• 文献标题:   Self-Discharge and Voltage Recovery in Graphene Supercapacitors
  • 文献类型:   Article
  • 作  者:   SUBRAMANIAN S, JOHNY MA, NEELANCHERY MM, ANSARI S
  • 作者关键词:   capacitance, electrochemical impedance spectroscopy, electrode, supercapacitor, voltage
  • 出版物名称:   IEEE TRANSACTIONS ON POWER ELECTRONICS
  • ISSN:   0885-8993 EI 1941-0107
  • 通讯作者地址:   Ctr Mat Elect Technol
  • 被引频次:   6
  • DOI:   10.1109/TPEL.2018.2810889
  • 出版年:   2018

▎ 摘  要

Graphene supercapacitor, with its higher energy density and power density, is a promising solution for energy storage in many potential applications. The available energy from supercapacitors for stand-alone applications depends on their self-discharge. The effect of charge redistribution on the self-discharge and voltage recovery of graphene supercapacitors is investigated in this work. The self-discharge mechanism in graphene supercapacitors is found to be a combined effect of ohmic leakage and diffusion-controlled leakage due to charge redistribution. The charging process has a predominant effect on the self-discharge. With a higher initial voltage, the supercapacitors exhibit more self-discharge, but with longer charge holding time, the rate of self-discharge is low. The charge redistribution is attributed due to the difference in the accessibility of electrolyte ions to the electrode surface. A phenomenon of voltage recovery is observed in graphene supercapacitors even after complete discharge due to a charge redistribution mechanism. The voltage recovery increases with increasing charge/discharge current.