发表机构
The Ohio State University（俄亥俄州立大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过电-化学-力学耦合连续模型揭示，表面突起周围的应力变化是锂全固态电池中不均匀沉积的关键，并探讨了人工中间层调控界面电流分布的潜力。
AI 中文摘要
全固态电池（ASSBs）有望实现高能量密度和增强的安全性，但其发展受到固-固界面不稳定性和不相容性的阻碍。在锂金属全固态电池中，尽管陶瓷电解质刚度高，锂穿透仍会沿晶界发生，通常由轻微的锂/固态电解质界面不规则性引发。本文提出一个具有电-化学-力学耦合的二维连续介质模型，以研究在堆叠压力和施加电流密度下，具有表面粗糙化硫银锗矿电解质的锂全固态电池中的界面电流分布。我们的理论分析和模拟研究强调了机械应力在界面电流分布中的关键作用。我们发现，细长表面突起周围的显著应力变化是锂沉积不均匀的关键，若无这种应力变化，即使在粗糙表面上锂沉积也会变得均匀。此外，我们的参数化研究表明，在低界面电流密度与交换电流密度之比下，应力效应主导过电位和电流分布；否则，表面粗糙度引起的界面面积增大所导致的高界面电阻将占主导地位。基于这些见解，我们还讨论了通过工程化人工中间层来调节界面电流分布的潜力，为改善全固态电池的长期性能和可靠性提供指导。
英文摘要
All-solid-state batteries (ASSBs) promise high energy density and enhanced safety, but their development is hindered by instability and incompatibility at solid-solid interfaces. In Li-metal ASSBs, lithium penetration occurs despite stiff ceramic electrolytes via grain boundaries, often initiated by minor Li/SE interfacial irregularities. Here we introduce a two-dimensional continuum model with electro-chemo-mechanical coupling to investigate interfacial current distribution in Li ASSBs with surface-roughened argyrodite electrolyte under stack pressures and applied current density. Our theoretical analysis and simulation studies highlight the critical role of mechanical stress in interfacial current distribution. We find that prominent stress variations around elongated surface protrusions are the key to nonuniform Li deposition, without which Li deposition becomes uniform even on a rough surface. Moreover, our parametric study elucidates that stress effects dominate the overpotential and current distribution under low interfacial current density to exchange current density ratios, otherwise the high interfacial resistance due to surface-roughness-induced interfacial area becomes dominant. With these insights, we also discuss the potential of engineering artificial interlayers to modulate interfacial current distributions, offering guidance for improving the long-term performance and reliability of ASSBs.
