Citation

Yang H, Guo C, Chen J, Naveed A, Yang J, NuLi Y, Wang J. Angew Chem. Int. Ed. Engl. 2019; 58(3): 791-795.

Affiliation

Shanghai Jiao Tong University, Department of Chemical Engineering, 800 Dongchuan Rd, 200240, Shanghai, CHINA.

Copyright

(Copyright © 2019, Wiley-VCH)

DOI

10.1002/anie.201811291

PMID

30426649

Abstract

Safety concern poses a significant challenge for the large-scale employment of lithium-sulfur batteries. Extreme flammable conventional electrolyte and dendritic lithium deposition cause severe safety issues. Herein, we report an intrinsic flame-retardant (IFR) electrolyte consisting of 1.1 M lithium bis(fluorosulfonyl)imide in a solvent mixture of flame-retardant triethyl phosphate and high flash point solvent 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl (1:3, v/v) for safe lithium-sulfur (Li-S) batteries. This electrolyte exhibits favorable flame-retardant property and high reversibility of lithium metal anode (Coulombic efficiency >99%). Importantly, this IFR electrolyte enables stable lithium plating/stripping behavior with micro-sized and dense-packing lithium deposition at high temperatures. When coupled with sulfurized pyrolyzed poly(acrylonitrile) cathode (sulfur content: 52.6 wt%), Li-S batteries deliver high composite capacity (840.1 mAh g-1) and high sulfur utilization of 95.6%. More advantages of this system are its enhanced energy conversion efficiency and energy density under high temperature operation.

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Language: en

Keywords

battery safety; flame-retardant electrolyte; high temperature; lithium; lithium-sulfur batteries