AI 中文总结
本研究采用分子动力学模拟揭示玻璃态Li-S-P-B-I电解质中B-S与P-S网络的相互作用，发现适量P₂S₅可通过解聚硼框架提升离子电导率并实现脆-韧转变，过量则阻碍Li⁺迁移，为相关玻璃电解质设计提供原子层面原理。
AI 中文摘要
由硫化物和卤化物玻璃构成的电解质因具有可加工性、无晶界及较高的离子电导率，成为全固态锂电池的有前景候选材料。然而，它们的离子电导率和力学性能仍无法满足实际应用需求。固体电解质的重大进展需要对其微观结构有透彻理解。本研究通过基于机器学习原子间势的分子动力学模拟，揭示了一系列玻璃态固体电解质中结构、离子传输性能与力学稳定性之间的关联。具体而言，探究了玻璃态Li-S-P-B-I（LSPBI）中B-S网络与P-S网络的相互作用如何调控离子电导率和变形行为。向基于B₂S₃的玻璃中引入P₂S₅会引发关键的结构转变，在此过程中离子电导率和力学纳米延展性均可得到提升。对于中等含量的P₂S₅，引入的PS₄单元会解聚刚性硼框架，为快速离子传输创造渗流扩散路径；同时，柔性P-S-P构型可通过键弯曲实现能量耗散，引发脆-韧转变。但过量的P₂S₅会增加多磷酸盐（如P₂S₆和P₂S₇）的占比，进而使结构网络聚合，最终阻碍Li⁺迁移。本研究为设计兼具离子电导率和力学稳健性的玻璃电解质提供了原子层面的原理。
英文摘要
Electrolytes composed of sulfide and halide glasses are promising candidates for all-solid-state lithium batteries owing to their processability, lack of grain boundaries, and relatively high ionic conductivity. Nevertheless, their ionic conductivity and mechanical properties are still not satisfying for the real-world applications. Significant advances in solid electrolytes require a thorough understanding of their microstructures. Here, we reveal the connections among structure, ionic transport properties, and mechanical stability in a series of glassy solid electrolytes by employing molecular dynamics simulations based on a machine learning interatomic potential. Specifically, we explore how the interplay between B-S and P-S networks in glassy Li-S-P-B-I (LSPBI) governs ionic conductivity and deformation behavior. The introduction of P2S5 into a B2S3-based glass induces a critical structural transformation, through which both ionic conductivity and mechanical nano-ductility can be enhanced. For a moderate P2S5 content, incorporated PS4 units depolymerize the rigid boron framework, creating percolative diffusion pathways for fast ionic transport. Concurrently, the flexible P-S-P configurations enable energy dissipation through bond bending, leading to the brittle-to-ductile transition. However, excessive P2S5 increases the fraction of polyphosphates (e.g., P2S6 and P2S7), thereby polymerizing the structural network and ultimately impeding Li+ mobility. Our work thus provides atomistic principles for engineering glass electrolytes with balanced ionic conductivity and mechanical robustness.
