LiMn_2O_4的高温比容量衰减研究

LiMn_2O_4 Special Capacity Attenuation in High Temperature

采用高温固相法合成了LiMn2 O4电极材料 ,运用电化学和阴极膜X射线衍射等方法研究了LiMn2 O4在高温 (≥ 50℃ )下 ,循环时比容量衰减的现象及其衰减机理。结果表明 ,温度越高 ,LiMn2 O4的自放电越严重 ;贮存时间越长 ,LiMn2 O4的可逆容量损失越大 ,平均放电电压越低 ;高温下LiMn2 O4中Mn的溶解是造成比容量衰减的重要原因。通过掺杂微量元素的方法能有效地改善尖晶石LiMn2

By high temperature solid phase methods we synthesized LiMn 2O 4 materials.LiMn 2O 4 special capacity fade phenomena and mechanics in high temperature are studied by galvano-chemistry and cathode film X-ray diffraction methods.The result shows that the self-discharge of LiMn 2O 4 increases with rising temperature;the longer the storage life, the greater the reversible special capacity loss of LiMn 2O 4, and the lower the average voltage.The Mn solution of LiMn 2O 4 in high temperature is the main reason that causes the special capacity fade By doping,the cycling properties of LiMn 2O 4 in high temperature can be effectively improved.