Scientists at the University of Central Florida (UCF) have developed nanoscale supercapacitors that could endure more than 30,000 cycles without degrading.
Supercapacitors are being explored as a possible alternative to the lithium-ion batteries that power everything from smartphones to electric vehicles (EVs). Lithium batteries can require a long time to charge, tend to start degrading quickly, and often fail before reaching 1,500 cycles. Supercapacitors can be charged quickly, but one that held as much energy as a lithium-ion battery would need to be extremely large.
To address the issue, engineers are now looking to nanomaterials. The research, described in the journal ACS Nano, saw the UCF team applying newly discovered two-dimensional materials just a few atoms thick to supercapacitors. They used 2D transition-metal dichalcogenides (TMDs) integrated with an array of one-dimensional nanowires.
According to the paper’s abstract, these hybrid supercapacitors outperform previously developed stand-alone 2D TMD-based supercapacitors, with their structural robustness delivering more than 30,000 charge-discharge cycles with no drop in performance. Previous researchers have attempted similar techniques using graphene and other 2D materials, but success has been limited.
“There have been problems in the way people incorporate these two-dimensional materials into the existing systems – that’s been a bottleneck in the field,” said principal investigator Yeonwoong Jung, an assistant professor at UCF’s NanoScience Technology Centre and Materials Science & Engineering Department.
“We developed a simple chemical synthesis approach so we can very nicely integrate the existing materials with the two-dimensional materials.”
Although not yet ready for commercialisation, the technology holds promise for a wide range of electronics devices, as well as EVs that require a sudden burst of power. The materials are also flexible, giving them potential applications in wearable tech.
“For small electronic devices, our materials are surpassing the conventional ones worldwide in terms of energy density, power density and cyclic stability,” said Nitin Choudhary, a postdoctoral associate at UCF who conducted much of the research.
“If they were to replace the batteries with these supercapacitors, you could charge your mobile phone in a few seconds and you wouldn’t need to charge it again for over a week.”
I would contest the last statement, a typical 3.6Ah phone battery if charged in a few seconds would require a charging current of several hundred amps! That sounds like a potential heat dissipation issue. Unless of course the technology will work a several hundred volts in which case the charging current would be correspondingly lower. But I doubt that’s likely when the insulator is, I quote, ” just a few atoms thick”.
The only way around it is to make all wearables also charge from friction produced by us when walking etc. There’s so much energy that could be taken just from simple scrolling through facebook. That will reduce charging time needed and high current issues as well as possible high voltage issue. You must also remember that before they introduce this into mass production they’ll be looking at the best way of charging it. I’m still surprised why so many EV manufacturers don’t use solars and wind turbines in their systems? When you go at 70mph on UK motorway it would somehow charge up the battery a fair bit…