最小二乘法在精确测定o-LiMnO_2掺杂中的应用  

Application of Least Square Method in Precise Measurement of o-LiMnO_2 Doping

作　　者：郑宇亭 郝晓剑[2] 牛甲明 胡慧中[1] 潘保武[1,3] 

机构地区：[1]中北大学材料科学与工程学院,太原030051 [2]中北大学仪器与电子学院,太原030051 [3]国防科技重点实验室,太原030051

出　　处：《材料导报（纳米与新材料专辑）》2015年第2期186-190,共5页

基　　金：国家自然科学基金面上项目(61473267);国防技术基础科研基金(JSJC2013408C009)

摘　　要：正交层状锰酸锂(o-LiMnO2)是高能量密度锂离子电池关键正极材料之一,是当前的研究热点。掺杂改性是提高晶体结构稳定性,改善循环性能的有效方法之一。采用水热法分别进行了Cr、Y、Mg掺杂实验及掺杂分析,得出了最优掺杂条件。在此实验基础上,以正交晶系法式方程,利用最小二乘法精确测定了o-LiMnO2最优掺杂量(4%Cr、4%Y(原子分数))的晶格常数,验证了对主体晶格的影响,与理论相吻合。并且通过计算Mg的不同掺杂量引起的晶格常数变化逆向证明了该方法的可靠性,得出对于层状结构6%Mg(原子分数)为最优掺杂比例。Layered orthogonal LiMnO2, a hot spot in current research, is a key cathode material for the high energy density lithium ion battery. Doping modification is an effective way to improve the crystal structure stability and cycle performance. Hydrothermal method was used for Cr, Y, Mg doping respectively and the best synthesis con- dition was investigated. Based on the products, orthogonal crystal system normal equation and the least square method was used to accurately figure out the lattice constant of o-LiMnO2, the optimal doping amount （atomic ratio 4at% Cr or 4at%Y） and influence of doping to host lattice was confirmed, as well as the result was consistent with theory anal- ysis. Additionally, the difference of o-LiMnOe lattice constant which caused by Mg doping were reversely testified the reliability of this method, and 6at%Mg is the optimal Mg doping ratio for layered structure was investigated.

关 键 词：o-LiMnO2掺杂 最小二乘法 晶格计算 

分 类 号：TG115.23[金属学及工艺—物理冶金] TM910.1[金属学及工艺—金属学]