(合肥工业大学 材料科学与工程学院，合肥 230009)
摘 要: 采用固相反应法制备Mg2+掺杂的锂离子电池正极材料LiNil/3Col/3Mnl/3O2，并将Mg2+最佳掺杂量为0.03(摩尔分数)的样品进行CuO复合。通过X射线衍射(XRD)、扫描电镜(SEM)和电池测试系统等手段对制备的LiNil/3Col/3Mnl/3O2样品的结构、形貌及电化学性能进行表征。结果表明：Mg2+掺杂没有改变LiNil/3Col/3Mnl/3O2的层状结构，Mg2+掺杂量为0.03的LiNil/3Col/3Mnl/3-0.03Mg0.03O2材料具有最好的电化学性能和循环性能，在0.2C倍率下，首次放电比容量达158.5 mA？h/g，10次循环后容量保持率为91.2%。添加CuO的LiNil/3Col/3Mnl/3-0.03Mg0.03O2的首次放电容量为167.4 mA？h/g，高电压下达到181.0 mA？h/g；循环10次后，放电比容量为159.4 mA？h/g，容量保持率为95.3%，改性后的放电比容量、循环性能及在高倍率和高电压下的性能均得到改善。
关键字: LiNil/3Col/3Mnl/3O2；正极材料；Mg2+掺杂；电化学性能；合成
（School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China）
Abstract:The electrode materials LiNi1/3Col/3Mnl/3O2 doped Mg2+ were synthesized by solid state reaction, the optimum sample LiNil/3Col/3Mnl/3-0.03Mg0.03O2 was mixed with CuO. The structure, morphology and electrochemical properties of the as-prepared materials were characterized by XRD, SEM and battery testing system. The results show that Mg2+ doping does not change the material layer structure, and the optimum sample is LiNil/3Col/3Mnl/3-0.03Mg0.03O2, which has the best electrochemical properties and cycle performance. The first discharge specific capacity of LiNil/3Col/3Mnl/3-0.03- Mg0.03O2 is 158.5 mA？h/g at 0.2C, and the conservation ratio of capacity is about 91.2% after 10 cycles. The first discharge capacity and cycle performance of the sample mixed with CuO improve obviously, which are 167.4 mA？h/g at 0.2C and maintain 95.3% after 10 cycles. The materials have good performances at high rate and high voltage.
Key words: LiNi1/3Co1/3Mn1/3O2; cathode material; Mg2+ doping; electrochemical properties; synthesis
