Acta Phys. -Chim. Sin. ›› 2025, Vol. 41 ›› Issue (7): 100082.doi: 10.1016/j.actphy.2025.100082

• ARTICLE • Previous Articles    

PEG-VN modified PP separator for high-stability and high-efficiency lithium-sulfur batteries

Yingtong Shi1, Guotong Xu2, Guizeng Liang1, Di Lan3, Siyuan Zhang4, Yanru Wang1,*(), Daohao Li1,*(), Guanglei Wu1,*()   

  1. 1 State Key Laboratory of Bio-fibers and Eco-textiles, College of Materials Science and Engineering, Qingdao University, Qingdao 266071, Shandong Province, China
    2 Qingdao Engineering Research Center for New Metallic Functional Materials, Characteristic Laboratory of Advanced Metal Functional Materials and Processing in Universities of Shandong, Qingdao Binhai University, Qingdao 266555, Shandong Province, China
    3 School of Automotive Materials, Hubei University of Automotive Technology, Shiyan 442002, Hubei Province, China
    4 School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an 710072, Shaanxi Province, China
  • Received:2025-01-17 Revised:2025-03-14 Accepted:2025-03-18 Published:2025-05-22
  • Contact: Email: yrwang1996@163.com (Yanru Wang)lidaohao@qdu.edu.cn (Daohao Li)wuguanglei@mail.xjtu.edu.cn (Guanglei Wu)
  • Supported by:
    the National Natural Science Foundation of China(52302272); the National Natural Science Foundation of China(52377026); Taishan Scholars and Young Experts Program of Shandong Province(tsqn202211124); Taishan Scholars and Young Experts Program of Shandong Province(tsqn202103057); the Natural Science Foundation of Shandong Province(ZR2022QB023); the Natural Science Foundation of Shandong Province(ZR2024ME046); the Qingchuang Talents Induction Program of Shandong Higher Education Institution (Research and Innovation Team of Marine Polysaccharides Fibers-based Energy Materials), the State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University(ZKT10); Qingchuang Talents Induction Program of Shandong Higher Education Institution (Research and Innovation Team of Marine Polysaccharides Fibers-based Energy Materials), the State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University(GZRC202006)

Abstract:

Lithium-sulfur (Li-S) batteries are regarded as one of the most promising candidates for next generation energy storage systems due to their high theoretical energy density. However, the practical application of Li-S batteries is limited by the low lithium ion (Li+) transport efficiency and the rapid capacity decay caused by the shuttle effect. Herein, we report a composite comprising Polyethylene glycol (PEG) and vanadium nitride (VN) nanosheets coated onto a commercial polypropylene (PP) separator, called PEG-VN@PP separator. The supercatalytic effect and adsorption properties exhibited by the VN nanosheets significantly enhance the conversion of polysulfides, thereby improving both the capacity and stability of Li-S batteries. Due to the coating of PEG, lithium ions are attracted to the polar functional groups, enabling selective transport, which improves the transport efficiency of Li+ and the rate capability of Li-S batteries. The Li-S battery assembled with PEG-VN@PP exhibits a high specific capacity of 782.0 mAh·g−1 and an average capacity decay of 0.048% per cycle at 1C (1675 mA·g−1) for 700 cycles, using the carbon nanotubes/sulfur cathode with a sulfur mass loading of 1.2 mg·cm−2.

Key words: Vanadium nitride, Polyethylene glycol, Separator modification, Shuttle effect, Lithium-sulfur batteries