Three-dimensional porous graphene microsphere for high-performance anode of lithium ion batteries

A stable graphene anode with high storage Li ⁺ capacity for lithium-ion batteries (LIBs) is to be desired for energy storage. In the present paper, a new scalable method is adopted for preparation of three-dimensional porous graphene microspheres (3DGPM) by a template sacrificing method. The 3DGPM were utilized as an anode for lithium ion batteries (LIBs). The macrostructure of the 3DGPM anode was characterized by the scanning electron microscope, transmission electron microscope and X-ray diffraction. As anode for LIBs, the first discharge/charge capacities of the 3DGPM are 851.1 and 402.4 mAh g ⁻¹ at a current density of 0.1 A g ⁻¹ . The 500th discharge capacity of the 3DGPM anode at a current density of 2 A g ⁻¹ is 245.8 mA h g ⁻¹ . Besides, the 3DGPM exhibit low charge transfer resistance and high Li-ion diffusivities. The porous nanospheres of graphene offer voids for volume expansion and pathways for fast electron transfer during repeated cycling. We believe that the specific micro-/nano-hollow microspherical structure is the main origins of their high electrochemical storage Li performance.