New Ionic Liquids for Electrochemical Devices: Fundamentals and Applications

Georgia Tech Research Corporation, Atlanta GA

Investigators

Abstract

ABSTRACT PI: Paul A. Kohl Institution: Georgia Institute of Technology Proposal Number: 0624620 Title: New Ionic Liquids for Electrochemical Devices: Fundamentals and Applications The goal of this project is the creation and use of new ionic liquid (IL) electrolytes which are environmentally clean ('green') and applicable to electrochemical devices (i.e. batteries, fuel cells, supercapacitors, and electrochemical separations). Low cost, high-energy density, fuel cells and secondary batteries could provide significant energy savings in the electronics and transportation industries. Lowering our nation's energy consumption and enabling cleaner energy usage are high priorities. The 'heart' of all electrochemical devices is the ionic electrolyte that separates the two electrodes and transports the ions. Ionic liquids (ILs) are a promising option for use in electrochemical devices because they can provide wide voltage ranges without the environmental or chemical-interference penalties of tradition solvents. The ions can be chosen for a particular functionality (transport of specific species such as in a carbonate fuel cell) or because they are resistant to oxidation and reduction, providing a wide electrochemical window (as needed in a high voltage battery or supercapacitor). The ability to transport specific ions opens new applications in environmentally friendly electrochemical separations with high selectivity and energy efficiency. The zero vapor pressure of ILs improves the lifetime (do not dry out) and safety (nonflammable) of devices. The simple, high-yield synthesis of ILs is especially interesting because they can lead to large-scale applications in the areas of energy, synthesis, and separations. Intellectual Merit: The scientific impacts of this project will be: (i) the creation of new room temperature ILs, (ii) the discovery of low-cost ILs, and (iii) the advancement in understanding of IL properties (especially viscosity, solubility, conductivity, and electrochemical stability vs. structure). This project will tightly couple specific IL applications to the synthesis and structure-property studies. There are existing applications for ILs in the area of advanced batteries and fuel cells. New and/or improved ILs produced in this project will be used in a variety of (already identified) energy-related devices. Breakthroughs could result in fuel cells, batteries, and capacitors with higher conversion efficiency, reliability, and power. Broad Impact: In addition to existing electrochemical devices, new ILs will hopefully enable new concepts in fuel cell design and operation allowing the transformation of 'unfavorable' operating conditions to 'favorable' conditions, such as lowering the temperature from an unacceptable value to a desirable one. New, low-cost ILs will also provide the medium to carry out high-value electrochemical reactions in the areas of separations and synthesis. The project has beneficial environmental application in electrochemical devices, especially those dealing with energy conversion, 'green' chemistry, and synthesis/separation. The applications envisioned in this project are perfect for undergraduate and graduate programs. The focus on cost-effective (i.e. simple routes) and room-temperature operation lends itself to projects suitable for students from diverse backgrounds at all educational levels.