Abstract：
Hybrid solid electrolytes (HSEs) aim to combine the superior ionic conductivity of inorganic fillers with the scalable process of polymer electrolytes in a unique material for solid-state batteries. Pursuing the goal of optimizing the key metrics (σion ≥ 10-4 S·cm-1 at 25 °C and self-standing property), we successfully developed an HSE based on a modified poly(ethylene oxide):LiTFSI organic matrix, which binds together a high loading (75 wt %) of Li6PS5Cl particles, following a solvent-free route. A rational study of available formulation parameters has enabled us to understand the role of each component in conductivity, mixing, and mechanical cohesion. Especially, the type of activation mechanism (Arrhenius or Vogel-Fulcher-Tammann (VFT)) and its associated energy are proposed as a new metric to unravel the ionic pathway inside the HSE. We showed that a polymer-in-ceramic approach is mandatory to obtain enhanced conduction through the HSE ceramic network, as well as superior mechanical properties, revealed by the tensile test. Probing the compatibility of phases, using electrochemical impedance spectroscopy (EIS) alongside 7Li nuclear magnetic resonance (NMR), reveals the formation of an interphase, the quantity and resistivity of which grow with time and temperature. Finally, electrochemical performances are evaluated by assembling an HSE-based battery, which displays comparable stability as pure ceramic ones but still suffers from higher polarization and thus lower capacity. Altogether, we hope these findings provide valuable knowledge to develop a successful HSE, by placing the optimization of the right metrics at the core of the formulation.
摘要：
混合固体电解质（HSE）旨在将无机填料的优异离子电导率与聚合物电解质的可扩展过程结合在固态电池的独特材料中。追求优化关键指标的目标（在25°C和自立特性下σ离子≥10-4S·cm-1），我们成功开发了一种基于改性聚（环氧乙烷）的HSE：LiTFSI有机基质，将高负载（75重量％）的Li6PS5Cl颗粒结合在一起，遵循无溶剂路线。对可用配方参数的合理研究使我们能够了解每种成分在电导率中的作用，混合,和机械内聚力。尤其是,激活机制的类型（Arrhenius或Vogel-Fulcher-Tammann（VFT））及其相关能量被提出作为揭示HSE内部离子途径的新指标。我们表明，聚合物在陶瓷方法是强制性的，以获得增强的传导通过HSE陶瓷网络，以及优越的机械性能，通过拉伸试验显示。探索阶段的兼容性，使用电化学阻抗谱(EIS)和7Li核磁共振(NMR)，揭示了中间相的形成，其数量和电阻率随时间和温度而增长。最后,通过组装基于HSE的电池来评估电化学性能，它显示出与纯陶瓷相当的稳定性，但仍然遭受较高的极化和因此较低的容量。总之,我们希望这些发现为开发成功的HSE提供有价值的知识，通过将正确指标的优化放在公式的核心。
