Poor Stability of Li2 CO3 in the Solid Electrolyte Interphase of a Lithium-Metal Anode Revealed by Cryo-Electron Microscopy

© 2021 Wiley-VCH GmbH.

Détails bibliographiques
Publié dans:Advanced materials (Deerfield Beach, Fla.). - 1998. - 33(2021), 22 vom: 11. Juni, Seite e2100404
Auteur principal: Han, Bing (Auteur)
Autres auteurs: Zhang, Zhen, Zou, Yucheng, Xu, Kang, Xu, Guiyin, Wang, Hong, Meng, Hong, Deng, Yonghong, Li, Ju, Gu, Meng
Format: Article en ligne
Langue:English
Publié: 2021
Accès à la collection:Advanced materials (Deerfield Beach, Fla.)
Sujets:Journal Article Li-metal anodes Li-metal batteries cycling stability low-dose imaging solid electrolyte interphase
Description
Résumé:© 2021 Wiley-VCH GmbH.
The solid electrolyte interphase (SEI) dictates the cycling stability of lithium-metal batteries. Here, direct atomic imaging of the SEI's phase components and their spatial arrangement is achieved, using ultralow-dosage cryogenic transmission electron microscopy. The results show that, surprisingly, a lot of the deposited Li metal has amorphous atomic structure, likely due to carbon and oxygen impurities, and that crystalline lithium carbonate is not stable and readily decomposes when contacting the lithium metal. Lithium carbonate distributed in the outer SEI also continuously reacts with the electrolyte to produce gas, resulting in a dynamically evolving and porous SEI. Sulfur-containing additives cause the SEI to preferentially generate Li2 SO4 and overlithiated lithium sulfate and lithium oxide, which encapsulate lithium carbonate in the middle, limiting SEI thickening and enhancing battery life by a factor of ten. The spatial mapping of the SEI gradient amorphous (polymeric → inorganic → metallic) and crystalline phase components provides guidance for designing electrolyte additives
Description:Date Revised 01.06.2021
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.202100404