Enhanced electrochemical properties of Ni-rich LiNi0.8Co0.1Mn0.1O2 by SnO2 coating under high cutoff voltage

Extending the working voltage is an effective approach to enhance the reversible capacity of LiNi1-x-yCoxMnyO2 layered oxide cathode materials. However, the layered Ni-rich LiNi0.8Co0.1Mn0.1O2 cathode suffers a severe structural instability and rapid capacity decrease during high-voltage cycling (4.6 V). In order to solve these problems, the surface coating layer of SnO2 is successfully prepared via a one-step synthesis way followed with a high temperature calcination method. The 1.0% SnO2-modified LiNi0.8Co0.1Mn0.1O2 delivers a much higher capacity retention (83.63%) compared with pristine sample (71.58%) after 100 cycles at 1 C under 4.6 V. The coating properties of SnO2-coated LiNi0.8Co0.1Mn0.1O2 are probed via X-ray diffraction, scanning electron microscope, and transmission electron microscope. Our results provide a skillful approach to obtain the promising high performance of cathode materials with both high energy density and long calendar life to satisfy the growing demands of future lithium-ion battery.