Imperial College London
Alternate

Prof Gregory Offer

Faculty of Engineering, Department of Mechanical Engineering

Professor in Electrochemical Engineering
 
 
 
//

Contact

 

+44 (0)20 7594 7072gregory.offer Website

 
 
//

Location

 

720City and Guilds BuildingSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Kirkaldy:2022:10.1021/acsaem.2c02047,
author = {Kirkaldy, N and Samieian, MA and Offer, GJ and Marinescu, M and Patel, Y},
doi = {10.1021/acsaem.2c02047},
journal = {ACS Applied Energy Materials},
pages = {13367--13376},
title = {Lithium-ion battery degradation: measuring rapid loss of active silicon in silicon-graphite composite electrodes},
url = {http://dx.doi.org/10.1021/acsaem.2c02047},
volume = {5},
year = {2022}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - To increase the specific energy of commercial lithium-ion batteries, silicon is often blended into the graphite negative electrode. However, due to large volumetric expansion of silicon upon lithiation, these silicon–graphite (Si–Gr) composites are prone to faster rates of degradation than conventional graphite electrodes. Understanding the effect of this difference is key to controlling degradation and improving cell lifetimes. Here, the effects of state-of-charge and temperature on the aging of a commercial cylindrical cell with a Si–Gr electrode (LG M50T) are investigated. The use of degradation mode analysis enables quantification of separate rates of degradation for silicon and graphite and requires only simple in situ electrochemical data, removing the need for destructive cell teardown analyses. Loss of active silicon is shown to be worse than graphite under all operating conditions, especially at low state-of-charge and high temperature. Cycling the cell over 0–30% state-of-charge at 40 °C resulted in an 80% loss in silicon capacity after 4 kA h of charge throughput (∼400 equiv full cycles) compared to just a 10% loss in graphite capacity. The results indicate that the additional capacity conferred by silicon comes at the expense of reduced lifetime. Conversely, reducing the utilization of silicon by limiting the depth-of-discharge of cells containing Si–Gr will extend their lifetime. The degradation mode analysis methods described here provide valuable insight into the causes of cell aging by separately quantifying capacity loss for the two active materials in the composite electrode. These methods provide a suitable framework for any experimental investigations involving composite electrodes.
AU  - Kirkaldy,N
AU  - Samieian,MA
AU  - Offer,GJ
AU  - Marinescu,M
AU  - Patel,Y
DO  - 10.1021/acsaem.2c02047
EP  - 13376
PY  - 2022///
SN  - 2574-0962
SP  - 13367
TI  - Lithium-ion battery degradation: measuring rapid loss of active silicon in silicon-graphite composite electrodes
T2  - ACS Applied Energy Materials
UR  - http://dx.doi.org/10.1021/acsaem.2c02047
UR  - https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000880841300001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=a2bf6146997ec60c407a63945d4e92bb
UR  - https://pubs.acs.org/doi/10.1021/acsaem.2c02047
UR  - http://hdl.handle.net/10044/1/101154
VL  - 5
ER  -
Download