A high specific capacity anode with silicon enclosed in RGO sphere by using lyophilization for lithium-ion battery

摘要

We report a novel spherical rGO-enclosed SiNPs (rGO/SiNPs) anode for lithium-ion batteries with high capacity and superior recyclability. Here, the high-capacity Si nanoparticles (SiNPs) are enclosed in spherical rGO sheets by lyophilization method. The rGO spheres which cross-link with each other to form the stable conductive framework, provide enough space for volume expansion of SiNPs during the process of lithium-ion intercalation. Meanwhile, the rGO spheres can prevent electrolysis consuming silicon continuously to keep the capacity retention. It shows that in a half-cell test, a high specific capacity (1444.45 mAh/g in initial cycle) and recyclability (993.06 mAh/g after 500 cycles) are achieved.