Moradabadi, Ashkan ; Kaghazchi, Payam (2016)
Thermodynamics and kinetics of defects in Li2S.
In: Applied Physics Letters, 108 (21)
doi: 10.1063/1.4952434
Artikel, Bibliographie
Kurzbeschreibung (Abstract)
Li2S is the final product of lithiation of sulfur cathodes in lithium-sulfur (Li-S) batteries. In this work, we study formation and diffusion of defects in Li2S. It is found that for a wide range of voltages (referenced to metal Li) between 0.17 V and 2.01 V, positively charged interstitial Li (Li+) is the most favorable defect type with a fixed formation energy of 1.02 eV. The formation energy of negatively charged Li vacancy V(Li,-) is also constant, and it is only 0.13 eV higher than that of Li+. For a narrow range of voltages between 0.00 V and 0.17 V, the formation energy of neutral S vacancy is the lowest and it decreases with decreasing the cell voltage. The energy barrier for Li+ diffusion (0.45 eV), which takes place via an exchange mechanism, is 0.18 eV higher than that for V(Li,-) (0.27 eV), which takes place via a single vacancy hopping. Considering formation energies and diffusion barriers, we find that ionic conductivity in Li2S is due to both Li+ and V(Li,-), but the latter mechanism being slightly more favorable.
| Typ des Eintrags: | Artikel |
|---|---|
| Erschienen: | 2016 |
| Autor(en): | Moradabadi, Ashkan ; Kaghazchi, Payam |
| Art des Eintrags: | Bibliographie |
| Titel: | Thermodynamics and kinetics of defects in Li2S |
| Sprache: | Englisch |
| Publikationsjahr: | 26 Mai 2016 |
| Titel der Zeitschrift, Zeitung oder Schriftenreihe: | Applied Physics Letters |
| Jahrgang/Volume einer Zeitschrift: | 108 |
| (Heft-)Nummer: | 21 |
| DOI: | 10.1063/1.4952434 |
| Kurzbeschreibung (Abstract): | Li2S is the final product of lithiation of sulfur cathodes in lithium-sulfur (Li-S) batteries. In this work, we study formation and diffusion of defects in Li2S. It is found that for a wide range of voltages (referenced to metal Li) between 0.17 V and 2.01 V, positively charged interstitial Li (Li+) is the most favorable defect type with a fixed formation energy of 1.02 eV. The formation energy of negatively charged Li vacancy V(Li,-) is also constant, and it is only 0.13 eV higher than that of Li+. For a narrow range of voltages between 0.00 V and 0.17 V, the formation energy of neutral S vacancy is the lowest and it decreases with decreasing the cell voltage. The energy barrier for Li+ diffusion (0.45 eV), which takes place via an exchange mechanism, is 0.18 eV higher than that for V(Li,-) (0.27 eV), which takes place via a single vacancy hopping. Considering formation energies and diffusion barriers, we find that ionic conductivity in Li2S is due to both Li+ and V(Li,-), but the latter mechanism being slightly more favorable. |
| Fachbereich(e)/-gebiet(e): | 11 Fachbereich Material- und Geowissenschaften 11 Fachbereich Material- und Geowissenschaften > Materialwissenschaft 11 Fachbereich Material- und Geowissenschaften > Materialwissenschaft > Fachgebiet Materialmodellierung Zentrale Einrichtungen > Hochschulrechenzentrum (HRZ) > Hochleistungsrechner Zentrale Einrichtungen > Hochschulrechenzentrum (HRZ) Zentrale Einrichtungen |
| Hinterlegungsdatum: | 31 Mai 2016 07:29 |
| Letzte Änderung: | 26 Jul 2016 09:05 |
| PPN: | |
| Export: | |
| Suche nach Titel in: | TUfind oder in Google |
 |
Frage zum Eintrag |
Optionen (nur für Redakteure)
 |
Redaktionelle Details anzeigen |
Drucken
Impressum