Change search
ReferencesLink to record
Permanent link

Direct link
Electrochemical Characterization and Temperature Dependency of Mass-Transport Properties of LiPF6 in EC:DEC
KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Applied Electrochemistry.ORCID iD: 0000-0003-2112-6115
KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Applied Electrochemistry.ORCID iD: 0000-0002-9392-9059
KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Applied Electrochemistry.ORCID iD: 0000-0001-9203-9313
2015 (English)In: Journal of the Electrochemical Society, ISSN 0013-4651, Vol. 162, no 3, A413-A420 p.Article in journal (Refereed) Published
Abstract [en]

Mass transport in the electrolyte is one of the limiting processes when it comes to the power density and energy efficiency of lithium-ion batteries. Electrolyte characterizations are therefore of utmost importance. This study reports the ionic conductivity, diffusion coefficient, lithium-ion transport number, and thermodynamic enhancement factor, as well as density and viscosity, for the electrolyte LiPF6 in EC:DEC (1 1, by weight) at 10 degrees C, 25 degrees C, and 40 degrees C and for concentrations between 0.5 M and 1.5 M. By combining mathematical modeling and three experiments: conductivity measurements, concentration cells, and galvanostatic polarizations, the mass transport phenomena were fully characterized. All parameters were found to vary strongly with both concentration and temperature proving that temperature dependent parameters are essential when studying thermal behavior of lithium-ion batteries. Moreover, conductivity increased with temperature and showed a local maximum at around 1 M within the concentration range at all temperatures. The other parameters either showed a continuous decrease (diffusion coefficient and lithiumion transport number) or increase (thermodynamic enhancement factor) with concentration at all temperatures. Limited liquid range leading to solvent crystallization at 10 degrees C leads to very poor performance, possibly due to the strong coordination between the lithium ion and the crystallizing species, EC. Overall, the studied electrolyte is found to perform poorly compared to previously studied systems.

Place, publisher, year, edition, pages
2015. Vol. 162, no 3, A413-A420 p.
Keyword [en]
Diffusion, Electric batteries, Electrolytes, Energy efficiency, Ions, Lithium, Lithium alloys, Lithium compounds, Lithium-ion batteries, Temperature, Transport properties Concentration ranges, Conductivity measurements, Electrochemical characterizations, Galvanostatic polarization, Lithium-ion transport, Solvent crystallizations, Temperature dependencies, Temperature dependent
National Category
Materials Engineering
URN: urn:nbn:se:kth:diva-162975DOI: 10.1149/2.0641503jesISI: 000349823700024ScopusID: 2-s2.0-84923323697OAI: diva2:799643

QC 20150331

Available from: 2015-03-31 Created: 2015-03-26 Last updated: 2015-05-22Bibliographically approved
In thesis
1. Thermal Aspects and Electrolyte Mass Transport in Lithium-ion Batteries
Open this publication in new window or tab >>Thermal Aspects and Electrolyte Mass Transport in Lithium-ion Batteries
2015 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Temperature is one of the most important parameters for the performance, safety, and aging of lithium-ion batteries and has been linked to all main barriers for widespread commercial success of electric vehicles.

The aim of this thesis is to highlight the importance of temperature effects, as well as to provide engineering tools to study these.

The mass transport phenomena of the electrolyte with LiPF6  in EC:DEC was fully characterized in between 10 and 40 °C and 0.5 and 1.5 M, and all mass transport properties were found to vary strongly with temperature.

A superconcentrated electrolyte with LiTFSI in ACN was also fully characterized at 25 °C, and was found to have very different properties and interactions compared to LiPF6  in EC:DEC.

The benefit of using the benchmarking method termed electrolyte masstransport resistivity (EMTR) compared to using only ionic conductivity was illustrated for several systems, including organic liquids, ionic liquids, solid polymers, gelled polymers, and electrolytes containing flame-retardant additives.

TPP, a flame-retardant electrolyte additive, was evaluated using a HEV load cycle and was found to be unsuitable for high-power applications such as HEVs.

A large-format commercial battery cell with a thermal management system was characterized using both experiments and a coupled electrochemical and thermal model during a PHEV load cycle. Different thermal management strategies were evaluated using the model, but were found to have only minor effects since the limitations lie in the heat transfer of the jellyroll.

Abstract [sv]

Temperatur är en av de viktigaste parametrarna gällande ett litiumjonbatteris prestanda, säkerhet och åldring och har länkats till de främsta barriärerna för en storskalig kommersiell framgång för elbilar.

Syftet med den här avhandlingen är att belysa vikten av temperatureffekter, samt att bidra med ingenjörsverktyg att studera dessa.

Masstransporten för elektrolyten LiPF6  i EC:DEC karakteriserades fullständigt i temperaturintervallet 10 till 40 °C för LiPF6-koncentrationer på 0.5 till 1.5 M. Alla masstransport-egenskaper fanns variera kraftigt med temperaturen.

Den superkoncentrerade elektrolyten med LiTFSI i ACN karakteriserades även den fullständigt vid 25 °C. Dess egenskaper och interaktioner fanns vara väldigt annorlunda jämfört med LiPF6  i EC:DEC.

Fördelen med att använda utvärderingsmetoden elektrolytmasstransportresistivitet (EMTR) jämfört med att endast mäta konduktivitet illustrerades för flertalet system, däribland organiska vätskor, jonvätskor, fasta polymerer, gellade polymerer, och elektrolyter

med flamskyddsadditiv.

Flamskyddsadditivet TPP utvärderades med en hybridbils-lastcykel och fanns vara olämplig för högeffektsapplikationer, som hybridbilar.

Ett kommersiellt storformatsbatteri med ett temperatur-kontrollsystem karakteriserades med experiment och en kopplad termisk och elektrokemisk modell under en lastcykel utvecklad för plug-inhybridbilar. Olika strategier för kontroll av temperaturen utvärderades, men fanns bara ha liten inverkan på batteriets temperatur då begränsningarna för värmetransport ligger i elektrodrullen, och inte i batteriets metalliska ytterhölje.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2015. 60 p.
TRITA-CHE-Report, ISSN 1654-1081 ; 2015:22
Energy storage, Lithium-ion batteries, Electrolytes, Temperature, Modeling, Hybrid electric vehicle, Plug-in hybrid electric vehicle
National Category
Chemical Engineering
Research subject
Chemical Engineering
urn:nbn:se:kth:diva-166857 (URN)978-91-7595-584-1 (ISBN)
Public defence
2015-06-11, D2, Lindstedtsvägen 5, KTH, Stockholm, 10:00 (English)
Swedish Hybrid Vehicle Center

QC 20150522

Available from: 2015-05-22 Created: 2015-05-20 Last updated: 2016-02-02Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Lundgren, HenrikBehm, MårtenLindbergh, Göran
By organisation
Applied Electrochemistry
In the same journal
Journal of the Electrochemical Society
Materials Engineering

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 245 hits
ReferencesLink to record
Permanent link

Direct link