摘要
利用微波加热技术合成稀土掺杂基锂离子电池正极材料LiMn2-xRExO4(RE=Y,Nd,Gd,Ce),通过XRD、循环伏安及恒电流充放电测试研究了稀土掺杂离子对合成正极材料结构及电化学性能的影响。XRD测试结果表明,合适的掺杂量可以起到扩展锂离子脱嵌通道和稳定骨架结构的作用,稀土离子的引入可以部分取代原有的三价锰离子,由于稀土离子的离子半径较三价锰离子大,因此稀土掺杂锰酸锂材料的晶胞参数比未掺杂材料大,在一定程度上扩充了锂离子迁移的三维通道,更有利于锂离子的嵌入与脱嵌;循环伏安及恒电流充放电测试结果表明稀土掺杂有效提高了LiMn2O4材料的电化学循环可逆性及循环稳定性。
Rare earth elements dopant for LiMn2O4 materials and both LiMxM n2-xO4 (M=Y, Nd, Gd, Ce) and LiMn2O4 spinels were synthesized by microwave heading method. The doping effect of rare earth elements on structure and the electrochemical performances of the samples were investigated by XRD, cyclic vo ltammetry and charge-discharge tests. XRD test shows that the rare earths ions can partially replace Mn3+ in the spinel and because the radius of rare earths ions is bigger than that of Mn3+, samples doped with rare earth el ements have larger lattice constant comparing with that of undoped sample. Dodin g enables Li ion to transport more freely in the three dimensional pathway. Elec tr ochemical performances indicate that all samples doped with rare earth elements show good cycle stability.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2003年第4期413-416,共4页
Journal of the Chinese Society of Rare Earths
基金
河南省自然科学基金资助项目(004032700)
