Composite gel electrolytes prepared from mixtures of poly(acrylonitrile) (PAN), ethylene carbonate (EC), propylene carbonate (PC), and LiClO4 or LiAsF6 have been investigated by complex impedance, differential scanning calorimetry (DSC), and Li-7 nuclear magnetic resonance (NMR) spectroscopy. The ionic conductivity of a gel containing LiAsF6 reaches 10(-2) S/cm at 60-degrees-C. Although the conductivity of the gels approach that found in EC/PC liquid electrolytes, NMR line width, and spin-lattice relaxation time (T1) measurements indicate that even short-range ionic mobility is impeded by the presence of the PAN. As in the case of amorphous polyether-salt polymer electrolytes, the onset of Li-7 motional line narrowing in the gels is strongly correlated with the DSC-determined glass transition temperature.
Li-7 Nmr and Ionic-conductivity Studies of Gel Electrolytes Based On Poly(acrylonitrile)
CROCE, Fausto;
1993-01-01
Abstract
Composite gel electrolytes prepared from mixtures of poly(acrylonitrile) (PAN), ethylene carbonate (EC), propylene carbonate (PC), and LiClO4 or LiAsF6 have been investigated by complex impedance, differential scanning calorimetry (DSC), and Li-7 nuclear magnetic resonance (NMR) spectroscopy. The ionic conductivity of a gel containing LiAsF6 reaches 10(-2) S/cm at 60-degrees-C. Although the conductivity of the gels approach that found in EC/PC liquid electrolytes, NMR line width, and spin-lattice relaxation time (T1) measurements indicate that even short-range ionic mobility is impeded by the presence of the PAN. As in the case of amorphous polyether-salt polymer electrolytes, the onset of Li-7 motional line narrowing in the gels is strongly correlated with the DSC-determined glass transition temperature.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
