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suffer from safety problems arising from lithium anode and fast capacity fading due to the insulating nature of sulfur, the dissolution-induced polysulfide shuttle reaction, and large volume changes. [4][5][6] To address these issues, carbonaceous material [7,8] and conducting polymers [9] have been used to trap the high-order polysulfides in the cathodes; protective layers and electrolyte additives are employed for protection of metallic-lithium anodes from reactions with polysulfide. [10,11] However, the shuttle reaction still exists, and the safety issue induced by lithium dendrite is still a great challenge.All-solid-state Li-S batteries can completely inhibit the dissolution of polysulfide, eliminate the polysulfide shuttle, and avoid lithium dendrite formation. [12][13][14][15][16][17][18][19] However, the use of rigid solid electrolytes in all-solid-state Li-S batteries also increases the stress/strain and interface resistance and reduce the reaction kinetics. [20][21][22] The key challenge is to minimize stress/strain and to construct a robust electronic and ionic pathway in the sulfur cathode, due to the electronic/ionic insulting nature of sulfur. For enhancing the electronic conductivity and reducing the electronic contact resistance, Kobayashi et al. synthesized a sulfur and acetylene black (AB) nanocomposite cathode using a gas-phase mixing method, and reported a reversible capacity of 900 mA h g −1 at a current density of 0.013 mA cm −2 in all-solid-state batteries. [23] The sulfur and carbon-nanofibers composite cathode also shows a high capacity in the all-solid-state Li-S batteries. [24] To ensure high ionic conduction in the sulfur cathode, Lin et al. synthesized core-shell structured lithium-sulfide nanoparticles with an Li 3 PS 4 electrolyte as shell, showing six orders of magnitude higher in ionic conductivity than that of bulk lithiumsulfide. Excellent cyclic performance was demonstrated for allsolid-state Li-S batteries at 60 °C. [13] By incorporation of five sulfur atoms in the Li 3 PS 4 electrolyte, the Li 3 PS 4+5 cathode with loading density of 0.25-0.6 mg cm −2 exhibits excellent cycling stability for all-solid-state Li-S batteries. [14] These studies demonstrate that a close contact of the nanosulfur, either to carbon or to electrolytes, and uniformly distributing these composites into an ionic/electronic conducting matrix, can significantly improve the electrochemical performances of solid-state Li-S cell because the nano-sulfur contacts both the highly ionic and Safety and the polysulfide shuttle reaction are two major challenges for liquid electrolyte lithium-sulfur (Li-S) batteries. Although use of solid-state electrolytes can overcome these two challenges, it also brings new challenges by increasing the interface resistance and stress/strain. In this work, the interface resistance and stress/strain of sulfur cathodes are significantly reduced by conformal coating ≈2 nm sulfur (S) onto reduced graphene oxide (rGO). An Li-S full cell consisting of an rGO@S-Li 10 GeP 2 S 12 -acetyle...