Nanoscale Mechanics of the Solid Electrolyte Interphase on Lithiated-Silicon Electrodes

Haoran Wang, Huck Beng Chew

Research output: Contribution to journalArticlepeer-review

Abstract

The ∼300% volume changes of lithiated silicon electrodes (LixSi) during electrochemical cycling lead to cracking of the solid electrolyte interface (SEI). Here, we report how strain is transferred from LixSi to two primary inorganic SEI components: LiF and Li2O. Our first principle calculations show that LiF, effectively bonded on LixSi at x > 1, enables the entire interface structure to deform plastically by forming delocalized stable voids. In contrast, Li2O tightly bonded to LixSi is stiffer, and deforms rigidly across all x. Our results explain the significantly improved ductility of SEI with higher LiF versus Li2O content observed experimentally.

Original languageEnglish (US)
Pages (from-to)25662-25667
Number of pages6
JournalACS Applied Materials and Interfaces
Volume9
Issue number31
DOIs
StatePublished - Aug 9 2017

Keywords

  • density functional theory
  • lithium-ion batteries
  • mechanical deformation
  • silicon electrodes
  • solid electrolyte interphase

ASJC Scopus subject areas

  • Materials Science(all)

Fingerprint

Dive into the research topics of 'Nanoscale Mechanics of the Solid Electrolyte Interphase on Lithiated-Silicon Electrodes'. Together they form a unique fingerprint.

Cite this