| Tremendous efforts are underway on the lithium manganese oxides which are considered to attractive alternatives in term of cost, abundance and nontoxicity for lithium ion battery. The spinel Li4Mn5O12 and cation-doped lithium manganese oxides were synthesized by sol-gel method which is considered as a promising method. Based on the theoretical analysis and experimental study, the influence of technological conditions on the properties of product was systematically investigated by modern analytical methods of BET, XRD, SEM, ICP, TEM, TGA-DTA and so on. And the electrochemical properties of products were studied and the materials show good electrochemical properties.The characteristic of different products at different calcinating temperatures and time, pH value of solution, raw materials were investigated. The results show that perfect spinel Li4Mn5O12 crystals whose size belongs to nanometer can be obtained from the precursor of lithium manganese oxides after being calcinated. It is founded that calcinating temperature has great influence on the crystal structure of Li4Mn5O12 and the optimized temperature is 500℃. And the suit pH value of solution is pH=9.0.In order to improve the electrochemical properties Li4MxMn5-xO12 (M=Al, Mg, Co, Cu, Zn, Sn, Ce) were synthesized by amelioratived technique. The influence of doping elements and differentx has been investigated.The electrochemical performance such as charge-discharge properties, cyclic voltammetry and impedance of products were tested and analyzed. Li4Mn5O12 show good properties with 154.5 mAh/g capacity and good cyclic property. The process of Li+ inserted/extracted in lithium manganese oxide was discussed. Co-doped product shows better cyclic property than Li4Mn5O12 and has greater change current density.
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