【摘要】 以碳酸盐为沉淀剂,采用共沉淀法合成晶型良好的亚微米级Li(Ni1/3Co1/3Mn1/3)O2粉末,并将其与AgNO3复合,采用无电流分解沉积法制备出了Ag表面修饰的Li(Ni1/3Co1/3Mn1/3)O2/Ag电极材料。利用X-射线衍射、扫描电镜及电化学测试等方法表征材料的结构、形貌和电化学性能。结果表明:Ag单质的存在可明显改善Li(Ni1/3Co1/3Mn1/3)O2的电化学性能,尤其是倍率特性,以0.2C、0.5C、1C倍率放电进行测试,经过40次循环后比容量分别为156.2、144.3、137.7mAh.g-1,其容量保持率分别为96.2%、95.3%、93.9%。Ag的表面修饰能使Li(Ni1/3Co1/3Mn1/3)O2电荷转移阻抗大幅度减小,阻抗从65Ω减小到50Ω。更多还原

【Abstract】 The sub-micron Li(Ni1/3Co1/3Mn1/3)O2 powders with high crystallinity were prepared by co-precipitation method using carbonate as the precipitant.Silver nitrate was employed in the preparation of Li(Ni1/3Co1/3Mn1/3)O2 /Ag composite by an electroless deposition method.The microstructure,morphology and electrochemical performance of the composite were characterized by X-ray diffractometry,scanning electron microscopy and electrochemical techniques.The results indicate that the presence of Ag is favorable to the electrochemical performances of Li(Ni1/3Co1/3Mn1/3)O2,particularly high rate performance.After 40 cycles at a discharge rate of 0.2C,0.5C and 1C,the discharge capacity is 156.20,144.29 and 137.68 mAh·g-1,respectively,which is corresponded to capacity retention of 96.2%,95.3% and 93.9%.The Ag coating on the surface of Li(Ni1/3Co1/3Mn1/3)O2 particle can decrease its charge transfer impedance from 65Ω to 50Ω.更多还原