3D Imaging of lithium vacancy clusters in a Li-ion battery cathode material

Understanding the ion transport mechanisms at the atomic scale is crucial for the development of next-generation batteries. Yet, atomic level characterization of Li-ion diffusion has been challenging, especially in three-dimensions (3D), due to its weak scattering nature and beam sensitivity [1]. We address this problem using multi-slice electron ptychography (MEP) [2], a scanning transmission electron microscopy (STEM) technique, to elucidate variations in Li distribution within Li-Ni_1/3Mn_1/3Co_1/3O₂ (NMC-111) in 3D, at the level of individual atomic columns. Experimentally detected Li vacancies inside the cathode material will be presented. These findings show the potential of MEP to track the Li distribution in 3D that will benefit our comprehension of Li diffusion mechanisms.

[1] S. Lou, Z. Yu, Q. Liu, H. Wang, M. Chen, and J. Wang, “Multi-scale Imaging of Solid-State Battery Interfaces: From Atomic Scale to Macroscopic Scale,” Chem, vol. 6, no. 9, pp. 2199–2218, Sep. 2020, doi: 10.1016/j.chempr.2020.06.030.

[2] Z. Chen et al., “Electron ptychography achieves atomic-resolution limits set by lattice vibrations,” Science, vol. 372, no. May, pp. 826–831, 2021.