【摘要】 正极材料是目前制约锂离子电池发展的关键因素。钒酸钠因具有较高的理论比容量和合适的脱嵌锂电位有望作为锂离子电池的正极材料。本文采用了水热-固相两步法合成了分散均匀的NaV3O8纳米片材料。采用X射线衍射(XRD),扫描电子显微镜(SEM)对所制备材料的物相和形貌进行了表征。以商业化金属锂片作为负极,NaV3O8为正极,商业化LiPF6电解液(1mol/L,碳酸亚乙酯-碳酸二甲酯为溶剂,体积比为1∶1)组装了锂离子电池。通过循环伏安(CV)和恒流充放电测试研究了电池的电化学性能。结果表明,NaV3O8具有良好的可逆脱嵌锂能力。在300mA/g电流密度下50次循环仍无明显的容量衰减,体现了优秀的循环稳定性能。更多还原

【Abstract】 The development of rechargeable lithium battery( RLB) is greatly restricted by the cathode material.NaV3O8 has attracted more and more interest as new cathode materials for rechargeable lithium battery( RLB) due to their high specific capacity,ease of synthesis,low cost,and so on. In the current work,NaV3O8 nanoflakes were fabricated by a novel two- step approach. The phase and morphology of as- prepared NaV3O8 was characterized by X- ray diffraction( XRD) and scanning electron microscopy( SEM),respectively. RLB was constructed using NaV3O8 as cathode,commercial lithium metal as anode and 1 mol / L LiPF6 as electrolyte( Guangzhou Tinci,1 MLiPF6 in 1 ∶1,V / V,ethylene carbonate- dimethyl carbonate). Constant current charge- discharge and cyclic voltammetry test were employed to analyze the electrochemical performance of the cell. The results showed that NaV3O8 had good Li ion insertion /extraction reversibility. NaV3O8 exhibited no obvious capacity fading after 50 cycles at 300 mA / g,demonstrating good cycling stability.更多还原