Structures and properties of carbon-doped amorphous silicon as anode for lithium ions battery: A first-principles study

Abstract

Silicon-based materials are considered promising candidates for next-generation lithium-ion battery (LIB) anodes due to their high theoretical specific capacity. However, their significant volume expansion during cycling severely limits their application. In the present study, first-principles calculations were performed to study the carbon-doped amorphous silicon as anode. Most interestingly, the results show that the initial doping of carbon in the amorphous silicon led to increased lithium diffusion ability, which is opposite to the result in the carbon doped crystalline silicon. Further structural analysis disclosed that carbon doping enhanced the disorder of the amorphous network which expanded lithium-ion diffusion channels.