The efficient solid electrochemical corrosion prelithiation of graphite and SiOx/C anodes for longer-lasting lithium ion batteries

Abstract

In order to avoid side reactions with liquid electrolyte for the prelithiation method using metal lithium for the improvement of initial coulombic efficiency and prelithiation efficiency, we propose the solid electrochemical corrosion (SEC) of lithium replacing liquid electrolyte with solid electrolyte of lithium phosphorus oxynitride (LiPON) in previous works. However, the low prelithiation rate of solid electrochemical corrosion with LiPON interlayer between anode and lithium hinders its possible large-scale application. Here, an ultrathin film of Bi2O3 is introduced as the interface layer to improve the prelithiation rate of SEC, the prelithiation effects are investigated on both graphite and SiOx/C anodes by morphological, spectroscopic and electrochemical characterizations. The initial coulombic efficiencies of graphite and SiOx/C anodes can be respectively increased by about 5.1% and 9.7% after the prelithiation. The prelithiation efficiency values are as high as 79.3% for graphite and 86.7% for SiOx/C with SEC prelithiation. Our results demonstrate that SEC prelithiation with Bi2O3 interface layer could be applied to improve the capacity and cycling performance of lithium-ion batteries.