ desolvation and enhancing interfacial stability. Importantly, oxygen-vacancy-rich nanowires repel anions via charge repulsion and favor anion decomposition, thus forming an inorganic-rich SEI. Remarkably, Li metal anode achieves ultra-long cycling (>8000 h at 0.1 mA cm⁻²) and demonstrates excellent performance paired with the high-voltage cathode NCM811. This work pioneers a novel strategy for designing high-performance solid-state electrolytes by synergistically engineering material dimensionality and defect chemistry, unlocking new possibilities for next-generation lithium-metal batteries.