Prelithiated SiO _x Anode Materials for Fast Chargeable Lithium-Ion Batteries

Abstract

To meet the increased demands for electric vehicles(EV), Lithium-ion batteries(LIBs) requires fast charging capability. Conventional LIBs using graphite anodes (with a theoretical specific capacity of 372mAh g -1 ) have limitations with lithium plating and slow kinetics during fast charging process. To overcome these limitations, many anode materials have been explored in the attempt to replace graphite. Among silicon based anode materials, SiO x is one of suitable materials for fast charging due to its high reaction voltage and high energy density. However, its low initial Coulombic efficiency(ICE) and poor cycle life remain as critical challenges. Herein, we propose prelithiated SiO x materials prepared by dehydrogenation-driven prelithiation of SiO x using LiH to improve the low ICE and poor cycle life. The prelithiated SiO x shows about 85.5 % of ICE and improved long-term cycle performance for over 300 cycles. Also, the prelithiated SiO x anode shows higher charged capacity at high current density. More detailed microstructure and electrochemical properties of the prelithiated SiO x materials will be discussed in this presentation.