Publication Date


Document Type


Committee Members

Hong Huang (Committee Chair), Raghavan Srinivasan (Committee Member), Henry Daniel Young (Committee Member)

Degree Name

Master of Science in Materials Science and Engineering (MSMSE)


Ionic liquids (ILs) have attracted much attention in electrochemical energy storage systems for their advantageous properties over traditional lithium salt/carbonate solvent electrolyte in terms of higher electrochemical potential windows, comparable ionic conductivity, negative vapor pressure and non-flammability. Ionic liquids can be used as the solvent-free electrolyte in electrochemical double layer capacitors (EDLCs) or can act as the important additives to the carbonate electrolyte in lithium ion batteries (LIBs). Recently, lithium ion capacitors (LICs) have emerge as a novel energy storage system to satisfy the demands for higher energy density and higher power density in portable and transportation systems. This Master thesis research is focused on three types of imidazolium based ionic liquids and their hybrids for potential applications to EDLCs, LIBs or LICs. The electrochemical characteristics, including ionic conductivities and stability windows of the three pristine ILs and their hybrids with additions of organic solvent diethyl carbonate (DEC), or common lithium ion electrolyte (LiPF6/EC/DEC) are systematically investigated. The influences of temperature and the volumetric percentage of the IL additive on their electrochemical behaviors are discussed. Finally, these ionic liquid hybrids were examined in LIB and LIC devices to assess their impacts on energy storage performances.

Page Count


Department or Program

Department of Mechanical and Materials Engineering

Year Degree Awarded