by Jonathan Schoenfeld, Live Free Natural | see original article
Silicon nanotube batteries are considered the Holy Grail to technology enthusiasts. Silicon nanotubes are able to store hydrogen and can potentially be used as a metal fuel that resembles coal but without the CO2. Perhaps its most intriguing application that has everyone raving is how it applies to batteries.
One silicon atom has the ability to bond to four lithium ions, while it takes six carbon atoms to bond to a single lithium ion making silicon a far more suitable anode for lithium batteries than carbon. With silicon nanotube anodes, batteries could be made smaller while increasing power and longevity. Image credit to Flickr.com
Extreme tech explains just how superior silicon is to carbon for battery use:
“Currently, almost every lithium-ion battery uses a graphite (carbon) anode, which has a specific capacity of 400 mAh per gram, which means the anode has to be relatively large to store a decent amount of power. Yi Cui’s team, however, has successfully built a double-walled silicon nanotube anode that has a capacity of around 4,000 mAh per gram. In other words, this anode is an important precursor to lithium-ion batteries with 10 times their current capacity.”
Yi Cui, professor at Stanford University and considered the battery guru, developed double walled silicon nanotubes which can survive 6000 charge/discharge cycles and still maintain an 85% charge. The only issue now is developing a simplified four step method to developing nanotubes. Amprius just received an additional $30 million on top of its $25 million for developing this next generation battery. Amprius hopes to have a working model for automobile applications by next year.
“Next year, the company will get into the electrical transportation market, Sun added. That’s an application where the key performance metric isn’t watt-hours per liter, but watt-hours per kilogram, a reflection of the key importance of battery weight for vehicles.”
Amprius isn’t the only company focused on silicon anode development. Battery and component manufactures 3M, panasonic, and LG Chem have all made plans to bring these types of batteries to the marketplace. Some companies are even attempting to provide a better product than what Amprius is developing. Oak Ridge National Laboratory claims that their use of copper nanowire to strengthen silicon nanotubes can offer more durability and faster charging than just silicon nanotubes. Whatever it comes to, the next generation batteries are sure to revolutionize.