High-performance anode materials based on anthracite for lithium-ion battery applications

The rise in the price of petroleum coke and needle coke, which are used as anode materials of lithium-ion batteries, has revealed the difficulty of the industry in finding high-performance and low-cost alternatives of these raw materials. In this study, anthracite, a low-cost, high-quality raw material, of which China is rich in resources, was used. After a 2800 °C purification and graphitization treatment, the anode material for lithium battery was prepared. Petroleum coke, as the precursor of commercial graphite, was treated using the same method that was being used for graphitized anthracite, for comparison reasons. The microstructure of anthracite-based anode materials was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy (Roman), and nitrogen adsorption-desorption. Cyclic voltammetry (CV) was used to characterize the electrochemical performance of anthracite-based anode materials by applying constant current charge and discharge (GCD). The experimental results show that the graphitization degree of anthracite-based graphitized anode material can reach 95.44%, with the specific surface area being 1.1319 m²·g⁻¹, and the graphite sheet structure is found to be smooth. The graphitized anthracite, as the anode material of a lithium-ion battery, has a first coulombic efficiency of 87% and a reversible capacity of 345.3 mA·h·g⁻¹ at a current rate of 0.1C, and the material has better lithium storage performance than graphitized petroleum coke material at a high rate. The relatively highly ordered surface structure of graphitized anthracite leads to a better storage performance of lithium. When the current rate returns to 0.1C after different current rates, the capacity has basically no attenuation. After 100 cycles, the reversible capacity retention rate is as high as 93.8%, which is basically equivalent to the rate of graphitized petroleum coke anode while the graphitized anthracite also shows excellent cycle stability. Anthracite-based graphite is equivalent or even superior to graphitized petroleum coke in terms of capacity, rate performance, and cycle stability. This study shows that the use of high-quality anthracite as raw material for the production of lithium-ion battery anode materials has a potential research value and broad commercial prospects.