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Zhou et al. Microstructures 2023;3:2023043 https://dx.doi.org/10.20517/microstructures.2023.38 Page 17 of 23

Figure 12. Li distribution of NMC811 specimens in APT. (A) APT data from a UHV transferred specimen with in-situ delithiation during
the APT experiment. (B) APT data from an air-transferred specimen with the nominal Li composition and without delithiation, possibly
due to the shielding effect of the surface corrosion product. The measurements were performed at a specimen temperature of 60 K and
a pulsed laser energy of 5 pJ. Scale bars in (A and B) are 20 and 50 nm, respectively. Reproduced with the permission of Ref. [85]
Copyright 2022, Royal Society of Chemistry.

Figure 13. APT analysis of corroded LiNi Mn Co O (NMC811) particle. (A) Scanning electron microscope image of the NMC811
0.8 0.1 0.1 2
particles. (B) Schematic illustrations of the APT specimen preparation method. The oxide layer of interest, as a corrosion product, is
shown in orange. (C) 3-D reconstruction of the APT dataset of the tip incorporating the oxide later. (D) 1-D elemental concentration
profile of the NMC oxide product from a cylindrical region of interest with 5 nm in diameter and 50 nm in length. Reproduced with the
[86]
permission of Ref. Copyright 2022, Wiley-VCH GmbH.
a 1-D concentration profile was generated from the region indicated in Figure 13C, as shown in Figure 13D.
This direct evidence shed light on the chemical origin of the NMC811 corrosion, revealing that it is related
to both oxygen and carbon, rather than solely oxygen. Such valuable insights were challenging to obtain
using conventional electron microscopy techniques due to their limited ability to detect light elements. By
employing cryo-FIB and APT in this study, Singh et al. demonstrated the power of these advanced
techniques in providing crucial information on the corrosion behavior of NMC811 particles, which could
[86]
contribute significantly to the development of more stable and efficient battery materials .