Silicon nanowire battery holds 10 times the charge of existing ones

Stanford researchers have found a new method for battery making using Silicon nanowires. They produce 10 times the amount of electricity of existing Lithium-ion batteries by holding more electric charge compared to carbon material used now.

The electrical storage capacity of a Li-ion battery is limited by how much lithium can be held or stored in the battery’s anode, which is usually made with carbon material. Stanford researchers used silicon nanowires to replace the carbon and found that it can hold 10 times as much. The new method was developed by Yi Cui, assistant professor of materials science and engineering and his associates. A laptop that runs on battery for two hours could operate up to 20 hours without recharging, which would be a considerable advantage for many people, and less electricity is needed to recharge. Cui calls this novel method not a small improvement, but rather a revolutionary development. This research report has been published online (Dec. 16) in Nature Nanotechnology under the heading, “High-performance lithium battery anodes using silicon nanowires”. It is authored by Cui, his graduate chemistry student Candace Chan and five others. This new battery will have a wide range of applications; first it has the potential to boost many devices that currently use batteries such as iPods, mobiles, cameras, video cameras and many more. It can also be used to store electricity generated from solar panels, and it can store more charge, for longer periods of time, without wasting electricity with constant recharging. Another bit potential is for electric cars: They could potentially be driven longer distances than ever before. Silicon has a much higher capacity than carbon, but also has a drawback: The silicon in the battery swells when it absorbs positively charged lithium atoms during charging and shrinks when in use. "This expand/shrink cycle typically causes the silicon (often in the form of particles or a thin film) to pulverize, degrading the performance of the battery." Cui overcame this problem by using nanowires; the lithium is stored in a forest of tiny silicon nanowires, with a diameter of one-thousandth the thickness of a sheet of paper. These nanowires swell four times their initial size as they store lithium atoms, but unlike the regular silicon, it retains its shape without any breakdown. So, it can be used many times. Cui said they have filed a patent and they are planning to either start a company or an agreement with a battery manufacturer. He said this process can be easily translated for commercial manufacture and use. I think this is great news. We waste too much money and energy on today's inefficient batteries.