磷酸铁锂材料具有良好的热稳定性能和循环性能，低污染和价格低廉等优点，因此受到人们的广泛关注。在锂离子电池的应用上, 此材料被认为是具有很大潜力的锂电池正极材料之一。然而，较低的锂离子扩散系数和电子电导率影响了磷酸铁锂材料大倍率性能。所以需要改变其晶体结构、形貌和尺寸来提升LiFePO4的性能，这些改性方法可以从制备条件和方法来控制。本文主要通过水热合成法配以表面活性剂十优尔烷基三甲基溴化铵（CTAB）和酚醛树脂凝胶（R-F）来辅助合成LiFePO4/C材料，通过X射线衍射（XRD）等表征手段和循环伏安法测试电化学性能来确定其表面活性剂辅助合成的作用，CTAB可以控制LiFePO4的颗粒大小，使其分布均匀。41389
毕业论文关键词: LiFePO4；锂电池正极；十优尔烷基三甲基溴化铵；水热合成法
Research of the Preparation and electrochemical performance of LiFePO4/C materials
Abstruct:Lithium iron phosphate material with good thermal stability performance and cycle performance, low pollution and low price is attracting widespread attention. In the application of lithium ion battery, this material is considered as one of the great potential lithium battery cathode material. However, its power performance is greatly limited by slow diffusion of lithium ions across the two-phase boundary and its low electronic conductivity. Changing the crystal structure, morphology and size to enhance the performance of LiFePO4, these properties can be regulated by different synthetic conditions and methods. The sample in this paper mainly synthesized by hydrothermal synthesis method with surface active agent cetyltrimethylammonium bromide (CTAB) and resorcinol-formaldehyde (R-F) sol-gel polymerization. According to the result of the X-ray diffraction (XRD) or scanning electron microscopy (SEM) characterization methods of materials and cyclic voltammetry electrochemical performance test to confirm the role of surfactant and other factors.
Keywords: LiFePO4；lithium ion battery；cetyltrimethylammonium bromide ；hydrothermal synthesis
目 录
1 课题背景 1
2 文献综述 1
2.1 锂离子电池工作原理 1
2.2 锂离子电池负极材料的概述 2
2.3 锂离子电池正极材料的概述 2
2.3.1 钴酸锂 3
2.3.2 镍酸锂 3
2.3.3 锰酸锂 4
2.3.4 磷酸铁锂 4
2.4 LiFePO4的电化学作用机理 5
2.5 磷酸铁锂正极材料的制备方法 5
2.5.1 固相反应法 5
2.5.2 溶胶—凝胶法 5
2.5.3 微波法 5
2.5.4 喷雾热分解法 6
2.5.6 水/溶剂热合成法 6
2.6 LiFePO4材料的改性 6
2.6.1 掺杂 6
2.6.2 表面改性 7
2.6.3 颗粒纳米化 7
3 研究目的及内容 7
4 实验方案与仪器 8
4.1 原料及药品 8
4.2 仪器与设备 9
4.3 正极材料制备 9
4.3.1 碳壳制备 9
4.3.2 前驱液制备 9
4.4 水热反应 10
4.5 粉末烧结 10
5 材料定性及电化学性能测试 11
5.1 X射线衍射分析 11
5.2 电化学性能 11
5.2.1 测试操作 11 LiFePO4/C磷酸铁锂材料的制备及电化学性能研究:http://www.youerw.com/huaxue/lunwen_41436.html