Electrical Conductivity and NMR Studies of PEG and PPG Containing Lithium Salts
Abstract
Complex impedance, differential scanning calorimetry (DSC) and 7Li nuclear magnetic resonance (NMR) studies have been carried out on electrolytes such as poly(propylene glycol) (PPG) and poly(ethylene glycol) mono-methyl-ether (PEG) containing lithium salts. The impedance studies were made over a range of frequencies, temperatures and pressures and were used to obtain values of electrical conductivity. It is shown that the Bendler-Shlesinger (BENSH) formalism is a better representation of the data than the Vogel-Tammann-Fulcher (VTF) equation (or mathematically equivalent Williams-Landel-Ferry (WLF) equation). For both the PEG and PPG based electrolytes the electrical conductivity decreases as pressure increases and the activation volume decreases strongly as temperature increases. However, the activation volume is smaller for the PEG based material and the curvature is opposite for the two materials. All results for the electrolytes are explained qualitatively in terms of free volume.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1999
- Accession Number
- ADA365289
Entities
People
- John J. Fontanella
- M. C. Wintersgill
- P. E. Stallworth
- S. A. Newman
- S. H. Chung
Organizations
- United States Naval Academy