Al和Si等量共掺杂对LiMn_2O_4材料的电化学性能影响  

Effects of equimolar Al and Si co-doping on electrochemical properties of LiMn_2O_4 materials

作　　者：方俊杰 李莹 宋永慧 彭忠东 胡国荣 FANG Jun-jie;LI Ying;SONG Yong-hui;PENG Zhong-dong;HU Guo-rong(Hunan Province Geological Testing Research Institute,Changsha Hunan 410007,China;School of Metallurgy and Environment,Central South University,Changsha Hunan 410083,China)

机构地区：[1]湖南省地质测试研究院,湖南长沙410007 [2]中南大学冶金与环境学院,湖南长沙410083

出　　处：《电源技术》2018年第10期1441-1443,共3页Chinese Journal of Power Sources

摘　　要：用高温固相法合成了Al和Si等量共掺杂的尖晶石型LiMn_(2-2x)Al_xSi_xO_4 (x=0, 0.005, 0.010, 0.020)。通过X射线衍射(XRD)和扫描电镜(SEM)对样品进行表征,并对合成材料在常温(25℃)和高温(55℃)下的电化学性能进行研究。结果表明:合成的LiMn_(2-2x)Al_xSi_xO_4样品没有杂相;材料的首次充放电比容量随着掺杂量增加而降低,但循环性能得到了提高;Al^(3+)和Si^(4+)离子等量共掺杂可有效提高材料的循环性能,尤其是在高温条件下,当掺杂量x=0.010时,1 C循环50圈后容量保持率由未掺杂的87.29%提高到了91.57%。The spinel LiMn2-2xAlxSixO4(x=0,0.005,0.010,0.020)materials were successfully synthesized by high temperature solid phase method.The samples were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM)and their electrochemical performance were tested at room temperature(25℃)and elevated temperature(55℃).The results show that the synthesized LiMn2-2xAlxSixO4 sample has no heterogeneous phase.The first charge-discharge specific capacity of LiMn2O4 is decreased with the increase of the doping amounts,but the cycling performance is improved.The cycle performance of materials can be improved by the co-doping of Al3+and Si4+ions.Especially at elevated temperature,the capacity retention increases from 87.29%to 91.57%after 50 cycles at 1 C.

关 键 词：LIMN2O4 掺杂 循环性能 

分 类 号：TM912[电气工程—电力电子与电力传动]