等离子体辅助球磨Si-C复合负极材料及其电化学性能研究

Electrochemical Performance of Si-C Composites Prepared by Discharge-Plasma Assisted Milling

首次采用介质阻挡放电等离子体辅助高能两次球磨制得Si-C复合材料,其结构为微纳尺度硅颗粒均匀分散于微米级碳基体上.Si-C复合电极首周期循环放电容量为1259 mAh·g-1,20和100周期循环的容量分别为474和396 mAh·g-1.该电极充放电曲线和交流阻抗测试的结果表明,复合材料中的硅和碳均参与锂离子嵌/脱反应,且其电荷传导阻抗明显低于纯Si.

Silicon-carbon （Si-C） composites, with microstructure of multi-scaled Si particles being homogenously dispersed in micro-sized carbon matrix, had been prepared by dielectric barrier discharge plasma assisted two-step milling for the first time. The Si-C composite anode had a discharge capacity of 1259 mAh. g~ at the first cycle, while the capacity retained 474 and 396 mAh. g-~ after 20 and 100 cycles, respectively. Charge-discharge curves and AC impedance response indicated that both silicon and carbon phases in the composite anode were involved during the lithiation/delithiation reactions and the electron transport resistance in the Si-C composite anode was much lower than that in the pure Si anode.