Related Experiment Video
Updated: Oct 14, 2025
10:41
The Effect of Charging and Discharging Lithium Iron Phosphate-graphite Cells at Different Temperatures on Degradation
Published on: July 18, 2018
15.7K
Cycling-induced structural damage/degradation of electrode materials-microscopic viewpoint
1Materials Program, Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506, United States of America.
Nanotechnology
|November 3, 2021
Summary
Lithiation causes damage in silicon anodes for lithium-ion batteries, contrary to previous models. This study reveals how Li-Si compound formation leads to cracking and provides formulas for crack growth and healing during battery cycling.
Area of Science:
- Materials Science
- Electrochemistry
- Computational Mechanics
Background:
- Continuum mechanics models fail to explain lithiation-induced damage in battery electrode materials.
- Experimental observations show structural degradation during the lithiation phase of silicon anodes.
Purpose of the Study:
- To investigate the mechanisms of lithiation-induced damage in silicon anodes.
- To develop analytical models for crack growth and healing in silicon anodes during battery cycling.
Main Methods:
- First-principle analysis of silicon atom interactions using the Stillinger-Weber potential.
- Calculation of engineering-tensile strain for Li-Si intermetallic compound formation.
- Development of analytical formulas for crack dynamics based on mass flux and crack tip migration rate.
Main Results:
- Determined critical separation for Si-Si bond rupture.
- Identified Li-Si intermetallic compound formation as a cause of cracking and cavitation.
- Derived formulas for crack growth during lithiation and healing during de-lithiation.
Conclusions:
- Lithiation-induced damage in silicon anodes is driven by Li-Si intermetallic compound formation.
- Crack behavior (growth/healing) is governed by state of charge, crack tip radius, and local electromotive force.
