Imperial College London
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Dr Billy Wu

Faculty of Engineering, Dyson School of Design Engineering

Reader in Electrochemical Design Engineering
 
 
 
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Contact

 

+44 (0)20 7594 6385billy.wu Website

 
 
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Location

 

1M04Royal College of ScienceSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Bonkile:2023:10.1016/j.est.2023.108609,
author = {Bonkile, MP and Jiang, Y and Kirkaldy, N and Sulzer, V and Timms, R and Wang, H and Offer, G and Wu, B},
doi = {10.1016/j.est.2023.108609},
journal = {Journal of Energy Storage},
title = {Coupled electrochemical-thermal-mechanical stress modelling in composite silicon/graphite lithium-ion battery electrodes},
url = {http://dx.doi.org/10.1016/j.est.2023.108609},
volume = {73},
year = {2023}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Silicon is often added to graphite battery electrodes to enhance the electrode-specific capacity, but it undergoes significant volume changes during (de)lithiation, which results in mechanical stress, fracture, and performance degradation. To develop long-lasting and energy-dense batteries, it is critical to understand the non-linear stress behaviour in composite silicon-graphite electrodes. In this study, we developed a coupled electrochemical-thermal-mechanical model of a composite silicon/graphite electrode in PyBaMM (an open-source physics-based modelling platform). The model is experimentally validated against a commercially available LGM50T battery, and the effects of C-rates, depth-of-discharge (DoD), and temperature are investigated. The developed model can reproduce the voltage hysteresis from the silicon and provide insights into the stress response and crack growth/propagation in the two different phases. The stress in the silicon is relatively low at low DoD but rapidly increases at a DoD >~80%, whereas the stress in the graphite increases with decreasing temperature and DoD. At higher C-rates, peak stress in the graphite increases as expected, however, this decreases for silicon due to voltage cut-offs being hit earlier, leading to lower active material utilisation since silicon is mostly active at high DoD. Therefore, this work provides an improved understanding of stress evolution in composite silicon/graphite lithium-ion batteries.
AU  - Bonkile,MP
AU  - Jiang,Y
AU  - Kirkaldy,N
AU  - Sulzer,V
AU  - Timms,R
AU  - Wang,H
AU  - Offer,G
AU  - Wu,B
DO  - 10.1016/j.est.2023.108609
PY  - 2023///
SN  - 2352-152X
TI  - Coupled electrochemical-thermal-mechanical stress modelling in composite silicon/graphite lithium-ion battery electrodes
T2  - Journal of Energy Storage
UR  - http://dx.doi.org/10.1016/j.est.2023.108609
UR  - http://hdl.handle.net/10044/1/106311
VL  - 73
ER  -
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