Investigation of Ni doped LiMn2O4 used as cathode materials for high voltage Lithium batteries

Abstract

Li-ion batteries are already used in many nomad applications, but improvement of this technology is still necessary to be durably introduced on new markets such as electric vehicle (EVs), hybrid electric vehicles (HEVs). Modification of the nature of the active electrode material is the most challenging and innovative aspect. Among high voltage spinel-oxides with general composition LiMxMn₂-xO₄ (M transition metals), Ni doped LiMn₂O₄, LiNi_xMn_2-xO₄ (0 < x < 0.7) possessing a potential voltage of ca. 4.7 V versus Li+/Li, is promising candidate for high power and high voltage lithium batteries. The materials were synthesized by solid state reaction of two annealing steps at 600°C and 900°C. The structure and electrochemical properties of these materials were characterized by XRD diffraction (XRD), Raman spectroscopy, Scanning electron microscopy (SEM), Cyclic Voltammetry (CV) and charge – discharge cycling test using Swagelok cell. It is demonstrated that LiNi_0.5Mn_1.5O₄ and LiNi_0.4Mn_1.6O₄ have remarkable properties such as high potential, high energy density, and good cycle life.