Porous graphene current collectors filled with silicon as high-performance lithium battery anode

Abstract

Despite the massive success for high energy density, the charge–discharge current rate performance of the lithium-ion batteries are still a major concern owing to inherent sluggish Li-ion kinetics. Herein, we demonstrate three-dimensional porous electrodes engineered on highly conductive graphene current collectors to enhance the Li-ion conductivity, thereby c-rate performance. Such high-quality graphene provides surface area for loading a large amount of electrochemically active material and strong adhesion with the electrode. The synergism of porous structure and conductive current collector enables us to realize high-performance new-generation silicon anodes with a high energy density of 1.8 mAh cm−2. Further, silicon electrodes revealed with excellent current rates up to 5C with a capacity of 0.37 mAh cm−2 for 500 nm planar thickness.