| Spinel LiMn2O4 compaosite cathode for Li-ion battery was synthesized by simpale and high temperature solid-reaction method using Li2CO3, different chemic manganese oxide (provided by Chemical Academe of Hunan Province) as raw material. The preparation of technics of the Spinel LiMn2O4 was investigated by XRD and SEM. The electrochemical property was also investigated by charge-discharge test and CV. The Spinel LiMn2O4 nanorods were synthesiszed in the same way. The different MnO2 was provided by the chemical academe of Hunan province:The best way of synthesize Spinel LiMn2O4 was at the condition of that calefactive at 5℃/min,780℃/36 h, the proportion of Li/Mn was 1.2:2, rubbing 2h, and the D50 of MnO2 was about 50μm The galvanostatic charge-discharge measurements of the materials were investigated under a current rate of 0.2 C with the cutoff voltage between 3.0 and 4.4 V. The fist discharge of Spinel LiMn2O4 reached 130.9 mAh/g at 0.1 C. The capability of the electrode reached 120.2 mAh/g and 93.4 mAh/g under 0.5C and 1C. The electrode process kinetics of Spinel LiMn2O4 was studied by Cyclic Voltammetry (CV) and Electrochemical Impaedance Spectroscopy (EIS)The results indicated that the electrochemical property, morphology and structure of the Spinel LiMn2O4 were highly related to the calcination tempaerature, different proportion of Li/Mn, calefactive speed, tempaerature decelerate, time of rubbing, different MnO2. At the same time, nanorods of MnO2 synthesized by hydrothermal reaction was fore-material.The result of SEM and XRD were indicated that the outcome of the reaction was right. The first discharge of Spinel LiMn2O4 synthesized form nanorods ofβ-MnO2 was 109.4 mAh/g,102.5 mAh/g and 71.4 mAh/g at 0.5C,1 C and 2C. The result indicated that the Spinel LiMn2O4 nanorod is pure, single-phase and crystalline micro-powders. The performance of electrochemistry showed predominant capability. |
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