摘要摘要: 锂离子电池是目前应用最广泛的能量储存和转换装置，富锂氧化物备受关注，三元正极材料也有很大的发展前景，工作电压范围大，好的热稳定性。但实际上它还是存在一些问题，从而阻碍了进一步的应用，比如锂离子扩散能力差，导电率差等。PVP能纳米化减小锂离子的扩散途径，作为表面活性剂提高导电率，很好的解决了锂离子脱嵌问题，增强锂离子扩散能力，降低电极极化。本次实验采用水热法合成，并添加PVP合成三元正极材料并对其进行改性研究，得到PVP能很好地改善正极材料电化学性能。另外，本次实验通过改变反应时间、烧结温度、溶剂等各种实验参数，采用循环伏安测试和交流阻抗等电化学表征手段，对比分析各条件下的电化学性能，进而制定出更优的合成工艺，得出了PVP溶剂为乙醇、反应时间为10h、烧结温度为700℃下制得的Li[Li0.12Mn0.54Ni0.13Co0.13]O2 性能最佳。40973
关键词：锂离子电池；三元正极材料；水热法；PVP；循环伏安；合成工艺
Abstract
Abstract: Lithium ion batteries are currently the most widely used energy storage and conversion devices, lithium-rich oxide is concerned, due to its large operating voltage range, good thermal stability, ternary cathode material also has great prospects for development. But in fact it still has some problems, which hinder the further application, such as the poor lithium ion diffusion rate and poor electrical conductivity. PVP can reduce nano diffusion path of lithium ions, as a surfactant to improve conductivity, a good solution to the problem of lithium ion deintercalation enhance lithium ion diffusion capacity, reduce electrode polarization. During this experiment, we added PVP ternary cathode material by hydrothermal synthesis method,  and its modification to obtain PVP can greatly improve the electrochemical properties of the cathode material. In addition, by changing various experimental parameters such as reaction time, sintering temperature, solvents, we used cyclic voltammetry and electrochemical impedance spectroscopy characterization methods to  make comparative analysis of electrochemical performance under all conditions, and then to develop a better synthesis. In conclusion, when PVP’s solvent is ethanol, the reaction time is 10h, the sintering temperature is 700 ℃ , the Li [Li0.12Mn0.54Ni0.13Co0.13] O2  obtained  the best performance.
Keywords: Lithium-ion battery; ternary cathode material; hydrothermal; PVP; cyclic voltammetry; Synthesis
 目录
1．绪论    1
1.1锂离子电池的发展现状    1
1.2锂离子电池工作原理    1
1.3锂离子电池正极材料的研究现状    2
1.4 锂离子电池正极材料的合成方法    3
1.4.1高温固相法    3
1.4.2共沉淀法    3
1.4.3溶胶－凝胶法    3
1.4.4水热法    4
1.4.5其他方法    4
1.5 PVP对正极材料的改性    4
1.5.1 PVP作为碳源改性研究    4
1.5.2 PVP作为表面活性剂改性研究    5
1.6选题目的、内容及意义    5
2．实验药品及仪器    6
2.1实验药品    6
2.2实验仪器    7
3.实验原理及测试方法    7
3.1实验原理    7
3.2测试方法    8
3.2.1工作电极制作    8
3.2.2三电极测试系统循环伏安测试    8
3.2.3循环伏安测试(CV)    8
4.实验与表征    9
4.1 样品制备    9
4.2.不同反应时间对水热法三元正极材料的合成及表征    9 PVP对三元材料的影响:http://www.751com.cn/cailiao/lunwen_40863.html