Lithium-sulfur battery with lithium polysulfide catholyte

Zhang, Zhengcheng; Xue, Zheng; Zhao, Feng

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DOE OSTI · 1735277

Lithium-sulfur battery with lithium polysulfide catholyte

Zhang, Zhengcheng·Xue, Zheng·Zhao, Feng

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Abstract

A liquid catholyte for a Li-S battery comprises a non-aqueous solution of at least one lithium polysulfide of formula Li 2 S x (wherein x is selected from 4, 6, and 8) and an anion receptor compound capable of complexing with polysulfide anion. The non-aqueous solution typically is composed of the Li 2 S x and the anion receptor compound dissolved in a non-aqueous solvent (e.g., one or more organic ether or fluorinated ether solvents). The anion receptor compound typically is present in the catholyte at a concentration of about 0.1 M to about 4 M. Li-S batteries comprise a metallic lithium anode; a porous conductive substrate; a separator membrane between the anode and the porous conductive substrate; and the liquid catholyte composition within pores of the substrate.

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25 ENERGY STORAGE 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

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Zhang, Zhengcheng, Xue, Zheng, Zhao, Feng. 2020-09-15. Lithium-sulfur battery with lithium polysulfide catholyte. https://www.osti.gov/biblio/1735277

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