Imperial College London
Dr Yatish Patel

DrYatishPatel

Faculty of Engineering, Department of Mechanical Engineering

Advanced Research Fellow
 
 
 
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Contact

 

yatish.patel

 
 
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Location

 

City and Guilds BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Liu:2019:10.1016/j.apenergy.2019.04.108,
author = {Liu, X and Ai, W and Naylor, Marlow M and Patel, Y and Wu, B},
doi = {10.1016/j.apenergy.2019.04.108},
journal = {Applied Energy},
pages = {489--499},
title = {The effect of cell-to-cell variations and thermal gradients on the performance and degradation of lithium-ion battery packs},
url = {http://dx.doi.org/10.1016/j.apenergy.2019.04.108},
volume = {248},
year = {2019}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The performance of lithium-ion battery packs are often extrapolated from single cell performance however uneven currents in parallel strings due to cell-to-cell variations, thermal gradients and/or cell interconnects can reduce the overall performance of a large scale lithium-ion battery pack. In this work, we investigate the performance implications caused by these factors by simulating six parallel connected batteries based on a thermally coupled single particle model with the solid electrolyte interphase growth degradation mechanism modelled. Experimentally validated simulations show that cells closest to the load points of a pack experience higher currents than cells further away due to uneven overpotentials caused by the interconnects. When a cell with a four times greater internal impedance was placed in the location with the higher currents this actually helped to equalise the cell-to-cell current distribution, however if this was placed at a location furthest from the load point this would cause a ~6% reduction in accessible energy at 1.5 C. The influence of thermal gradients can further affect this current heterogeneity leading to accelerated aging. Simulations show that in all cases, cells degrade at different rates in a pack due to the uneven currents, with this being amplified by thermal gradients. In the presented work a 5.2% increase in degradation rate, from -7.71 mWh/cycle (isothermal) to - 8.11 mWh/cycle (non-isothermal) can be observed. Therefore, the insights from this paper highlight the highly coupled nature of battery pack performance and can inform designs for higher performance and longer lasting battery packs.
AU  - Liu,X
AU  - Ai,W
AU  - Naylor,Marlow M
AU  - Patel,Y
AU  - Wu,B
DO  - 10.1016/j.apenergy.2019.04.108
EP  - 499
PY  - 2019///
SN  - 0306-2619
SP  - 489
TI  - The effect of cell-to-cell variations and thermal gradients on the performance and degradation of lithium-ion battery packs
T2  - Applied Energy
UR  - http://dx.doi.org/10.1016/j.apenergy.2019.04.108
UR  - https://www.sciencedirect.com/science/article/pii/S0306261919307810?via%3Dihub
UR  - http://hdl.handle.net/10044/1/69207
VL  - 248
ER  -
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