中间相炭微球的结构对其电化学性能的影响

来源期刊：中南大学学报(自然科学版)2003年第2期

论文作者：王红强 李新海 郭华军 郭永兴 彭文杰

文章页码：140 - 143

关键词：中间相炭微球;负极材料;锂离子电池;容量

Key words：mesocarbon microbeads; negative material; Li-ion battery; capacity

摘    要：为了研究不同结构的炭微球对其电化学性能的影响,用聚合法以煤焦油为原料在添加和不添加炭黑的条件下制备中间相炭微球,用高倍扫描电镜观察了它们的形貌和结构,并且研究了它们作为锂离子电池炭负极材料的电化学性能.研究结果表明,在不添加炭黑的条件下得到“地球仪”型结构;对于这种结构的中间相炭微球,锂离子容易脱嵌,首次放电容量可达298.0 mA·h·g^-1,不可逆容量达48.5 mA·h·g^-1,但循环寿命短;而添加炭黑时得到层状混合结构,这种结构的中间相炭微球首次放电容量较小,为288 mA·h·g^-1,不可逆容量相对较大,为81.3 mA·h·g^-1,但衰减慢,循环寿命长.

Abstract: Mesocarbon microbeads(MCMB) can be used as anode material of Li-ion battery. They have different types of structure in different preparations. In order to study the influence of different structures on their electric performances, MCMBs were prepared form coal tar with or without carbon black. The spheres were observed under higher scanning electron microscopy and their electric performance were examined. The result shows that the spheres prepared without carbon black belong to latitude-like structure and the spheres prepared with carbon black belong to layer combination structure. The former allows higher mobility of the Li-ion and it has larger first discharge capacity 298 mA·h·g^-1 and lower irreversible capacity 48.5 mA·h·g^-1, but it has weaker cycle stability. The latter has lower first discharge capacity 288 mA·h·g-1and higher irreversible capacity 81.3 mA·h·g^-1, but it has longer cycle time.