Suppressed Microcracking and F Penetration of Ni-Rich Layered Cathode via the Combined Effects of Titanium Dioxide Doping and Coating

To understand the effect of heat treatment of TiO2 modification for Ni-rich LiNi0.8Co0.1Mn0.1O2 cathode, the TiO2 coating layer is formed on the surface of LiNi0.8Co0.1Mn0.1O2 cathode by heat treatment at 500 and 600 degrees C. The electrochemical results show that TiO2-modified LiNi0.8Co0.1Mn0.1O2 shows higher electrochemical performances compared to pristine sample. Among them, the TiO2-modified LiNi0.8Co0.1Mn0.1O2 heat-treated at 500 degrees C delivers not only the highest initial discharge capacity of 201.3 mAh g(-1) but also the extraordinary rate capability (86.4% at 6.0C). Moreover, TiO2-modified LiNi0.8Co0.1Mn0.1O2 can effectively stabilize the cycling performance at 25 degrees C (79.4% after 100 cycles at 0.5C). Consequently, the TiO2-modified LiNi0.8Co0.1Mn0.1O2 by heat treatment at 500 degrees C can significantly improve the electrochemical performances due to facilitating Li-ion migration, working as a protective layer and inhibiting the irreversible phase transition.