Localized Water-In-Salt Electrolyte for Aqueous Lithium-Ion Batteries.

Authors :: Jaumaux P
Yang X
Zhang B
Safaei J
Tang X
Zhou D
Wang C
Wang G
Source :: Angewandte Chemie (International ed. in English) [Angew Chem Int Ed Engl] 2021 Sep 01; Vol. 60 (36), pp. 19965-19973. Date of Electronic Publication: 2021 Jul 26.
Publication Year :: 2021
Abstract: Water-in-salt (WIS) electrolytes using super-concentrated organic lithium (Li) salts are of interest for aqueous Li-ion batteries. However, the high salt cost, high viscosity, poor wettability, and environmental hazards remain a great challenge. Herein, we present a localized water-in-salt (LWIS) electrolyte based on low-cost lithium nitrate (LiNO <subscript>3</subscript> ) salt and 1,5-pentanediol (PD) as inert diluent. The addition of PD maintains the solvation structure of the WIS electrolyte, improves the electrolyte stability via hydrogen-bonding interactions with water and NO <subscript>3</subscript> <superscript>-</superscript> molecules, and reduces the total salt concentration. By in situ gelling the LWIS electrolyte with tetraethylene glycol diacrylate (TEGDA) monomer, the electrolyte stability window can be further expanded to 3.0 V. The as-developed Mo <subscript>6</subscript> S <subscript>8</subscript> |LWIS gel electrolyte|LiMn <subscript>2</subscript> O <subscript>4</subscript> (LMO) batteries delivered outstanding cycling performance with an average Coulombic efficiency of 98.53 % after 250 cycles at 1 C.<br /> (© 2021 Wiley-VCH GmbH.)