论文标题
玻璃陶瓷硫代磷酸锂电解质的AI辅助映射
AI-Aided Mapping of the Structure-Composition-Conductivity Relationships of Glass-Ceramic Lithium Thiophosphate Electrolytes
论文作者
论文摘要
硫磷酸锂（LPS），带有成分（li $ _2 $ s）$ _ x $（p $ _2 $ _2 $ s $ _5 $）$ _ {1-x} $是固体状态电池（SSB）最有前途的前瞻性电解质材料之一机械性能和低晶界电阻。先前已经报道了几种具有不同组成和良好LI电导率的玻璃陶瓷（GC）LP，但是由于表征实验或模拟中非晶体相的挑战，组成，原子结构，稳定性和LI电导率之间的关系尚不清楚。在这里，我们通过结合第一原理和人工智能（AI）方法，整合密度功能理论，人工神经网络电位，遗传 - 相当的采样以及从头启动的分子动力学模拟来绘制LPS相图。通过无监督的结构相似性分析，玻璃/陶瓷相位与已知LPS晶体结构中的局部结构基序相关，表明最有利的LI环境与组成有所不同。根据LPS相图的发现趋势，我们提出了一个候选固态电解质组成，（Li $ _ {2} $ s）$ _ {x} $（p $ _ {2} $ s $ s $ _ {5} $ _ {5} $ _ {1-x} $（1- x} $（$ x \ sim {$ x \ sim） （$> 10^{ - 2} $ s cm $^{ - 1} $）在我们的模拟中，从而为无定形或玻璃/陶瓷固体电解质提供了具有增强电导率和稳定性的无定形或玻璃/陶瓷固体电解质的一般设计策略。
Lithium thiophosphates (LPS) with the composition (Li$_2$S)$_x$(P$_2$S$_5$)$_{1-x}$ are among the most promising prospective electrolyte materials for solid-state batteries (SSBs), owing to their superionic conductivity at room temperature ($>10^{-3}$ S cm$^{-1}$), soft mechanical properties, and low grain boundary resistance. Several glass-ceramic (gc) LPS with different compositions and good Li conductivity have been previously reported, but the relationship between composition, atomic structure, stability, and Li conductivity remains unclear due to the challenges in characterizing non-crystalline phases in experiments or simulations. Here, we mapped the LPS phase diagram by combining first principles and artificial intelligence (AI) methods, integrating density functional theory, artificial neural network potentials, genetic-algorithm sampling, and ab initio molecular dynamics simulations. By means of an unsupervised structure-similarity analysis, the glassy/ceramic phases were correlated with the local structural motifs in the known LPS crystal structures, showing that the energetically most favorable Li environment varies with the composition. Based on the discovered trends in the LPS phase diagram, we propose a candidate solid-state electrolyte composition, (Li$_{2}$S)$_{x}$(P$_{2}$S$_{5}$)$_{1-x}$ ($x\sim{}0.725$), that exhibits high ionic conductivity ($>10^{-2}$ S cm$^{-1}$) in our simulations, thereby demonstrating a general design strategy for amorphous or glassy/ceramic solid electrolytes with enhanced conductivity and stability.
