Mitigating self-discharge of carbon-based electrochemical capacitors by modifying their electric-double layer to maximize energy efficiency

• 作者: Da-Wei Wang Feng Li Hui-Ming Cheng Xu-Yi Shan Yu-Zuo Wang
• 来源期刊: 能源化学
• 年，卷（期）: 2019,（11）
• 页码范围: 214-218
• 页数: 5页
• 语种: 英文

摘要

Self-discharge is a significant issue in electric double layer energy storage,which leads to a rapid voltage drop and low energy efficiency.Here,we attempt to solve this problem by changing the structure of the electric double layer into a de-solvated state,by constructing a nano-scale and ion-conductive solid electrolyte layer on the surface of a carbon electrode.The ion concentration gradient and potential field that drive the self-discharge are greatly restricted inside this electric double layer.Based on this understanding,a high-efficiency graphene-based lithium ion capacitor was built up,in which the self-discharge rate is reduced by 50％ and the energy efficiency is doubled.The capacitor also has a high energy density,high power output and long life,and shows promise for practical applications.