LiNi_(0.85-x)Co_xMn_(0.15)O_2电化学性能的第一性原理研究

First-Principles Investigation on Electrochemical Performance of LiNi_(0.85-x)Co_xMn_(0.15)O_2

采用基于密度泛函理论的第一性原理平面波赝势方法计算了空间群为R3m的层状LiNi_(0.85-x)Co_xMn_(0.15)O_2的带隙、分波态密度、嵌锂形成能和晶胞体积.结果表明,LiNi_(0.85-x)Co_xMn_(0.15)O_2具有较高的可逆容量,又具有较好的电池稳定性,为该系列金属氧化物中较理想的锂离子电池正极材料,计算结果与实验结果一致性较好.采用的CASTEP中原子混合改变镍、钴掺杂量后,分析了LiNi_(0.85-x)Co_xMn_(0.15)O_2的物理性质及电化学性质.揭示了镍钴掺杂量对锂离子电池正极材料性能的影响,进而为寻找新的三元正极材料提供理论指导.

Based on density functional theory of first-principle, band gap, partial density of states, energy of Lithium ion insertion and cell volume of layered structure LiNi0.85-xCoxMn0.15O2 with space group R3^-m are calculated. Calculation results show that LiNi0.85-xCoxMn0.15O2, which owns high reversible capacity and good performance, is perfect for cathode materials of lithium-ion batteries among the metal oxide. The calculation results match well with the experimental ones. The nickel and cobalt content change herein adopted Mixture Atom Editor of CASTEP program, and the physical and electrochemical property of LiNi0.85-xCoxMn0.15O2. This reveals the influence of nickel and cobalt content change performance of material for lithium ion battery, and then provides theoretical direction for searching new ternary cathode materials.