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Title: Visualizaing Li Deposition in Solvate Electrolytes.

Abstract

Abstract not provided.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1376796
Report Number(s):
SAND2016-8026C
646708
DOE Contract Number:
AC04-94AL85000
Resource Type:
Conference
Resource Relation:
Conference: Proposed for presentation at the 2016 New Mexico Regional Energy Storage and Grid Integration Workshop held August 23-24, 2016 in Albuquerque, NM.
Country of Publication:
United States
Language:
English

Citation Formats

Jungjohann, Katherine Leigh, Harrison, Katharine Lee, Leenheer, Andrew Jay, Hahn, Nathan, Meng, Xiangbo, Elam, Jeffery, Zhang, Ji-Guang, and Zavadil, Kevin R. Visualizaing Li Deposition in Solvate Electrolytes.. United States: N. p., 2016. Web.
Jungjohann, Katherine Leigh, Harrison, Katharine Lee, Leenheer, Andrew Jay, Hahn, Nathan, Meng, Xiangbo, Elam, Jeffery, Zhang, Ji-Guang, & Zavadil, Kevin R. Visualizaing Li Deposition in Solvate Electrolytes.. United States.
Jungjohann, Katherine Leigh, Harrison, Katharine Lee, Leenheer, Andrew Jay, Hahn, Nathan, Meng, Xiangbo, Elam, Jeffery, Zhang, Ji-Guang, and Zavadil, Kevin R. Mon . "Visualizaing Li Deposition in Solvate Electrolytes.". United States. doi:. https://www.osti.gov/servlets/purl/1376796.
@article{osti_1376796,
title = {Visualizaing Li Deposition in Solvate Electrolytes.},
author = {Jungjohann, Katherine Leigh and Harrison, Katharine Lee and Leenheer, Andrew Jay and Hahn, Nathan and Meng, Xiangbo and Elam, Jeffery and Zhang, Ji-Guang and Zavadil, Kevin R.},
abstractNote = {Abstract not provided.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Aug 01 00:00:00 EDT 2016},
month = {Mon Aug 01 00:00:00 EDT 2016}
}

Conference:
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  • We evaluate hydrofluoroether (HFE) cosolvents with varying degrees of fluorination in the acetonitrile-based solvate electrolyte to determine the effect of the HFE structure on the electrochemical performance of the Li-S battery. Solvates or sparingly solvating electrolytes are an interesting electrolyte choice for the Li-S battery due to their low polysulfide solubility. The solvate electrolyte with a stoichiometric ratio of LiTFSI salt in acetonitrile, (MeCN)(2)-LiTFSI, exhibits limited polysulfide solubility due to the high concentration of LiTFSI. We demonstrate that the addition of highly fluorinated HFEs to the solvate yields better capacity retention compared to that of less fluorinated HFE cosolvents. Ramanmore » and NMR spectroscopy coupled with ab initio molecular dynamics simulations show that HFEs exhibiting a higher degree of fluorination coordinate to Li+ at the expense of MeCN coordination, resulting in higher free MeCN content in solution. However, the polysulfide solubility remains low, and no crossover of polysulfides from the S cathode to the Li anode is observed.« less
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