Replica exchange molecular dynamics for Li-intercalation in graphite: a new solution for an old problem.

Autor: Park H; Centre for Material Science and Nanotechnology, Department of Chemistry, University of Oslo P.O. Box 1033, Blindern Oslo 0371 Norway heesoo.park@smn.uio.no alexey.koposov@kjemi.uio.no., Wragg DS; Centre for Material Science and Nanotechnology, Department of Chemistry, University of Oslo P.O. Box 1033, Blindern Oslo 0371 Norway heesoo.park@smn.uio.no alexey.koposov@kjemi.uio.no.; Department of Battery Technology, Institute for Energy Technology (IFE) Instituttveien 18, Kjeller 2027 Norway., Koposov AY; Centre for Material Science and Nanotechnology, Department of Chemistry, University of Oslo P.O. Box 1033, Blindern Oslo 0371 Norway heesoo.park@smn.uio.no alexey.koposov@kjemi.uio.no.; Department of Battery Technology, Institute for Energy Technology (IFE) Instituttveien 18, Kjeller 2027 Norway.
Jazyk: angličtina
Zdroj: Chemical science [Chem Sci] 2024 Jan 16; Vol. 15 (8), pp. 2745-2754. Date of Electronic Publication: 2024 Jan 16 (Print Publication: 2024).
DOI: 10.1039/d3sc06107h
Abstrakt: Li intercalation and graphite stacking have been extensively studied because of the importance of graphite in commercial Li-ion batteries. Despite this attention, there are still questions about the atomistic structures of the intermediate states that exist during lithiation, especially when phase dynamics cause a disordered Li distribution. The Li migration event (diffusion coefficient of 10 -5 nm 2 ns -1 ) makes it difficult to explore the various Li-intercalation configurations in conventional molecular dynamics (MD) simulations with an affordable simulation timescale. To overcome these limitations, we conducted a comprehensive study using replica-exchange molecular dynamics (REMD) in combination with the ReaxFF force field. This approach allowed us to study the behavior of Li-intercalated graphite from any starting arrangement of Li at any value of x in Li x C 6 . Our focus was on analyzing the energetic favorability differences between the relaxed structures. We rationalized the trends in formation energy on the basis of observed structural features, identifying three main structural features that cooperatively control Li rearrangement in graphite: Li distribution, graphite stacking mode and gallery height (graphene layer spacing). We also observed a tendency for clustering of Li, which could lead to dynamic local structures that approximate the staging models used to explain intercalation into graphite.
Competing Interests: The authors declare that they have no competing interests.
(This journal is © The Royal Society of Chemistry.)
Databáze: MEDLINE
Externí odkaz: