Water-in-salt electrolytes - molecular insights to the high solubility of lithium-ion salts.

The recently established water-in-salt electrolyte (WISE) concept indicates the possible application of aqueous electrolytes in lithium-ion batteries (LiBs). The application of this type of highly concentrated electrolyte relies on a proper understanding of their thermodynamically stable solutions. Therefore, fundamental insights regarding the Li[TFSI] solubility in water are important for the rational design of reproducible and stable WISE.