Amorphous silicon-graphene anodes for lithium ion batteries

Abstract

For the development of the next generation lithium-ion batteries it is primordial to investigate new materials as potential candidates towards the increase of the specific capacity of the anode and the new lighter and efficient cells. In this paper we present our investigation on amorphous silicon (a-Si) deposited by DC-sputtering on top of Single Layer Graphene (SLG) grown by Chemical Vapor Deposition (CVD). Our aim being to improve the mechanical properties of the silicon volume change during charging and discharging cycles, it is found that half cells fabricated with such electrodes can achieve specific capacity values above 2000 mAh/g while avoiding large pulverization phenomena. However, it is also found that the a-Si/SLG interface results in high resistance electrodes and decreases cell performance. We suggest that by improving the a-Si/SLG contact resistance, the performance will further improve.