Complex permittivity-dependent plasma confinement-assisted growth of asymmetric vertical graphene nanofiber membrane for high-performance Li-S full cells

Vertical graphene(VG),possessing superior chemical,physical,and structural peculiarities,holds great promise as a building block for constructing a high-energy density lithium-sulfur(Li-S)battery.Therefore,it is desirable to develop a new VG growth technique with a novel structure to enable wide applications.Herein,we devise a novel complex permittivity-dependent plasma confinement-assisted VG growth technique,via asymmetric growing a VG layer on one side of N-doped carbon nanofibers for the first time,using a unique lab-built high flux plasma-enhanced chemical vapor deposition system,as a bifunctional nanofiber membrane to construct Li-S batteries with low neg-ative/positive(N/P)and electrolyte/sulfur(E/S)ratios.The unique nanofiber membrane could simultaneously protect the cathode and anode,enabling an excellent electrochemical performance with low N/P and E/S ratios in Li-S bat-teries.Such a full cell delivers high gravimetric energy density and volumetric energy density of 340 Wh kg^(-1) and 547 Wh L^(-1),respectively,at low N/P(2:1)and E/S(4:1)ratios.Furthermore,a pouch cell achieves a high areal capacity of 7.1 mAh cm^(-2) at a sulfur loading of 6 mg cm^(-2).This work put forward a novel pathway for the design of high-energy density Li-S batteries.