Adding lithium fluoride to improve the electrochemical properties SnO2@C/MWCNTs composite anode for lithium-ion batteries

In this paper, SnO2@C/MWCNTs-lithium fluoride (LiF) composite electrode was prepared. Carbon-coated SnO2 (SnO2@C) was prepared by spray drying method with water-soluble asphalt as the carbon source and multiwalled carbon nanotubes (MWCNTs) as conductive agent. The electronic conductivity of the new type of anode was significantly enhanced and the volume expansion of SnO2 was refrained. LiF was utilized to enhance the stability of the SEI film and improve the coulombic efficiency and capacity retention rate of electrode. After 200 cycles, the SnO2@C/MWCNTs-LiF anode still maintain 70.1% capacity retention rate. And the specific capacity hold at 274 mAh/g at 2400 mA/g compared with 136 mAh/g of SnO2@C/MWCNTs anode. The results demonstrated that the addition of LiF can stabilize the SEI film and improve the electrochemical performance of the lithium-ion batteries (LIBs).