Fast, safe and a bigger battery storage capacity are needed if the energy transition is to be successful. One advantage is that they will be able to store the excess solar and wind energy for later use. There is just one problem – the current generation of batteries have already reached their maximum capacity. The way to go is to design batteries that use other materials. Tim Alders researched one such promising material and immediately designed a versatile method to determine why materials may or may not work well in batteries. His research for his master’s in Applied Physics earned him the title of Best Graduate of the Faculty of Applied Sciences.
Tim Alders is 26 years old and has earned three masters, two in the field of physics, and one in the field of psychology. “I have always felt blessed that I find it easy to study. It really is a privilege. My parents, who did a lot of voluntary work, set the example of doing something good, and this was very motivating and I gave a lot of private lessons at secondary school. During the first year of my physics programme, I had a gnawing feeling of wanting to do something meaningful for the world. I felt perfectly comfortable in my studies, but I missed the human aspect. So after a year I started studying psychology as well (with a master’s in Economic and Consumer Psychology) and I started working part-time as an exam trainer.”
Crossroads
The balance in the two fields suited him well, but after obtaining both bachelor degrees, he was at a crossroads. What now? “While I was doing a minor in Canada, I was very impressed by the overwhelming nature there. The realisation that ‘we must be much more careful with it’ really hit me for the first time. That feeling returned strongly when I was in the bus going to the airport in Finland to return home. It was the summer after completing my first two bachelors and I had spent three weeks trekking and camping in the wilderness. I decided that I wanted to be part of the energy transition and immediately thought of improving battery storage. I had read a lot about it and I knew that there was a long way to go. The combination of the Sustainable Energy Technologies and Applied Physics masters seemed to be the best way to contribute to this.”
I decided that I wanted to be part of the energy transition and immediately thought of improving battery storage.
Tim Alders
Best Graduate of the faculty of Applied Sciences
Undiscovered possibilities
Tim came into contact with postdoc Theo Famprikis through his professor, Marnix Wagemaker. At the time, Famprikis was already doing research into the use of alternative materials in batteries to obtain bigger storage capacity. Tim explains that “Most batteries use lithium as it is very lightweight and thus ideal for relatively small batteries. But the weight of the battery is less important in batteries which you want to use to store sustainable energy at a large scale. More important requirements are to be able to store a lot of energy quickly and safely. With this in mind, there is a world of undiscovered possibilities. You can replace the materials in batteries that cause a chemical reaction. But you can also work with conductive materials – the electrolytes that move the positive particles in batteries.” Out of a mountain of options, Tim chose the Na3PnS4 electrolyte for further research. “I decided on this particular electrolyte because its base is sodium, a much cheaper metal than lithium and that is much easier to obtain. It can for example also be found in kitchen salt.”
The weight of the battery is less important in batteries which you want to use to store sustainable energy at a large scale. With this in mind, there is a world of undiscovered possibilities.
How do batteries actually work?
To better understand what exactly he is researching, Tim first explains how batteries work. “In principle, all batteries work the same way. They have a plus and a minus end and a connecting piece of metal outside the battery that ensures that the current goes to the device that you want to use. This only happens when the battery is connected as a chemical reaction then happens inside the battery which creates positively charged particles (ions) and negatively charged particles (electrons). The ions move through the electrolyte towards the plus side, and the electrons move to the plus side through the connected device. The movement of the electrons delivers a current to the device.
If the electrolyte is made of a solid material, the process is slightly different. The ions then do not move through a liquid, but through a crystal lattice. Amazingly, the movement can be faster than what is possible in a liquid. This fact is important as good conduction is one of the factors that help create faster and better battery storage.”
TU Delft student working in the battery lab.
Fast conductor
So what exactly did Tim research? “I researched which variant of Na3PnS4 – these are Na3SbS4, Na3AsS4 and Na3PS4 – moved the ions the quickest and why. One of the things I found out was that the Na3SbS4 variant does this best because the bonds in this substance with sodium are weaker than in the other variants. I also developed a simulation method which other researchers can use to broadly determine why materials in batteries do or do not conduct ions well.”
Both findings are important, but he is most proud of the simulation method that he developed. “I can help other researchers decide which materials are most suitable for the battery of the future.”
I can help other researchers decide which materials are most suitable for the battery of the future.
Tim Alders
Best Graduate of the faculty of Applied Sciences
Balance
The Board of Examiners that nominated Tim as Best Graduate at the Faculty of Applied Sciences not only praises the in-depth work that he delivered and the way in which he divided up a large problem into doable questions, but they are also impressed with his positive attitude and strong social skills. What does he himself think of being Best Graduate of his Faculty? “The last three years were heavy and intense as both my father and my mother were seriously ill. I really had to find the balance between trying to do everything in my study well, being there for my parents, and not forgetting to look after myself. The prize confirms that you do not need to forget what really is important to achieve something great.”
Future
Tim has now worked for a couple of months as a Change Officer at Stedin, a power grid company. As part of this young professional programme, he will work each six months on a new change process. “I really wanted to experience life in industry and when a friend told me about this job, I was sold. I get the chance to do what I think is important – building bridges between technology and people.” He is happy and has found his place for now. “Although I hope to work with Theo sometime in the future on designing a solid-state battery that has sodium as a active material.”
