Li-MOF-based ions regulator enabling fast-charging and dendrite-free lithium metal anode

Li metal has been regarded as the holy grail for the next-generation Li-ion battery.Li dendrites issues,however,impede its practical application.In general,prolonging the sand time of Li nucleation and regulating homogeneous Li^(+) flux are effective approaches to suppress the dendrites formation and growth.Regarding this view,a functional polypropylene (PP) separator is developed to regulate ion transportation via a newly designed Li-based metal-organic framework (Li-MOF) coating.The Li-MOF crystallizes in the orthorhombic space group P212121 and features a double-walled three-dimensional (3D) structure with 1D channels.The well-defined intrinsic nanochannels of Li-MOF and the steric-hinerance effect both restrict free migration of anions,contributing to a high Li^(+) transference number of 0.65,which improve the Sand time of Li nucleation.Meanwhile,the Li-MOF coating with uniform porous structure promotes homogeneous Li^(+) flux at the surface of Li metal.Furthermore,the Li-MOF coating layer helps to build solid-electrolyte interphase (SEI) layer that comprises of inorganic Li F and Li_(3)N,which further prohibits the dendrites growth.Consequently,a highly stable Li plating/stripping cycling for over 1000 h is achieved.The functional separator also enables high-performance full lithium metal cells,the high-rate and long-stable cycling performance of Li Ni_(0.8)Mn_(0.1)Co_(0.1)(NMC811)-Li and Li Co O_(2)(LCO)-Li cells further demonstrate the feasibility of this concept.