A facile approach for regeneration of graphite anodes from spent lithium-ion battery

Abstract

Recycling of lithium-ion battery anodes has become a topic of interest due to the retirement of batteries. However, existing recycling methods have either been environmentally unfriendly or lacked high purity levels. Here, a simple and low-cost recycling method is developed. Firstly, organic matter in graphite is eliminated through heat treatment. The removal of metal impurities in graphite is then carried out by utilizing sulfuric acid (H2SO4) leaching. Lastly, potassium hydroxide (KOH) etching is utilized to restore the structural defects of graphite. This comprehensive process enhances the cycling stability and rate capability of graphite. The initial discharge capacity at 0.1 C can reach a specific capacity of 422.42 mAh/g, and the specific capacity of the discharge after 100 cycles is 365.97 mAh/g, which reaches the standard of commercial graphite (CG). The results demonstrate that the method effectively purifies and regenerates waste graphite (WG). This process can alleviate resource pressure while being suitable for industrial applications due to its simplicity and low cost.