Keynote Speaker
Biography
Prof. Liu Qi is currently an associate professor in the Department of Physics, City University of Hong Kong. He obtained his Ph.D from Purdue University in 2014. Before joining CityU, he worked as a postdoctoral fellow at Argonne National Laboratory. His current research interests focus on the structure-property-studies of functional materials via multiple neutron- and synchrotron-based techniques. His broad research activities include the design and synthesis of novel energy storage materials, phase transition mechanism and neutron-/synchrotron physics. Currently, Dr. LIU authored over 130 peer reviewed journal papers and over 20 conference papers. He has a citation of >10,000 and H-index of 53.
Lithium-ion Battery Cathodes: From Cobalt-rich to Cobalt-free
Qi LIU
Abstract
Knowledge of atomic interactions with high energy photons or particles opened up a window to the microscopic structures of materials. In particular, X-rays and neutrons interact with electrons and nuclei of atoms in different ways, which enables their complementary scattering, spectroscopic, and imaging capabilities for structural characterizations. Over the past few decades, techniques based on X-ray and neutron interactions, capable of being time resolved and combined, have been well developed for encoding structures in various length, elemental and temporal levels, and, in turn, have ignited breakthroughs in the field of battery science and engineering. In this talk, we will firstly reviewed the advanced X-ray and neutron techniques for studying secondary rechargeable batteries such as lithium-ion batteries, sodium-ion batteries and et al. For each of the techniques, with a brief description of the theory on account of characterizing principles is given (i.e., scattering, excitation, and emission), followed by an introduction of operando methodologies including instruments, setups, and cell designs employed in synchrotron and neutron beamlines. Finally, a few practical examples are presented to demonstrate the applicability of these techniques in studying lithium/sodium ion batteries, with a particular emphasis on each of their structural sensitivities at various time, elemental, and length levels.