| With the rapid development of electronic apparatus, as well as energy and environmental issues have become increasingly prominent, people have higher requirement to the chemical power. Researching a new generation of high-performance cathode material becomes an important topic. spinel LiMn2O4 is considered as the most promising cathode materials for lithium-ion battery due to its low cost, environmental free. but, the capacity of spinel LiMn2O4 fades rapidly in the charge-discharge cycle process. It has been suggested that the capacity fading is due to Jahn-Teller distortion,dissolution of manganese into the electrolyte and decomposition of the electrolyte. Therefore how to improve the function of the spinet LiMn2O4 having become the hot spot studying.In this paper, spherical precursor materials MnCO3 was prepared through chemical precipitation, through many filtration and incessant optimization, finally found out best technics: the type of precipitation was the Na2CO3, the concentration of reactants were CMnSO4=1mol/L,CNa2CO3=2mol/L the way for titration was drop-shun, and the reaction time is 5h, mix round speed was 100～200r/min, deposit time was 12h, the temperature was 30℃. The spherical precursor materials MnCO3 prepared by best technics had a compact crystal, good sphericity, the density was 1.802g/cm3, granularity distributing was well, Precursor material MnCO3 was heated, Mn2O3 material remained to be the original spherical shape, had the rough surface, and provided a better precursor for preparing spherical anode material LiMn2O4.spherical anode materials LiMn2O4 were synthesised by sintering. Mn2O3 and Li2CO3 materials were mixed by steep ultrasonic oscillation.High-temperature sintering temperature was 800℃, sintered for 24h. Anode materials LiMn2O4 was synthesized were spherical had been proved by SEM, its density could reach 2.234g/cm3, crystal structure were integrated could be proved by X-ray diffraction analysis, the materials was belong to the spinel cubic crystal system, cell parameters (a= 8.2284?), next to the standard cubic crystal system LiMn2O4 the lattice constant (a=8.2402?). crystal structure were integrated. Using a sample, the first oxidation-reduction and then back titration for coordination of the titration method LiMn2O4 a sample of manganese in the average price of valence. the results show that Mn valence higher than the average 3.5. we can see from the samples can inhibit the John-Teller effect by theory. Through electrochemical workstation for CV test showed that the product has good electrochemical reversible. In the voltage range of 2.8～4.4V and at a specific current of 0.2C the spherical anode material LiMn2O4 exhibited first charge quality capacity of 129.63mAh/g, first discharge quality capacity of 129.57mAh/g, and the capacity retention ratio is 87.06% after 100 charge and discharge cycling. compared with the traditional method of preparation of non-spherical LiMn2O4 material shows: spherical LiMn2O4 for the first time the quality of discharge capacity is close to non-spherical LiMn2O4 for the first time the quality of discharge capacity(129.28mAh/g), but after 100 charge and discharge cycling, the spherical LiMn2O4 for the quality of the discharge capacity was more higher than that of non-spherical LiMn2O4, high to 12.51mAh/g.
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