New Separator Technology Boosts Lithium-Sulfur Battery Life

Researchers have developed a new perovskite-based separator coating that could improve the stability and lifespan of lithium-sulfur (Li-S) batteries, addressing one of the major challenges preventing the technology from reaching wider commercial use.

The research was conducted by Gyeongsang National University in South Korea in collaboration with Energy 11 Co., the Korea Basic Science Institute, Jeonbuk National University and Xi’an University of Technology in China.

Li-S batteries are considered a promising next-generation energy storage technology because they offer a theoretical energy density of around 2,600 Wh/kg and specific capacity of 1,675 mAh/g. However, their performance can decline quickly due to the “polysulfide shuttle effect,” where sulfur compounds move between the battery electrodes during charging and discharging.

To tackle this issue, the researchers developed a dual-site-doped perovskite oxide coating for the battery separator. The material uses strontium and iron at different sites within its structure to perform two important functions. Strontium helps improve the capture of polysulfides, while iron supports faster conversion reactions. Together, these functions help reduce unwanted polysulfide movement while improving battery reaction efficiency.

Testing showed that cells using the modified separator maintained stable cycling for more than 500 cycles at a 2C rate, with capacity declining by only 0.04% per cycle. The material also supported improved lithium-ion movement and better utilization of active battery materials.

Importantly, the researchers tested the technology in pouch cells as well as laboratory-scale coin cells, providing further evidence of its potential for practical battery applications.

The development demonstrates how advanced separator materials could help improve the cycle life and performance of Li-S batteries, supporting their progress toward future high-energy-density storage applications.