Understanding Electrochemical Sulfur-Based Phase Evolution via Complementary Insight from Operando Spatially Resolved...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium/sulfur (Li/S) batteries are a promising technology for large-scale energy storage.
• Key challenges include low power density and the polysulfide shuttle effect, hindering practical application.

Purpose of the Study:

• To investigate the electrochemical mechanisms of Li/S batteries using advanced operando techniques.
• To understand the phase transformations of sulfur during battery cycling.

Main Methods:

• Utilized operando energy dispersive X-ray diffraction (EDXRD) for real-time monitoring of Li/S electrochemistry.
• Employed complementary operando synchrotron-based EDXRD, X-ray absorption spectroscopy (XAS), X-ray powder diffraction (XPD), and ex situ Raman spectroscopy.

Main Results:

• Observed the conversion of α-S₈ to Li₂S_x polysulfide phases during battery discharge.
• Documented the conversion back to β-S₈ during the charging process.

Conclusions:

• Gained fundamental insights into sulfur reduction and oxidation mechanisms in Li/S batteries.
• This understanding is crucial for advancing next-generation Li/S battery performance and material design.