However, P2-NaS0.10NMO exhibited a larger change in the radial distance compared to the P2-NaNMO material. The P2 to O2 phase transition experienced by the P2-NaNMO material has some small benefits related to limiting the change in radial distance between TM-O, but overall, the phase change is not beneficial due to the global change in lattice parameters. As for P2-NaM0.10NMO, it showed the smallest changes among the three samples in the high voltage region due to a less pronounced oxygen redox and moderate phase transition. In the shell of Ni-Me, P2-NaNMO and P2-NaS0.10NMO also showed a clear change in the high voltage region, but these changes were quite small, which can be related to the inactive Mn in these compositions. Moreover, the curves for P2-NaNMO and P2-NaM0.10NMO in the discharged state can coincide with the OCV state, further demonstrating that the reversibility is higher than that of P2-NaS0.10NMO in the first cycle.