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Title: Oxidized bacterial cellulose functionalized with SiO2 nanoparticles as a separator for lithium-metal and lithium–sulfur batteries
Award ID(s):
2103582 2129983
NSF-PAR ID:
10422722
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Cellulose
Volume:
30
Issue:
1
ISSN:
0969-0239
Page Range / eLocation ID:
481 to 493
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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  1. Abstract

    Despite the potential to become the next‐generation energy storage technology, practical lithium–sulfur (Li–S) batteries are still plagued by the poor cyclability of the lithium‐metal anode and sluggish conversion kinetics of S species. In this study, lithium tritelluride (LiTe3), synthesized with a simple one‐step process, is introduced as a novel electrolyte additive for Li–S batteries. LiTe3quickly reacts with lithium polysulfides and functions as a redox mediator to greatly improve the cathode kinetics and the utilization of active materials in the cathode. Moreover, the formation of a Li2TeS3/Li2Te‐enriched interphase layer on the anode surface enhances ionic transport and stabilizes Li deposition. By regulating the chemistry on both the anode and cathode sides, this additive enables a stable operation of anode‐free Li–S batteries with only 0.1 mconcentration in conventional ether‐based electrolytes. The cell with the LiTe3additive retains 71% of the initial capacity after 100 cycles, while the control cell retains only 23%. More importantly, with high utilization of Te, the additive enables significantly better cyclability of anode‐free pouch full‐cells under lean electrolyte conditions.

     
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