Designing electrolytes by thermodynamics
Yaozu Wang, Huicong Yang, Tianzhao Hu, Nan Piao, Feng Li, Hui–Ming Cheng
Abstract
The immature design theory of electrolytes limits their targeted solvation structure formation and application in batteries. Here, based on the precondition that an electrolyte or solution is a system at a thermodynamic equilibrium state, we try to develop a thermodynamic theory to guide the electrolyte solvation structure design. In this theory, thermodynamic competitive equilibrium between cation-solvent interaction and cation-anion interaction, and between enthalpy and entropy, are two key points determining solute dissolution and formation of various solvation structures. Using this thermodynamic competitive equilibrium theory, the essential principle of all the recently developed electrolyte systems such as high concentration electrolyte, localized high concentration electrolyte, weak solvated electrolyte, anion coordination electrolyte and high-entropy electrolytes can be perfectly explained. We hope that this theory can help accelerate the development of electrolyte study, and enlighten the emergence of advanced electrolytes with unique solvation structures and attractive properties.