铬掺杂对硅酸铁锂电学性能影响的计算机仿真研究

Research on the Computer Simulation of the Effect of Cr Doping on the Electrical Properties of Li2FeSiO4

硅酸铁锂是一种锂离子电子的正极材料,由于其晶胞在理论上可允许可逆脱嵌两个锂原子,使得其理论比容量有巨大的提升空间,加上原料易得、无污染及成本低的优势,受到了人们的重视。正极材料掺杂被认为是改善其导电性能的有效途径。论文通过运用基于第一性原理方法的计算机仿真技术,对铬掺杂硅酸铁锂的结构和导电性能的影响进行了计算机仿真研究,结果表明未掺杂的硅酸铁锂其带隙快读为2.44eV,掺杂铬之后硅酸铁锂带隙减小为2.31eV,表明铬掺杂可提高硅酸铁锂的导电性能。

Li2FeSiO4 is a kind of cathode material for lithium-ion electron.Because its crystal cell can allow two lithium atoms to be removed reversibly in theory,its theoretical specific capacity has a huge space to improve.At the same time,this material has the advantages of easy access to raw materials,pollution-free and low cost,and has been paid attention to by people.The doping of cathode material is considered to be an effective way to improve its electrical conductivity.By using the computer simulation technology based on the first principle method,this paper studies the effect of the structure and electrical conductivity of Cr doped Li2FeSiO4.The results show that the band gap of undoped Li2FeSiO4 is 2.44eV,and the band gap of Cr doped Li2FeSiO4 is reduced to 2.31eV,indicating that Cr doping can improve the electrical conductivity of Li2FeSiO4.