Synthesis and Electrochemical properties of Li[Ni0.4Co0.2Mn(0.4-x)Mgx]O2-yFy via a Carbonate Coprecipitation

Abstract

Magnesium doped transition metal layered compounds, Li[Ni0.4Co0.2Mn(0.4-x)Mgx]O2-yFy (x = 0, 0.04, y = 0, 0.08) have been synthesized by a carbonate coprecipitation method. X-ry diffraction patterns revealed that this material has a typical layered structure with R3m space group. Spherical morphologies and mono-dispersed powders were observed by scanning electron microscopy. Mg and F substititions were effective for the improvement of physical properties. These improved physical characteristics enhanced the capacity retention, lower interfacial resistance, and thermal stability, even though the electrodes were cycled between 2.8 and 4.6 V.