摘要
Despite the high theoretical specific capacity,the main challenges of rechargeable lithium-sulfur(Li-S)batteries,including the unceasing shuttle of soluble lithium polysulfides(LiPSs)and severe Li corrosion,seriously hinder their commercial and practical applications.Herein,a bifunctional polyvinyl alcohol/poly(lithium acrylate)(C-PVA/PAA-Li)composite nanofiber separator is developed to address the main challenges in Li-S batteries by simultaneously allowing rapid lithium ion transport and ionic shielding of polysulfides.The C-PVA/PAA-Li composite nanofiber membrane is prepared via the facile electrospinning strategy,followed by thermal crosslinking and in-situ lithiation processes.Differing from the conventional Celgard-based coating methods accompanied by impaired lithium ion transport efficiency,the C-PVA/PAA-Li composite nanofiber membrane possesses well-developed porous structures and high ionic conductivity,thus synergistically reducing the charge transfer resistance and inhibiting the growth of lithium dendrites.The resulting Li-S batteries exhibit an ultra-low fading rate of 0.08%per cycle after 400 cycles at 0.2 C,and a capacity of 633 mAhg−1 at a high current density of 3 C.This study presents an inspiring and promising strategy to fabricate emerging dual-functional separators,which paves the pathway for the practical implementation of ultra-stable and reliable Li-S battery systems.
基金
The authors are grateful for the financial support from the National Natural Science Foundation of China(No.21604010)
the Natural Science Foundation of Shanghai(No.18ZR1401600)
“Chenguang Program”supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.16CG39)
Shanghai Scientific and Technological Innovation Project(No.18JC1410600).
