Structure and mechanisms underlying ion transport in ternary polymer electrolytes containing ionic liquids
Abstract
We use all atom molecular dynamics simulations to investigate the influence of 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) ionic liquid on the structure and transport properties of poly(ethylene oxide) (PEO) polymer electrolytes doped with LiPF6 salt. We observe enhanced diffusivities of the Li+, PF6−, and BMIM+ ions with increasing loading of the ionic liquid. Interplay between the different ion-ion and ion-polymer interactions is seen to lead to a destabilization of the Li–PF6 coordination and increase in the strength of association between the Li+ cations and the polymer backbone. As a consequence, the polymer segmental relaxation times are shown to be only moderately affected by the addition of ionic liquids. The ionic-liquid induced changes in the mobilities of Li+ ions are seen to be correlated to polymer segmental relaxation times. However, the mobilities of BMIM+ ions are seen to be more strongly correlated to the BMIM–PF6 ion-pair relaxation times.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 17, 2017
- Source ID
- 10.1063/1.4976131
Entities
People
- Santosh Mogurampelly
- Venkat Ganesan
Organizations
- Army Research Office
- National Science Foundation
- Robert A. Welch Foundation
- University of Texas at Austin