Hexagonal boron nitride effect on the performance of graphene-based lithium-sulfur batteries and its stability at elevated temperatures

Lithium-sulfur (Li-5) batteries based on a conversion mechanism hold great promise for next-generation batteries. But a limitation of this technology is the rapid capacity fading resulting from the generation of long-chain lithium polysulfides (Li2Sx), a phenomenon called shuttle effect and the insulating nature of sulfur. To this extent, 2D graphene and its derivatives have been widely investigated to overcome Li-S batteries' drawbacks owing to their outstanding properties. However, the restacking of graphene makes it impossible to obtain the benefits of 2D graphene fully. Thus, the integration of 2D graphene with other 2D materials such as hexagonal boron nitride (h-BN), suggests a rational option to avoid this problem. In this work, we found that the addition of h-BN to reduced graphene oxide (RGO) resulted in a 2.5 times increase in the electrochemical performance of graphene-based Li-S batteries. Likewise, RGO/h-BN/S composites also showed stable performance at elevated temperatures of similar to 100 degrees C.

Automated summary

Lithium-sulfur batteries based on a conversion mechanism show great potential but suffer from rapid capacity fading, shuttle effect, and the insulating nature of sulfur. Integrating graphene with other 2D materials like h-BN can significantly enhance the electrochemical performance of Li-S batteries.