Figures and give a detailed representation of the Li 1 -Li 0.5 and Li 0.5 -Li 0 phase transitions in the measured LMNO particle. The onset images for both phase transitions (Figures 2B and 2B) highlight the differences in the morphology evolution for each of them. As the integrated intensity of the 115 Bragg peak of the Li 0 phase (Fig. ) correlates with the one of the Li 0.5 phase in Fig. (6% of delithiated phase intensity), these maps are measured at roughly the same degree of charging during the Li 0.5 -Li 0 and Li 1 -Li 0.5 phase transitions. During the first transition, the Li 0.5 phase starts nucleating at multiple sites of the crystal which are localised at the positions previously exhibiting an increased value of the standard deviation of the measured 115 Bragg peak (Supplementary Video 1, scans 5-18). The nucleation points also coincide with sharp localized misorientation heterogeneities which will be discussed in detail later. This leads us to conclude that such nucleation sites are formed at these positions due to high defect concentration which promotes the ion deintercalation and subsequent local phase transformation as was recently suggested . Due to the limitation of the technique, only 2D maps of the particle are obtained and thus it is challenging to conclude on the exact location of the nucleation sites relative to the shape and height of the particle. The morphology evolution in the beginning of the second transition (Li 0.5 -Li 0 ) however is noticeably different. In Figure (scan 34), the 2D map of the forming Li 0 phase matches the map of the full particle (dashed contour). Therefore the delithiation process during the Li 0.5 -Li 0 phase transition proceeds more homogeneously without the formation of distinct nucleation points. This is also supported by the maps during subsequent charging (Figures ) where higher degree of intensity variation is observed for the emergent Li 0.5 phase than for the Li 0 .