双功能仿生膜修饰改性Li_4Ti_5O_(12)负极材料

Li_4Ti_5O_(12) Modification by Bifunctional Bionic Membrane as Anode Materials for Lithium-ion Batteries

采用简单有效的自聚合方法在Li_4Ti_5O_(12)颗粒表面包覆兼具离子导电和电子导电双重功效的聚多巴胺(PDA)/导电碳黑Super P(SP)复合包覆层,获得了电化学性能优异的锂离子电池负极材料.利用X射线粉末衍射(XRD)、扫面电子显微镜(SEM)、透射电子显微镜(TEM)、充放电循环曲线和循环伏安(CV)等方法对复合材料的形貌、结构以及电化学性能进行表征.结果表明,当PDA包覆层的厚度为10 nm、Super P的含量为3%(质量分数)时,得到的包覆材料展示了优异的电化学性能:0. 2C倍率下初始放电容量为175m A·h/g,循环150周后,可逆放电容量仍在160 m A·h/g以上.

Anode material with excellent electrochemical properties was obtained by coating the polydopamine(PDA)/Super P(SP)layer with the dual effect of both ionic conduction and electronic conduction on the surface of Li 4Ti 5O 12 particles.The morphology,structure and electrochemical properties of the composites were characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(SEM),transmission electron microscopy(TEM),charge-discharge cycle curves,and cyclic voltammetry(CV).The results showed that when the thickness of the coating layer was controlled at about 10 nm and the content of Super P was 3%(mass fraction),the sample displayed an outstanding electrochemical performance:the initial discharge capacity is 175 mA·h/g at 0.2C and the reversible discharge capacity is still above 160 mA·h/g after 150 cycles.