In Situ‐Constructed LixMoS2 with Highly Exposed Interface Boosting High‐Loading and Long‐Life Cathode for All‐Solid‐State Li–S Batteries

Abstract

As the persistent concerns regarding sluggish reaction kinetics and insufficient conductivities of sulfur cathodes in all‐solid‐state Li–S batteries (ASSLSBs), numerous carbon additives and solid‐state electrolytes (SSEs) have been incorporated into the cathode to facilitate ion/electron pathways around sulfur. However, this has resulted in a reduced capacity and decomposition of SSEs. Therefore, it is worth exploring neotype sulfur hosts with electronic/ionic conductivity in the cathode. Herein, we present a hybrid cathode composed of few‐layered S/MoS2/C nanosheets (<5 layers) that exhibits high‐loading and long‐life performance without the need of additional carbon additives in advanced ASSLSBs. The multifunctional MoS2/C host exposes the abundant surface for intimate contacting sites, in situ‐formed LixMoS2 during discharging as mixed ion/electron conductive network improves the S/Li2S conversion, and contributes extra capacity for the part of active materials. With a high active material content (S + MoS2/C) of 60 wt% in the S/MoS2/C/Li6PS5Cl cathode composite (the carbon content is only ~3.97 wt%), the S/MoS2/C electrode delivers excellent electrochemical performance, with a high reversible discharge capacity of 980.3 mAh g−1 (588.2 mAh g−1 based on the whole cathode weight) after 100 cycles at 100 mA g−1. The stable cycling performance is observed over 3500 cycles with a Coulombic efficiency of 98.5% at 600 mA g−1, while a high areal capacity of 10.4 mAh cm−2 is achieved with active material loading of 12.8 mg cm−2.