稀土掺杂对LiMn_2O_4电化学性能的影响

Influence of doping rare-earth on electrochemical performanceof spinel LiMn_2O_4

用固相反应法合成了具有尖晶石结构的可用作锂离子二次电池正极材料的锂锰氧化合物（LiMn2O4）,并对其进行了镧、铈、镨、钕、铕、钐等多种稀土元素的掺杂修饰,形成稀土复合氧化物（LixMn2-yRe7y/6O4,0.95≤x≤1.2,0≤y≤0.3）。对材料进行了X射线衍射、循环伏安、充放电等测试,实验结果表明,掺入镧、铕、钕、钐、镨等元素所合成的材料具有标准尖晶石结构,较好的电化学可逆性能,较优良的高温性能。该材料在EC:DMC（1:1）+1mol/L LiPF6电解液中表现出了较优良的充放电性能,其首次放电容量达130mAh/g。

The spinel LiMn2O4 used as cathode materials for lithium-ion batteries was synthesized by solid state reaction process and modified by doping rare-earth such as La, Ce, Pr, Nd, Eu, Sm, etc. Testing of X-ray diffraction , cyclic voltammogram, charge-discharge and SEM were carried out for LiMn2O4 cathode materials and the modified materials. The results showed that the synthesized materials doped with La, Eu, Nd, Sm and Pr( LixMn2-yRe7y/6O4, 0.95≤x≤1.2, 0≤y≤0.3) exhibited standard spinel structure, high reversibility of electrochemistry and excellent properties of charge-discharge in EC: DMC(1 : 1) + 1mol/L LiPF6 electrolyte with first discharge capacity of 130mAh/g.