低温处理中间相沥青炭微球的充放电性能研究

CHARGE-DISCHARGE PERFORMANCE OF MESOCARBON MICROBEADS HEAT-TREATED AT LOW TEMPERATURES

研究了在 5 0 0～ 10 0 0℃下停留不同时间低温炭化处理的中间相沥青炭微球 (MCMBs)的充放电性能 ,并与其XRD结构相关联。研究表明 :在 5 0 0～ 10 0 0℃停留 4h炭化处理的中间相炭微球中 ,70 0℃炭化处理的MCMBs充放电性能最好 ,充放电容量最高 ,不可逆容量损失最小 ;在 70 0℃炭化温度下停留时间的延长有利于MCMBs循环性能的提高。

Mesocarbon microbeads (MCMBs) 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 temperatures from 500 ℃ to 1 000 ℃. It was found that the MCMBs heat treated at 700 ℃ has the best charge discharge performance. The longer the heat treatment time is, the higher the charge capacity is and the lower the irreversible capacity loss is, but the discharge capacities have little difference, which is about 350 mA·h/g. From the practical view, the prolongation of heat treatment time at 700 ℃ will lead to further improvement of the irreversible capacity.