Transport properties of garnet-type Lithium lanthanum zirconium oxide solid-state electrolytes for Lithium batteries

To address the safety problems of lithium-ion batteries mainly caused by to flammable liquid electrolytes, all-solid-state-lithium-batteries (ASSLBs) with solid-state electrolytes are considered as potential replacement candidates. For ASSLBs, inorganic solid-state electrolytes are preferred mainly due to their wide temperature operation windows, better Li mobility and safety. Among the popular solid-state electrolytes, Li7La3Zr2O12 (LLZO) with a garnet structure has been shown to have favorable properties. Understanding the transport properties of Li atoms in LLZO is very crucial because the diffusion mechanism of Li atoms dictates the ionic conductivity among other factors. The main goal of this Muon study is to quantify the Li diffusion rates in LLZO and its interface with cathode with respect to the Grain boundary concentration and morphology.

针对主要由易燃液态电解质引发的锂离子电池安全隐患，采用固态电解质的全固态锂电池（all-solid-state-lithium-batteries，ASSLBs）被视为极具潜力的替代方案。对于全固态锂电池而言，无机固态电解质因具备宽工作温度窗口、优异的锂离子迁移率与安全性能而更受青睐。在主流固态电解质中，具有石榴石结构的Li₇La₃Zr₂O₁₂（LLZO）已被证实具备优异性能。厘清LLZO内锂离子的输运特性至关重要，因为锂离子的扩散机制是决定其离子电导率等关键性能的核心因素。本项μ子（Muon）研究的核心目标是，针对晶界浓度与形貌特征，量化LLZO内部及其与正极界面处的锂离子扩散速率。