| CuO possesses high theoretical capacity and TiO2gets high cycle stability. As anode materials in lithium ion batteries (LIBs). both of them have broad prospects for development. On the basis of the summary of lithium-ion battery applications and a review of the investigation at home and abroad of CuO and TiO2anode materials, problems such as CuO’s poor circulation stability and TiO2’s low actual cycle capacity need to be solved. Materials’electric properties and cycle stability can be effectively enhanced via controlling their structure, size. In this thesis, we prepared CuO by urea hydrolysis precipitation and hydrothermal methods, and TiO2by template method. The effects of the fabrication technique and its parameters on the structure, size and the electrochemical properties are investigated by modern testing methods, XRD. TG-DTA. ICP-AES. TEM. and SEM. and electrochemical testing of galvanostatic charge-discharge. The content of conductive agent on the electrode performance is also discussed.The results show that the content of conductive agent has an effect on the electrical properties of anode materials. Among the mixed anode material, conductive agent and binder to various mass ratio of85:10:5.70:20:10and55:30:15. quality ratio in55:30:15has the highest capacity and stability. Conductive agent content is too high that the error of anode material capacity increases and the adhesive property decreases, which is not conducive to the fabrication process and performance analysis. In order to enhance the battery cycle performance, Adjusting the content of conductive agent as20%on preparation of mixed electrode, better battery circulation performance can be obtained.Using copper sulfate. copper acetate and copper nitrate as copper sources, prepared CuO-S. CuO-Ac and CuO-N via urea hydrolysis precipitation method respectively. The first discharging and charging specific capacity at0.1C for CuO-N is978.9mAh/g and346.8mAh/g. and the specific capacity is still at340mAh/g after40cycles. The first discharging and charging specific capacity of CuO-Ac and CuO-S are822.0.238.6mAh/g and95.6,211.9mAh/g. and about190mAh/g and145mAh/g after40cycles. CuO of different copper sources. CuO-N has best electrical properties, followed by CuO-Ac and CuO-S.Micron-sized CuO is prepared by Hydrothermal method, and the effects of heating duration on the morphology and properties is also studied. Results show that, the first discharge specific capacity of CuO prepared by different hydrothermal times are all higher than900mAh/g. the longer timed CuO shows better electrical performance along with the increasing of cycle number.24h maded CuO has reversible capacity as400mAh/g after50cycle times, but2h CuO’s specific capacity is less than300mAh/g. Longer hydrothermal timed CuO has more complete morphology of the microspheres and higher porosity, to favor Li+reversibly inserting and extracting of the solid electrolyte interface (SEI) film, to improve the cycle stability.Micron-sized TiO2hollow spheres are prepared using spherical P(St-co-AA) particles as templates. The first discharging specific capacity reaches is of297.5mAh/g, and it maintained at200mAh/g afterawards. The initial discharging specific capacities are of208.8mAh/g,182.3mAh/g,118.5mAh/g and85.6mAh/g according to the rate of0.5C,1C.5C and10C. respectively. Hollow TiO2microspheres has high specific surface area, which is contribute to the diffusion of Li+, and strenghthen the contaction of negative meterials and electrolyte:its higher structural stability, also reduces the volume change during lithium’s extraction and insertion, improving the circulation capacity. |
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