Micro supercapacitors could revolutionize battery technology by increasing their lifespan and enabling extremely fast charging. Manufacturers of everything from smartphones to electric cars are investing heavily in research and development. Now, researchers at Chalmers University of Technology, Sweden, are developing a method for producing such supercapacitors.
“When discussing new technologies, it is easy to forget how important the manufacturing method is so that they can actually be commercially produced and be impactful in society. Here, we have developed methods that can really work in production,” explains Agin Vyas, a doctoral student at the Department of Microtechnology and Nanoscience at Chalmers University of Technology and the lead author of the article.
Supercapacitors consist of two electrical conductors separated by an insulating layer. They can store electrical energy and have many positive properties when you compare them to a normal battery. For example, more rapid charging, more efficient energy distribution, and a much greater lifespan without loss of performance. That’s with regards to the charge and discharge cycle. When combining a supercapacitor with a battery in an electrical product, the battery life can extend many times. Up to 4 times for commercial electric vehicles. And whether for personal electronic devices or industrial technologies, the benefits for the end consumer could be huge.
“It would of course be very convenient to be able to quickly charge, for example, an electric car or not have to change or charge batteries as often as we currently do in our smartphones. But it would also represent a great environmental benefit and be much more sustainable if batteries had a longer lifespan and did not need to be recycled in complicated processes,” says Agin Vyas.
Manufacturing of superior battery technology is a big challenge
But in practice, today’s supercapacitors are too large for many applications where they could be useful. They need to be about the same size as the battery they are connecting to. That poses an obstacle to integrating them in mobile phones or electric cars. Therefore, a large part of today’s research and development of supercapacitors is about making them smaller – significantly so.
Agin Vyas and his colleagues have been working with developing ‘micro-supercapacitors. These are so small that they can fit on the system circuits which control various functions in mobile phones, computers, electric motors, and almost all electronics we use today. This solution is also ‘system-on-a-chip’.
One of the most important challenges is manufacturing the minimal units in such a way that they become compatible with other components in a system circuit. That’s, in addition, to easily tailoring them for different areas of use. The new paper demonstrates a manufacturing process in which they integrate micro-supercapacitors with the most common way of manufacturing system circuits (known as CMOS).
“We used a method known as spin coating, a cornerstone technique in many manufacturing processes. This allows us to choose different electrode materials. We also use alkylamine chains in reduced graphene oxide, to show how that leads to a higher charging and storage capacity,” explains Agin Vyas.
“Our method is scalable and would involve reduced costs for the manufacturing process. It represents a great step forward in production technology. It’s also an important step towards the practical application of micro-supercapacitors in both everyday electronics and industrial applications.”
A method has also been developed for producing micro-supercapacitors. It’s up to ten different materials in one unified manufacturing process. That means tailoring properties to suit several different end applications is easier.