Interfacial studies of lithium metal with a composite polymer electrolyte
Dr. Lamartine Meda, Xavier University
11:00 a.m., December 5, 2023 | Carey Auditorium, 107 Hesburgh Library
Composite polymer electrolytes (CPEs) are a viable alternative to replace flammable and potentially hazardous liquid electrolytes as lithium-ion conductors to realize safe solid-state batteries with high energy density.
In this study, the CPE is a cross-linked polymer network made of poly(propylene carbonate), poly(ethylene glycol) diacrylate, poly(ethylene glycol) methyl ether acrylate, lithium bis(trifluoromethane)sulfonimide.
Electrochemical impedance spectroscopy was used to study the interface of the cell after plating and stripping Li and ageing, and the results demonstrated a stable and highly conducting interface. The CPE was highly flexible and showed no degradation over 800 hours of cycling at different current densities. Moreover, studies performed under open circuit potential confirmed plating and stripping results. The ionic conductivity for the CPE at 40 °C was ~ 6.4 x 10-4 S cm-1. An all-solid-state full cell was fabricated with a composite cathode (LiNi0.5Mn1.5O4 (LNMO), super-p carbon black, and CPE), solid electrolyte, and Li metal (LNMO|CPE|Li), which proved the effectiveness of the electrolyte. The CPE suppressed the growth of dendritic Li from the anode surface while simultaneously improving the interfacial stability.
Dr. Lamartine Meda earned a B.S. in chemistry from Salem State University in 1992 and a Ph.D. in materials inorganic chemistry from Northeastern University, Boston, MA, in 1998. He was a NASA postdoctoral fellow at the National High Magnetic Field Laboratory (NHMFL) and the FAMU-FSU College of Engineering under Professor Hamid Garmestani from 1999 to 2001. After that, he spent four years as a Senior Research Scientist at Excellatron, Atlanta, GA. There, he worked on the R&D of solid-state electrolytes for thin-film batteries using plasma-enhanced chemical vapor deposition (PECVD). He was awarded two patents for his inventions of the PECVD deposition of LiPON solid electrolyte.
He joined the chemistry faculty at Xavier University of Louisiana in 2008 after spending two years as a visiting assistant professor of chemistry at Auburn University. Dr. Meda is the director and principal investigator of the Materials and Interfaces Center for High Energy Storage and Sensing (MICHESS), with over 20 years of experience in energy storage. He was named the Bellsouth Endowed Professor of Chemistry and Materials Chemistry at the Xavier University of Louisiana in 2021. His primary research interest is on composite materials and high energy density solid-state lithium batteries.