Goodbye battery, hello ultracapacitor
Batteries are increasingly being flagged as a huge enviromental problem. Especially as cell phones become disposable items, the leaching of heavy metals and toxins into the environment from batteries is a growing problem.
In what seems to be a miraculous development, researchers at MIT have devised a way to store electricity like water in a sponge. The technique involves the modification of an electronic component called an ultracapacitor, improving it to hold as much electricity in the same form factor as a conventional battery. Not only that, but they can be recharged in an instant, and they last ten years.
The LEES ultracapacitor has the capacity to overcome this energy limitation by using vertically aligned, single-wall carbon nanotubes — one thirty-thousandth the diameter of a human hair and 100,000 times as long as they are wide. How does it work? Storage capacity in an ultracapacitor is proportional to the surface area of the electrodes.
Today’s ultracapacitors use electrodes made of activated carbon, which is extremely porous and therefore has a very large surface area. However, the pores in the carbon are irregular in size and shape, which reduces efficiency. The vertically aligned nanotubes in the LEES ultracapacitor have a regular shape, and a size that is only several atomic diameters in width. The result is a significantly more effective surface area, which equates to significantly increased storage capacity.
The new nanotube-enhanced ultracapacitors could be made in any of the sizes currently available and be produced using conventional technology.
“This configuration has the potential to maintain and even improve the high performance characteristics of ultracapacitors while providing energy storage densities comparable to batteries,” Schindall said. “Nanotube-enhanced ultracapacitors would combine the long life and high power characteristics of a commercial ultracapacitor with the higher energy storage density normally available only from a chemical battery.”
Let’s hope this research pays off and we can say goodbye and good riddance to the ubuquitous and poisonous battery.
