A new process for creating flexible supercapacitors that can store more energy has been developed by a team from the University of Central Florida‘s NanoScience Technology Center. The supercapacitors be recharged more than 30,000 times before they start degrading. The innovative method from UCF could eventually transform technology ranging from electric vehicles to mobile phones.
Nitin Choudhary explained that if batteries were to be replaced with these supercapacitors, your mobile phone could be charged in a few seconds and it wouldn’t need to be charged again for more than a week.
Anyone with a smartphone knows that after approximately 18 months the battery begins to degrade and holds a charge for less and less time.
Researchers have been studying ways to improve supercapacitors that could enhance or even eventually replace batteries in electronic devices by using nanomaterials. It’s a challenging problem as a supercapacitor that is able to hold as much energy as a lithium ion battery would have to be an order of magnitude larger.
The UCF team has experimented by applying a few atoms thick layer of newly discovered two-dimensional materials to supercapacitors. Other researchers have had limited success by trying formulations with graphene and other two-dimensional materials.
Yeonwoong “Eric” Jung, an assistant professor with joint appointments to the Nano Science Technology Center and the Materials Science & Engineering Department, and principal investigator explained that a bottleneck in the field has been the way people incorporate these two-dimensional materials into the existing systems. The team from UCF have managed to integrate the existing materials with the two-dimensional materials through a simple chemical synthesis approach they have developed.
The supercapacitors developed by Jung’s team is composed of millions of wires that are nanometer-thick and coated with shells of two-dimensional materials. Fast electron transfer for fast charging and discharging is facilitated by the highly conductive core, while the shells uniformly coated with two-dimensional materials yield high power and energy densities.
It was already known that two-dimensional materials hold great promise for energy storage applications. There was however no way to realize that potential until the UCF team developed the process for integrating those materials.
Choudhary adds that their materials surpass the conventional ones used for small electronic devices worldwide, both in terms of power and energy density, as well as cyclic stability.
Cyclic stability determines how many times the charge; drain; recharge cycle can be performed before beginning to degrade. A lithium ion battery can typically be recharged less than 1,500 times before failing significantly, as opposed to the recent formulations of supercapacitors with two-dimensional materials that can be recharged a few thousand times before degradation.
By using the new process created at UCF, a supercapacitor that doesn’t degrade even after it’s been recharged 30,000 times can be manufactured.
Supercapacitors that use the new materials have a wide range of potential applications that could benefit from sudden bursts of power and speed, including electric vehicles, and phones and other electronic gadgets. As the supercapacitors are flexible, wearable tech could advance significantly as well.
Jung is of the opinion that this proof of concept demonstration shows that there are very high impacts for many technologies, but cautions that the technology is not yet ready for commercialization.
The full study was published recently in the academic journal ACS Nano.