Characterization of Electrospun PVdF Fiber-Based Polymer Electrolytes
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- 作者：Sung Won Choi ; Jeong Rae Kim ; Young Rack Ahn ; Seong Mu Jo ; Elton J. Cairns
- 刊名：Chemistry of Materials
- 出版年：2007
- 出版时间：January 9, 2007
- 年：2007
- 卷：19
- 期：1
- 页码：104 - 115
- 全文大小：644K
- 年卷期：v.19,no.1(January 9, 2007)
- ISSN：1520-5002
文摘
Porous PVdF fiber-based membranes with a three-dimensional network structure, high porosity, largeelectrolyte solution uptake, and adequate mechanical properties were prepared by an electrospinningtechnique using various mixed-solvent compositions with poly(vinylidene fluoride) (PVdF). Their physicalproperties, including surface morphology, average fiber diameter, pore size, and electrolyte solution uptake,strongly depended on the composition of the polymer solution used for electrospinning. From X-raydiffraction and FT-Raman data, we found the PVdF membranes to have mixed-crystal structure sof FormII (
-type) and Form III (
-type). Electrospun PVdF fiber-based polymer electrolytes were prepared byimmersing porous PVdF membranes into 1 M LiPF6 electrolyte solutions. On the basis of FT-Ramandata of the PVdF fiber-based polymer electrolytes, it was shown that ethylene carbonate molecules mainlyparticipated in the solvation of the lithium salt. Moreover, with the exception of diethyl carbonate, thesealiphatic carbonate molecules strongly interacted with the PVdF chain. The polymer electrolytes exhibitedhigh ionic conductivities up to 1.0 × 10-3 S/cm at room temperature, and wide electrochemical stabilitywindows of 0.0 to 4.5 V vs Li/Li+. The ionic conductivity of the PVdF fiber-based polymer electrolytesdepended on the physicochemical properties of the 1 M LiPF6 electrolyte solution inside the pores, whereastheir electrochemical properties were enhanced by the interaction between the PVdF chain and the aliphaticcarbonate molecules. Thus, prototype cells with PVdF fiber-based polymer electrolytes showed a rangeof different charge/discharge properties according to the solvent composition of the 1 M LiPF6 electrolytesolutions and the C-rate. In addition, the cycling performances depended on the electrochemical andspectroscopic properties of the electrospun PVdF fiber-based polymer electrolytes.
-type) and Form III (-type). Electrospun PVdF fiber-based polymer electrolytes were prepared byimmersing porous PVdF membranes into 1 M LiPF6 electrolyte solutions. On the basis of FT-Ramandata of the PVdF fiber-based polymer electrolytes, it was shown that ethylene carbonate molecules mainlyparticipated in the solvation of the lithium salt. Moreover, with the exception of diethyl carbonate, thesealiphatic carbonate molecules strongly interacted with the PVdF chain. The polymer electrolytes exhibitedhigh ionic conductivities up to 1.0 × 10-3 S/cm at room temperature, and wide electrochemical stabilitywindows of 0.0 to 4.5 V vs Li/Li+. The ionic conductivity of the PVdF fiber-based polymer electrolytesdepended on the physicochemical properties of the 1 M LiPF6 electrolyte solution inside the pores, whereastheir electrochemical properties were enhanced by the interaction between the PVdF chain and the aliphaticcarbonate molecules. Thus, prototype cells with PVdF fiber-based polymer electrolytes showed a rangeof different charge/discharge properties according to the solvent composition of the 1 M LiPF6 electrolytesolutions and the C-rate. In addition, the cycling performances depended on the electrochemical andspectroscopic properties of the electrospun PVdF fiber-based polymer electrolytes.