Porous Carbon Interlayer Derived from Traditional Korean Paper for Li-S Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-sulfur (Li-S) batteries offer high theoretical energy density but suffer from poor cycle life due to polysulfide shuttling.
• Effective strategies are needed to mitigate polysulfide migration and improve electrochemical performance.

Purpose of the Study:

• To develop a simple, cost-effective carbon interlayer for improving Li-S battery performance.
• To investigate the role of a porous carbon interlayer in suppressing polysulfide shuttling and enhancing charge transfer.

Main Methods:

• Fabrication of a carbon interlayer from traditional Korean hanji paper.
• Characterization of the carbon interlayer's physical properties (surface area, pore size).
• Integration of the carbon interlayer into Li-S battery cells for electrochemical testing.

Main Results:

• The hanji-derived carbon interlayer exhibited a fibrous porous structure with a surface area of 91.82 m² g⁻¹ and an average pore diameter of 26.63 nm.
• The interlayer effectively captured dissolved lithium polysulfides, suppressed their migration, and reduced cell polarization.
• Li-S cells with the carbon interlayer showed a twofold improvement in discharge capacity after 150 cycles (583 mAh g⁻¹ vs. 230 mAh g⁻¹ at 0.5 C).

Conclusions:

• A simple carbon interlayer derived from hanji paper is a viable strategy for enhancing Li-S battery performance.
• The interlayer's porous structure facilitates polysulfide management, leading to improved capacity retention and cycle life.
• This approach offers a cost-effective method for advancing Li-S battery technology.