The effect of concentration and ratio of ethylene carbonate and propylene carbonate plasticizers on characteristics of the electrospun PEO-based electrolytes applicable in lithium-ion batteries

摘要

In this study, plasticized electrospun fibers have been designed and fabricated as an electrolyte for lithium-ion batteries using electrospinning method. Polyethylene oxide (PEO) and lithium perchlorate were used as polymer matrix and lithium salt, respectively. Ethylene carbonate and propylene carbonate were applied to investigate the effects of the plasticizer concentration and various EC:PC ratios on the characteristics of the as-spun electrolytes. In addition, the influence of fiber orientation was examined on the ionic conductivity of the nanofibrous electrolytes. Results illustrated that compared with PC, EC can lead to a greater fraction of free ions, lower activation energy (Ea) and so more ionic conductivity. However, the highest room temperature ion conductivity of 0.171 mS.cm(-1) was obtained for the as-spun electrolyte containing EC:PC (3:1) mixture. Moreover, with the increase of PC content, cycle stability of the electrospun electrolytes faded significantly. Furthermore, the ionic conductivity reduced from 0.212 to 0.020 mS.cm(-1) with increasing of the fiber alignment. The results implied that the proposed nanostructured fibers can be a great candidate as free-solvent polymer electrolytes applicable in lithium-ion batteries.