Smartphones may soon be charged within a few seconds and last a week thanks to a bendy device smaller than a postage stamp. A new process for creating flexible ‘supercapacitors’ that store more energy and can be recharged more than 30,000 times could revolutionise the industry. Scientists reckon it will transform the way we use mobile phones, tablets, laptops, wearable tech and even electric vehicles.
Dr Nitin Choudhary, of the University of Central Florida, said: “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.” After 18 months or so a smartphone holds a charge for less and less time as the battery begins to degrade. Scientists have been studying the use of nanomaterials to improve supercapacitors that could enhance or even replace batteries in electronic devices.
But a device that held as much energy as a lithium-ion battery would have to be much, much larger. Dr Choudhary and colleagues have experimented with applying newly discovered two dimensional materials only a few atoms thick, while other researchers have tried formulations with graphene and other materials, but with limited success.
Team leader Professor Eric Jung explained: “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. “We developed a simple chemical synthesis approach so we can very nicely integrate the existing materials with the two dimensional materials.”
So his researchers made supercapacitors composed of millions of nanometre thick wires coated with shells of two dimensional materials. A highly conductive core facilitates fast electron transfer for quick charging and discharging. And uniformly coated shells of 2D materials yield high energy and power densities.
Dr Choudhary said: “For small electronic devices, our materials are surpassing the conventional ones worldwide in terms of energy density, power density and cyclic stability.” Cyclic stability is the number of times a battery can be recharged before degrading. Lithium-ion batteries, used in smartphones, can be recharged fewer than 1,500 times without significant failure while recently developed supercapacitors can be recharged a few thousand times.
But the new process yields a supercapacitor that doesn’t degrade even after it’s been recharged 30,000 times. Supercapacitors that use the new materials could be used in phones and other electronic gadgets, and electric vehicles that could benefit from sudden bursts of power and speed.
And because they are flexible, it could mean a significant advancement in wearable tech, as well.
Added Prof Jung: “It is not ready for commercialisation. But this is a proof of concept demonstration, and our studies show there are very high impacts for many technologies.”