Strengthening Aqueous Electrolytes without Strengthening Water.
Angew Chem Int Ed Engl
; 62(35): e202307212, 2023 Aug 28.
Article
em En
| MEDLINE
| ID: mdl-37407432
ABSTRACT
Aqueous electrolytes typically suffer from poor electrochemical stability; however, eutectic aqueous solutions-25â
wt.% LiCl and 62â
wt.% H3 PO4 -cooled to -78 °C exhibit a significantly widened stability window. Integrated experimental and simulation results reveal that, upon cooling, Li+ ions become less hydrated and pair up with Cl- , ice-like water clusters form, and Hâ
â
â
Cl- bonding strengthens. Surprisingly, this low-temperature solvation structure does not strengthen water molecules' O-H bond, bucking the conventional wisdom that increasing water's stability requires stiffening the O-H covalent bond. We propose a more general mechanism for water's low temperature inertness in the electrolyte less favorable solvation of OH- and H+ , the byproducts of hydrogen and oxygen evolution reactions. To showcase this stability, we demonstrate an aqueous Li-ion battery using LiMn2 O4 cathode and CuSe anode with a high energy density of 109â
Wh/kg. These results highlight the potential of aqueous batteries for polar and extraterrestrial missions.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Estados Unidos