The Li1.02YMn2-xO4 (x=0, 0.005, 0.01, 0.02, 0.04, 0.1, respectively) were prepared by solid-state reaction method with raw materials of Li2CO3, electrolytic MnO2 and Y2O3. The influence of the Y3+ doping on the spinel LiMn2O4 were systemically investigated by means of X-ray diffraction (XRD), cyclic voltammetry (CV) and AC impedance, and soon. The results show that when x <= 0.02, Li1.02YxMn2-xO4 has well-developed crystallite, or there is other phase Y2O3. Cyclic voltammogram testing shows that a small amount of Y3+ doping has no influence on the Li+ intercalation-deintercalation process, but as increased the amount of Y3+ doping, the two-step process of Li+ intercalation-deintercalation transforms to one-step. Simultaneity, Y3+ doping decreases the interacting force among Li+ and Li+, and then availably avoids the energy level splitting. The initial discharge capacity of Li1.02Y0.01 Mn1.99O4 is 124.6 mAh g(-1). Its capacity and maintaining ratio after 100 cycles are 112.1 mAh g(-1) and 90.0%, respectively. It explains that Y3+ doping effectively restricts the Jahn-Teller effect and stabilizes the crystal structure. In addition, the conductivity of the samples is clearly improved due to Y3+ doping. (c) 2005 Elsevier B.V. All rights reserved.