Enhancing Lithium-Sulfur Batteries Performance with Mn Atomic Clusters Modified Separator via Promoting Polysulfide...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-sulfur batteries (LSBs) face challenges from lithium polysulfide (LiPS) shuttle effect and slow conversion kinetics, hindering large-scale application.
• Effective strategies are needed to suppress LiPS shuttling and improve the electrochemical performance of LSBs.

Purpose of the Study:

• To develop a novel catalyst for modified separators in LSBs.
• To mitigate the shuttle effect and enhance the conversion kinetics of LiPS.
• To improve the overall performance and cycle life of LSBs.

Main Methods:

• Fabrication of N-doped activated carbon modified with manganese clusters (Mnₓ@NAC) using a ligand-mediated pyrolysis strategy.
• Modification of battery separators with the synthesized Mnₓ@NAC catalyst.
• Electrochemical testing of LSBs with modified separators, including rate performance and long-term cycling stability.

Main Results:

• The Mnₓ@NAC catalyst effectively adsorbs polysulfides and reduces the Gibbs free energy for redox reactions, suppressing LiPS shuttling.
• LSBs with Mnₓ@NAC-modified separators demonstrated excellent rate capability (550 mA h g⁻¹ at 5 C) and cycling stability (675 mA h g⁻¹ after 300 cycles at 1 C).
• High sulfur loading (4.6 mg cm⁻²) LSBs maintained a stable capacity of 612 mA h g⁻¹ after 100 cycles.

Conclusions:

• The Mnₓ@NAC catalyst is a promising material for enhancing the performance of LSBs by addressing key challenges.
• The ligand-mediated pyrolysis strategy provides a facile route for developing advanced modified separators for high-performance energy storage devices.
• This work offers a viable approach for the practical application of lithium-sulfur battery technology.