Micro-supercapacitors could revolutionize the way we use batteries by increasing their lifespan and enabling extremely fast charging. Now, researchers at Chalmers University of Technology have developed a method that represents a breakthrough for how such supercapacitors can be produced.
Supercapacitors consist of two electrical conductors separated by an insulating layer. They can store electrical energy and have many positive properties compared to a normal battery, such as much more rapid charging, more efficient energy distribution, and a much greater lifespan without loss of performance, with regards to the charge and discharge cycle. When a supercapacitor is combined with a battery in an electrically powered product, the battery life can be extended many times – up to four times for commercial electric vehicles. And whether for personal electronic devices or industrial technologies, the benefits for the end consumer could be huge.
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 connected to, which is 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.
Agin Vyas, doctoral student at the Department of Microtechnology and Nanoscience at Chalmers University of Technology, 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 called 'system-on-a-chip’.
One of the most important challenges is that the minimal units need to be manufactured in such a way that they become compatible with other components in a system circuit and can easily be tailored for different areas of use.
The new paper published by Vyas demonstrates a manufacturing process in which micro-supercapacitors are integrated 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,” said Vyas.
“Our method is scalable and would involve reduced costs for the manufacturing process. It represents a great step forward in production technology and an important step toward the practical application of micro-supercapacitors in both everyday electronics and industrial applications.”