CuO-coated Li[Ni0.5Co0.2Mn0.3]O2 cathode material with improved cycling performance at high rates

CuO was used to modify the surface of Li[Ni0.5Co0.2Mn0.3]O2 cathode material. The structure and electrochemical properties of the CuO-coated Li[Ni0.5Co0.2Mn0.3]O2 were investigated using X-ray diffraction, scanning electron microscope, and charge/discharge tests. The results showed that the CuO coated Li[Ni0.5Co0.2Mn0.3]O2 cathode exhibited an improved rate capability at room and elevated temperature at high rates. The 2.0 wt.% CuO coated sample had the capacity retention of higher than 89%, and high capacity of 179.7 mAh g−1 at 5C, in comparison with the capacity retention of 60% and capacity of 161.5 mAh g−1 for the pristine one at elevated temperature. The cyclic voltammograms and impedance spectra results revealed that the CuO coating reduced the polarization and improved the electrochemical activity of cathode. Thus the CuO-coated Li[Ni0.5Co0.2Mn0.3]O2 shows a potential lithium ion batteries for high power applications.

Graphical abstractDischarge capacity of pristine and 2.0 wt.% CuO-coated Li[Ni0.5Co0.2Mn0.3]O2 cells at a rate of 5C between 3.0 and 4.6 V at 60 °C.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► CuO was coated uniformly onto the surface of Li[Ni0.5Co0.2Mn0.3]O2 particles. ► The 2.0 wt.% CuO coated sample exhibits higher rate capacity and superior cycle performance at elevated temperature. ► The CV and EIS results revealed that CuO coating reduced the polarization and improved the electrochemical activity of cathode.