Excellence in Research: Investigation of Interfacial Chemical and Ion Transport in Solid Inorganic-Polymer Electrolytes

Limited understanding ion transport at the interfaces in electrochemical systems is a major obstacle in the development of safe, reliable advanced lithium batteries with ultra-high energy density and high power-density. Such batteries are needed for the widespread electrification of transportation and storage of renewably generated electricity. Fundamental understanding of ion transport and control of interfacial reactions between a composite electrolyte and electrodes will enable engineering of new interfaces containing safer, solid polymer-based composite electrolytes.

In this project, the researchers will investigate ion transport at the boundaries of the electrolyte/electrodes as well as between the ceramic/polymer matrix. The team will utilize several different characterization tools to understand the properties of the materials. The students involved in this research project will be engaged in cutting-edge research on a topic of importance to addressing the global energy challenge.

This project will contribute to improving diversity in the STEM (Science, Technology, Engineering, and Mathematics) workforce by recruiting and retaining highly qualified students from underrepresented minority groups and engaging these students in cutting-edge research and development in energy storage technologies. The overall collaboration between Xavier University of Louisiana (XULA) and the University of Notre Dame (ND) which includes summer visits of undergraduate XULA researchers to the ND research group will enhance the students’ research experiences, promote retention of underrepresented minority students in STEM fields, and enable research not possible by either group individually.

Interfacial research is critically needed for designing new solid electrolyte systems with both high bulk ionic conductivity and that is chemically and dimensionally stable against the Li anode with cycling. Composite polymer electrolytes have flexibility necessary to withstand electrode volume changes with cycling, yet ion transport is limited between the ceramic and polymer in the bulk electrolyte and between the composite and the electrode surface.

The interfacial resistances lead to reduced bulk ionic conductivities, reduced safely achievable cycling rates, and poor Li anode performance. In this project by researchers at XULA and ND, the interfacial chemistry and ion transport within the system including composite polymer electrolytes and Li anodes will be investigated as a function of polymer type to allow for the fundamental understanding of each chemistry and polymer dynamics on interfacial properties.

These studies will test the hypotheses that nanoscale void formation between the electrolyte and anode, as well as between ceramic and polymer matrix, causes roughness and small contact area for ion transport which increases the interfacial resistance, and a lithium deficient layer at the interface leads to the formation of space-charge which also contributes to interfacial resistance.

This project is jointly funded by the Established Program to Stimulate Competitive Research (EPSCoR), and the Broadening Participation in Engineering Program.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.