摘要硼酸铁锂（LiFeBO3）是目前热门锂离子正极材料之一，而石墨烯在目前各项研究中是最热门的材料。本文采用喷雾干燥法制备材料，以聚阴离子化合物正极材料LiFeBO3为基础材料，为改善其电化学性能而进行研究。主要探索掺杂不同含量的石墨烯对硼酸铁锂正极材料电化学性能的影响。62212
本文采用纳米球磨结合喷雾干燥法在保护气氛下高温煅烧后得到合成LiFe0.995Cr0.005BO3正极材料。合成过程中，不同含量石墨烯以无水乙醇作为分散剂分散后加入。实验结果表明，石墨烯掺杂有助于提升LiFeBO3正极材料电化学性能。在最佳煅烧温度500℃，保温时间10h条件下，掺杂1%含量石墨烯LiFe0.995Cr0.005BO3锂离子正极材料首次放电比容量最优，达到174.3mAh/g（充放电倍率设定为0.1C，电压为1.5V-4.5V之间），样品制备的电池在0.1C倍率下经过50圈充放电循环后样品放电比容量为164.3mAh/g，其保持率为94%。
毕业论文关键词：硼酸铁锂；锂离子电池；石墨烯；放电比容量；电化学性能
Abstract Lithium iron borate is one of the popular lithium-ion cathode materials, and recently graphene is one of the most popular materials in the research as well. LiFeBO3 based materials, as polyanionic compound cathode material, were prepared by spray drying and its electrochemical properties were investigated. The influence of different levels of graphene doping on the electrochemical properties of lithium iron borate cathode material was explored.
In this paper, LiFe0.995Cr0.005BO3 was synthesized by nano-milling combined spray drying method and then calcined in protection atmosphere. Different amount of grapheme was added during the synthesis procedure, using anhydrous ethanol as disperser. The results show that adding grapheme could effectively improve the electrochemical properties of LiFe0.995Cr0.005BO3 cathode materials. The highest discharge capacity, 174.3 mAh/g (at 0.1C ), was achieved by 1% grapheme doping LiFe0.995Cr0.005BO3 sample, which was calcined at 500℃ for 10 hours. After 50 cycles at 0.1 C, its retention of discharge capacity was 94%.
KeyWords：LiFeBO3；Lithium ion battery；Graphene；Discharge specific capacity；Electrochemical properties
目录
1 绪论··1
1.1 锂离子电池的发展 1
1.2 锂离子电池的应用 2
1.3 锂离子电池的原理 2
1.4 锂离子电池正极材料 3
1.4.1 LiCoO2 3
1.4.2 LiNiO2 4
1.4.3 LiFePO4 4
1.5 石墨烯的结构和性质 4
1.6 硼酸盐正极材料的研究 5
1.6.1 结构 5
1.6.3 金属离子掺杂 6
1.6.4 聚合物包覆 6
1.6.5 量子化学计算 7
1.7 研究背景、主要内容及意义 7
1.7.1 研究背景 7
1.7.2 研究内容 7
1.7.3 研究意义 8
2 样品制备9
2.1 实验设备 9
2.2 实验材料 10
2.3 样品制备过程 铬掺杂硼酸铁锂石墨烯复合正极材料研究:http://www.751com.cn/cailiao/lunwen_68346.html