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Ti-doped truncated octahedron LiTi<i>_x</i>Mn_2-<i>x</i>O₄ nanocomposites were synthesized through a facile hydrothermal treatment and calcination process. By using spherical aberration-corrected scanning transmission electron microscopy (Cs-STEM), the effects of Ti-doping on the structure evolution and stability enhancement of LiMn₂O₄ are revealed. It is found that truncated octahedrons are easily formed in Ti doping LiMn₂O₄ material. Structural characterizations reveal that most of the Ti⁴⁺ ions are composed into the spinel to form a more stable spinel LiTi<i>_x</i>Mn_2−<i>x</i>O₄ phase framework in bulk. However, a portion of Ti⁴⁺ ions occupy 8a sites around the {001} plane surface to form a new TiMn₂O₄-like structure. The combination of LiTi<i>_x</i>Mn_2−<i>x</i>O₄ frameworks in bulk and the TiMn₂O₄-like structure at the surface may enhance the stability of the spinel LiMn₂O₄. Our findings demonstrate the critical role of Ti doping in the surface chemical and structural evolution of LiMn₂O₄ and may guide the design principle for viable electrode materials.