Materials Science and Engineering Graduate Seminar

April 17, 2018
April 17, 2018
Speaker: Craig Arnold, Ph.D.
                 Princeton University  
Title: Piezoelectrochemistry in Li-ion Batteries: Coupling Mechanics and Electrochemistry
Time: Noon
Abstract: Because of their high energy densities and high working voltages, lithium-ion batteries are the most suitable energy storage choice for a variety of applications from large scale battery electric vehicles to small scale implantable medical devices.  These systems are well-known to experience both mechanical and electrochemical phenomena and in this presentation, we discuss how the evolution of internal and external mechanical stress affects the electrochemical performance over the lifetime and how the electrochemical state of the system influences its mechanical properties.  Starting with the internal stress state of the battery, we identify the dynamic nature of this quantity, fluctuating with charge/discharge and gradually increasing irreversibly over long times with electrochemical cycling. Further probing of the system behavior reveals that not only the stress state, but regions of stress localization within the cell can lead to electrochemical phenomena which further accentuate performance degradation.  Based on a detailed understanding of mechanical and electrochemical coupling, we demonstrate how it is possible using standard li-ion batteries to construct a thermodynamic process for harvesting mechanical energy at low frequencies.  Such a mechanism exhibits certain benefits over more traditional piezoelectric energy harvesting that will be discussed. 
Bio: Craig B. Arnold is a Professor of Mechanical and Aerospace Engineering at Princeton University and the director of the Princeton Institute for Science and Technology of Materials.  His research ranges from basic science to applied technology aimed at developing a deeper understanding of fundamental materials synthesis and processing with interests in energy storage systems, laser materials processing and advanced optics.  He earned his PhD. in condensed-matter physics from Harvard University, and was an NRC post-doctoral fellow prior to joining the faculty at Princeton.  Previous awards include the ONR young investigator award and the NSF Career award and more recently, his work in high-speed variable focus optics won an R&D 100 award, the Laser Focus World-OSA technology innovation award, and the SPIE PRISM award for photonics innovation.  He is a fellow of OSA and SPIE.
Hosted by: Professor Richard Lehman

For more information, please contact Sheela Sekhar at or 848.445.2159.