We have been studied the relation between electronic states, and cycle performances of LiMn2-xMxO4 (M = Mn, Mg, Al, Co, Ni, Zn) as cathode active materials for 4 V class Li secondary battery. The electronic density maps of the LiMn2-xMxO4 (M = Mn, Mg, Al, Co, Ni, Zn) shows the covalent bonding of Mn-O of LiMn2-xMxO4 (M = Mn, Mg, Al, Co, Ni, Zn) is stronger than that of LiMn2O4. On the other hands, we calculated that the net charge of each atom, the bond overlap population of Li-O, Mn-O, M-O, the density of states, and the electron density of LiMn1.75M0.25O4 (M = Mn, Mg, Al, Co, Ni, Zn) using first principles calculation by DV-Xα method. Li ionicity always keeps high and the covalent bonding of Mn-O in the octahedron of each LiMn1.75M0.25O4 is stronger than that of LiMn2O4.
抄録全体を表示