Synchronous construction of oxygen vacancies with suitable concentrations and carbon coating on the surface of Li-rich layered oxide cathode materials by spray drying for Li-ion batteries

Lithium-rich layered oxide materials with high reversible capacities (over 250 mAh g(-1)) are considered as one of the most promising cathode materials for the next generation of lithium-ion batteries. How-ever, some challenges including low initial Coulombic efficiency, voltage decay and poor cycling restrict their commercial application. Herrin, Li-rich layered oxide materials Li1.2Ni0.2Co0.08Mn0.52O2 co-modified by constructing oxygen vacancies with suitable concentration and C coating layer have been synthesized via a facile spray drying process. The oxygen vacancies with suitable concentration can not only suppress the release of O-2 and improve the stability of the layered structure, but also facilitate Li diffusion. More -over, C coating layer acts as a physical barrier to protect the materials from electrolyte, and reduce the interface impedance. The co-modified material shows excellent electrochemical properties: a high initial Coulombic efficiency of 83.1%, a small voltage decay rate of 0.306 mV, and a capacity retention of 78.3% after 1000 cycles at 5 C. And it provides a simple and feasible way to improve the properties of lithium-rich layered oxide materials. (c) 2021 Elsevier Ltd. All rights reserved.