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09:16
Synthesis of Terpolymers at Mild Temperatures Using Dynamic Sulfur Bonds in Poly(S-Divinylbenzene)
Published on: May 20, 2019
Solid-Liquid Synergy Enables a Trisulfur-Radical-Rich Microenvironment for Accelerated Li-S Conversion Kinetics
Zhiqi Zhao1, Bohai Zhang2,3, Bin Tang3,4
1Henan International Joint Laboratory of Laser Technology in Agriculture Sciences, College of Mechanical & Electrical Engineering, Henan Agricultural University, Zhengzhou, Henan, China.
Advanced Materials (Deerfield Beach, Fla.)
|May 18, 2026
Summary
Researchers developed a new strategy for lithium-sulfur batteries (LSBs) using oxygen vacancies and a high-donor-number solvent. This approach accelerates the rate-determining step (RDS) via trisulfur radicals, significantly improving battery performance and longevity.
Area of Science:
- Materials Science
- Electrochemistry
- Energy Storage
Background:
- Lithium-sulfur batteries (LSBs) offer high theoretical energy density but suffer from slow kinetics and poor cycle life.
- Understanding and controlling the rate-determining steps (RDSs) are critical for improving LSB performance.
Purpose of the Study:
- To propose a synergistic strategy to accelerate the RDS in LSBs.
- To investigate the role of trisulfur radicals as key mediators in enhancing electrochemical reactions.
- To improve the overall electrochemical performance and cycle stability of LSBs.
Main Methods:
- Integration of a template sulfur host with oxygen vacancies and a high-donor-number (high-DN) solvent additive.
- Creation of a localized high-DN microenvironment on the cathode.
- Experimental validation and computational calculations to confirm the mechanism.
Main Results:
- A localized high-DN microenvironment with concentrated trisulfur radicals was established.
- Trisulfur radicals were confirmed as key mediators accelerating the RDS from quasi-liquid-solid to trisulfur radical-mediated conversion.
- LSBs demonstrated excellent stability, retaining 85.4% capacity after 500 cycles at 1 C (0.03% decay per cycle).
- High initial capacities of 659.6 mAh g⁻¹ at 5 C and 1126.9 mAh g⁻¹ at a high sulfur loading (4.6 mg cm⁻²) were achieved.
Conclusions:
- A novel trisulfur radical-mediated catalytic mechanism was presented.
- The strategy effectively overcomes limitations of the intrinsic RDS through combined interface engineering and electrolyte modulation.
- This approach significantly enhances the electrochemical performance and cycle life of lithium-sulfur batteries.
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