In the left panel of Fig. , HRTEM characterisation of a layered oxide cathode after charging shows that pronounced lattice displacements can trigger oxygen loss and TM migration, subsequently leading to a phase transition from the layered structure to the spinel phase . In situ BCDI measurements illustrate that tensile strain starts accumulating preferentially near the particle surface region and gradually expands into the interior of the particle (top-right of Fig. ) , which is also manifested by the predicted distribution of dislocation-induced plastic shear (driven by Li intercalation) in the entire particle after discharge (middle of Fig. ). The inhomogeneous Li concentration distribution and the accumulation of crystal defects significantly affect the structural stability of Ni-rich and Li-rich cathodes, which may ultimately trigger the bulk decomposition of these layered phases. The oxidation state maps obtained through X-ray spectromicroscopy and ptychography reveal that oxygen deficiency persists within the bulk of secondary particles, rather than being limited to the near-surface (a few nanometers) region of the particle (bottom-right of Fig. ) .