Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Effects of external pressure on the performance and ageing of single-layer lithium-ion pouch cells
KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.ORCID iD: 0000-0003-4901-5820
KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.ORCID iD: 0000-0001-9203-9313
KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.ORCID iD: 0000-0002-0452-0703
2018 (English)In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 385, p. 18-26Article in journal (Refereed) Published
Abstract [en]

The effects of external compression on the performance and ageing of NMC(1/3)/Graphite single-layer Li-ion pouch cells are investigated using a spring-loaded fixture. The influence of pressure (0.66, 0.99, 1.32, and 1.98 MPa) on impedance is characterized in fresh cells that are subsequently cycled at the given pressure levels. The aged cells are analyzed for capacity fade and impedance rise at the cell and electrode level. The effect of pressure distribution that may occur in large-format cells or in a battery pack is simulated using parallel connected cells. The results show that the kinetic and mass transport resistance increases with pressure in a fresh cell. An optimum pressure around 1.3 MPa is shown to be beneficial to reduce cyclable-lithium loss during cycling. The minor active mass losses observed in the electrodes are independent of the ageing pressure, whereas ageing pressure affects the charge transfer resistance of both NMC and graphite electrodes and the ohmic resistance of the cell. Pressure distribution induces current distribution but the enhanced current throughput at lower pressures cell does not accelerate its ageing. Conclusions from this work can explain some of the discrepancies in non-uniform ageing reported in the literature and indicate coupling between electrochemistry and mechanics.

Place, publisher, year, edition, pages
Elsevier, 2018. Vol. 385, p. 18-26
Keywords [en]
Current distribution, Lithium-ion battery, Mechanics, Non-uniform ageing, Pressure
National Category
Other Chemical Engineering
Identifiers
URN: urn:nbn:se:kth:diva-224547DOI: 10.1016/j.jpowsour.2018.03.020ISI: 000430779400003Scopus ID: 2-s2.0-85043458948OAI: oai:DiVA.org:kth-224547DiVA, id: diva2:1192046
Funder
Swedish Energy Agency, 30770-3StandUp
Note

QC 20180321

Available from: 2018-03-21 Created: 2018-03-21 Last updated: 2018-07-23Bibliographically approved
In thesis
1. Durability Aspects of Fast Charging, Mechanical Constraint, and Inhomogeneity in Lithium-Ion Batteries
Open this publication in new window or tab >>Durability Aspects of Fast Charging, Mechanical Constraint, and Inhomogeneity in Lithium-Ion Batteries
2018 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The development of lithium-ion batteries with higher energy and power density, better safety, and lower cost has significantly contributed to the increased market share of electric vehicles (EVs) in the last decade. However, the expectations of end-users of EVs still require a continuous quest for better performance. One important end-user expectation is the ability of the battery to be charged rapidly, but the durability of lithium-ion batteries could be affected by the fast charging. Hence, detailed investigations are required to understand the extent and mechanism of the degradation for an optimized battery usage and material development.   

In order to meet the high energy and power required in EVs, multiple large-format cells are connected in series and in parallel. Such a condition leads to an uneven distribution of temperature, pressure, and current in a cell or among cells that may cause locally inhomogeneous ageing and accelerate the global battery ageing. This thesis investigates the effects of charging rate, charging protocol, and external compression on battery durability. The impacts of inhomogeneities induced by cell design constraint, and uneven compression and temperature distributions are also addressed. The studies are based LiNi1/3Mn1/3Co1/3O2/graphite cells. Cell housing for a controlled pressure and temperature application was developed. Electrochemical and material characterization techniques were used in the investigation.

The results show that fast charging at a rate equivalent to full charging in 20 minutes (3C rate) or less accelerates battery ageing. The ageing rate is less sensitive to charging rate in a longer charging time, i.e. at 2C and below, where it is determined more by factors such as the extent of full charging. In all cases, the capacity loss is limited by the cyclable lithium loss. External compression of a battery in an optimum range reduces ageing, but compression above or below the optimum range accelerates ageing. Lithium-ion batteries age non-uniformly. Cycling induces an increase in the impedance at the outer radius of curvature of a prismatic cell jellyroll, associated with a loss of contact between the current collector and the electrode coating. An unfavorable current distribution induced by uneven temperature distribution can accelerate battery ageing. 

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2018. p. 56
Series
TRITA-CBH-FOU ; 2018:13
Keywords
Lithium-ion batteries; NMC(111); Graphite; Cycle ageing, Fast-charging; Inhomogeneity; Current distribution; Pressure; Curvature; Temperature.
National Category
Chemical Engineering
Research subject
Chemical Engineering
Identifiers
urn:nbn:se:kth:diva-226512 (URN)978-91-7729-753-6 (ISBN)
Public defence
2018-05-09, F3, Lindstedtsvägen 26, Stockholm, 10:00 (English)
Opponent
Supervisors
Note

QC 20180419

Available from: 2018-04-19 Created: 2018-04-18 Last updated: 2018-04-19Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textScopus

Authority records BETA

Klett, MatildaLindbergh, Göran

Search in DiVA

By author/editor
Mussa, Abdilbari ShifaKlett, MatildaLindbergh, GöranWreland Lindström, Rakel
By organisation
Applied Electrochemistry
In the same journal
Journal of Power Sources
Other Chemical Engineering

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 115 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf