Effects of Complexant Concentration in Base Solution on the Structure and Electrochemical Properties of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2

摘要

LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 powders were synthesized from co-precipitated spherical metal hydroxide, Ni_(0.8)Mn_(0.1)Co_(0.1)(OH)_2. The effects of the complexant (NH_4OH) concentration in base solution on the microstructure, crystalline structure and electrochemical properties of the product were studied. The results of scanning electron microscopy showed that the particle morphology was more regular and the particle size tended to increase with improving the concentration of NH_4OH. The as-prepared material had a good a-NaFeO_2 hexagonal lamellar structure, as confirmed by X-ray diffraction pattern, the sample had the least Li~+/Ni~(2+) cation disorder when the concentration of NH_4OH was 1.5M, which contributing to good cycle performance, its initial discharge capacity achieved 198.5 mAh g~(-1) and the capacity retention rate was 95% after 50 cycles at 0.2C between 2.8 and 4.3V.