Energy Storage Systems: Tracking the Influence of Thermal Expansion and Oxygen Vacancies on the Thermal Stability of Ni‐Rich Layered Cathode Materials (Adv. Sci. 12/2020)

Close relationship between Ni content and inherent thermal instability of Ni-rich cathode material has been widely investigated. However, the underlying cause of thermal instability of Ni-rich cathode material involving Ni has not been fully studied. In article number 1902413, Won-Sub Yoon and co-workers propose the thermal expansion and oxygen vacancy as critical factors to affect the inherent thermal instability of Ni-rich cathode materials. In the cover image, the thermal runaway of energy storage systems in industrial facilities is presented because it is closely related to the thermal instability of Ni-rich cathode materials.