Design of Size-Controlled Sulfur Nanoparticle Cathodes for Lithium-Sulfur Aviation Batteries

Lithium-sulfur (Li-S) battery has been considered as a strong contender for commercial aerospace battery, but the commercialization requires Ah-level pouch cells with both efficient discharge at high rates and ultra-high energy density. In this paper, the application of lithium-sulfur batteries for powering drones by using the cathode of highly dispersed sulfur nanoparticles with well-controlled particle sizes have been realized. The sulfur nanoparticles are prepared by a precipitation method in an eco-friendly and efficient way, and loaded on graphene oxide-cetyltrimethylammonium bromide by molecular grafting to realize a large-scale fabrication of sulfur-based cathodes with superior electrochemical performance. A button cell based on the cathode exhibits an excellent discharge capacity of 62.8 mAh cm(-2) at a high sulfur loading of 60 mg cm(-2) (i.e., 1046.7 mAh g(-1)). The assembled miniature pouch cell (PCmini) shows a discharge capacity of 130 mAh g(-1), while the formed Ah-level pouch cell (PCAh) achieves energy density of 307 Wh kg(-1) at 0.3C and 92 Wh kg(-1) at 4C. Especially, a four-axis propeller drone powered by the PC has successfully completed a long flight (>3 min) at high altitudes, demonstrating the practical applicability as aviation batteries.

Automated summary

This paper demonstrates the successful application of highly dispersed sulfur nanoparticles as the cathode material for lithium-sulfur batteries. The sulfur nanoparticles are efficiently prepared using an eco-friendly precipitation method and loaded on graphene oxide-cetyltrimethylammonium bromide through molecular grafting. The resulting cathodes exhibit superior electrochemical performance and have been used to power a four-axis propeller drone for a long flight at high altitudes, demonstrating the practical applicability as aviation batteries.