摘要本文设计了锂离子电池的钛酸锂基负极材料的改性研究,采用双离子取代反应8TiO2+N2O3+2MO+6LiOH•H2O→2Li3Ti4MNO12对尖晶石型钛酸锂Li4Ti5O12进行改性。运用纳米合成工艺及高温煅烧的反应原理,制备出形貌规则、粒径一致性好的Li3Ti4MNO12负极材料,并通过X射线衍射(XRD)、扫描电子显微镜(SEM)表征合成材料的物相组成、形貌特征,通过充放电循环测试、循环伏安法(CV)和阻抗表征合成材料的电化学性能。本实验中选用751组不同的二、三价离子组合(Ni、Cr;Ni、Fe;Ni、Al;Ca、Cr;Mg、Cr;Co、Al)分别制备出Li3Ti4NiCrO12、Li3Ti4NiFeO12、Li3Ti4NiAlO12、Li3Ti4CaCrO12、Li3Ti4MgCrO12及Li3Ti4CoAlO12,以探寻最合适作为钛酸锂取代改性的一组双离子组合。24613
通过实验我们发现Li3Ti4NiCrO12的首次充电比容量为149.1mAh/g,首次放电比容量为159.6mAh/g,与理论充放电比容量156.0mAh/g相近,充放电过程均有明显的平台,具有较高的比容量;通过10次充放电循环,Li3Ti4NiCrO12的放电比容量保持率为99.61%,充电比容量保持率为94.03%,展示出优异的循环稳定性;并且充放电过程中氧化还原峰的间距为0.312V,具有较好的可逆性。
毕业论文关键词: 改性钛酸锂;纳米球磨;喷雾干燥;高温固相法;倍率性能;循环性能
New anode material based on Li4Ti5O12
Abstract
This article design new modified anode material based on Li4Ti5O12 of lithium ion battery. The substitution 8TiO2+N2O3+2MO+6LiOH•H2O→2Li3Ti4MNO12 has been tested in the spinel-type lithium titanium oxide Li4Ti5O12. The use of nano-reaction principle of synthesis and calcination prepared morphology rules, the consistency of good Li3Ti4MNO12 diameter anode material, and by X-ray diffraction analysis, scanning electron microscopy to characterize the phase composition of the synthesized product, morphology characteristics, the charge discharge cycle, cyclic voltammetry and impedance measurements to characterize the electrochemical properties of the synthesized product. In this experiment two different groups selected six trivalent ion composition (Ni, Cr; Ni, Fe; Ni, Al; Ca, Cr; Mg, Cr; Co, Al) prepared Li3Ti4NiCrO12, Li3Ti4NiFeO12, Li3Ti4NiAlO12, Li3Ti4CaCrO12, Li3Ti4MgCrO12 and Li3Ti4CoAlO12, to explore the most suitable doped lithium titanate as a set of dual ion composition.
We found that initial charging capacity of Li3Ti4NiCrO12 was 149.1mAh/g, the initial discharge capacity was 159.6mAh/g, slightly higher than the theoretical charge-discharge capacity of 156.0mAh/g. Charge-discharge process are obvious platform with high specific capacity; through 10 charge-discharge cycles, Li3Ti4NiCrO12 discharge capacity retention ratio was 99.61%, the charge capacity retention ratio was 94.03%, demonstrating the excellent cycle stability; discharge process and the spacing redox peak is 0.312V, show a good reversibility.
Keywords: Li3Ti4MNO12, nano-milling, spray drying, high-temperature solid-state reaction, rate performance, cycle performance
目 录
第一章绪论 1
1.1引言 1
1.2 锂离子电池简介 1
1.2.1 锂离子电池发展状况 1
1.2.2 锂离子电池的结构和工作原理 2
1.2.3 锂离子电池负极材料 3
1.3 锂离子电池负极材料Li4Ti5O12的研究进展 4
1.3.1 Li4Ti5O12结构和电化学性能 4
1.3.2 Li4Ti5O12的制备方法 5
1.3.3 Li4Ti5O12的改性研究 6
1.4 课题的主要内容 7
1.4.1 课题研究的目的和意义 7
1.4.2 课题研究内容 8
1.4.3 实验方案设计 8
第二章实验及表征 9 钛酸锂基负极材料的研究+文献综述:http://www.751com.cn/cailiao/lunwen_18202.html