孔道可调控的锂离子电池无定形碳负极材料

Amorphous carbon anode with controllable pores for rechargeab lelithium-ion battery

为满足储能市场对高功率电池的需求,开发兼具高容量和高功率性能的锂离子电池负极材料成为必然趋势。本文通过改变煤基沥青在碳化过程中的空速,考察其对无定形碳材料结构的影响,提高煤基沥青无定形碳材料的电化学性能。应用X射线粉末衍射(XRD)、拉曼(Raman)、N_2吸附-脱附和扫描电镜对所制备的无定形碳材料进行结构表征。通过比容量、库仑效率、倍率、循环性能评判材料的电化学性能。结果表明:可以通过改变气体空速来调控无定形碳材料的孔道和碳层无定形度,实现同步提升容量和倍率性能的效果。当气体空速≥0.5 m/min时,充电容量可达近260 mA·h/g,2C充电容量可达约137 m A·h/g。

In order to satisfy the requirement of distributed energy storage system for high power applications, developing new power anode with high capacity for lithium-ion batteries is necessary. In this paper, a novel anode with controllable pores for rechargeable lithium-ion battery was developed. The structures of the materials were characterized by X-ray diffraction (XRD), Raman, N2 adsorption-desorption and scanning electron microscopy (SEM) methods. The capacity, coulombic efficiency and rate capability were investigated. It has been found that the pores can be controlled by changing the space velocity during carbonization. When the space velocity ≥ 0.5 m·min^-1, the amorphous carbon anode achieved a 0.2C capacity of ~260 mA·h/g and 2C rate of ~137 mA·h/g.