Insights into Polymer Electrolyte Stability and Reaction Pathways: A first-principle calculations study

TL;DR

This paper uses first-principle calculations to analyze the electrochemical stability and decomposition pathways of potential polymer electrolyte monomers for solid-state batteries, providing insights into their reactivity under different ionic conditions.

Contribution

It offers a detailed computational analysis of monomer oxidation, reduction potentials, and decomposition pathways, advancing understanding of polymer electrolyte stability.

Findings

Monomers are sensitive to reduction in Li+ environments.

Oxidation sensitivity observed in TFSI- rich regimes.

Decomposition mainly involves CO bond cleavage.

Abstract

This study investigates the electrochemical behavior and decomposition pathways of four monomers, namely PMC, PMC-OH, PeMC-OH, and DEO-EA, which are potential candidates for polymer electrolytes in solid-state batteries. Density functional theory calculations were employed to determine the oxidation and reduction potentials of these monomers near different ions (Li+, TFSI-, and LiTFSI) and their corresponding reorganization energies. The results reveal notable sensitivity of the monomers to reduction in a Li+ rich regime and to oxidation in a TFSI- rich regime. Additionally, the decomposition pathways of the monomers were investigated, focusing on the cleavage of CO bonds. The findings provide insights into the stability and reactivity of these monomers in various electrochemical environments.