MAE Seminar: Materials and Architecture Perspectives for On-chip Energy Storage Power Generation
Abstract: Conventional electrochemical double-layer capacitors (EDLCs) are well-suited as power sources for devices that require large bursts of energy in short time periods. However, EDLCs suffer from low energy densities as compared to their battery counterparts, which restrict their applications in devices that require a simultaneous supply of high power and high energy. In the wake of improving the energy density of EDLCs, the concept of hybridization of lithium-ion batteries (LIBs) and EDLCs has attracted considerable attention in recent years. Such a hybrid known as a Lithium-ion capacitor (LIC) comprises a Li-ion intercalating anode and a fast-charging-discharging EDLC cathode. Although quite ideal in theory, such a system poses major challenges, most of which are a result of the mismatch between the specific capacities and power densities of the LIB and EDLC electrodes. In this talk, challenges and our recent progress on developing various on-chip energy storage and power-generation systems will be discussed. We have demonstrated that high-performance nanocomposites-enabled carbon micropillar arrays, as well as TiN-passivated porous Si, could be two promising platforms for on-chip application. In addition, a hybrid capacitor that utilizes a Li4Ti5O12 (LTO)-based anode and a graphene and carbon nanotube (G-CNT) composite-based cathode will also be highlighted.
Bio: Chunlei (Peggy) Wang is a full professor in the Mechanical and Materials Engineering Department at Florida International University. She received her M.S. (1993) and Ph.D. (1997) degrees in physics from Jilin University (China). Before joining FIU, she held various research positions at Osaka University (1995-2001) and University of California, Irvine (2001-2006). At FIU, Wang has developed a vigorous research program that integrates electrochemically active materials with device applications. Her group focuses on the development of micro and nanofabrication methods for building novel micro- and nanostructures and synthesizing nanomaterials that have unique structures and useful properties for energy and biological applications. Her research is currently supported by the National Science Foundation. Wang is a recipient of the DARPA Young Faculty Award in 2008, the FIU faculty award in research and creative activities in 2013 and the FIU Kauffman Professor Award in 2009. She was a co-founder of Carbon Microbattery Corporation (Enevate Corp), a consultant at Intel Lab (2012), and a guest scientist at Max Planck Institute (2012-2013).