Sulfone-Based Low Fluorine Electrolytes for High-Voltage Cobalt-Free Cathodes

Title data

Klein, Michel ; König, Tobias ; Pahari, Debanjana ; Bianchini, Matteo ; Balducci, Andrea:
Sulfone-Based Low Fluorine Electrolytes for High-Voltage Cobalt-Free Cathodes.
In: Advanced Energy & Sustainability Research. Vol. 7 (2026) Issue 4 . - e202500494.
ISSN 2699-9412
DOI: https://doi.org/10.1002/aesr.202500494

Official URL:

Abstract in another language

Replacing commercial cathode active materials with lithium nickel manganese oxide (LNMO, spinel) has the potential to increase the energy density of lithium-ion batteries. However, to successfully utilize this material, an alternative to conventional EC-based electrolytes needs to be found, as this solvent is unstable at potentials above 4.7 V vs. Li+/Li. In this context, a novel electrolyte formulation consisting of lithium difluoro (oxalato) borate (LiDFOB) and ethyl isopropyl sulfone (EiPS) is examined. The LiDFOB salt is investigated at various concentrations and demonstrates a good solubility in the EiPS solvent as well as the ability to passivate the aluminum current collector at high potentials. Additionally, EiPS exhibits a high dielectric constant and outstanding thermal and electrochemical stability. In combination with LNMO electrodes, the 1 M LiDFOB in EiPS electrolyte shows the best performance stability among all tested electrolytes with an average 82 mAh g−1 and a discharge capacity retention of 89%, after 100 cycles at 0.33 C. A subsequent ex situ X-ray photoelectron spectroscopy analysis reveals a thinner cathode-electrolyte interface forming during cycling when using EiPS-based electrolytes compared to a benchmark formulation, as well as a lower LiF content, indicating lower impedance of the CEI.

Further data

Item Type:	Article in a journal
Refereed:	Yes
Keywords:	electrolyte; cathode; lithium-ion battery; LNMO; lithium salt; sulfone
Institutions of the University:	Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Lehrstuhl Anorganische Aktivmaterialien für elektrochemische Energiespeicher Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Lehrstuhl Anorganische Aktivmaterialien für elektrochemische Energiespeicher > Lehrstuhl Anorganische Aktivmaterialien für elektrochemische Energiespeicher - Univ.-Prof. Dr. Matteo Bianchini Research Institutions > Central research institutes > Bayerisches Zentrum für Batterietechnik - BayBatt
Result of work at the UBT:	Yes
DDC Subjects:	500 Science > 540 Chemistry
Date Deposited:	28 May 2026 05:47
Last Modified:	28 May 2026 05:47
URI:	https://eref.uni-bayreuth.de/id/eprint/97750