The influence of Graphene quality on performance of a Si/Graphene nanocomposite anode

Si/Graphene nanoparticles represent attractive alternative anode materials for Lithium-ion batteries. Graphene nanosheets with different properties, including surface area, defect distance, and charge-transfer resistance, were fabricated and characterised in Si/Graphene nanocomposites formed by static-electric self-assembly then by an in-situ reduction process. Graphene nanosheets that exhibited the highest surface area, the shortest defect distance, and the lowest charge-transfer resistance demonstrated the best overall electrochemical performance, with a high initial discharge capacity of 2692 mAh g−1, good cycling performance of 1135 mAh g−1, at the 200th cycle at the current rate of 0.5 C. This work shows the preferable graphene quality for Si/Graphene nanocomposite anode and provides insights into the design of graphene nanocomposite electrodes, regardless of the graphene synthesis method.