The practical use of lithium metal anodes in solid-state batteries requires a polymer membrane with high lithium-ion conductivity, thermal/electrochemical stability, and mechanical strength. The primary challenge is to effectively decouple the ionic conductivity and mechanical strength of the polymer electrolytes. We report a remarkably facile single step synthetic strategy based on in-situ crosslinking of poly(ethylene oxide) (xPEO) in the presence of a woven glass fiber (GF). Such a simple method yields composite polymer electrolytes (CPE) of anomalously high elastic modulus up to 2.5 GPa over a broad temperature range (20 °C – 245 °C) that has never been previously documented. An unsupervised machine learning algorithm, K-mean clustering analysis, was implemented on the hyperspectral Raman mapping at the xPEO/GF interface. Using such a unique means, we show for the first time that the promoted mechanical strength originates from xPEO and GF interactions through dynamic hydrogen and ionic bonding. High ionic conductivity is achieved by the addition plasticizer (e.g. tetraglyme), where trifluoromethanesulfonate anions are tethered to the xPEO matrix and Li⁺ cations are favorably transported through coordination with the plasticizer. Further, stringent galvanostatic cycling tests indicates the CPE can be stably cycled for >3000 h in a Li-metal symmetric cell at a moderate temperature (nearly 1500 Coulombs/cm² Li equivalents), outperforming most of the PEO-based electrolytes. The GF reinforced CPE reported here has multifunctional uses, such as solid electrolytes for all solid-state batteries and membranes for redox-flow batteries. Although the focus of this study is on lithium-based batteries, the results are equally promising for other alkali metal based batteries such as sodium and potassium.

锂金属阳极在固态电池中的实际使用需要具有高锂离子传导性，热/电化学稳定性和机械强度的聚合物膜。主要的挑战是有效地使聚合物电解质的离子电导率和机械强度脱钩。我们报告了一种在编织玻璃纤维（GF）存在下基于聚环氧乙烷（xPEO）原位交联的非常简便的单步合成策略。这种简单的方法可以在以前从未记载的宽温度范围（20°C – 245°C）内产生高达2.5 GPa的异常高弹性模量的复合聚合物电解质（CPE）。在xPEO / GF接口的高光谱拉曼映射上实现了一种无监督的机器学习算法，即K均值聚类分析。使用这种独特的方法，我们首次证明了提高的机械强度源自通过动态氢和离子键的xPEO和GF相互作用。通过添加增塑剂（例如四甘醇二甲醚）可实现高离子电导率，其中三氟甲磺酸根阴离子束缚在xPEO基质和Li⁺阳离子通过与增塑剂协调良好地输送。此外，严格的恒电流循环测试表明，CPE可以在中等温度（接近1500 Coulombs / cm ² Li当量）的锂金属对称电池中稳定循环> 3000 h ，胜过大多数基于PEO的电解质。此处报道的GF增强CPE具有多种用途，例如用于所有固态电池的固体电解质和用于氧化还原液流电池的膜。尽管此研究的重点是锂基电池，但对于其他基于碱金属的电池（如钠和钾），结果同样具有希望。