Electrochemical conversion of thin layer amorphous carbon to graphite nanosheets as conductive agents for silicon anode

Abstract

Silicon is considered as an ideal high-capacity alloy-type anode material for lithium-ion batteries. To address its inherent issues of volume expansion and poor conductivity, various strategies for preparing silicon composite materials have been developed. However, three dimensional porous structured conductive agents may address these two drawbacks simultaneously. In this work, a thin-layer perylenetetracarboxylic dianhydride-derived carbon (PDC) is electrochemically converted into highly crystalline and porous graphite (PDG), which shows about 2.6 times larger pore volume and 28 times higher conductivity than common conductive agent acetylene black (AB). When used as a conductive agent for nanosilicon anodes, PDG endows the electrode with excellent cycling stability and high-rate performance. This work promises a new kind of conductive agents that significantly improve the performance of silicon-based anodes.