摘要
以钛酸锂(Li 4Ti 5O 12)/多壁碳纳米管(MWCNTs)复合材料为负极、活性炭(AC)/镍钴锰酸锂(Li(NiCoMn)O 2)复合材料为正极,组装成混合型电容器并研究其电化学性能。利用扫描电子显微镜(SEM),透射电子显微镜(TEM),X射线衍射仪(XRD),拉曼光谱仪(Raman),热重分析仪(TGA)对电极材料进行分析,通过恒流充放电(GCD)和交流阻抗谱(EIS)研究混合型电容器的电化学性能。结果表明:掺杂适量MWCNTs和镍钴锰酸锂可提高电容器的电化学性能。当MWCNTs质量分数为5%时,在电流密度为0.1 A/g下恒流充放电时比容量达161.5 mAh/g。在0.1~1 A/g时,最大功率密度和最大能量密度分别为993.2 W/kg和52.2 Wh/kg。5000周次恒流充放电循环后,容量保持率在92.2%左右,库仑效率仍有99.1%,展现出较高的能量密度和功率密度,并具有优异的循环性能。
The hybrid capacitors were assembled by using lithium titanate/multi-walled carbon nanotubes composite as anode and activated carbon/nickel cobalt manganese acid lithium composite as cathode.The electrode materials were analyzed by scanning electron microscope(SEM),transmission electron microscope(TEM),X-ray diffractomer(XRD),Raman spectrometer(Raman)and thermal gravimetric analyzer(TGA).The electrochemical performance of hybrid capacitors was tested by galvanostatic charge/discharge(GCD)and electrochemical impedance spectroscopy(EIS).The results indicate that the addition of multi-walled carbon nanotubes and lithium nickel cobalt manganese oxide can greatly improve the electrochemical performance of hybrid capacitors.The hybrid capacitors achieve a specific capacitance of 161.5 mAh/g at the current density of 0.1 A/g with an additive of 5%(mass fraction)multi-walled carbon nanotubes.The maximum power density and energy density reach 993.2 W/kg and 52.2 Wh/kg in the current range of 0.1-1 A/g,respectively.The continuous galvanostatic charge-discharge cycling tests reveal that the hybrid capacitors maintain capacitance rate retention of 92.2%and Coulomb efficiency of 99.1%after 5000 cycles.The hybrid capacitors show an excellent cycle performance with high energy and power density.
作者
陈玮
孙晓刚
胡浩
王杰
李旭
梁国东
黄雅盼
魏成成
CHEN Wei;SUN Xiao-gang;HU Hao;WANG Jie;LI Xu;LIANG Guo-dong;HUANG Ya-pan;WEI Cheng-cheng(College of Mechatronics Engineering,Nanchang University,Nanchang 330031,China)
出处
《材料工程》
EI
CAS
CSCD
北大核心
2020年第1期128-135,共8页
Journal of Materials Engineering
基金
江西省科技厅科研项目(20142BBE50071)
江西省教育厅落地计划项目(KJD13006)
关键词
多壁碳纳米管
镍钴锰酸锂
钛酸锂
活性炭
混合电容
multi-walled carbon nanotubes
nickel cobalt manganese acid lithium
lithium titanate
activated carbon
hybrid capacitor
