1
Return

Graded Solvation-Structure Electrolyte for Synergistic Polysulfide Confinement and Interfacial Stabilization in Potassium-Sulfur Batteries

delete2026-07-07
delete0
delete
OA
AI
Z
Zhifei Mao
K
Keliang Wang *
B
Bahareh Tajvidi Safa
R
Ruiguo Yang
L
Li Xie
R
Ruigang Wang
DOI:10.1002/cey2.70279delete
deleteOriginal
deleteShare
deleteSave
View PDF
Abstract

Abstract

En 中文
Potassium-sulfur (K-S) batteries are promising candidates for high-energy-density and cost-effective energy storage system, yet their practical deployment is hindered by poor cycling stability arising from severe potassium polysulfides (KPSs) shuttle effect and interfacial instability. Herein, we report a moderately solvating electrolyte (MSE) based on graded electrolyte design strategy to achieve an optimal balance between KPSs confinement, K-metal stabilization, and redox kinetics. By leveraging the high polarity of tetraethylene glycol dimethyl ether, we ensure efficient salt dissociation and rapid KPSs redox kinetics, while a 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether-rich outer solvation environment reinforces interfacial integrity and suppresses parasitic reactions. This graded solvation-structure engineering facilitates a homogeneous K plating/stripping and promotes the formation of an inorganic-rich, mechanically robust solid electrolyte interface. Consequently, the MSE facilitates stable K─S redox chemistry, delivering excellent cycling stability over 1000 cycles at 0.5 A g−1. Furthermore, X-ray photoelectron spectroscopy and in-situ Raman spectroscopy analyses reveal that the reversible cleavage and reformation of C–S and S–S bonds within sulfurized polyacrylonitrile enable highly reversible K–S redox chemistry. This work provides new insights into electrolyte engineering for high-performance K-S batteries and offers a viable pathway toward safe and durable K-based energy storage systems.
Keywords:
graded solvation structure
interfacial stability
moderately solvating electrolyte
potassium-metal anode
potassium-sulfur batteries
AI Summary

AI Summary

Key information extracted from the uploaded paper, including a brief overview, abstract, background, key highlights, visual analysis, and future outlook.

Journal

Carbon Energy cover
Carbon Energy
IF:
24.2
Papers:
925
Citations:
8.9K

Organization

S
southwest jiaotong university
Scholars:
7.6K
Papers: 2.7K
Citations: 0
M
michigan state university
Scholars:
3.5W
Papers: 3.1W
Citations: 44
Cited Papers

Cited Papers

Citing Papers

Citing Papers