锂离子超级电容器的研究

硕士学位论文论文题目锂离子超级电容器的研究研究生姓名刘旭指导教师姓名郑军伟专业名称高分子化学与物理研究方向超级电容器论文提交日期2012-04-01锂离子超级电容器的研究中文摘要I中文摘要超级电容器是一种高功率密度的无源储能元件，随着它的问世，如何应用好超级电容器，是科技工作者的一个热门话题。超级电容器具有充放电速度快、效率高、循环寿命长、工作温度范围宽、可靠性好等诸多优点，但是与传统的二次电池如锂离子电池相比，超级电容器的能量密度较低。本研究主要通过用传统方法做成了以活性碳为电极的对称性电容器，和以石墨、Li4Ti5O12取代一个活性炭电极的非对称性电容器做了对比，尝试得到能量密度更高、循环寿命更好的超级电容器。主要研究内容如下：（1）采用活性炭为对称性电极，以1mol/LLiPF6/EC+DEC(体积比1:1)为电解液，用不同的正负电极质量比，获得最佳的电容器（2）以改进的固相法得到的Li4Ti5O12材料为基础，研究了TiN表面修饰对其电化学性能的影响。结果表明：表面修饰TiN能够显著提高Li4Ti5O12材料的导电性，倍率性能和循环寿命。（3）以Li4Ti5O12为负极，以石墨为正极，探究出了一种性能更好的体系，得到了比较理想的超级电容器。关键词：超级电容器；活性炭；锂离子二次电池；Li4Ti5O12作者：刘旭指导老师：郑军伟教授Abstract锂离子超级电容器的研究IITheperformanceresearchofLithium-ionsupercapacitorsAbstractSupercapacitorisakindofhighpowerdensityofpassiveenergystoragedevices,alongwithitscomingout,howtoapplysupercapacitorwellisahottopicfortheworkers.Supercapacitorwithchargeanddischargespeed,highefficiencyandlongcyclinglife,wideworkingtemperaturerange,goodreliability,andmanyotheradvantages,butwiththetraditionalsecondarybatterythansuchaslithiumionbattery,supercapacitorenergydensityislower.Thisresearchmainlybyusingtraditionalmethodstomakeittothesymmetryofactivatedcarbonelectrodecapacitor,andwithgraphite,Li4Ti5O12replaceanactivatedcarbonelectrodeasymmetryofthecapacitormadethecontrast,trytogethigherenergydensity,circlelifebettersupercapacitors.Themaincontentsareasfollows:(1)Theactivecarbonelectrodeforsymmetry,with1mol/LLiPF6/EC+DEC(volumeratioof1to1)fortheelectrolyte,withdifferentpositiveandnegativeelectrodethanquality,getthebestcapacitors(2)ToimprovesolidphasemethodgetLi4Ti5O12materialsasthefoundation,studytheTiNsurfacemodificationontheelectrochemicalperformanceinfluence.TheresultsshowthatsurfacemodificationTiNcanobviouslyimprovetheconductivityoftheLi4Ti5O12materials,rateofperformanceandcirclelife(3)ToLi4Ti5O12fornegativewithgraphiteaspositive,exploreaperformancewithbettersystem,obtainedtheidealsupercapacitors.Keywords:Supercapacitors；Activecarbon；Li-ionbattery;Li4Ti5O12WrittenbyXuLiuSupervisedbyProf.JunweiZheng目录第一章绪论·····················································································11-1超级电容器概述········································································11-2超级电容器的介绍·····································································41-3混合型超级电容器研究进展·························································101-4锂离子电池简介········································································141-5锂离子电池的组成及工作原理·······················································161-6锂离子电池主要材料的研究现状····················································171-7本论文的研究目的及设想····························································19参考文献·······················································································20第二章有机体系碳基双电层电容器的性能研究···········································242-1前言····················································································242-2实验部分·················································································262-3结果与讨论··············································································262-4小结····················································································29参考文献·······················································································29第三章锂离子电池负极材料Li4Ti5O12的合成及性能研究····························313-1尖晶石型Li4Ti5O12负极材料的研究现状··········································313-2实验部分··················································································353-3结果与讨论···············································································363-4小结·····················································································41参考文献·······················································································42第四章Li4Ti5O12/Graphite混合型电容器的充放电研究································444-1前言····················································································444-2实验部分·················································································454-3结果与讨论··············································································464-4小结····················································································51参考文献·······················································································51总结···································································································53致谢································································································54锂离子超级电容器的研究第一章1第一章绪论1.1超级电容器概述能源是人类社会生存和发展的基础，发展新能源、研究新材料是21世纪亟待解决的重大课题。由于石油资源日益短缺，并且燃烧石油的内燃机尾气排放对环境的污染越来越严重（尤其是在大、中城市），人们都在研究各种类型的新型储能装置。已经进行了混合动力、燃料电池、化学电池产品的应用及研究与开发，取得了一定的成效。随着微电子技术的迅猛发展，各种计算机和微型数码产品有关的电子设备、医疗设备、家用电器及移动通讯设备的逐渐普及，对高性能存储设备用电源的需求越来越严格。但是由于它们固有的使用寿命短、温度特性差、化学电池环境污染、系统复杂、造价高昂等致命弱点，一直没有很好的解决办法。而超级电容器以其优异的特性扬长避短，可以部分或全部替代传统的化学电池用于车辆的牵引电源和启动能源，并且具有比传统的化学电池更加广泛的用途。这些储能装置除对能源密度有一定要求外，对功率密度的要求越来越高。传统电容器虽然可以提供非常大的功率，但其功率密度极其有限，不能满足实际需要。同时随着科技和社会的发展，许多场合如电动汽车等对电源功率的要求越来越高，也远远超出了当今电池的承受能力。在此背景下，超级电容器以其自身的优势引起了越来越多研究人员的关注。电容器是一种能够储蓄电能的设备与器件，由于它