Enhanced Electrochemical Kinetics and Polysulfide Traps of Indium Nitride for Highly Stable Lithium-Sulfur Batteries

摘要

Lithium-sulfur (Li-S) batteries are strongly considered as promising energy storage devices due to their high capacity and large theoretical energy density. However, the shuttle of polysulfides and their sluggish kinetic conversion in electrochemical processes seriously reduce the utilization of active sulfur, leading to a rapid capacity fading. Herein we introduced indium nitride (InN) nanowires into Li-S batteries through separator modification. Both the indium cation and electron-rich nitrogen atom of InN served as the polysulfide traps through strong chemical affinity. Meanwhile, the rapid electron transfer on the surface of InN accelerated the conversion of polysulfides in a working battery. The bifunction of InN nanowires effectively suppressed the shuttle effect. Therefore, Li-S batteries with InN-modified separators exhibit excellent rate performance and high stable cycling life with only 0.015% capacity decay per cycle after 1000 cycles, which affords fresh insights into the energy chemistry of high-stable Li-S batteries.