Alleviating oxygen evolution from Li-excess oxide materials through theory-guided surface protection
Abstract
Li-excess cathodes comprise one of the most promising avenues for increasing the energy density of current Li-ion technology. However, the first-cycle surface oxygen release in these materials causes cation densification and structural reconstruction of the surface region, leading to encumbered ionic transport and increased impedance. In this work, we use the first principles Density Functional Theory to systematically screen for optimal cation dopants to improve oxygen-retention at the surface. The initial dopant set includes all transition metal, post-transition metal, and metalloid elements. Our screening identifies Os, Sb, Ru, Ir, or Ta as high-ranking dopants considering the combined criteria, and rationalization based on the electronic structure of the top candidates are presented. To validate the theoretical screening, a Ta-doped Li1.3Nb0.3Mn0.4O2 cathode was synthesized and shown to present initial improved electrochemical performance as well as significantly reduced oxygen evolution, as compared with the pristine, un-doped, system.
- Authors:
-
[2];
[4];
[7]
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Storage and Distributed Resources Division; Samsung Research America, Burlington, MA (United States). Advanced Materials Lab.
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Storage and Distributed Resources Division; Chinese Academy of Sciences (CAS), Guangdong (China). Inst. of High Energy Physics
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Storage and Distributed Resources Division; Toyota Research Inst., Los Altos, CA (United States)
- Univ. of California, Berkeley, CA (United States). Dept. of Chemical and Biomolecular Engineering
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Storage and Distributed Resources Division; Univ. of California, Berkeley, CA (United States). Dept. of Chemical and Biomolecular Engineering
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Storage and Distributed Resources Division
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Storage and Distributed Resources Division; Univ. of California, Berkeley, CA (United States). Dept. of Materials Science and Engineering
- Publication Date:
- Research Org.:
- Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- Sponsoring Org.:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
- OSTI Identifier:
- 1493271
- Grant/Contract Number:
- AC02-05CH11231; AC02-76SF00515
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Nature Communications
- Additional Journal Information:
- Journal Volume: 9; Journal Issue: 1; Journal ID: ISSN 2041-1723
- Publisher:
- Nature Publishing Group
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 25 ENERGY STORAGE
Citation Formats
Shin, Yongwoo, Kan, Wang Hay, Aykol, Muratahan, Papp, Joseph K., McCloskey, Bryan D., Chen, Guoying, and Persson, Kristin A. Alleviating oxygen evolution from Li-excess oxide materials through theory-guided surface protection. United States: N. p., 2018.
Web. doi:10.1038/s41467-018-07080-6.
Shin, Yongwoo, Kan, Wang Hay, Aykol, Muratahan, Papp, Joseph K., McCloskey, Bryan D., Chen, Guoying, & Persson, Kristin A. Alleviating oxygen evolution from Li-excess oxide materials through theory-guided surface protection. United States. https://doi.org/10.1038/s41467-018-07080-6
Shin, Yongwoo, Kan, Wang Hay, Aykol, Muratahan, Papp, Joseph K., McCloskey, Bryan D., Chen, Guoying, and Persson, Kristin A. Fri .
"Alleviating oxygen evolution from Li-excess oxide materials through theory-guided surface protection". United States. https://doi.org/10.1038/s41467-018-07080-6. https://www.osti.gov/servlets/purl/1493271.
@article{osti_1493271,
title = {Alleviating oxygen evolution from Li-excess oxide materials through theory-guided surface protection},
author = {Shin, Yongwoo and Kan, Wang Hay and Aykol, Muratahan and Papp, Joseph K. and McCloskey, Bryan D. and Chen, Guoying and Persson, Kristin A.},
abstractNote = {Li-excess cathodes comprise one of the most promising avenues for increasing the energy density of current Li-ion technology. However, the first-cycle surface oxygen release in these materials causes cation densification and structural reconstruction of the surface region, leading to encumbered ionic transport and increased impedance. In this work, we use the first principles Density Functional Theory to systematically screen for optimal cation dopants to improve oxygen-retention at the surface. The initial dopant set includes all transition metal, post-transition metal, and metalloid elements. Our screening identifies Os, Sb, Ru, Ir, or Ta as high-ranking dopants considering the combined criteria, and rationalization based on the electronic structure of the top candidates are presented. To validate the theoretical screening, a Ta-doped Li1.3Nb0.3Mn0.4O2 cathode was synthesized and shown to present initial improved electrochemical performance as well as significantly reduced oxygen evolution, as compared with the pristine, un-doped, system.},
doi = {10.1038/s41467-018-07080-6},
journal = {Nature Communications},
number = 1,
volume = 9,
place = {United States},
year = {Fri Nov 02 00:00:00 EDT 2018},
month = {Fri Nov 02 00:00:00 EDT 2018}
}
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Figures / Tables:
Figure 1: The dopant segregation energy as a function of dopant element for the 5 most stable low index surface facet in Li2MnO3. The circular charts are designed to give a visual overview of the surface segregation driving force by indicating red for bulk and blue for surface preference, respectively.more »
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