uu.seUppsala universitets publikationer
Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Cation Ordering and Oxygen Release in LiNi0.5-xMn1.5+xO4-y (LNMO)—In Situ Neutron Diffraction and Performance in Li-Ion Full Cells
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.ORCID-id: 0000-0002-8658-8938
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
Scania CV AB.
Visa övriga samt affilieringar
2018 (Engelska)Konferensbidrag, Muntlig presentation med publicerat abstract (Refereegranskat)
Abstract [en]

LiNi0.5Mn1.5O4 (LNMO) is a promising spinel-type positive electrode for lithium ion batteries as it operates at high voltage and possesses high power capability. However, rapid performance degradation in full cells, especially at elevated temperatures, is a problem. There has been a considerable interest in its crystal structure as this is known to affect its electrochemical performance. LNMO can adopt a P4332 (cation ordered) or Fd-3m (cation disordered) arrangement depending on the synthesis conditions. Most of the studies in literature agree on better electrochemical performance for disordered LNMO [1], however, a clear understanding of the reason for this behaviour is still lacking. This partly arises from the fact that synthesis conditions leading to disordering also lead to oxygen deficiency, rock-salt impurities and therefore generate some Mn3+ [2]. Most commonly, X-ray diffraction is used to characterize these materials, however, accurate structural analysis is difficult due to the near identical scattering lengths of Mn and Ni. This is not the case for neutron diffraction. In this study, an in-situ neutron diffraction heating-cooling experiment was conducted on slightly Mn-rich LNMO under pure oxygen atmosphere in order to investigate relationship between disordering and oxygen deficiency. The study shows for the first time that there is no direct relationship between oxygen loss and cation disordering, as disordering starts prior to oxygen release. Our findings suggest that it is possible to obtain samples with varying degrees of ordering, yet with the same oxygen content and free from impurities. In the second part of the study, highly ordered, partially ordered and fully disordered samples have been tested in LNMO∥LTO (Li4Ti5O12) full cells at 55 °C. It is shown that differences in their performances arise only after repeated cycling, while all the samples behave similarly at the beginning of the test. The difference is believed to be related to instabilities of LNMO at higher voltages, that is, in its lower lithiation states.

[1] A. Manthiram, K. Chemelewski, E.-S. Lee, Energy Environ. Sci. 7 (2014) 1339.

[2] M. Kunduraci, G.G. Amatucci, J. Power Sources. 165 (2007) 359–367.

Ort, förlag, år, upplaga, sidor
Boston, MA, USA, 2018.
Nationell ämneskategori
Materialkemi
Identifikatorer
URN: urn:nbn:se:uu:diva-375838OAI: oai:DiVA.org:uu-375838DiVA, id: diva2:1284660
Konferens
2018 MRS Fall Meeting, Boston, MA, USA, November 25-30, 2018
Forskningsfinansiär
StandUpTillgänglig från: 2019-02-01 Skapad: 2019-02-01 Senast uppdaterad: 2019-09-25Bibliografiskt granskad

Open Access i DiVA

Fulltext saknas i DiVA

Övriga länkar

https://www.mrs.org/fall2018

Personposter BETA

Aktekin, BurakBrant, WilliamValvo, MarioBrandell, DanielEdström, Kristina

Sök vidare i DiVA

Av författaren/redaktören
Aktekin, BurakBrant, WilliamValvo, MarioBrandell, DanielEdström, Kristina
Av organisationen
Strukturkemi
Materialkemi

Sök vidare utanför DiVA

GoogleGoogle Scholar

urn-nbn

Altmetricpoäng

urn-nbn
Totalt: 216 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf