Abstract: The Ti-doped LiNi_0.5Ti_xMn_1.5-xO₄ (x = 0, 0.01, 0.03, 0.05) cathode materials are synthesized by a Self-polymerization method. The effects of different Ti doping contents on the structure, crystal morphology, and electrochemical performance of LiNi_0.5Mn_1.5O₄ are investigated. The materials are characterized by X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), scanning electron microscope (SEM), and electrochemical tests. The results show that when the Ti doping level is x = 0.03, LiNi_0.5Ti_0.03Mn_1.47O₄ exhibits high crystallographic purity, with truncated octahedral morphology, uniform particle size, appropriate Mn³⁺ content, and a highly disordered FD3m space group. The initial discharge capacities at 0.5 C and 10 C are 134 and 96.5 mAh/g, respectively. After 200 cycles at room temperature under 0.5 C, the discharge capacity is 125 mAh/g, with a capacity retention rate of 93.3%. The rate capability and cycle stability are significantly improved compared to the original LiNi_0.5Mn_1.5O₄.