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.
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)
关键词
o-LiMnO2掺杂
最小二乘法
晶格计算
orthogonal LiMn（）2, doping, least square equation method, crystal lattice calculation
