Microporous Carbon Nanoparticles for Lithium–Sulfur Batteries
Hui‐Ju Kang, Gazi A. K. M. Rafiqul Bari, Tae‐Gyu Lee, Tamal Tahsin Khan, Jae‐Woo Park, Hyun Jin Hwang, Sung Yong Cho, Young‐Si Jun
Abstract
Rechargeable lithium–sulfur batteries (LSBs) are emerging as some of the most promising next-generation battery alternatives to state-of-the-art lithium-ion batteries (LIBs) due to their high gravimetric energy density, being inexpensive, and having an abundance of elemental sulfur (S8). However, one main, well-known drawback of LSBs is the so-called polysulfide shuttling, where the polysulfide dissolves into organic electrolytes from sulfur host materials. Numerous studies have shown the ability of porous carbon as a sulfur host material. Porous carbon can significantly impede polysulfide shuttling and mitigate the insulating passivation layers, such as Li2S, owing to its intrinsic high electrical conductivity. This work suggests a scalable and straightforward one-step synthesis method to prepare a unique interconnected microporous and mesoporous carbon framework via salt templating with a eutectic mixture of LiI and KI at 800 °C in an inert atmosphere. The synthesis step used environmentally friendly water as a washing solvent to remove salt from the carbon–salt mixture. When employed as a sulfur host material, the electrode exhibited an excellent capacity of 780 mAh g−1 at 500 mA g−1 and a sulfur loading mass of 2 mg cm−2 with a minor capacity loss of 0.36% per cycle for 100 cycles. This synthesis method of a unique porous carbon structure could provide a new avenue for the development of an electrode with a high retention capacity and high accommodated sulfur for electrochemical energy storage applications.