Fig 1

(a) NMC composition diagram; (b) Correlation between discharge capacity and thermal stability of layered structure ternary NMC 16. (b) Adapted from Elsevier publisher. "

Fig 2

(a–d) The upper panels are the HRTEM images of NMC 811 surface after exposure to N2, O2, CO2, and water vapor at the gas pressure of 5  ×  10-2  Torr and at the room temperature for 30 min, respectively. The lower panels show the schematic drawing of Li ions evolution in the layered structure under the exposure of each corresponding gas 21. The green dashed lines outline the surface boundaries of NMC811. 1 Torr = 133.322 Pa. Adapted with permission from Ref. 21, Copyright 2020 Springer Nature. "

Fig 3

In the LixNi1+ZO2 system, (a) during the first electrochemical cycle, the oxidation of Ni2+ causes a local collapse of the space, which makes it difficult for the diffusion and re-intercalation of lithium ions 28; (b) Electrochemical cycling performances of LiNi0.7Co0.15Mn0.15O2, LiNi0.6Co0.2Mn0.2O2 and LiNi0.62Co0.14Mn0.24O230. (a) Adapted with permission from Ref. 28, Copyright 2000 IOP Publishing; (b) Adapted from American Chemical Society. "

Fig 4

A schematic representation of the (a) manganese catalyzed degradation of the anode SEI 33; (b) Acidic species induced decomposition of anode SEI components 34. (a) Adapted with permission from Ref. 33, Copyright 2018 IOP Publishing; (b) Adapted with permission from Ref. 34, Copyright 2020 IOP Publishing. "

Fig 5

Schematic representation of the four negative impacts induced by intragranular and intergranular cracks 38. Adapted with permission from Ref. 38, Copyright 2018 the Royal Society of Chemistry. "

Fig 6

Schematic diagram of the formation of a surface-limited doped layer 49. Adapted with permission from Ref. 49, Copyright 2018 the Royal Society of Chemistry. "

Table 1

The electrochemical performance of different cathode materials through the surface confinement doping of different metals."

Fig 7

STEM image of the sample (a) High-angle annular bright field (HAADF) image of the bulk; (b) HAADF image of the near surface; (c) the ABF enlarged image of the surface area in (b); (d) EDS spectrum of Nb and Mn in the HAADF image; (e) surface doping layer; (f) surface doping and Nb-enhanced surface structure 63. Adapted with permission from Ref. 63, copyright 2018 John Wiley and Sons publisher. "

Fig 8

(a–c) STEM-HAADF images to show the surface structure of samples with the increase of Zn content. (a) Coexistence of a spinel phase and a layered phase. (b) Coexistence of the layered phase and the rock-salt like phase. (c) Surface dominated by rock-salt like phase at high Zn content. (d) Schematic illustration for the phase evolution observed on LNMO surface in respond to the change in Zn content 67. Adapted with permission from Ref. 67, copyright 2019 American Chemical Society. "

Fig 9

(a) Scanning transmission electron microscopy-high resolution annular dark field image (STEM-HAADF) of Al-LNMO particles; (b) and (c) enlarged STEM-HAADF images of two areas in (a); (d) Surface schematic diagram of the vacancy occupancy (SVSO) strategy; most of the 16c positions in the outer layer are occupied by foreign atoms; (e) The 16c charge and discharge curves at 1st and 150th; (f) Cycle performance at 0.1C rate 52. Adapted with permission from Ref. 52, copyright 2018 Elsevier publisher. "

Fig 10

(a) Transmission diagram of NMC811ZO–800 ℃; (b) Relationship between surface Zr content (XPS test result) and temperature; (c) The relationship between Zr content and the distance from the surface of particles (NMC811ZO-450 ℃ and NMC811ZO-800 ℃) to the interior; (d) Cycle performance of uncoated NMC811 and ZrO2 coated NMC811ZO-450 ℃ and NMC811ZO-800 ℃ at 30 ℃ 70. Adapted with permission from Ref. 70, copyright 2017 John Wiley and Sons publisher. "