Performance of lithium-ion capacitors using pre-lithiated multiwalled carbon nanotubes as negative electrode

• Main Authors: CAI Man-yuan, SUN Xiao-gang, CHEN Wei, QIU Zhi-wen, CHEN Long, LIU Zhen-hong, NIE Yan-yan
• Format: Article
• Language: zho
• Published: Journal of Materials Engineering 2019-05-01
• Series: Journal of Materials Engineering
• Subjects: pre-lithiatiation; anode; multiwalled carbon nanotubes(MWCNTs); activated carbon(AC); lithium-ion capacitor
• Online Access: http://jme.biam.ac.cn/CN/Y2019/V47/I5/145
• ISSN: 1001-4381; 1001-4381

Pre-lithiated multiwalled carbon nanotube anode was prepared by internal short approach(IS) for 5min, 30min and 60min. Lithium ion capacitors (LICs) were assembled using pre-lithiated multiwalled carbon nanotubes as cathode and activated carbon(AC) as anode. The structure characterization of multiwalled carbon nanotubes and electrodes were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical performance of pre-lithiated multiwalled carbon nanotube electrodes and pure multiwalled carbon nanotubes electrodes were tested by galvanostatic charge/discharge and electrochemical impedance spectrum. The electrochemical tests indicate that the charge-discharge performance of LIC is greatly improved by pre-lithiation of multiwalled carbon nanotubes. The energy density reaches about 4 times over conventional electric double-layer capacitors (EDLCs) at the current density of 100mA/g. The LICs achived a specific capacitance of 57F/g at the current density of 100mA/g with 60min pre-lithiatiation process. The maximum energy density and power density reach 90Wh/kg and 4130W/kg respectively in the current range of 100-3200mA/g. The capacity retention rate remains more than 85% after 1000 cycles. The LIC shows excellent supercapacitor performance.