Details

Autor(en) / Beteiligte

• Ludwig, Kyle B.
• Correll‐Brown, Riordan
• Freidlin, Max
• Garaga, Mounesha N.
• Bhattacharyya, Sahana
• Gonzales, Patricia M.
• Cresce, Arthur V.
• Greenbaum, Steven
• Wang, Chunsheng
• Kofinas, Peter

Titel

Examining the Electrochemical Properties of Hybrid Aqueous/Ionic Liquid Solid Polymer Electrolytes through the Lens of Composition‐Function Relationships

Ist Teil von

• Advanced energy materials, 2023-08, Vol.13 (31), p.n/a

Ort / Verlag

Weinheim: Wiley Subscription Services, Inc

Erscheinungsjahr

2023

Link zum Volltext

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• Solid polymer electrolytes (SPEs) have the potential to meet evolving Li‐ion battery demands, but for these electrolytes to satisfy growing power and energy density requirements, both transport properties and electrochemical stability must be improved. Unfortunately, improvement in one of these properties often comes at the expense of the other. To this end, a “hybrid aqueous/ionic liquid” SPE (HAILSPE) which incorporates triethylsulfonium‐TFSI (S2,2,2) or N‐methyl‐N‐propylpyrrolidinium‐TFSI (Pyr1,3) ionic liquid (IL) alongside H2O and LiTFSI salt to simultaneously improve transport and electrochemical stability is studied. This work focuses on the impact of HAILSPE composition on electrochemical performance. Analysis shows that an increase in LiTFSI content results in decreased ionic mobility, while increasing IL and water content can offset its impact. pfg‐NMR results reveal that preferential lithium‐ion transport is present in HAILSPE systems. Higher IL concentrations are correlated with an increased degree of passivation against H2O reduction. Compared to the Pyr1,3 systems, the S2,2,2 systems exhibit a stronger degree of passivation due to the formation of a multicomponent interphase layer, including LiF, Li2CO3, Li2S, and Li3N. The results herein demonstrate the superior electrochemical stability of the S2,2,2 systems compared to Pyr1,3 and provide a path toward further enhancement of HAILSPE performance via composition optimization. The electrochemical properties polyacrylonitrile‐based “hybrid aqueous/ionic liquid” solid polymer electrolytes (HAILSPEs) are investigated through the lens of composition‐function relationships. Plasticizing HAILSPEs with triethylsulfonium‐TFSI (S2,2,2) or N‐methyl‐N‐propylpyrrolidinium‐TFSI (Pyr1,3) ionic liquid offsets any deleterious effects due to aggregation of LiTFSI that H2O alone cannot overcome. Ionic liquids also assist in passivation against water reduction through the formation of multicomponent solid electrolyte interphases.