KCl-Modified Graphite as High Performance Anode Material for Lithium-Ion Batteries with Excellent Rate Performance

Abstract

Electrochemical properties of a graphite negative electrode of lithium-ion batteries have been enhanced by treating raw graphite with alkali molten salt. Here, the KCl-modified graphite is fabricated via a simple and low-cost technique in which graphite particles and potassium chloride are simply mixed with deionized water and sintered. Compared to the raw material, the rate capability of the graphite modified by potassium is enhanced significantly to 269.7 mAh g–1 at 1 C after 200 cycles which effectively solves the main problem to limit the application of the graphite anode for Li-ion batteries in the field of hybrid vehicles. First-principle calculations have been done to analyze the effect of K-ions on the lithium storage capacity of the graphite. This study provides a scientific basis for adopting the K-modified technique to enhance the electrochemical properties of the negative electrode materials.