Polymer Electrolytes Based on Poly(ethylenimine)

University Of Oklahoma Norman Campus, Norman OK

Investigators

Abstract

This award focuses on the development of a new family of polymer electrolytes with extraordinary mechanical properties and high ionic conductivities. This plan has two distinct components. (1) a series of fundamental studies of simple, precursor polymer electrolytes that focus on the critical factors controlling ionic conductivity, and (2) the development of a commercializable polymer electrolyte with optimized mechanical and electrical properties. The fundamental studies address a serious problem in the field of ion-conducting polymers, namely that the mechanism of ion transport in these system is as yet poorly understood at the molecular level. The polymer electrolytes proposed for study are based on poly(ethylenimine), PEI. In the fundamental phase of work, attention will be restricted to electrolytes prepared with simple linear PEI and alkyl-substituted PEI, examining the important factors underlying ionic transport such as cation-anion interaction, ion-polymer interactions, and polymer interactions, and polymer segmental motion. These materials will be studied by a variety of techniques, primarily Raman and infrared vibrational spectroscopy, complemented by measurements of ionic conductivity using impedance methods. In addition, thermal characterization with DSC and structural characterization with x-ray diffraction techniques will also be used. The right synthetic versatility available with PEI-based systems allows an extraordinary range of possibilities for the optimization of desirable mechanical and conductivity properties. The results of these studies may lead to the development of a new family of ion-conducting polymers for application as electrolytes in "next generation" high energy density lithium rechargeable batteries.