Work

The Newman Model for Phase-Change Electrodes: Physics-Based Hysteresis

Year: 2025

Type: 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 .

Source: Journal of The Electrochemical Society

DOI: 10.1149/1945-7111/adb219

Authors: J. M. Foster, Y. Grudeva, I. Korotkin, E. J. F. Dickinson, G. Offer, G. Richardson

Institutions: University of Portsmouth, University of Southampton, Imperial College London

Language: English

Topic: Advanced Battery Technologies Research

Subfield: Automotive Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $1,950