Interfacial Reactions in the Li/Si diffusion couples

Origin of Anisotropic Lithiation of Crystalline Si in Li-Si batteries

Yong Seok Choi, Jun Hyoung Park, Jae Pyoung Ahn, Jae-chul Lee

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

As opposed to the common understanding that diffusion into a cubic-structured single crystal is independent of its crystalline orientation, the diffusion of Li to crystalline Si (c-Si) is anisotropic, which acts as the major cause for the fracture of Si anodes in Li-ion batteries. Here, by conducting comprehensive/multi-scale simulation studies based on molecular dynamics and density functional theory, we elucidate how and why Li diffusion in c-Si is anisotropic. We found that Li ions diffuse to c-Si by following a particular atomic-scale space corresponding to the lowest value of the valence orbital in c-Si, causing Li ions to take a tortuous diffusion pathway. The degree of the tortuosity of the pathway differs depending on the crystallographic orientation of Si, and it acts as the major cause for anisotropic lithiation. We also develop a structural parameter that can quantitatively evaluate the orientation dependency of the lithiation of c-Si.

Original languageEnglish
Article number14028
JournalScientific Reports
Volume7
Issue number1
DOIs
Publication statusPublished - 2017 Dec 1

Fingerprint

electric batteries
ions
causes
anodes
molecular dynamics
density functional theory
valence
conduction
orbitals
single crystals
simulation

ASJC Scopus subject areas

  • General

Cite this

Interfacial Reactions in the Li/Si diffusion couples : Origin of Anisotropic Lithiation of Crystalline Si in Li-Si batteries. / Choi, Yong Seok; Park, Jun Hyoung; Ahn, Jae Pyoung; Lee, Jae-chul.

In: Scientific Reports, Vol. 7, No. 1, 14028, 01.12.2017.

Research output: Contribution to journalArticle

@article{53ff50a4604f4393aea7dabb472e4f6e,
title = "Interfacial Reactions in the Li/Si diffusion couples: Origin of Anisotropic Lithiation of Crystalline Si in Li-Si batteries",
abstract = "As opposed to the common understanding that diffusion into a cubic-structured single crystal is independent of its crystalline orientation, the diffusion of Li to crystalline Si (c-Si) is anisotropic, which acts as the major cause for the fracture of Si anodes in Li-ion batteries. Here, by conducting comprehensive/multi-scale simulation studies based on molecular dynamics and density functional theory, we elucidate how and why Li diffusion in c-Si is anisotropic. We found that Li ions diffuse to c-Si by following a particular atomic-scale space corresponding to the lowest value of the valence orbital in c-Si, causing Li ions to take a tortuous diffusion pathway. The degree of the tortuosity of the pathway differs depending on the crystallographic orientation of Si, and it acts as the major cause for anisotropic lithiation. We also develop a structural parameter that can quantitatively evaluate the orientation dependency of the lithiation of c-Si.",
author = "Choi, {Yong Seok} and Park, {Jun Hyoung} and Ahn, {Jae Pyoung} and Jae-chul Lee",
year = "2017",
month = "12",
day = "1",
doi = "10.1038/s41598-017-14374-0",
language = "English",
volume = "7",
journal = "Scientific Reports",
issn = "2045-2322",
publisher = "Nature Publishing Group",
number = "1",

}

TY - JOUR

T1 - Interfacial Reactions in the Li/Si diffusion couples

T2 - Origin of Anisotropic Lithiation of Crystalline Si in Li-Si batteries

AU - Choi, Yong Seok

AU - Park, Jun Hyoung

AU - Ahn, Jae Pyoung

AU - Lee, Jae-chul

PY - 2017/12/1

Y1 - 2017/12/1

N2 - As opposed to the common understanding that diffusion into a cubic-structured single crystal is independent of its crystalline orientation, the diffusion of Li to crystalline Si (c-Si) is anisotropic, which acts as the major cause for the fracture of Si anodes in Li-ion batteries. Here, by conducting comprehensive/multi-scale simulation studies based on molecular dynamics and density functional theory, we elucidate how and why Li diffusion in c-Si is anisotropic. We found that Li ions diffuse to c-Si by following a particular atomic-scale space corresponding to the lowest value of the valence orbital in c-Si, causing Li ions to take a tortuous diffusion pathway. The degree of the tortuosity of the pathway differs depending on the crystallographic orientation of Si, and it acts as the major cause for anisotropic lithiation. We also develop a structural parameter that can quantitatively evaluate the orientation dependency of the lithiation of c-Si.

AB - As opposed to the common understanding that diffusion into a cubic-structured single crystal is independent of its crystalline orientation, the diffusion of Li to crystalline Si (c-Si) is anisotropic, which acts as the major cause for the fracture of Si anodes in Li-ion batteries. Here, by conducting comprehensive/multi-scale simulation studies based on molecular dynamics and density functional theory, we elucidate how and why Li diffusion in c-Si is anisotropic. We found that Li ions diffuse to c-Si by following a particular atomic-scale space corresponding to the lowest value of the valence orbital in c-Si, causing Li ions to take a tortuous diffusion pathway. The degree of the tortuosity of the pathway differs depending on the crystallographic orientation of Si, and it acts as the major cause for anisotropic lithiation. We also develop a structural parameter that can quantitatively evaluate the orientation dependency of the lithiation of c-Si.

UR - http://www.scopus.com/inward/record.url?scp=85032274343&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85032274343&partnerID=8YFLogxK

U2 - 10.1038/s41598-017-14374-0

DO - 10.1038/s41598-017-14374-0

M3 - Article

VL - 7

JO - Scientific Reports

JF - Scientific Reports

SN - 2045-2322

IS - 1

M1 - 14028

ER -