Final Report for DE-FG02-93ER14376,Ionic Transport in Electrochemical Media

Halley, J. W.

University of Minnesota

关键词: Membranes;    Plasma Switches;    30 Direct Energy Conversion;    Polymers;    Electrolytes;   

DOI  :  10.2172/952657
RP-ID  :  DOE/ER/14376-1
RP-ID  :  FG02-93ER14376
RP-ID  :  952657

美国|英语

来源: UNT Digital Library

【 摘 要 】

This project was a molecular dynamics study of the relevant issues associated with the structure and transport of lithium in polymer electrolytes such as polyethylene oxide(PEO). In close collaboration with quantum chemist Larry Curtiss and neutron scatterers David Lee Price and Marie-Louise Saboungi at Argonne, we used molecular dynamics to study the local structure and dynamics and ion transport in the polymer. The studies elucidated the mechanism of Li transport in PEO, revealing that the rate limiting step is extremely sensitive to the magnitude of the torsion forces in the backbone of the polymer. Because the torsion forces are difficult to manipulate chemically, this makes it easier to understand why improving the conductivity of PEO based electrolytes has proven to be very difficult. We studied the transport properties of cations in ionic liquids as possible additives to polymer membranes for batteries and fuel cells and found preliminary indications that the transport is enhanced near phase separation in acid-ionic liquid mixtures.