A series of spinel LiAl_xMn_2-xO₄ (x ≤ 0.1) cathode materials was synthesized by controlled crystallization and solid state route with micro-spherical Mn₃O₄ as the precursor. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to analyze the crystal structure of the synthetic material and the microscopic morphology of the particles. It was found that Al³⁺ doping did not change the spinel structure of the synthesized materials, and the particles had better crystallinity. In the charge and discharge test of the synthesized materials, we found that Al³⁺ doping would slightly reduce the discharge capacity, but it could effectively improve the cyclic stability of the material. The initial capacity of LiAl_0.04Mn_1.96O₄ is 121.6 mAh/g. After 100 cycles at a rate of 1 C (1 C = 148 mA/g), the capacity can still reach 112.9 mAh/g, and the capacity retention rate is 96.4%. Electrochemical impedance spectroscopy (EIS) suggests that Al³⁺ doping can effectively enhance the diffusion capacity of lithium ions in the material.