Ptychographic Observation of Lithium Atoms in the Irradiation-Sensitive Garnet-Type Solid Electrolyte at Sub-Angstrom Resolution

Garnet-type solid electrolyte cubic Li₇La₃Zr₂O₁₂ (c-LLZO) emerges as a promising candidate for establishing reliable and high-performance lithium-ion batteries. Its extreme sensitivity to electron irradiation poses a significant challenge in atomically resolving its structure using conventional transmission electron microscopy (TEM) techniques. We demonstrate that the combination of low-dose four-dimensional scanning TEM (4D-STEM) with multislice ptychographic retrieval methodology manages to achieve a sub-Angstrom resolution and the direct visualization of lithium atoms within c-LLZO. The distribution of lithium in depth direction is also obtained. This work provides atomic-scale insights into the distribution of light elements within irradiation-sensitive dense crystals, paving the way for investigating the microstructure-property relationship.