Kinetic study of LiMn2O4 in process of lithium intercalation

Exchange current density of spinel LiMn2O4 was studied by linear polarization. The relationship of the kinetic property with the structure of spinel LiMn2O4 was investigated by studying the effect of the doping and surface coating on the kinetic properties of electrode material. The results show that the exchange current density of spinel LiMn2O4 electrode increases with the increase of the amount for lithium intercalation at first, and then decreases. The maximal exchange current density appeares at the 80%–90% lithium intercalation. The similar phenomenon was observed on the doped spinel LiMn2O4 electrode. Doping can enhance the exchange current density of spinel LiMn2O4 material. However, the degree of the doping effect varies with the doped element varying. Surface coating can also enhance the exchange current density of spinel material, and the increment of value is higher than that of doped ones.