Abstract:

A co-precipitation route was utilized to synthesize the precursor of Ni_0.8Co_0.1Mn_0.1（OH）₂,which was mixed with MnCO₃ and Li₂CO₃ afterwards. After calcination in the oxygen atmosphere,Li₂MnO₃-LiNi_0.8Co_0.1Mn_0.1O₂ composite material was obtained.The structure,composition and morphology of the prepared materials were characterized by X-ray diffraction（XRD）,field emission scanning electron microscopy（FESEM） and transmission electron microscopy（TEM）,respectively.The electrochemical performance of the material was tested by galvanostatic charge/discharge measurements and electrochemical impedance spectroscopy.Results showed that the 3%（mass fraction） Li₂MnO₃ composite material exhibit higher initial discharge capability（183 mA·h/g at 0.5C）,more stable cycle performance（with capacity retention of 93.9% after 120 cycles）and better rate performance,compared with unmodified cathode.Thus,this strategy is extremely promising for the preparation of LiNi_0.8Co_0.1Mn_0.1O₂ electrode materials with enhanced electrochemical performances.

Key words: Li₂MnO₃, co-precipitation, nickel-rich material