Review of Cathode in Advanced Li−S Batteries: The Effect of Doping Atoms at Micro Levels

Abstract

AbstractIn recent years, the atom‐doping strategy has attracted extensive attention in lithium‐sulfur batteries. The reasonable structure design and introduction of doping atoms into sulfur cathode materials not only improve the utilization rate of active materials but also catalyze the redox kinetics of polysulfides, which greatly improves the electrochemical performance of the lithium‐sulfur batteries. However, the understanding of the functional mechanism and conversion mechanism of the doping atoms at micro levels is still limited. Hence, it is very crucial to explore the influence of doping atoms on the electronic arrangement and electrochemical active sites. Herein, the development of atomic doping in lithium‐sulfur batteries is reviewed, and the structure‐activity relationship between doped atoms and the adsorption of lithium polysulfide is analyzed. Furthermore, the catalytic mechanisms of catalytic materials were unmasked from microscopic perspectives, namely ion transport, surface electronic structure, energy band structure and state density.