Abstract: LiNi0.8Co0. 1Mn0.1O2 cathode was modified by Al2O3 coating via atomic layer deposition. Al2O3 coating layer prevents the reaction of the electrode with HF generated in the electrolyte, as well as metal dissolution, resulting in improving cycling stability. Nevertheless, too thick Al2O3 coating layer hinders the Li+ and electron conduction, resulting in poor rate performance. Four cycle Al2O3-coated LiNi0.8Co0.1Mn0.1O2 samples achieve a balance between the inhibition of interface side reaction and the kinetics of interface transport, resulting in best cycle stability and rate performance. Four cycle Al2O3- coated LiNi0.8Co0.1Mn0.1O2 cathode material can deliver an 60th discharge capacity of 163.6 mAh/g at 1C, and a superior discharge capacity of 162.6 mAh/g at 10C. The performance of electrode materials was maximized by the precise control of the coating thickness..
Key words: LiNi0.8Co0.1Mn0.1O2 ; atomic layer deposition; Al2O3 ; coating; cycling stability; rate performance