Using mixed solution of water and ethylene glycol as solvent,oxalic acid as complexing agent and precipitant,granule-like LiNi0.6Co0.2Mn0.2O2(NCM622) nanoparticles with a particle size of 300～500 nm was prepared by solvothermal method.Co3O4 coating with many mesopores was formed on the surface of the NCM622 particles by wet coating.The morphology and electrochemical properties (discharge performance,cycle performance,multiplier performance and material internal resistance) of the material were characterized by X-ray diffractometer,transmission electron microscope,constant-current charge-discharge technology,cyclic voltammetry(CV) and electrochemical impedance spectroscopy (EIS).The results shown that the electrode material coated by Co3O4 had some improvement in electrochemical performance.In particular,the material coated with 3% Co3O4 had the best electrochemical performance.At the 0.1C rate,the first discharge specific capacity reached 191mAh/g,and the cycle was maintained at 0.2C for 100 cycles.The capacity retention rate of the material increased from 61.2% to 87%,and the impedance after coating also decreased significantly.
Hou Jingjing, Wen Le, Zhao Shuning, Bei Fengli
. Preparation of Co3O4/LiNi0.6Co0.2Mn0.2O2 composite anode material with mesoporous coating[J]. New Chemical Materials, 2020
, 48(10)
: 78
-82
.
DOI: 10.19817/j.cnki.issn 1006-3536.2020.10.017
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