Lunedì, 5 settembre 2022

Lithium-ion batteries, interview with Prof. Cyrus Zamani

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Energy storage plays a key role in the transition to renewable sources of electricity, wind and solar firstly. Aided by fossil fuel-driven problems, such as global warming, the demand is growing. But managing energy from renewable resources requires efficient storage. The most promising systems developed for this purpose right now are the lithium-ion batteries. This is the same technology that powers our laptops, mobile phones and electric vehicles.
Due to their versatility and falling costs, their use also in the field of renewable energy is expected to increase over the coming years. Generally, energy from renewable resources such as solar and wind is intermittent in character. Luckily, batteries can store surplus it and distribute it when needed. 
This topic was the focus of the PhD course held in August by Prof. Cyrus Zamani, of the University of Tehran (College of Engineering / Faculty of Metallurgy and Materials Engineering), during his period as visiting professor at the Department of Industrial Engineering at the University of Trento. 
For him, last month was also an opportunity to pursue his research on novel materials for Li-ion batteries in collaboration with the Materials section. 
We seized the moment and asked him a few questions about the lithium-ion batteries and his experience in Trento. 

Prof. Cyrus Zamani (left) and Prof. Stefano Gialanella (right).

First of all, how did the collaboration with the university begin?
The collaboration between the two universities started several years ago, thanks to some colleagues, on the occasion of UFGNSM conferences held in both Trento and Tehran. Personally, my request to be able to collaborate with the Department of Industrial Engineering goes back to 2019. That year was my first experience in Trento, a city I like very much. 

Moving on to lithium-ion batteries, why are they so important?
Energy is a huge issue in modern life. Everything needs the energy to operate, and worldwide a lot of research is done around this topic in various facets. In this Department, for example, people are working mainly on materials characterization. We understand the importance of what each other is doing because energy will be more and more crucial for the future of societies worldwide. Lithium-ion batteries are, for now, the most effective energy storage medium. These are the same batteries that run our electronic devices. In this context, lithium-ion batteries are the answer to the intermittency problem of renewables, like wind and solar, because they respond faster than other technologies. Energy is stored in the battery and released only when required, in small or large quantities, and for different uses.

What are their characteristics?
A lithium-ion battery is based on an electrochemical system characterized by movement of electrons and ions. Specifically, lithium atoms, separated from their electrons, move from the anode and pass through the electrolyte until they reach the cathode, where they recombine with their electrons. So, electrochemical energy is converted into electronic energy when used. This makes it possible to recharge these batteries indefinitely. This is an essential point because the old generation batteries (so-called primary type) were not rechargeable, and throwing them after just one use was necessary. Therefore, new batteries (secondary type) are now suitable for the environment, of course, and offer the possibility to recycle them, which many companies around the world are already doing.

Do these types of batteries also have disadvantages?
Yes, they do as all devices. They contain some chemical materials inside and have chemical reactions. Sometimes they may lead to CO2 emissions. This is awful for nature. But advanced batteries have control mechanisms so that batteries do not work anymore, and the impact on nature is lower.

In terms of research, what are you studying?
At the University of Tehran, researchers are working on different aspects, such as the synthesizing (nano-)materials, their characterization, and the fabrication of batteries. So, we cover all routes up to the final use. 
The collaboration with the University of Trento is essential because there is an excellent material characterization expertise here at Unitn. And one of the things we are doing is preparing new material for advanced testing and seeing if the structural properties are ok.
That is why I express my gratitude to the University of Trento, especially to Prof. Deflorian and Prof. Gialanella. Also, I would like to thank Prof. Sorarù, Prof. Fedel, Dr. Biesuz and all their students for their cooperation.