Catalytic Interfaces‐Enriched Hybrid Hollow Spheres Sulfur Host for Advanced Li–S Batteries

Abstract

AbstractLithium–sulfur (Li–S) batteries are considered as a promising next‐generation energy storage technology due to its high energy density over 2500 Wh kg−1 and low cost. Its development and application require to overcome several obstacles including the large volume change, the low electrical conductivity of S/Li2S, and the shuttle effect of lithium polysulfides (LIPSs). In this work, the hollow N‐doped carbon spheres (NHCS) decorated with nanosized SnS2 (NHCS‐SnS2) are synthesized and investigated to host sulfur used as the cathode for Li–S batteries. Highly conductive NHCS offer a large specific surface area and robust confinement for active material S, while SnS2 nanoparticles provide efficient chemisorption of LIPSs and promote the deposition of solid Li2S. The NHCS‐SnS2/S cathode materials deliver a high discharge capacity 1344 mAh g−1 at 0.2 C and a low capacity decay over 200 cycles at 0.5 C. The outstanding cycling stability at 0.2 C with high sulfur loading of 3.0–3.1 mg cm−2 can also be readily attained. The excellent electrochemical performance is attributed to possible triple phase catalytic effect of NHCS‐SnS2 and electrolyte, and such structure permits the full utilization of active materials from S8 to Li2S.