LiFePO4系列电池材料的电子结构与性能研究

用离散变分密度泛函(DFTDVM)方法计算了I-iMPO1(M=Mn，Fe、Co、Ni)和FePO1，讨论了组成、电子结构、化学键等与性能之间的关系。从LiMnPO，到LiNiPO1离子键和共价键强度都降低，再加上态密度的比较都表明，从LiMnPO1到LiNiPO1电导率逐渐升高。LiFePO1，的离子键和共价键强度都些FePO1低，以及态密度的变化都表明，LiFePO1，的电导率比FePO1高。O2P分态密度主要贡献总态密度靠近费米能级的价带，M3d主要贡献总态密度靠近费米能级的导带，其它各个分态密度的主峰则离费米能级较远。

Electronic Structure and Properties of Series Battery Material of LiFePO4

LiMPO_4 (M=Mn, Fe, Co and Ni) and FePO_4 are studied by density function and discrete variation (DFT-DVM) method. The correlation among composition, electronic structure, chemical bond and property have been studied. The strengths of ionic and covalent bonds mainly decrease in LiMPO_(4 )from Mn to Ni, and the variations of density of state(DOS) show that the electronic conductivity should be increased from Mn to Ni. The ionic and covalent bonds of LiFePO_(4 ) are both weaker than those of FePO_4, and the variations of DOS also show that the electronic conductivity of LiFePO_4 should be larger than that of FePO_4.M_(3d) partial DOS mainly contributes to the lowest conduction band(LCB), O_(2p) mainly contributes to the highest valence band(HVB) near to the Fermi level, and other partial DOS' are further away from the Fermi level.