Composite solid polymer electrolytes (CSPEs) have long been considered as one of the most promising candidates for all-solid-state lithium batteries owing to the merits of easy fabrication and low cost. However, the inorganic fillers physically mixed into the polymer matrix have weak polymer-filler interactions and tend to agglomerate, which limits the further improvement of the ionic conductivity and Li⁺ transference number of CSPEs. In this work, we demonstrated ZnO quantum dots can be chemically incorporated into the poly(ethylene oxide) (PEO) matrix by vapor phase infiltration (VPI), a special variant of atomic layer deposition (ALD). The ZnO quantum dots have strong chemical interactions with PEO polymer chains, which suppresses the crystallization of PEO and enhances the Li⁺ conduction. Due to the strong interactions, ZnO quantum dots distribute uniformly in the PEO-based solid electrolyte matrix as well as the top surface, which leads to a significant decrease of interfacial resistance with Li metal. As a result, the NCM811|Li half-cell with the VPI-ZnO/PEO/LiTFSI CSPE exhibit high discharge capacity at 50 ℃ (164.7 mAh g⁻¹ at 0.5 C (1 C = 200 mA g⁻¹), 2.8–4.25 V). This result could potentially serve as a model for a more general approach of using VPI to introduce strong polymer-filler interaction in CSPEs for high-performance lithium metal batteries.

由于易于制造和低成本的优点，复合固体聚合物电解质（CSPEs）长期以来一直被认为是全固态锂电池最有前途的候选材料之一。然而，物理混入聚合物基体中的无机填料具有弱的聚合物-填料相互作用并倾向于团聚，这限制了CSPEs离子电导率和Li ⁺迁移数的进一步提高。在这项工作中，我们证明了 ZnO 量子点可以通过气相渗透 (VPI)（原子层沉积 (ALD) 的一种特殊变体）化学结合到聚（环氧乙烷）（PEO）基质中。ZnO 量子点与 PEO 聚合物链具有很强的化学相互作用，抑制了 PEO 的结晶并增强了 Li ⁺传导。由于强相互作用，ZnO 量子点均匀分布在 PEO 基固体电解质基质以及顶面，这导致与锂金属的界面电阻显着降低。因此，具有 VPI-ZnO/PEO/LiTFSI CSPE 的 NCM811|Li 半电池在 50 ℃ (164.7 mAh g ^-1 at 0.5 C (1 C  = 200 mA g ^-1 ), 2.8– 4.25 伏）。这一结果有可能成为使用 VPI 在高性能锂金属电池的 CSPE 中引入强聚合物-填料相互作用的更通用方法的模型。