The effect of different poly fibers separator-modified materials on blocking polysulfides for high performance Li-S batteries

Ling Meng; Zhaoxia Sun; Guanghang Sun; Xiting Zhang; Meng Dan; Jin Long; Jian Hu

doi:10.3389/fchem.2022.931201

The effect of different poly fibers separator-modified materials on blocking polysulfides for high performance Li-S batteries

Front Chem. 2022 Aug 11:10:931201. doi: 10.3389/fchem.2022.931201. eCollection 2022.

Authors

Ling Meng¹, Zhaoxia Sun², Guanghang Sun², Xiting Zhang¹, Meng Dan¹, Jin Long², Jian Hu²

Affiliations

¹ Huangpu Hydrogen Innovation Center/Guangzhou Key Laboratory for Clean Energy and Materials, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou, China.
² National Engineering Research Center of Paper-making and Pollution Control, School of Light Industry and Engineering, South China University of Technology, Guangzhou, China.

Abstract

Herein, we reported that KOH impregnation can generate a large number of porous structures with fruitful nitrogen self-doped groups during the carbonized process for poly (p-phenylene terephthalamide) fiber and poly (p-phenylene benzobisoxazole) fiber (denoted as PPTA and PBO, respectively). The intrinsical insulation, volume change, and shuttle effect of polysulfides then can be more significantly improved for the PBO-coated separator than the PPTA case. The discharge capacity primary achieves 1,322 mA h/g, which retains 827 mA h/g even after 200 cycles at 0.2 C for the cell with PBO-coated separator. The reversible specific discharge capacity maintains 841 mA h/g with a Coulomb efficiency of 99.7% at 5 C. The nitrogen self-doped nanocarbon particles are etched by KOH with the simple one-step preparation, which has promising application as Li-S battery cathode.

Keywords: lithium–sulfur battery; poly (p-phenylene benzobisoxazole); poly (p-phenylene terephthalamide); separator; shuttle effect.