Spherical mesophase soft carbon materials with micro-nano composite structure and their applications in lithium-ion batteries

ABSTRACTThis paper is to investigate the mesophase sphere soft carbon material with micro-nano composite structure and its application in the energy-storage Li-ion battery and electrochemical performance of the battery through experimental tests. The results show that the ball diameter is below 10 μm. For button half-cell, the first coulombic efficiency at 0.1C rate is about 87.1%, the ratio that charging capacity of 2C divided by the charging capacity of 1C is 84.8%, and the charging capacity retention rate after 50 cycles at 0.5C rate is 99.9%. For a full battery of 50 Ah, the discharge capacity can still maintain at 80% or more at the 2C or 3C discharging rate, its discharge rate can still reach more than 80% at a temperature of −20℃, and the capacity retention is 97.7% after 500 cycles.