LiNi 0.5-x P 2x Mn 1.5-x O 4 (x = 0, 0.005, 0.01, and 0.02) submicrograins in regular octahedral shape with merely {111} surface facets and truncated octahedral shape with both {111} and {100} surface planes were obtained by the solid-state reaction method. The effect of doping P on ions arrangement, grain morphology, and the electrochemical performance of lithium nickel manganese oxide was investigated. The characterizations of X-ray diffraction (XRD), Raman, X-ray photoelectron spectroscopy (XPS), and selected area electron diffraction (SAED) confirm more Mn 3+ ions in the structure to enhance the cationic disorder degree of LiNi 0.5 Mn 1.5 O 4 after Pdoping. Comparing the LiNi 0.5 Mn 1.5 O 4 and LiNi 0.495 P 0.01 Mn 1.495 O 4 samples both with regular octahedral morpology, their electrochemical performance could be remarkably improved by more disordered transition metal ions arrangement leading to higher conductivity of Li-ions and electrons. However, when the amount of P-doping further increased, the rate and cycle ability of the LiNi 0.480 P 0.04 Mn 1.480 O 4 sample in truncated octahedral shape worsen dramatically even with a higher degree of cationic disorder. This could be on account of the crystal planes starting to dominate the electrochemical performance instead of ions arrangement under high voltage and large rate: the {111} facet is more favorable to the lithium ion transport than the {100} crystal plane for LiNi 0.5 Mn 1.5 O 4 submicrograins during charge and discharge.

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LLZO coated LiMn1.95Ni0.05O3.98F0.02 with controllable microstructure and crystallinity was prepared and studied.