中文摘要：

以煤焦油为原料在天然石墨球表面包覆一层中间相炭材料制备出一种复合炭材料。研究了天然石墨球加入量对复合炭材料电化学性能的影响。结果表明：随着天然石墨球添加量的减小，复合炭材料的充放电容量增加，首次充放电效率减小。在200mL煤焦油中加入70g天然石墨时所制备的复合炭材料经70000热处理2h后性能最佳，可逆比容量达378mAh/g，充放电效率为91．3％。复合炭材料的循环性能得到了充分改善，30个周期容量保持率97．04％。

英文摘要：

Natural graphite coated by mesocarbon was prepared by depositing mesocarbon from the coal tar pitch on the surface of natural graphite. The effects of the weight of natural graphite on the electrochemical properties of carbon composite for the anode of lithium ion cells were studied. The results show that the charge-discharge capacity of carbon composite increases and the initial coulombic efficiency reduces with the decrease of weight of natural graphite. The sample of appending 70 g natural graphite to the coal tar pitch of 200 mL and heat-treated at 700 ℃ for 2 h has the best electrochemical performances with a reversible capacity of 378 mAh/g and an initial coulombic efficiency of 91.3%. The cycling stability of the Li/C cells with carbon composite as anodes is improved, its capacity retention ratio at the 30th cycle is 97.04%.