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With the miniaturization of electronic products, the development trend of portable, micro-battery has broad application prospects in the future of electronic equipment in the field. Currently, micro battery, lithium-ion battery has the advantages of high specific energy, high-voltage, long cycle life, in the field of electric vehicles, mobile communications equipment power, energy storage is widely used and therefore, lithium ion batteries have become the research hotspot. Commercialization of lithium-ion batteries with graphite as the anode material, lower than capacity (330mAh / g), unable to meet in the future development of the battery with high specific capacity needs, and has a layered structure (monolayer or less than 10 layers ) and good electrical properties of graphene (graphene nannosheets), exhibited excellent performance anode material for lithium-ion batteries. Therefore, this paper discusses the preparation and characterization of graphene, expand the corresponding electrochemical performance of its lithium-ion battery anode material. The peeling method is expanded by pyrolysis using the the Hummers oxide Preparation of graphite oxide, the reduction to give the structure of the sheet layer, loose graphene. Microscopic characterization of graphene and charge-discharge cycle performance testing to obtain the specific surface area of ??559.3m2 / g, and the first charge capacity 2180mAh / g, the first discharge capacity 1046.8 mAh / g after 50 cycles of charge and discharge lithium intercalation capacity of 620mAh / g. The data show that graphene showed good cycle performance as a lithium-ion battery anode material. On this basis, by changing the amount of oxidant in the oxidation process, the oxidation time and pyrolysis expansion in the expansion temperature in the stripping process, the reactant mass, and other conditions for process exploration, and by elemental analysis, IR, TGA, XRD, SEM, TEM , Raman, cyclic voltammetry, AC impedance, charge-discharge cycle performance tests obtained optimal synthesis process is low temperature, high temperature oxidation time is 2h, 1h, 30min reduction temperature of 300 ° C. However, in the study of electrochemical properties, graphene as a lithium-ion battery anode material although high charging capacity, and 50 cycles can still get higher and more stable than the capacity, but its first high severe irreversible capacity for the first time coulombic efficiency, and the mechanism of action is not obvious, and needs to be further improved. In summary, the use of pyrolytic graphite oxide expansion peeling a high specific surface area of ??the graphene can be prepared, as a lithium ion battery, the negative electrode material shows better cycling performance. Therefore, as a battery anode material works and preparation of further research on graphene, is expected to be a performance of the electrode materials.
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