CHARGE-DISCHARGE CHARACTERISTICS OF THE MESOCARBON MICROBEADS HEAT-TREATED AT DIFFERENT TEMPERATURES

Mesocarbon microbeads (MCMB) is one of the promising carbon materials as anodes for rechargeable lithium batteries among commercially available carbon materials. We have examined the correlation between carbon structures and charge-discharge characteristics of the MCMBs prepared at different heat-treatment temperatures. It was found that the MCMB: heat-treated at 700 degrees C possesses a tremendously high charge-discharge capacity of 750 Ah kg(-1). This suggests that there is another mechanism for the charge-discharge reaction besides a graphite intercalation compound mechanism which is well known. Therefore, we propose a cavity mechanism in which intercrystallite spaces in MCMB are capable of storing lithium species.