Corner-Sharing PS₄-BS₄ Modes Facilitate Fast Ion Conduction in Lithium Thioborophosphate Iodide Glassy Solid Electrolytes

2025/07/10 by An, Yun
#Disordered Systems and Neural Networks (cond-mat.dis-nn) #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)

paper · doi:10.48550/arxiv.2507.08215

Abstract

Glassy solid electrolytes (GSEs), with their amorphous nature and the absence of grain boundaries, make them highly attractive for applications in all-solid-state lithium batteries (ASSLBs), a leading candidate for next-generation energy storage technologies. A recently developed lithium thioborophosphate iodide GSE, composed of 30Li₂S-25B₂S₃-45LiI-5P₂S₅ (LBPSI), has demonstrated excellent room-temperature ionic conductivity and low activation energy. Despite this exciting finding, the underlying mechanism behind this ultrafast ion transport remains ambiguous. Here, we accurately fine-tune the foundational MACE-MP-0 model and perform large-scale machine learning molecular dynamics simulations to investigate the structural and ion dynamics in LBPSI GSE. Our results reveal that B₂S₃ glass formers primarily form multi-bridged B_xS_y long-chain networks that impede Li⁺ conduction. In contrast, P₂S₅ gives rise to mono-tetrahedral PS₄^3- and di-tetrahedral P₂S₇^4- tetrahedra, which engage in distinctive corner-sharing modes with BS₄^5- tetrahedra, effectively disrupting the B_xS_y chains and enhancing Li⁺ mobility. Furthermore, the polyhedral anion rotations of PS₄^3- and BS₄^5- in the corner-sharing PS₄-BS₄ motifs may further promote fast Li⁺ conduction.

Citations

• A foundation model for atomistic materials chemistry
• Composite solid electrolytes for all-solid-state lithium batteries
• Electrical Energy Storage for the Grid: A Battery of Choices
• Effect of the damping function in dispersion corrected density functional theory
• A consistent and accurateab initioparametrization of density functional dispersion correction (DFT-D) for the 94 elements H-Pu
• PACKMOL: A package for building initial configurations for molecular dynamics simulations
• Efficient iterative schemes forab initiototal-energy calculations using a plane-wave basis set
• Projector augmented-wave method
• Fast Parallel Algorithms for Short-Range Molecular Dynamics
• Polymorphic transitions in single crystals: A new molecular dynamics method

Related

• Disorder-induced enhancement of lithium-ion transport in solid-state electrolytes
• Enhanced ionic conductivity through crystallization of glass-Li₃PS₄ by machine learning molecular dynamics simulations
• AI-Aided Mapping of the Structure-Composition-Conductivity Relationships of Glass-Ceramic Lithium Thiophosphate Electrolytes
• Mechanisms and Stability of Li Dynamics in Amorphous Li-Ti-P-S-Based Mixed Ionic-Electronic Conductors: A Machine Learning Molecular Dynamics Study
• Mechanism of charge transport in lithium thiophosphate