Unraveling The Li Penetration Mechanism In Polycrystalline Solid Electrolytes

ADVANCED ENERGY MATERIALS(2021)

引用 37|浏览1
暂无评分
摘要
Lithium dendrite penetration has been widely evidenced in ceramic solid electrolytes (SEs), which are expected to suppress Li dendrite formation due to their ultrahigh elastic modulus. This work aims to reveal the mechanism of Li penetration in polycrystalline SEs through electro-chemo-mechanical phase-field model, using Li7La3Zr2O12 (LLZO) as the model material. The results show the Li penetration patterns are influenced by both mechanical and electronic properties of the microstructures, i.e., grain boundaries (GBs). Li nucleates at the GB junctions on the Li/SE interface and propagates along the GB, at which the interfacial compressive stress is small due to the GB softening. Moreover, the excess trapped electrons at the GB may trigger isolated Li nucleation sites, abruptly increasing the Li penetration depth. High-throughput simulations yield a phase map of Li penetration patterns under different trapped electrons concentrations and GB/grain elastic modulus mismatch. The map can quantitatively inform whether the mechanical or electronic properties dominate Li penetration morphologies, providing a strategy for the design of improved SE materials.
更多
查看译文
关键词
lithium dendrite penetration, lithium metal anodes, LLZO, phase&#8208, field simulation, solid&#8208, state electrolytes
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要