Will graphene be the material that powers the future?
Batteries are the bane of medical device design and development efforts. Heavy, inefficient and toxic, batteries are often the constraining factor in a medical product design. Form factor is often influenced largely by battery size and placement.
Now, graphene might be able to be used as a lightweight, flexible “supercapacitor” to power devices.
Discovered less than a decade ago, graphene has properties that could revolutionize many industries. Originally, it was considered as a possible replacement for silicon used in the computer industry, enabling faster processing using less power while dispating less heat. The hurdles to large-scale production of the material have not yet been overcome, though one new process – chemical vapor deposition (CVD) – has promise.
For graphene to have the characteristics necessary for it to function with the electrical properties of silicon, it needs to be produced in a crystaline form, with the crystals oriented precisely and with predictable edge geometry. The CVD process can do this. In crystaline form, graphene is also extremely strong.
But perhaps an even more promising use of graphene is as a power supply. Ric Kaner’s group at UCLA developed an easy way to produce sheets of graphene flakes. The material was made by coating a plastic substrate with water-soluble graphite oxide and then hitting it with a laser from an off-the-shelf dvd drive – a technique that should be easily scalable for industrial applications. When hit with the laser light, the material oxidizes, leaving behind a sheet of graphene. See the Super Supercapacitor video on Qmed.
In flake form, graphene is oriented randomly and lacks the edge alignment that gives the crystaline form its remarkable electrical and strength properties. However, Kaner’s group discovered that the material was able to quickly gain a charge then store it for a long period of time before releasing it – something that normal capacitors can’t do. A three-second charge was able to power an led bulb for over five minutes Kaner envisions that the technology could be applied to electric vehicles so that you could re-charge your car in a minute.
Rather than using batteries, medical devices could be powered by graphene supercapacitors. Extremely light, thin and flexible, graphene subercapacitors would free medical device design and development from the onerous restrictions of battery power. This could be very significant to the future of medicine.