本科毕业论文_掺杂钒酸锂做可充锂电池正极材料的研究.doc

题 目: 流变相反应法制备锂二次电池正极材料LiV3-xZnxO8 摘 要 具有层状结构的LiV3O8具有稳定的晶体结构、低成本、高比容量、丰富的原材料以及在空气中稳定存在等特性。因此，近20年来其作为二次锂离子电池正极材料的研究受到了人们的广泛关注。 本文中，采用低温下流变相法掺杂Zn来合成正极材料LiV1-xZnxO8，并对所合成材料的制备条件以及电化学性能进行研究。其主要内容为：称取不同比例的LiOH、NH4VO3和Zn（CH3COOH）2进行研磨，然后加二次蒸馏水调和成流变相于反应釜内80℃保湿6小时之后干燥12小时。研磨后中不同的温度煅烧10小时即得所需产物。通过XRD测试表明通过流变相法成功制备了LiV3-xZnxO8产物。实验表明400℃温度下加热处理10小时得到的LiV3-xZnxO8样品具有的首次放电容量达到257.4 mAh/g，而且其循环性能优良，在经过30周循环以后，其比容量仍能达到236.9 mAh/g。此结果说明与LiV3O8相比，LiV3-xZnxO8中放电比容量和充电性能以及循环性能上表现出了良好的优越性，使得钒酸锂作为锂电池正极材料的性能得到了明显的改善。 关键词：钒酸锂掺杂，流变相反应法，锂离子电池，正极材料 Title Doped vanadium lithium rechargeable lithium battery cathode material Abstract LiV3O8 with layered structure LiV3O8 displays the characteristics stable crystal structure , low-cost, high- capacity, abundant raw materials and stability in the air. Therefore, for the past 20 years, it has been widespread concern as a rechargeable lithium ion battery cathode material. In this paper, the use of low temperature downstream phase method the doped Zn to synthesize the cathode material LiV1-xZnxO8 and the preparation conditions, and electrochemical properties of the synthesized materials research. Its main contents are: Weigh the different proportions of LiOH, NH4VO3 and Zn ( CH3COOH ) 2 grinding , Then add twice-distilled water to reconcile into a theological phase within the reactor 80℃ after 6 hours moisturizing dried for 12 hours . After calcined for 10 hours at different temperatures, the desired product is obtained. By XRD tests show that by the rheological phase was successfully prepared LiV3-xZnxO8 product. The experiments show that the heating treatment temperature of 400 ℃ for 10 hours to obtain the sample of LiV1-xZnxO8 having the initial discharge capacity reaches 257.4 mAh/g，And its excellent cycling performance , after the 30 week cycles , the specific capacity could meet the 236.9 mAh/g . This result is compared with LiV3O8, LiV1-xZnxO8 discharge than the capacity and charging performance and cycle performan