Abstract:
Rechargeable energy storage devices, such as Li-ion batteries and supercapacitors, are at the heart of widely used electrical devices such as smartphones and electric vehicles. As the energy density of these devices steadily increases, safety concerns are growing. Toxic and/or explosive gases may evolve as a result of decomposition of the electrolyte and/or the electrode material and these gases are generally trapped in the cell. However, the characterization of assembled cells has been limited to measuring externally accessible parameters such as voltage, current and temperature. Thus, there was little information about the composition of the evolved gases and the mechanism of gas evolution.
This talk introduces a new way to measure the evolved gases from commercially available cells using Raman spectroscopy. This is made possible by designing external Raman cells for supercapacitors and Li-ion battery cells. Using those cells, we were able to identify evolved gas species and to track the partial pressures of individual gases in real time. We will also talk about the effects of harsh conditions such as high voltage and temperature on the gas evolution and electrochemical performance of the cells.Brief Bio:
Prof. Son is an applied scientist and electrical engineer. His earlier work focused on Raman spectroscopy of carbon nanotubes and graphene. His main interest now is to expand Raman spectroscopy to more practical applications such as battery safety and stem cell research.
Brief Bio:
Education
2003, BS, Electrical Engineering and Computer Science, MIT
2004, BS, Physics, MIT
2004, MEng, Electrical Engineering and Computer Science, MIT
2008, Ph.D, Electrical Engineering and Computer Science, MIT
Professional Experience
2008-2011 Research staff member, Samsung Advanced Institute of Technology
2012-2015 Assistant Professor, School of Integrative Engineering, Chung-Ang
University, Republic of Korea
2016-2017 Associate Professor, School of Integrative Engineering, Chung-Ang
University, Republic of Korea