【摘要】 合成了一系列金属离子掺杂尖晶石 LiMn2-yMyO4（M=Al,Cr,Zn,Mg等）,并对其高温性能进行了测试分析。结果表明:金属离子掺杂使锰尖晶石材料的高温循环性能得到明显改善,但电化学比容量有所降低。掺杂材料中Mn3+含量有所降低,抑制了锰的溶解及 Jahn-Teller效应,削弱了锰尖晶石材料在充放电过程中相变的剧烈程度;Al、Cr、Ga的掺杂增强了[MO6]八面体的稳定性,有利于材料循环性能的改善。各种金属掺杂材料电化学比容量之间存在差异,材料的比容量一方面取决于掺杂金属离子在尖晶石结构中的价态,另一方面取决于掺杂离子所处的位置。更多还原

【Abstract】 Several metal-ion-substituted spinels LiMn2-yMyO4(M= Al, Cr, Zn, Mg, et al) were synthesized and tested at 55℃ as cathode materials for lithium-ion cells. The results showed that the substitution of metal-ion for Mn improved the cycling stability of the mangano-spinels, but reduced of the capacity. In the substituted materials, Mn3+ content was lowered, and therefore the manganese dissolution and Jahn-Teller effect were weakened, phase transition during cycling was lessened. Moreover, structural stability of [MO6] octahedra was enhanced by Al, Cr or Ga substitution.更多还原