High Temperature and Energy Materials Laboratory, Department of Metallurgical Engineering and Materials Science, IIT Bombay, Powai, Mumbai, India.
Presently, Professor at the Department of Metallurgical Engineering and Materials Science, IIT Bombay, Amartya Mukhopadhyay completed his Doctoral in Materials Research from the University of Oxford, UK, in 2009. He did his post-doctoral Research at Brown University, USA, for a couple of years. He is a Young Associate of the Indian National Academy of Engineering (INAE) and presently serving as the Honorary Secretary of Mumbai Chapter ofthe Indian Institute of Metals (IIM).<br /><br /> His research interests include materials for electrochemical energy storage (focusing on alkali metal-ion batteries) and engineering ceramics. Among his major accomplishments, he has been recognized by the Royal Society of Chemistry (UK) journals as one of the ‘2019 Emerging Investigators’, awarded with the 'IIT Bombay Research Dissemination Award 2018', 'INAE Young Engineer Award 2016', 'ASM-IIMNorth America Visiting Lectureship 2016', 'IIT Bombay Young Investigator Award 2014' and 'Dr. R. L. Thakur Memorial Award' by the Indian Ceramic Society in 2013. More details may be found by visiting; https://sites.google.com/site/amartya28nov/, https://www.iitb.ac.in/mems/en/prof-amartya-mukhopadhyay, http://htemlabiitb.wixsite.com/htem.
Session 2C — Symposium: “Electrochemical Energy Storage and Sustainability”
Organizers: S Sampath (IISc, Bengaluru) and K Vijayamohanan Pillai (IISER, Tirupati)
Stress-induced degradation of electrode materials in alkali metal-ion batteries View Presentation
Electrode materialsfor alkali metal-ion cells (such as Li-ion, Na-ion, K-ion battery systems) undergo a host of changes, such as phase transformations, structural transformations and dimensional changes during electrochemical insertion/removal of the corresponding alkali metal-ions; which, in turn, lead to stress development and concomitant mechanical degradation of the electrodes. Furthermore, irreversible reactions at the electrode/electrolyte interfaces also cause modifications to such interfaces, especially by way of formation of an additional layer that is commonly known as solid electrolyte interface (SEI). Such changes and degradations of the electrode materials and interfaces, which take place during electrochemical cycling, influence the electrochemical behavior and performances; in particular, the reversible capacity that can be practically obtained, the cyclic stability, cell impedance and voltage hysteresis. In fact, the above aspects turn out to be some of the major bottlenecks towards further enhancing the energy density and improving the safety aspects of the Li-ion battery system. There have been various attempts to understand the electrode stresses via post-cycling observations and/or mathematical modelling. However, evaluating and fully understanding the electro-chemo-structural-mechanical aspects via ex-situ experiments is neither truly feasible, nor reliable, because the stress states depend critically on the state-of-charge, electrochemical potential and surroundings of the concerned electrodes. Thus, in-situ experiments are needed for evaluating/understanding them more thoroughly; and eventually addressing them in a systematic manner and in comprehensive terms. In the above contexts, after a more generic introduction to the degradation/aging mechanisms in alkali metal-ion batteries, with particular emphasis on stress-induced degradations, the talk will highlight some of the important inferences gained fromour works related to real-time/operando monitoring of stress developments and phase transformations in electrode materials during electrochemical cycling. Important insights into the effects ofphase/structural transformations, presence of ‘buffer’ interlayers and SEI layer formation towards the deformation and stress development will be discussed, with reference toalloying-reaction based (Si, Sn), as well as intercalation-based (LiCoO2, graphenic carbon) electrode materials.