No abstract

Lithium−sulfur (Li−S) batteries have shown great potential in the nextgeneration energy storage devices due to high theoretical energy density and low cost. To obtain high-performance Li−S batteries, it is important to inhibit the polysulfide shuttle effect and improve the reaction kinetics of polysulfides. Herein, CoP nanoparticles coated by metal−organic framework-derived N-doped mesoporous carbon (CoP@N-C) composites are synthesized and applied in both a cathode for a sulfur host and a modified layer on a separator for high-energy-density Li−S batteries since the CoP component has strong chemical anchoring capability toward soluble polysulfides and high electrochemical activity toward polysulfides transformation. Meanwhile, the porous structure of conductive N-doped mesoporous carbon can not only buffer the volume variation of sulfur during the charge/discharge process but also enhance the charge transport rate in the cathode. The constructed batteries have demonstrated a high specific capacity of 1222 mAh g −1 (8.6 mAh cm −2 ) with a high sulfur areal loading of ∼7.0 mg cm −2 on cathodes, and a mass loading of 0.35 mg cm −2 for modified layer on separators. Its average capacity decay is only 0.076% per cycle after 100 cycles. This work presents the highly competitive performance of Li−S batteries on the areal capacity and capacity decay.

No abstract