Peoand Polyphazene Composite Solid State Polymer Electrolytes Blended With LLTO

The lithium metal batteries have become a hot topic in recently years,because the ultra low negative potential(above-3.0401 V)and supreme specific capacity(above 3,860 mAh g-1)as the lithium metal anodes.However,the existing problems caused by the organic electrolytes and lithium dendrite growth limited application of lithium metal batteries in commercial use.In this work,to overcome those safety issues in lithium metal batteries,a sandwich structure composite electrolyte and a 3D ionic conductive polyphosphazene-base solid state electrolyte have been prepared by incorporating LLTO nano?particles and LLTO nano-wires with PEO and polyphosphazene.A sandwich structure electrolytes composed of gel-type polymer/organic-inorganic composite electrolyte/gel-type polymer(SWEs)were prepared by using electrostatic spinning and solution casting method.The electropun PVDF porous thin film can segregate Ti4+ in LLTO nanowires from lithium metal,avoiding the reduction reaction of Ti4+ with lithium metal.This sandwich structure electrolyte revealed a great ionic conductivity up to 3.01 ×10-3 S/cm at room temperature,perfect Li+-transference number over 0.74 and outstanding electrochemical Stability window over 5.0 V.In addition,the SWEs exhibited a stabilization property after 240 h in lithium deposition stripping test with a current density of 1mA/cm2,moreover,the full battery assembled using LiCoO2 as cathode and Li metal as anode shown an excellent capacity retention ratio above 91.8%after 100 cycles at 2 C and good rate performance of 144,132,122,110 and 98 mAh g-1 at 1?5 C,respectively.A 3D ionic conductive polyphosphazene-base solid state electrolyte was prepared by using a 3D electrospun organic-inorganic composite skeleton.The skeleton with high-strength were made of electrostatic spinning polyacrylonitrile(PAN)nanofibers incorporated with the active filler of LLTO nanoparticles for enhanceing the mechanical property and providing channels for Li-ion transport of the skeleton.This 3D ionic conductive polyphosphazene-base solid state electrolyte revealed a great ionic conductivity above 1.26×10-4 S/cm at room temperature,perfect electrochemical stability window above 4.5 V,and outstanding mechanical property up to 2.95 MPa.Our work proposed a new method to develop the electrolyte with outstanding ionic conductivity,good interfacial behaviour as well as the high mechanical property.