The Newman model for phase-change electrodes: physics-based hysteresis
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Many modern, commercially relevant Li-ion batteries use insertion materials that exhibit lithiation-induced phase change (e.g. lithium iron phosphate, LFP). However, the standard physics-based model—the Newman model—uses a microscopic description of particle lithiation (based on diffusion) that is incapable of describing phase-change behavior and the physical origins of the voltage hysteresis exhibited by such phase-change electrodes. In this work a simple and rational model of hysteretic lithiation (in an electrode comprised of an ensemble of phase-change nanoparticles) is derived using an approach based on minimisation of the Gibbs energy. Voltage hysteresis arises naturally as a prediction of the model. Initially, equations that model the phase-change dynamics in a single particle of active material are considered. These are generalised to a model, termed the composite phase-change model, of a coupled ensemble of particles in a thin electrode. The composite phase-change model is then incorporated into the framework of a classical Newman model, allowing for the inclusion of transport effects in the electrolyte and electrode conductivity. The resulting modified Newman model is used to predict voltage hysteresis in a graphite/LFP cell. A simulation tool that allows readers to replicate, and extend, the results presented here is provided via the DandeLiion simulator at www.dandeliion.com.
Date Issued
2025-04-04
Date Acceptance
2025-01-31
Citation
Journal of Electrochemical Society, 2025, 172 (4)
ISSN
0013-4651
Publisher
The Electrochemical Society
Journal / Book Title
Journal of Electrochemical Society
Volume
172
Issue
4
Copyright Statement
© 2025 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited.
License URL
Identifier
10.1149/1945-7111/adb219]
Publication Status
Published
Article Number
040501
Date Publish Online
2025-04-04