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  • Competing Heat Carriers Leading to Distinctive Cation Concentration Dependent Thermal Conductivity of Amorphous Li x S ( x  = 0–2) Batteries
Title: Competing Heat Carriers Leading to Distinctive Cation Concentration Dependent Thermal Conductivity of Amorphous Li x S ( x  = 0–2) Batteries
Abstract Thermal transport in amorphous lithium‐sulfur (a‐LixS) is systematically investigated using molecular dynamics and the contributions from different types of heat carriers are quantitatively evaluated. In general, the thermal conductivity (TC) ofa‐LixS changes largely by varying the concentration (x) of Li ions ina‐LixS. Interestingly, the TC ofa‐LixS shows three distinct regimes of dependence on Li concentration. For low Li concentration (x = 0.4–1.2), the TC grows slowly, followed by a rapid increase in TC for medium Li concentration (x = 1.2–1.6), where the growth rate is three times that of the first regime, and finally, the TC is independent of Li concentration (x = 1.6–2.0). The TC enhancement in the first and second regimes is mainly attributed to propagating and non‐propagating vibrational modes ina‐LixS, respectively. In contrast, the stable thermal transport regime is governed by the competition between propagating and non‐propagating phonons. These investigations provide quantitative TC data of various polysulfides for shuttling analysis, and a fundamental understanding of the thermal transport mechanism of complexa‐LixS structures, which is beneficial for the rational design of thermal management of Li‐S batteries.  more » « less
Award ID(s):
2030128
PAR ID:
10419260
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Functional Materials
Volume:
33
Issue:
34
ISSN:
1616-301X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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