Effects of heat-treatment temperature on the microstructure and electrochemical properties of coal based needle coke were investigated by TG-DTG, XRD, SEM, XPS analysis and the charge/discharge, cyclic voltammetry curves. The graphitization mechanism of needle coke is suggested as well as the Li+ extraction-insertion behaviors. With the heat-treatment temperature increasing, the graphite-like crystal grows continuously attended with a complicated process, including the arrangement of crystal along radial/axial direction, dislocation dispersion among graphite layers, hexagonal carbon formation, crystal edge dispersion and folded graphite layer turning to plane. Meanwhile, the driving-forces are far different for different process. When needle coke is graphitized at 2800 ℃, it exhibits a lower charge/discharge potential and stable charge/discharge platform, and the insertion capacitance of Li+ can maintain at 305mAh/g even after charge/discharged for 40 cycles.%通过考察煤系针状焦在700～2800℃热处理过程中石墨微晶结构的变化规律及其电化学性能,并结合TG-DTG、XRD、SEM、XPS表征方法以及充放电、循环伏安曲线特征,分析了针状焦的石墨化机理及其储锂机制.研究结果表明,随热处理温度的升高,针状焦的类石墨微晶在不断长大的同时,还存在微晶在径/轴向的排列、石墨层间位错线的消失、晶界间C-C六圆环的形成、晶界的消失以及石墨层"褶皱"的平面化等复杂过程,且每个过程的驱动力不同.针状焦经过2800℃石墨化后,可获得较低的Li+充放电电位和稳定的充放电平台,且反复充放电40次后的有效嵌锂容量为305mAh/g.
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