Fig 1

(a, b) SEM morphology of PC-NCM; (c) Li transport pathways and phase transition in NCA; (d) 3D/2D plot of the equivalent stress within the PC-NCM particles upon completion of charging; (e) schematic diagram of PC-NCM structure degradation; (f) relationship between discharge capacity, capacity retention, and thermal stability as a function of Ni ion content in cathodes; (g) the capacity retentions for the PC- and SC-NCM cathodes cycled at 1C; (h) comparison of O2 release from SC-NCM and PC-NCM materials. (a, b) Adapted with permission from Ref. 4, Copyright 2023, Wiley-VCH. (c) Adapted with permission from Ref. 7, Copyright 2021, American Chemical Society. (d) Adapted with permission from Ref. 8, Copyright 2020, Springer. (e) Adapted with permission from Ref. 9, Copyright 2019, Wiley-VCH. (f) Adapted with permission from Ref. 13, Copyright 2019, American Chemical Society. (g) Adapted with permission from Ref. 15, Copyright 2021, American Chemical Society. (h) Adapted with permission from Ref. 18, Copyright 2023, Elsevier."

Fig 2

(a) Apparent lithium diffusion coefficient $ \widetilde{D}_{\text{Li}}^{\text{app}}$ calculated from the Warburg coefficient during the first charge/discharge cycle for PC-NCM and SC-NCM cathodes; (b) schematic diagram of the hierarchical structure of electrode integrated with single- or poly- crystals. (a) Adapted with permission from Ref. 31, Copyright 2021, Wiley-VCH. (b) Adapted with permission from Ref. 32, Copyright 2021, Wiley-VCH."

Fig 3

(a) Sequential differential images of the lithium concentration and phase transition fraction versus time for NCM particle delithiation; (b) three-dimensional mapping of the oxidation state of Ni at the single particle scale; (c) 2D chemical phase mappings of NCM particles at Mn K-edge; (d) three-dimensional in situ BCDI images of LMR particles. (a) Adapted with permission from Ref. 40, Copyright 2021, Springer. (b) Adapted with permission from Ref. 42, Copyright 2021, Springer. (c) Adapted with permission from Ref. 43, Copyright 2021, Springer. (d) Adapted with permission from Ref. 44, Copyright 2022, Springer."

Fig 4

(a) Schematic of NCM lattice distortion; (b) TEM images of NCM particles charged to 4.3 V, and c-axis lattice parameter maps along the ion diffusion path in the particles; (c) dimensional changes of atomic lattice dimensions of a variety of layered and spinel cathode materials during the first cell charge; (d) synchrotron X-ray diffraction and in situ high-resolution XRD of NCM material (003) facets in the first cycle; (e) comparison of lattice parameter changes between pristine NCM and coherent perovskite phase NCM during the first cycle; (f) variation of shear stress c/a during the first cycle. (a, d–f) Adapted with permission from Ref. 47, Copyright 2022, Springer. (b) Adapted with permission from Ref. 29, Copyright 2021, American Chemical Society. (c) Adapted with permission from Ref. 48, Copyright 2022, Elsevier."

Fig 5

STEM images of cation mixing in NCM particles at (a) edge planes, (b) twin boundaries, and (c) intragranular cracks after cycling; (d) 3D open inside view and the corresponding cross-sectional view of 3D nano-stratigraphic imaging in NCM particles after cycling; (e) schematic diagram of Li/Ni mixing; (f) schematic diagram of the nickel "magnetic frustration" phenomenon. (a, b) Adapted with permission from Ref. 63, Copyright 2017, American Chemical Society. (c) Adapted with permission from Ref. 61, Copyright 2021, Elsevier. (d) Adapted with permission from Ref. 43, Copyright 2021, Springer. (e) Adapted with permission from Ref. 64, Copyright 2020, Royal Society of Chemistry. (f) Adapted with permission from Ref. 66, Copyright 2020, AAAS."

Fig 6

(a) SEM image of planar gliding of SC-NCM particles; (b) high-angle annular dark field-STEM (HAADF-STEM) image from around the slicing area. The upper inset is a magnified image of the gliding area enclosed by the red square; (c) X-ray nano-tomography of intragranular cracks in NCM particles after cycling; (d) intragranular cracks in NCM particles after cycling; (e) schematic diagram showing crack formation in the grain interior due to tensile stress (a, b) Adapted with permission from Ref. 76, Copyright 2020, AAAS. (c) Adapted with permission from Ref. 22, Copyright 2020, Springer. (d, e) Adapted with permission from Ref. 78, Copyright 2017, Springer."

Fig 7

(a) Calculation of the partial molar enthalpy of oxygen in NCM111, NCM523 and NCM622 as a function of the change in oxygen vacancy concentration δ; (b) observation of oxygen release behavior during the charging-overcharging stages using isotope18O-labeled online electrochemical mass spectrometry (OEMS); (c) schematic diagram of the correlation between strain generation and O release as well as transition metal migration."

Fig 8

(a) Relative volume changes (with respect to LiCoO2) of SC-NCM particles with different TM element contents are plotted against. Numbers indicate: LiNi0.75Mn0.25O2(602), LiNi0.75Co0.25O2(620), LiNi0.5Mn0.5O2(505), LiNi0.5Co0.5O2(550) and LiNi0.33Co0.33Mn0.33O2(333); morphology and structure of SC-NCM samples with different particle shapes: (b) octahedra, (c) plates, (d) rods; (e) formation mechanism of kinetic reaction pathways during synthesis of single-crystal Co-free Ni-rich oxides. (a) Adapted with permission from Ref. 96, Copyright 2022, Elsevier. (b–d) Adapted with permission from Ref. 109, Copyright 2022, Elsevier. (e) Adapted with permission from Ref. 107, Copyright 2023, Wiley-VCH."

Fig 9

(a) 3D fluorescence mapping of Zr within Zr-doped SC-NCM particles; (b) 2D projection of lattice strain changes on Zr-doped SC-NCM particles; (c) schematic diagram of the correlation between Zr distribution (left, blue curve) and state of charge (right, red curve) in Zr-doped SC-NCM particles; (d) schematic of concentration gradient Zn-doped SC-NCM in the near-surface region; (e) plot of Zn content versus depth in Zn-doped SC-NCM; (f) differential calculated dQ/dV curves of initial charge/discharge profiles of pristine NCM811 and concentration gradient Ta-doped NCM811 electrodes and schematic diagram of Li+ diffusion trajectories under Ta doping; EDS elemental distributions of Al/Zr doped SC-NCM materials (g) and 3D distributions of Ni (h), Al (i), and Zr (j) in SC-NCM photographed by nanometer-resolved 3D X-ray fluorescence. (a–c) Adapted with permission from Ref. 128, Copyright 2021, Elsevier. (d, e) Adapted with permission from Ref. 129, Copyright 2023, Elsevier. (f) Adapted with permission from Ref. 130, Copyright 2021, Wiley-VCH. (g–j) Adapted with permission from Ref. 132, Copyright 2022, Springer."

Fig 10

(a) Mechanistic diagram of the synthesis process of lithium-complemented surface-modified SC-NCM; (b) the point-by-point EDS quantification and (c) the HAADF-STEM image of the layered-spinel intertwined structure in the surface region of SC-NCM; (d) schematic diagram of the stabilized structure modulated by the atomic arrangement control on the surface; (e) TOF-SIMS depth distribution and 3D view of NiO− and PFO2− of PEDOT coated SC-NCM and pristine SC-NCM after 200 cycles; TEM images of pristine SC-NCM (f) and 1% LYTP-coated SC-NCM (g) after 200 cycles. (a) Adapted with permission from Ref. 22, Copyright 2020, Springer. (b–d) Adapted with permission from Ref. 140, Copyright 2023, Wiley-VCH. (e) Adapted with permission from Ref. 142, Copyright 2022, American Chemical Society. (f, g) Adapted with permission from Ref. 145, Copyright 2021, Springer."