ABSTRACT Polymer‐based solid‐state electrolytes are attractive for solid‐state lithium (Li) metal batteries owing to their flexibility, lightweight nature, and scalable manufacturability. However, their practical application remains constrained by sluggish Li + transport, severe anion migration, and unstable electrode‐electrolyte interfaces. Herein, we reported a ferroelectrically modulated composite polymer solid‐state electrolyte, constructed by integrating an electrospun fibrous framework containing ferroelectric K 0.5 Na 0.5 NbO 3 into a solid polymer electrolyte matrix. The incorporation of ferroelectric fillers effectively suppresses polymer crystallinity, promotes the transformation of a polar β‐phase of poly(vinylidene fluoride‐co‐hexafluoropropylene), and immobilizes TFSI − anions through strong surface interactions, thereby reconstructing the local solvation environment and significantly enhancing Li + transport kinetics. Meanwhile, spatially distributed ferroelectric domains regulate local electric‐field distribution and alleviate space‐charge accumulation, enabling interconnected Li + transport pathways with homogenized ionic flux and reduced interfacial polarization, which collectively suppress Li dendrite growth. The obtained solid‐state electrolytes deliver a high ionic conductivity of 6.7×10 −4 S cm −1 with a Li + transference number of 0.68 at 30°C, and corresponding solid‐state batteries demonstrate stably cycling over 300 cycles at 1.0 C. The resulting pouch cells exhibit excellent electrochemical stability and safety performance, underscoring a ferroelectric‐enabled strategy for simultaneously addressing ion‐transport and interfacial challenges in advanced polymer‐based solid‐state electrolytes.
Jia et al. (Mon,) studied this question.