Preparation and Modification of Mesocarbon Microbeads Materials Using Magnetic Rotating Thermal Plasma Processing

Mesocarbon microbeads (shortened by MCMB) are excellent precursors for preparing high-strength and high-density graphite materials, which can be treated by high temperature to achieve high quality carbon-based materials. At low pressure, about 10 Pa, by using Magnetic Rotating Thermal Plasma (shortened by MRTP) processing technology, MCMB can be rapidly heated to the high temperature at more than 3200 K in few minutes. The vacuum environment is beneficial for the precipitation of volatile substances in raw MCMB, meanwhile high temperature is conducive to the rearrangement of internal structures, which means significant improvement of graphitization. Thus, it is shown that the volume of MCMB sample treated by MRTP processing decreases, while its density and purity increase, especially the latter changed from 70 to 94%. Subsequently, the results of charge–discharge test of batteries made by the treated sample show that the discharge capacity is up to 360 mAh/g, while through the composition with Si powder can improve the performance to 1200 mAh/g. The MRTP processing made the surface of MCMB particles disordered, and gave rise to an improvement in the thermal stability and electrochemical properties of the powders. It also made the powders suitable for further use in energy-storage materials.