Assessment of Simple Models for Molecular Simulation of Ethylene Carbonate and Propylene Carbonate as Solvents for Electrolyte Solutions

Abstract

Progress in understanding liquid ethylene carbonate (EC) and propylene carbonate (PC) on the basis of molecular simulation, emphasizing simple models of interatomic forces, is reviewed. Results on the bulk liquids are examined from the perspective of anticipated applications to materials for electrical energy storage devices. Preliminary results on electrochemical double-layer capacitors based on carbon nanotube forests and on model solid-electrolyte interphase (SEI) layers of lithium ion batteries are considered as examples. The basic results discussed suggest that an empirically parameterized, non-polarizable force field can reproduce experimental structural, thermodynamic, and dielectric properties of EC and PC liquids with acceptable accuracy. More sophisticated force fields might include molecular polarizability and Buckingham-model description of inter-atomic overlap repulsions as extensions to Lennard-Jones models of van der Waals interactions. Simple approaches should be similarly successful also for applications to organic molecular ions in EC/PC solutions, but the important case of Li + deserves special attention because of the particularly strong interactions of that small ion with neighboring solvent molecules. To treat the Li + ions in liquid EC/PC solutions, we identify interaction models defined by empirically scaled partial charges for ion-solvent interactions. The empirical adjustments use more basic inputs, electronic structure calculations and ab initio molecular dynamics simulations, and also experimental results on

Sodium Triflate Water-in-Salt Electrolyte in Advanced Battery Applications: A First-principles Based Molecular Dynamics Study

“…This, in turn, necessitates the implementation of accurate numerical simulations capable of capturing essential details in the system behavior, encompassing local structures, charge transport mechanisms, and chemical reactions at the interfaces with electrodes. While numerous studies have explored computational methods for simulating solvent-in-salt electrolytes and ionic liquids, both in bulk [41][42][43][44][45][46][47][48] and at interfaces [49][50][51][52] , the optimal approach for modeling WiS electrolytes remains uncertain. Despite their high accuracy, firstprinciples calculations come with extensive computational costs.…”

Recycling of a thermoresponsive “catalyst pill”: separation of a molecular catalyst in solid ethylene carbonate in various reactions

“…Currently, EC is mainly used as a battery electrolyte and has found few applications in chemical reactions. 28,29 It is a green and polar solvent which is a solid at ambient temperature with a melting point of 36 °C and a high boiling point of 248 °C. In molten form, it is a low viscosity liquid in comparison with PEG and ILs and dissolves polar ligands and catalysts well.…”