Molecular dynamics study on the microstructure of CH3COOLi solutions with different concentrations

TL;DR

This study uses molecular dynamics simulations to analyze how the microstructure of CH3COOLi aqueous solutions changes with concentration, providing insights into their potential as safer electrolytes for lithium-ion batteries.

Contribution

It offers a detailed molecular-level analysis of the microstructural variations in CH3COOLi solutions across different concentrations, highlighting interactions especially involving anions.

Findings

Radial distribution function peak at 2.9 Å remains unchanged with concentration.

Microstructures of small components are stable across concentrations.

Spatial structures evolve from a broader perspective as concentration increases.

Abstract

Due to the toxic and flammable problems of organic electrolytes, the study on concentrated aqueous system for lithium ion batteries (LIBs) has attracted wide attention. In this paper, by molecular dynamics simulations, the CH3COOLi aqueous system is considered as the potential concentrated aqueous system for LIBs, and the all variations of the microstructure of the aqueous system from dilution to concentration are analyzed. The details of microstructure are discussed, especially the interactions concerning anions. Among them, the first peak of RDF (radial distribution function) between the Li+ ion and the oxygen atom in CH3COOLi is 2.9 A, which does not change from dilution to concentration. This RDF information further indicates that when the concentration increases, the microstructures of small components formed by any two clusters do not change much, but at same time, the spatial structures constructed by many small components are gradually built up from a broader perspective.