不同方法对合成P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_2的影响

Effect of P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_2 synthesized by different methods

采用固相法、醋酸盐燃烧法、氢氧化物共沉淀、草酸盐共沉淀的方法制备P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_2钠离子电池层状正极材料。通过X射线衍射分析(XRD)、扫描电子显微镜(SEM)和电化学手段等不同测试方法,对比不同方法对合成材料结构、形貌及电化学性能的影响。实验结果表明,用氢氧化物共沉淀法结合固相反应所制备的正极材料具有更优的电化学性能。该材料在0.1 C倍率,2.0~4.0 V电压范围下首次放电比容量为87.9 m Ah/g。1.0 C首次放电比容量为72.3 m Ah/g,50次循环后的容量保持率为108.0%。

P2-Na2/3Ni1/3Mn2/3O2 has been prepared by solid state method, acetate combustion method, hydroxide co-precipitation method and oxalate co-precipitation method, respectively. XRD,SEM,electrochemical testing are employed to characterize the influence on structure, morphology and electrochemical performance of the materials.Results show that the best electrochemical performance is achieved for the sample synthesized with a hydroxide co-precipitation method followed by solid state reaction. The material can deliver an initial discharge capacity of87.9 mAh/g at 0.1 C. It also can provide the initial discharge capacity of 72.3 mAh/g and maintain 108.0% of its initial capacity after 50 cycles between 2.0 and 4.0 V.