石墨负极电化学扫描循环过程的EIS、Raman光谱和XRD研究  

Studies on Graphite Anode During Electrochemical Scan Cycles by EIS,Raman Spectroscopy and XRD

作　　者：庄全超[1,2] 许金梅[1] 田景华[1] 樊小勇[1] 董全峰[1] 孙世刚[1] 

机构地区：[1]厦门大学化学化工学院化学系,固体表面物理化学国家重点实验室,厦门361005 [2]中国矿业大学材料科学与工程学院,徐州221116

出　　处：《高等学校化学学报》2008年第5期973-976,共4页Chemical Journal of Chinese Universities

基　　金：国家“九七三”计划(批准号:2002CB211804)资助

摘　　要：运用电化学阻抗谱（EIS）、Raman光谱和XRD研究了石墨负极在1mol／L LiPF6-EC：DEC：DMC电解液中的电化学循环扫描过程．EIS研究结果表明，在电化学循环扫描4～10周范围内，SEI膜（固体电解质相界面膜）电阻随循环扫描周数增加近似线性增长，但石墨负极／电解液界面总阻抗由于电荷传递电阻的降低而减小．Raman光谱研究结果表明，在经历电化学循环扫描后，活性材料表层发生粉化和无定形化，石墨化程度降低；但XRD研究结果显示，石墨材料的本体结构没有发生变化，仍然保持着完整的石墨层状结构．The graphite anode during electrochemical scan cycles in 1 mol/L LiPF6-EC-DEC-DMC electrolyte solutions was investigated by EIS, Raman spectroscopy and XRD. It was found that the resistance of the SEI film increases almost linearly during the prolonged cycling in the 4-10 electrochemical scan cycles. However, the interface resistance between the graphite anode and the electrolyte solution decreases due to the decrease of the charge transfer resistance. After the electrochemical scan cycles, the active material on the surface of graphite anode is exfoliated and pulverized, and become amorphous, while the bulk of the active material remains unchanged.

关 键 词：石墨负极 电化学阻抗谱 拉曼光谱 X射线衍射 固体电解质相界面膜 

分 类 号：O646[理学—物理化学] TM912.2[理学—化学]