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为了研究Mg ,Al掺杂对锂二次电池正极材料LiCoO2 体系的电子结构的影响 ,进而揭示Mg掺杂的LiCoO2 具有高电导率的机理 ,对Li(Co ,Al)O2 和Li(Co,Mg)O2 进行了基于密度泛函理论的第一原理研究 .通过对能带及态密度的分析 ,发现在Mg掺杂后价带出现电子态空穴 ,提高了电导 ,并且通过歧化效应 (disproportionation)改变了Co 3d电子在各能级的分布 ,而Al掺杂则没有这些作用 .O2 - 的离子性在掺杂后明显增强 .
In order to study the influence of Mg and Al doping on the electronic structure of LiCoO2 cathode system for lithium secondary battery, the mechanism of high conductivity of LiCoO2 doped with LiCoO2 was revealed. The effects of Li (Co, Al) O2 and Li (Co, Mg ) O2 has been used to study the first principle based on density functional theory.By analyzing the energy band and state density, it is found that valence electron states holes appear in the valence band after Mg doping, the conductance is improved, and by disproportionation, Which changed the distribution of Co 3d electrons at each energy level, whereas Al doping did not have these effects. The ionicity of O 2 - was obviously enhanced after doping.