Fig. 3: Enhanced structural and mechanical stability of the dual-phase d-LNO (600C-6h) composite cathode compared to the single-phase s-LNO.

a Heatmaps of operando SXRD patterns recorded in the first cycle of the two cathodes at 0.1 C in a wide voltage range of 2.70–4.80 V vs. Li|Li⁺. The H2-H3 phase transition region is highlighted with dashed lines. For clarity, background signals from cell components other than the cathode were removed from the plots. b, c Magnified pattern showing the evolution of (003), (107), (018) and (2–10) reflections at high charging states during the first cycle of the two cathodes. d Variation of lattice-c of the layered phases in both cathodes, and lattice-a of the RS phase in d-LNO; the inset shows the 003 peak profiles at 4.3 V during the H2 to H3 phase transition. e Variation of lattice-a of the layered phases in both cathodes. The lattice parameters a₀ (2.877 Å) and c₀ (14.215 Å) of pristine s-LNO are used for calculating the lattice change percentage. TXM images showing three-dimensional reconstructions of cycled secondary particles for s-LNO (f) and d-LNO (h) after 200 cycles, together with internal structure features revealed by a series of cross-sectional slices on selected particles for s-LNO (g) and d-LNO (i), respectively. Source data for (a, b, c, d, e) are provided as a Source Data file.