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Title: Operando X-ray diffraction analysis for a glyme-based Li-O{sub 2} battery

Abstract

We investigated the effect of the carbon species in the air (oxygen) electrode, electrolyte concentration, and humidity in the supplied O{sub 2} gas on the Li-O{sub 2} reactions by using the operando XRD analysis. Regarding carbon species, we found that the over-potentials in the galvanostatic discharge-charge process were suppressed when using the KB carbon in the air electrode. The results of operando XRD measurements revealed that the Li{sub 2}O{sub 2} formed on the KB had the smaller crystalline or more amorphous like structures, which could be one reason for faster reaction kinetics of Li{sub 2}O{sub 2} dissolution. The discharge-charge curves of the cells with different concentration of LiTFSI/(G4){sub n} electrolyte showed the slight difference but less differences in the Li{sub 2}O{sub 2} formation and dissolution behaviors. In addition to the nature of Li{sub 2}O{sub 2} products, reaction of Li-salts would also have ineligible effects. We also found that the higher humidity in oxygen produced more the LiOH and promoted the Li{sub 2}O{sub 2} dissolution, which indicate that the LiOH formation could affect the Li{sub 2}O{sub 2} morphologies or surface chemistries. Our present results demonstrated that the operando XRD measurement are useful for analyzing the reaction mechanism of Li-O{sub 2} battery.

Authors:
; ; ; ; ;  [1];  [2]
  1. Device-functional analysis department, NISSAN ARC Ltd., 1 Natsushima, Yokosuka Kanagawa, 237-0061 JAPAN (Japan)
  2. Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Koto, Sayo Hyogo, 679-5198 JAPAN (Japan)
Publication Date:
OSTI Identifier:
22608256
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1763; Journal Issue: 1; Conference: FMS2015: 2. international symposium on frontiers in materials science, Tokyo (Japan), 19-21 Nov 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AVAILABILITY; CONCENTRATION RATIO; DISSOLUTION; ELECTRODES; ELECTROLYTES; HUMIDITY; LITHIUM HYDROXIDES; LITHIUM OXIDES; OXYGEN; REACTION KINETICS; SALTS; SURFACES; X-RAY DIFFRACTION

Citation Formats

Yogi, C., Takao, N., Kubobuchi, K., Matsumoto, M., Mogi, M., E-mail: mogi@nissan-arc.co.jp, Imai, H., and Watanabe, T. Operando X-ray diffraction analysis for a glyme-based Li-O{sub 2} battery. United States: N. p., 2016. Web. doi:10.1063/1.4961359.
Yogi, C., Takao, N., Kubobuchi, K., Matsumoto, M., Mogi, M., E-mail: mogi@nissan-arc.co.jp, Imai, H., & Watanabe, T. Operando X-ray diffraction analysis for a glyme-based Li-O{sub 2} battery. United States. doi:10.1063/1.4961359.
Yogi, C., Takao, N., Kubobuchi, K., Matsumoto, M., Mogi, M., E-mail: mogi@nissan-arc.co.jp, Imai, H., and Watanabe, T. Fri . "Operando X-ray diffraction analysis for a glyme-based Li-O{sub 2} battery". United States. doi:10.1063/1.4961359.
@article{osti_22608256,
title = {Operando X-ray diffraction analysis for a glyme-based Li-O{sub 2} battery},
author = {Yogi, C. and Takao, N. and Kubobuchi, K. and Matsumoto, M. and Mogi, M., E-mail: mogi@nissan-arc.co.jp and Imai, H. and Watanabe, T.},
abstractNote = {We investigated the effect of the carbon species in the air (oxygen) electrode, electrolyte concentration, and humidity in the supplied O{sub 2} gas on the Li-O{sub 2} reactions by using the operando XRD analysis. Regarding carbon species, we found that the over-potentials in the galvanostatic discharge-charge process were suppressed when using the KB carbon in the air electrode. The results of operando XRD measurements revealed that the Li{sub 2}O{sub 2} formed on the KB had the smaller crystalline or more amorphous like structures, which could be one reason for faster reaction kinetics of Li{sub 2}O{sub 2} dissolution. The discharge-charge curves of the cells with different concentration of LiTFSI/(G4){sub n} electrolyte showed the slight difference but less differences in the Li{sub 2}O{sub 2} formation and dissolution behaviors. In addition to the nature of Li{sub 2}O{sub 2} products, reaction of Li-salts would also have ineligible effects. We also found that the higher humidity in oxygen produced more the LiOH and promoted the Li{sub 2}O{sub 2} dissolution, which indicate that the LiOH formation could affect the Li{sub 2}O{sub 2} morphologies or surface chemistries. Our present results demonstrated that the operando XRD measurement are useful for analyzing the reaction mechanism of Li-O{sub 2} battery.},
doi = {10.1063/1.4961359},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1763,
place = {United States},
year = {Fri Aug 26 00:00:00 EDT 2016},
month = {Fri Aug 26 00:00:00 EDT 2016}
}
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