A universal matching approach for high power-density and high cycling-stability lithium ion capacitor

Abstract

Lithium ion capacitor is one of the most promising energy storage technologies with a higher power density and a longer cycling lifespan than Li-ion battery, but also a higher energy density than supercapacitor. However, the unbalanced electrochemical performance between the cathode and anode will inevitably result in unsatisfied power density and reduced cycling lifespan, which largely hinders its commercial applications. In order to eliminate the unbalanced kinetic behavior and cycling stability between the cathode and anode, in this study, we propose a practical and universal electrode matching approach for constructing high performance LIC systems. The effect of effective anode potential range on the performance of a typical LIC system was investigated. An optimal anode potential range is determined and then realized through pre-lithiation to pair with cathode, by which a much improved LIC with high energy density, large power density as well as long cycling lifespan is achieved. Based on the above findings, this approach brings some new insights on ideal anode material candidates for future LIC systems.