Insights into polymer electrolyte stability and reaction pathways: A first-principle calculations study

Area of Science:

• Materials Science
• Electrochemistry
• Computational Chemistry

Background:

• Solid-state batteries require stable polymer electrolytes for enhanced safety and performance.
• Understanding monomer electrochemical behavior is crucial for designing new electrolyte materials.

Purpose of the Study:

• To investigate the electrochemical stability and decomposition pathways of four polymer monomers (esters, ethers, carbonates).
• To identify suitable polymer candidates for solid-state battery electrolytes using first-principles calculations.

Main Methods:

• First-principles calculations to determine oxidation/reduction potentials and reorganization energies.
• Ab initio molecular dynamics to simulate reactivity and decomposition pathways.
• Analysis of gaseous and ionic products during interphasial layer formation.

Main Results:

• Monomers exhibit sensitivity to reduction in Li+-rich and oxidation in TFSI--rich environments.
• Carbonate-containing monomers demonstrate superior electrochemical stability against reduction compared to ester and ether monomers.
• Quantified decomposition products provide insights into interphasial layer formation.

Conclusions:

• Carbonate-based monomers are promising candidates for stable solid-state battery electrolytes.
• First-principles calculations effectively predict monomer stability and decomposition mechanisms.
• This research guides the development of safer and more efficient solid-state batteries.