Molten Salt Derived Graphene-Like Carbon Nanosheets Wrapped SiOx/Carbon Submicrospheres with Enhanced Lithium Storage

Main observation and conclusion There is no doubt that SiOx and carbon composite is one of the promising anode materials for lithium-ion batteries owing to its high capacity and rational cycling stability. Herein, we report a sol-gel synthesis followed by molten salt carbonization route to fabricate graphene-like carbon nanosheet wrapped SiOx/C submicrospheres (SiOx/C@2D-C). The in-situ generated carbon nanosheets under molten salt condition can further improve the electroconductivity, restrain the volumetric expansion and guarantee the structural integrity of the electrode. As a result, the as-obtained SiOx/C@2D-C delivers a discharge capacity of 559 mAh.g(-1) at 0.5 A.g(-1) after 200 cycles and 548 mAh.g(-1) at 1.0 A.g(-1) even after 1000 cycles. The full cell assembled with SiOx/C@2D-C as anode and commercial LiFePO4 as cathode can achieve an energy density of 200 Wh.kg(-1) and maintain a capacity of 66.7% after 100 cycles with a working potential of 2.8 V. The approach is simple and cost effective, which is promising for mass production of SiOx-based materials for high energy LIBs. [GRAPHICS] .