| abstract
| - Posted on 08:01, 26 February 2008 (UTC) by Tcrow777 (talk · contribs · logs · count) The future of batteries is now known, it is capacitors layered in charge-holding carbon nanotubes. Your smartphone keeps getting more advanced, but the batteries seem to lag behind, one of the biggest complaints of smartphone users is short battery life and long charge times. Ever wish your smartphone's battery could charge in a matter of seconds? The Massachusetts Institute of Technology (MIT) and Cambridge University in Britain say it's possible. They turned to the capacitor, which was invented nearly 300 years ago. Joel Schindall of MIT explained to ScienCentral News, "We made the connection that perhaps we could take an old product, a capacitor, and use a new technology, nanotechnology, to make that old product in a new way." Rechargeable and disposable batteries use chemical reactions to produce energy. Schindall told ScienCentral News, "That's an effective way to store a large amount of energy," Schindall said to ScienCentral News, "but the problem is that after many charges and discharges … the battery loses capacity to the point where the user has to discard it." Capacitors hold energy as an electric field of charged particles created by two metal electrodes. Capacitors charge faster and last longer than normal batteries. The problem is that storage capacity is proportional to the surface area of the battery's electrodes, so even today's most powerful capacitors hold about 25 times less energy than similarly sized standard chemical batteries. The researchers solved this by covering the electrodes with millions of tiny filaments called nanotubes. Each nanotube is 30,000 times thinner than a human hair. Similar to how a thick, fuzzy bath towel soaks up more water than a thin, flat bed sheet, the nanotube filaments increase the surface area of the electrodes and allow the capacitor to store more energy. Schindall said to ScienCentral News that this combines the strength of today's batteries with the longevity and speed of capacitors. "It could be recharged many, many times perhaps hundreds of thousands of times, and … it could be recharged very quickly, just in a matter of seconds rather than a matter of hours," Schindall said to ScienCentral News. This technology has broad practical possibilities, affecting any device that requires a battery. Schindall said to ScienCentral News, "Small devices such as hearing aids that could be more quickly recharged where the batteries wouldn't wear out; up to larger devices such as automobiles where you could regeneratively re-use the energy of motion and therefore improve the energy efficiency and fuel economy." Schindall said to ScienCentral News that he thinks hybrid cars would be a particularly popular application for these batteries, especially because current hybrid batteries are expensive to replace. Schindall said to ScienCentral News that he also sees the ecological benefit to these reinvented capacitors. According to the Environmental Protection Agency, more than 3 billion industrial and household batteries were sold in the United States in 1998. When these batteries are disposed, toxic chemicals like cadmium can seep into the ground. "It's better for the environment, because it allows the user to not worry about replacing his battery," Schindall said to ScienCentral News, "it can be discharged and charged hundreds of thousands of times, essentially lasting longer than the life of the equipment with which it is associated." ScienCentral News reports that Schindall and his team aren't the only ones looking back to capacitors as the future of batteries; a research group in England recently announced advances of their own. But Schindall's groups expects their prototype to be finished in the next few months, and they hope to see them on the market in less than five years. Schindall's research was featured in the May 2006 edition of Discover Magazine and presented at the 15th International Seminar on Double Layer Capacitors and Hybrid Energy Storage Devices in Deerfield Beach, Florida on December 2005. His research is funded by the Ford-MIT Consortium.
|
![[RDF Data]](/fct/images/sw-rdf-blue.png)