Preparation of anode materials for lithium-ion batteries by spent carbon anode from electrolytic aluminum

This paper aims to explore the possibility of using spent carbon anode residue (SCA) from aluminum electrolysis as anode materials for lithium-ion batteries. SCA of hazardous solid waste is recovered by a two-stage process of "chemical leaching-high-temperature graphitization" to achieve harmlessness and resource treatment. Chemical leaching can increase the carbon purity of SCA-CL from 61.86% to 92.80% and cause the formation of surface holes-defects structure, which serves to shorten the Li+ transmission distance. High-temperature graphitization can increase the carbon purity of SCA-CL-2800 to 99.90% and cause the significant graphite sheet structure, which can increase the conductivity. SCA-CL-2800, used as the anode material for Li-ion batteries, showed the first capacity of 359.1 mAh g(-1) at 0.1 C, the initial coulombic efficiencies of 80.17% and a reversible capacity of 368.6 mAh g(-1) after 50 cycles. Compared with graphite, SCA-CL-2800 exhibited excellent electrochemical performance. It is estimated that the preparation method provides an innovative strategy for recovery and application of similar solid waste.