铝/石墨复合材料的制备及其电化学性能研究

Preparation and electrochemical property of Al/graphite composite material

铝作为负极材料其理论容量较高,但铝在充放电过程中会出现严重的体积膨胀,导致循环性能差。为克服铝体积膨胀严重的缺点,采用简单的球磨法成功制备出铝/石墨复合材料。利用X射线衍射仪、扫描电子显微镜对复合材料的结构和形貌进行分析。电化学性能测试表明,铝/石墨复合材料首次放电比容量高达1004mAh/g,循环15次后容量保持在300mAh/g。铝/石墨复合材料拥有较高的放电比容量和较好的循环性能,在锂离子电池负极材料中具有潜在的应用价值。

Al has the advantages of high specific capacity as cathode materials,but in the process of charging and discharging,the volume expansion of Al is too large,resulting in poor looping performance.Al/graphite composite materials were successfully prepared by ball milling,and then the phase structure and characterization of the morphology were analyzed by X-ray diffractometer(XRD)and electron microscope(SEM)respectively.The electrochemical measurements demonstrated that the composites had great improved electrochemical performances in comparison with pure Al.For example,the initial discharge capacity was 1004mAh/g,and can deliver the reversible capacity of 300mAh/g after 15th cycle.This suggested that the Al/graphite composite had a potential possibility to be developed as cathode materials for lithium-ion batteries.