The Role of the Anion in Concentrated Electrolytes for Lithium-Sulfur Batteries
Artikel i vetenskaplig tidskrift, 2024

Highly concentrated electrolytes show promise in enhancing lithium-sulfur (Li-S) battery performance by mitigating polysulfide (PS) solubility. The role of the salt anion for the performance improvement(s) is however not well understood. Here a systematic characterization using (concentrated) electrolytes based on three different salts: LiTFSI, LiTf, and LiTDI, in a common DOL:DME solvent mixture is reported for a wide range of physicochemical and electrochemical properties: ionic conductivity, density, viscosity, speciation, and PS solubility. While increased salt concentration in general improves Li-S battery performance, the role of the salt anion introduces complexity. The 2 m LiTDI-based electrolyte, with a slightly higher viscosity and lower PS solubility, outperforms the LiTFSI-based counterpart in terms of accessible reversible capacity. Conversely, the 2 m LiTf-based electrolyte exhibits subpar performance due to the formation of ionic aggregates that renders more free solvent and, therefore higher PS solubility, which, however can be improved by using a 5 m concentrated electrolyte. Hence, using electrolyte salt concentration as a rational design route demands an understanding of the local molecular structure, largely determined/affected by the choice of anion, as well as how it connects to the global properties and in the end improved Li-S battery performance.

highly concentrated electrolytes

lithium-sulfur batteries

high-performance liquid chromatography

COSMO-RS

role of the anion

Författare

Aginmariya Kottarathil

Chalmers, Fysik, C3SE

Politechnika Warszawska

Alistore - European Research Institute

Zaher Slim

Chalmers, Fysik, Materialfysik

Hafiz Ahmad Ishfaq

Kemijski Inštitut

Alistore - European Research Institute

Chalmers, Fysik, C3SE

Steffen Jeschke

Griffith University

G. Z. Zukowska

Politechnika Warszawska

Maciej Jozef Marczewski

Politechnika Warszawska

Katarzyna Lech

Politechnika Warszawska

Patrik Johansson

Chalmers, Fysik, Materialfysik

Alistore - European Research Institute

W Wieczorek

Alistore - European Research Institute

Politechnika Warszawska

Journal of the Electrochemical Society

0013-4651 (ISSN) 1945-7111 (eISSN)

Vol. 171 7 070506

Elektrolyter för Metallorganiska Multivalenta Batterier

Energimyndigheten (50638-1), 2021-01-01 -- 2024-12-31.

Vetenskapsrådet (VR) (2020-03988), 2021-01-01 -- 2024-12-31.

Nästa generations batterier

Vetenskapsrådet (VR) (2021-00613), 2021-12-01 -- 2032-12-31.

Ämneskategorier

Oorganisk kemi

Fysikalisk kemi

Materialkemi

Den kondenserade materiens fysik

DOI

10.1149/1945-7111/ad5b8c

Mer information

Senast uppdaterat

2024-08-05