Li2S@NC composite enable high active material loading and high Li2S utilization for all-solid-state lithium sulfur batteries

All-solid-state Li–S batteries (ASSLSBs) offer an opportunity to realize both high energy density , safety and reliability, via eliminating the polysulfides shuttle effect and flammable liquid electrolyte. However, the sluggish kinetics of S and Li 2 S solid conversion results in low discharge capacity at high active material loading, which is critical for ASSLSBs to implement the high energy density potential. Herein, nitrogen doped-carbon (NC) coated Li 2 S (Li 2 S@NC composite) is developed for ASSLSBs that highly improves electrochemical performance. A thin and uniform nitrogen doped-carbon layer is coated on Li 2 S via pyrolysis deposition approach to prepare Li 2 S@NC. The as obtained Li 2 S@NC composite exhibits greatly enhanced electrochemical performance with high reversible capacity, high coulombic efficiency of ~100%, good rate capability and cycling stability. Particularly, outstanding electrochemical performance with high capacity of 931 mAh g −1 can also be obtained at both high Li 2 S content (43%) and high areal Li 2 S loading (10.4 mg cm −2 ).