反应物比例在LiFePO4合成上的影响

摘要：由于LiFePO4电极材料具有绿色环保，原材料的来源丰富，比容量高及安全性高等特点，因此是新一代锂离子电池正极材料的首选材料之一。目前已经运用于移动通讯技术、交通运输等领域，因此该种材料在未来拥有良好的发展前景，有大力研究的价值。本论文主要研究反应物比例对于LiFePO4电极材料合成上的影响，利用水热法，首先通过不同物质的量之比的FeSO4•7H2O、H3PO4、LiOH•H2O作为反应物来制备LiFePO4电极材料，然后分别测试其性能，来寻求能制得高性能的LiFePO4电极材料的反应物比例。利用XRD和SEM等手段分析制得的材料的微观结构和形貌,循环伏安法测试其电化学性能。30014
不同的反应物比例之间微小的差异会导致LiFePO4样品不同的成核和结晶度，导致不同的表面形貌，以及不同的电化学性能。通过实验测试，反应物比例为FeSO4•7H2O：H3PO4：LiOH•H2O=1:1.5:2.7的样品S3的电化学性能最优，也是本实验得到的最佳配比。
毕业论文关键词：锂离子电池；LiFePO4；反应物比例
The effects of reactant proportion in LiFePO4 synthesis
Abstract：Because of its environmental protection, the rich source of raw materials, theoretical capacity and high security, LiFePO4 is one of the preferred cathode material of the current lithium ion battery. This kind of material has been used in the mobile communication technology, transportation and other fields, and therefore it has the good development prospect in the future and the value of research. This thesis mainly studies the effects of reactant proportion in LiFePO4 synthesis. LiFePO4 was prepared by using different molar ratio of FeSO4•7H2O, H3PO4 and LiOH•H2O through the hydrothermal synthesis. The structure, morphology and electrochemical performance of the cathode materials were characterized by XRD, SEM and cyclic voltammetry. By testing its performance, the appropriate reactant ratio can be sought to be used to prepare the high performance LiFePO4 electrode.
The LiFePO4 electrode which is prepared by small different reactants ratio would have different nucleation rate, crystallinity, structure, morphology and electrochemical performance. Through the experiment testing, the No.S3sample has the optimal performance whose reactant ratio is FeSO4•7H2O : H3PO4 : LiOH•H2O =1:1.5:2.7. The reactant ratio is also the best proportion in this experiment.
Key Words: Lithium ion batteries; LiFePO4; Ratio of reactants
目录
1    绪论    1
1.1 引言    1
1.2 锂离子电池的工作原理    1
1.3 LiFePO4的晶体结构    2
1.4 LiFePO4充放电机理    3
1.5 磷酸铁锂主要应用问题    3
1.6 磷酸铁锂的改性研究    4
1.7 碳包覆    4
1.8 研究方法和技术线路    5
1.8.1 LiFePO4材料的制备    5
1.8.2 X射线衍射分析（XRD）    6
1.8.3 循环伏安法    6
1.8.4 扫描电子显微分析（SEM）    7
2    课题研究    8
2.1 研究的目的和意义    8
2.2 具体实验方案及设计    8
2.2.1 实验任务    8
2.2.2 实验具体方案    9
2.2.3 实验步骤    9
2.3 实验用仪器、设备的型号及规格    11
2.3.1 实验的主要原料    11
2.3.2 实验主要设备    11
2.4 毕业论文具体工作    12
2.5 毕业论文进度安排    12 反应物比例在LiFePO4合成上的影响:http://www.751com.cn/cailiao/lunwen_25499.html