Improved electrochemical properties of nickel rich LiNi0.6Co0.2Mn0.2O2 cathode materials by Al2O3 coating

Al2O3 has successfully coated on LiNi0.6Co0.2Mn0.2O2 cathode material by a facile coating method. The results of scanning electron microscopy and transmission electron microscope images show that Al2O3 were successfully attached onto the surface of LiNi0.6Co0.2Mn0.2O2 as expected. Charge–discharge tests show that the Al2O3 coating LiNi0.6Co0.2Mn0.2O2 exhibits excellent electrochemical performance with a high initial discharge capacity of 180.2 mAh g-1 at 0.1 C and a high capacity retention of 95.2% after 100 cycles at room temperature under 1C. The superior performance of surface-modified LiNi0.6Co0.2Mn0.2O2 attributed to the uniform Al2O3 coating layer is expected to directly reduce the contact between the active cathode particles and electrolyte. Simultaneously, the uniform Al2O3 coating layer also improves structure stability and suppresses generation of oxygen.