▎ 摘　　要

Graphene materials have been proved an advantage for application in energy storage due to the superior electrical conductivities and high surface area. The structure of porous microsphere is reported as an effective way to achieve high energy density and high power density for LiFePO4. It is worthwhile to examine the influence of the combination of graphene and porous structure of LiFePO4 on the performance of Li-ion battery. To this end, graphene-LiFePO4 (G-LFP) composite porous microspheres are successfully synthesized using the as-prepared graphene oxide-Li3PO4 as sacrificial template. The microspheres showed a uniform morphology that 2 mu m LiFePO4 microspheres are wrapped by graphene nanosheets. And the microspheres exhibit the hierarchical structures assembled by nanoparticles. The cathodes made from G-LFP deliver excellent rate performance that hold 72% of the initial capacity at 10 C. The enhanced performance is attributed to the high conductivity of graphene network in composite and its porous structure in favor of lithium ion diffusion.