中文摘要：

在两步高能球磨和酸蚀条件下制得了多孔硅/石墨复合材料,并对其进行碳包覆制成多孔硅/石墨/碳复合材料。通过TEM,SEM等测试手段研究了多孔硅材料的结构。作为锂离子电池负极材料,电化学测试结果表明多孔硅/石墨/碳复合材料相比纳米硅/石墨/碳复合材料有更好的循环稳定性。同时,改变复合体配比、热解碳前驱物、粘结剂种类和用量也会对材料的电化学性能产生较大的影响。其中使用质量分数为10%的LA132粘结剂的电极200次循环以后充电容量保持在649.9mAh·g^-1,几乎没有衰减。良好的电化学性能主要归因于主活性体-多孔硅颗粒中的纳米孔隙很好地抑制了嵌锂过程中自身的体积膨胀,而且亚微米石墨颗粒和碳的复合也减轻了电极材料的体积效应并改善了其导电性。

英文摘要：

The nano-porous Si/graphite composite was prepared via two-step ball-milling followed by etching process. Then carbon coating was introduced to obtain nano-porous Si/graphite/C. The microstructure of the nano- porous silicon material was characterized by SEM and TEM. The results from electrochemical test reveal that nano-porous Si/graphite/C composite exhibits much better cycle performance than nanosized Si/graphite/C composite. On the other hand, it is found that influence of composition, carbon precursor, binder type and content on the electrode performance is remarkable. The nano-porous Si/graphite/C composite electrode containing LA132 binder （10wt%） exhibits a reversible capacity of 649.9 mAh·g^-1 after 200 cycles, with almost no capacity loss. The superior electrochemical characteristics are attributed to suppression of the volume expansion for lithium insertion via nanosized pores in Si particles, and the volume-buffering action as well as excellent electronic and ionic conductivity of carbon materials.