MgF_2包覆对正极材料LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2性能的影响  

Effect of MgF_2-coating on performance of LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2 cathode materials

作　　者：夏继平[1] 李晓云[1] 郭秋双 

机构地区：[1]中海油天津化工研究设计院,天津300131

出　　处：《无机盐工业》2016年第8期79-82,共4页Inorganic Chemicals Industry

摘　　要：通过浸渍法在正极材料LiNi1/3Co1/3Mn1/3O2的表面包覆MgF_2,通过XRD、SEM、交流阻抗（EIS）分析、充放电测试研究了不同量MgF2包覆对LiNi1/3Co1/3Mn1/3O2正极材料的结构与电化学性能的影响。结果表明,MgF2以非晶态形式包覆于LiNi1/3Co1/3Mn1/3O2材料颗粒的表面,当包覆量为3%（物质的量分数,下同）时,三元正极材料具有优良的电化学性能,在3.0-4.6 V充放电范围内0.1C充放电倍率下,首次放电比容量为196.3 mA·h/g,1C循环50次后容量保持率为95.7%,55℃高温下1C循环50次后容量保持率为93.3%。MgF2-coated LiNi1/3Co1/3Mn1/3O2 cathode materials were synthesized by impregnation method.The effects of amounts of MgF_2 coating on the structure,morphology,and electrochemical properties of LiNi1/3Co1/3Mn1/3O2 were analyzed by XRD,SEM,charge-discharge tests,and electrochemical impedance spectra（EIS）,respectively.Results showed that the uncrystalline MgF_2 uniformly distributed on the surface of the LiNi1/3Co1/3Mn1/3O2 particles.The sample with 3%（amount-of-substance fraction,same below） MgF2 coating showed excellent electrochemical properties.Between 3.0 -4.6 V,at 0.1C,the sample of above-mentioned exhibited a initial discharge capacity of 196.3 mA·h/g.At 1C,it maintained 95.7% of the initial capacity after 50 cycles,and 93.3% capacity retention after 50 cycles at 55 ℃.

关 键 词：锂离子电池 正极材料 LINI1/3CO1/3MN1/3O2 MGF2 包覆 

分 类 号：TQ131.11[化学工程—无机化工]