NMR studies of equilibriums in electrolytes

Glyme-based electrolytes: suitable solutions for next-generation lithium batteries

“…23 Furthermore, the formation constants of ionic pair solutions of lithium salts in G 1 , G 2 , and G 3 were estimated using 7 Li, 11 B and 19 F NMR analyses, which demonstrated that even in solvents with very similar coordination (in terms of the donor and acceptor number values) and dielectric properties, the ionic pair formation constant depended on effects related to ion agglomerate formation, non-covalent interactions between ions and the liquid matrix, as well as the number of interacting centers in the solvent molecules. 24…”

“…Electrolytes formed by dissolving various lithium salts in glymes differing by the ether chain length were initially considered as simple solutions, mainly characterized by the solute concentration. 16–24 Subsequently, the concept of liquid solvated salt-complexes with similar characteristics to those of ionic liquids, i.e. , molten salts, was proposed.…”

“…[8][9][10] Therefore, several research studies have been focusing since nineties on optimizing alternative electrolyte solutions, [11][12][13][14][15] such as those prepared by dissolving a lithium salt in a lowly volatile and modestly flammable ether oligomer with a -(CH2CH2O)unit, that is, ethylene oxide (EO)-glymes. [16][17][18][19][20][21][22][23][24] EObased glymes can be synthesized from ethylene epoxide by various large scale methods, including reaction in alcoholic environment with sodium following the Williamson mechanism, methylation of glycol ether with methyl sulfate, Lewis acid-catalyzed cleavage of ethylene oxide by ether, and reaction of ethylene glycol with alcohol catalyzed polyperfuorosulfonic acid resin at high temperature and pressure. 25 Instead, aliphatic carbonate presently used in the battery electrolyte formulation may be industrially achieved by more complex organic pathways including phosgenation, oxidative carbonylation, reaction of urea with alcohols, reaction of oxiranes with carbon dioxide, through metal carbonate, and by carbonate interchange reaction.…”

Natural abundance 17O, 6Li NMR and molecular modeling studies of the solvation structures of lithium bis(fluorosulfonyl)imide/1,2-dimethoxyethane liquid electrolytes

“…[3][4][5] As a result, designing an electrolyte with favorable molecular interaction between solvent molecules and Li + ions is one of the decisive factors for enhancing cell performance and stability. Studying Li + solvation structures in an electrolyte is thus important for understanding the fundamentals behind the cycling performance of a Li metal anode [6][7][8][9].…”

“…NMR (nuclear magnetic resonance) spectroscopy, an atomic specific, non-destructive and inherently quantitative tool, has been used to elucidate the solvation structures and the ion coordination formulations of glyme electrolytes. [8,[18][19][20][21][22][23][24] As early as in 1999, Hayashi et al [25] employed 7 Li and 13 C NMR to investigate the Li + solvation state of DME/EC binary solvent electrolytes. Plewa-marczewska et al [8] have estimated the formation constants of XCF 3 SO 3 (X= Li + , Na + , K + or n-Bu 4 N + ) and LiBF 4 in glymes (monoglyme-triglyme) systems using a combination of 7 Li, 11 B and 19 F NMR.…”