摘要

High-powered, LiAlO2 homogeneously coated LiNi0.90Co0.07Al0.03O2 (ACLNCAO) has been successfully synthesized by using a novel technique. A new design of Al(OH)(3) precipitation is applied via CO2 decomposition of NaAl(OH)(4) solution, a classical method has been used in aluminium oxide metallurgy, which enables to plant Al(OH)(3) on Ni0.928Co0.072 (OH)(2) precursors uniformly and efficiently. Experimental results from structure, morphology and composition analysis technologies demonstrate that an Al(OH)(3) layer is uniformly coated on the nickel-cobalt hydroxide precursor, and a gamma-LiAlO2 shell coated on the Ni-based cathode material. The Lithorn storage properties of as-prepared samples are characterized by electrochemical tests, transmission electron microscope (TEM) differential scanning calorimetry (DSC) and metallic nail penetration tests. The gamma-LiAlO2 modified material displays a high discharge capacity of similar to 224 mAh g(-1) at 0.2C and 205.8 mAh g(-1) at 1C rate at 25 degrees C and shows good capacity retention of 93.4% after 100 cycles, which is better than Al homogeneously doped LiNi0.90Co0.07Al0.03O2 (HLNCAO). Furthermore, ACLNCAO shows an upgraded thermal stability, which benefit from the LiAlO2 based surface prevent the high powered core from being attacked by electrolyte under high voltage state.