Matrix-Assisted Laser Desorption Ionization Mass Spectrometry: An Efficient Approach to Monitor Lithium-Ion Battery...

Area of Science:

• Electrochemistry
• Materials Science
• Analytical Chemistry

Background:

• Understanding lithium-ion battery (LIB) aging requires characterizing electrode-electrolyte interfaces and electrolyte composition.
• Molecular characterization of LIB components is crucial but challenging due to sample instability, especially in the presence of moisture.
• Current analytical methods often require handling samples in controlled atmospheres, with degradation risks during transfer.

Purpose of the Study:

• To evaluate matrix assisted laser desorption ionization high-resolution mass spectrometry (MALDI-HRMS) for analyzing LIB electrolytes.
• To assess the stability of LIB electrolytes under air exposure in both liquid and solid states.
• To determine the suitability of MALDI-HRMS for monitoring electrolyte degradation.

Main Methods:

• Analysis of electrolytes containing LiPF6, LiFSI, LiDFOB, and LiPO2F2 in EC/EMC solvents using MALDI-HRMS.
• Exposure of liquid and solid-state electrolytes to air to induce aging.
• Monitoring electrolyte degradation using MALDI-HRMS after air exposure.

Main Results:

• MALDI-HRMS enabled rigorous monitoring of electrolyte degradation following air exposure.
• Solid-state electrolytes exhibited no degradation over 24 hours of air exposure.
• Liquid-state electrolytes showed degradation within 30 minutes of air exposure.

Conclusions:

• Solid-state electrolytes maintain molecular integrity during transfer to the mass spectrometer.
• MALDI-HRMS is a relevant technique for studying lithium-ion battery electrolyte degradation.
• The solid-state approach offers significant advantages for sample analysis and stability.