In this study a porous poly(ethylene oxide) (PEO) fiber film was prepared by electrospinning technology Additionally PEO-based precursor was coated on the surface of lithium metal anode followed by putting the PEO film and the cathode in order The PEO-based precursor would permeate into the nanofiber film and cathode PEO-based precursor could provide a continuous network of Li ions in electrolyte and between electrode and electrolyte After heating the all-solid-state lithium batteries were fabricated by thermal polymerization The SEM analysis shows that the PEO-based polymer could uniformly fill the gaps in the film and the overall thickness of the electrolyte is less than 40 ?m In addition the well interfacial contact between cathode and electrolyte is the main reason to result in the low interfacial resistance (100Ω) The solid-state electrolytes exhibit good electrochemical stability (onset potential ~5 5V) and good ionic conductivity (10-4 Scm-1 at 60oC) Besides the capacity of the electrolyte prepared by electrospinning is up to 150 mAh/g under 0 1C at 60℃ The capacity of the electrolyte at the high discharge current (7C) still keeps at 25 mAh/g However there is a potential problem with a short circuit due to poor mechanical property In order to improve mechanical property PEO/PVDF polymer electrospun membranes were prepared by mixing PEO and polyvinylidene difluoride (PVDF) to be applied as the PEO-based all-solid-state electrolyte From the result of plating-stripping test a good ability to limit the growth of lithium dendrite was found All the above-mentioned properties demonstrate that the thin electrolyte membrane could be prepared by an electrospun approach and all-solid-state electrolyte with low interfacial resistance is successfully fabricated by coating PEO-based precursor on the lithium metal
Fabricating low interfacial resistance electrolytes by using polyether electrospun membrane for application in all-solid-state lithium batteries
冠廷, 韓. (Author). 2020
Student thesis: Doctoral Thesis