In the present work we develop a scalable and inexpensive design for lithium- sulfur （Li-S） batteries by capping a flexible gel polymer/carbon nanofiber （CNF） composite membrane onto a free-standing and binder-fre...In the present work we develop a scalable and inexpensive design for lithium- sulfur （Li-S） batteries by capping a flexible gel polymer/carbon nanofiber （CNF） composite membrane onto a free-standing and binder-free CNF ＋ ni2s6 cathode, thus achieving a three-dimensional （3D） structural design. The CNF network is used as the current collector and S holder to overcome the insulating nature and volume expansion of S, while the composite membrane comprises a gel polymer poly（vinylidene fluoride-co-hexafluoropropylene） （PVDF-HFP）, and CNF additive is used as an interlayer to trap polysulfides and recycle the remaining S species, leading to a high specific capacity and long cycle life. This 3D structure enables excellent cyclability for 500 cycles at 0.5℃ with a small capacity decay of 0.092% per cycle. Furthermore, an outstanding cycle stability was also achieved at even higher current densities （1.0 to 2.0℃）, indicating its good potential for practical applications of Li-S batteries.展开更多
文摘In the present work we develop a scalable and inexpensive design for lithium- sulfur （Li-S） batteries by capping a flexible gel polymer/carbon nanofiber （CNF） composite membrane onto a free-standing and binder-free CNF ＋ ni2s6 cathode, thus achieving a three-dimensional （3D） structural design. The CNF network is used as the current collector and S holder to overcome the insulating nature and volume expansion of S, while the composite membrane comprises a gel polymer poly（vinylidene fluoride-co-hexafluoropropylene） （PVDF-HFP）, and CNF additive is used as an interlayer to trap polysulfides and recycle the remaining S species, leading to a high specific capacity and long cycle life. This 3D structure enables excellent cyclability for 500 cycles at 0.5℃ with a small capacity decay of 0.092% per cycle. Furthermore, an outstanding cycle stability was also achieved at even higher current densities （1.0 to 2.0℃）, indicating its good potential for practical applications of Li-S batteries.
