Battery researchers, including those at Stanford University, have been focusing for years on improving lithium batteries of multiple chemistries. While IBM tries to create the 500-mile battery based on lithium-air reactions, and ReVolt in Portland works on perfecting a long-lasting zinc-air cell, Stanford researcher Hongjie Dai and his team claim to have “developed an advanced zinc-air battery with higher catalytic activity and durability than similar batteries made with costly platinum and iridium catalysts.” The resulting battery, detailed in the May 7 online edition of the journal Nature Communications, could be the forerunner of something with greater endurance and lower cost than current efforts. Mark Schwartz, writing for Stanford, quotes Dai, a professor of chemistry at the University and lead author of the study: “There have been increasing demands for high-performance, inexpensive and safe batteries for portable electronics, electric vehicles and other energy storage applications. Metal-air batteries offer a possible low-cost solution.” Lithium-ion batteries, despite their limited energy density (energy stored per …
Making Graphene and Carbon Fibers Even Lighter and Stronger
While scientists at Columbia University have used chemical vapor deposition (CVD) to create large sheets of stronger-than-average graphene, a research team at Massachusetts Institute of Technology (MIT) has found ways to weave stronger carbon nanotubes. James Hone and Jeffrey Kysar, professors of mechanical engineering at Columbia University, learned that the enormous strength of graphene is usually achieved in only small patches. The “grain boundaries” for larger sheets were often far weaker than the theoretical strengths of which the material is capable. That strength is phenomenal. Hone explains, “It would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of Saran Wrap.” Results of their study were published in the journal Science. The paper’s lead author, Gwan-Hyoung Lee, a postdoctoral fellow in the Hone lab, says, “Our findings clearly correct the mistaken consensus that grain boundaries of graphene are weak. This is great news because graphene offers such a plethora of opportunities both for …
Two Crossings of the U. S. in Opposite Directions
While Solar Impulse prepares for a third leg of its Across America flight, two intrepid motorcyclists are on their way or preparing to depart on similar, but ground-bound traversals. Terry Hershner reported on his “Life Off the Grid” Facebook page, “On the edge of the Pacific Ocean, moments from Mexico, officially leaving the west coast at 1:40 am Friday May 31st.” By Saturday afternoon, he was well past El Paso, scurrying at the 70 mph he’s been maintaining through the trip so far, but only when he’s moving. Three incidents have brought him to a stop for varying periods. One unintentional “off-roader” near Gila Bend, Arizona tied up the eastbound lane for an hour while police removed his vehicle from the road. Outside Lourdsburg, New Mexico in the early morning, he texted, “Going ‘Zero’ mph for the last 45 minutes. A drunk driver hit the bridge and the highway patrol shut down I-10 so a life flight helicopter could land. …
Cella Packages Hydrogen in Usable Ways
Cella Energy, a UK-based energy company, announced big plans for hydrogen storage in early 2011, and is now beginning to deliver on its earlier promise. Hydrogen, as desirable as it is for use in transportation, presents many hurdles in its use. Creating an infrastructure for its distribution has been a major impediment so far, but Cella hopes to overcome that with its nanotechnology pellets that can be distributed, transported and used much like fossil-fuel liquids. Cella highlights the fact that the hydrogen is stored in low-pressure form at ambient temperatures and can be handled safely in the open air (something that can’t be said about gasoline, for instance). It benefits customers by being able to use existing distribution networks and outlets. Imagine a gas station or airport refueling truck that dispenses hydrogen in pellet form as well as the normal liquid fuels. The company’s “elevator pitch” promotes the “three minute, 300 mile rule.” We’re used to pulling into a gas …
Verticopter® Now Elytair
Oliver Garrow has been working with a convertiplane design concept since 2007, and has flown over 100 “sorties” with large scale models to test the concept and demonstrate flight characteristics. Reported here in 2010, the aircraft initially looked a bit like an annular-wing configuration with pivoting engines or electric motors for lift and propulsion. Now, in its most current version, it looks a bit more like a box wing design with pivoting propulsion. Oliver’s company has changed its name from Verticopter to Elytair. As explained in company literature, “Elytair, named with the goal to offer Elite personnel Air transportation solutions, will be offered as a design platform through selective licensing agreements, for either manned or unmanned applications.” As with the Verticopter, the Elytair can land and take off in every conceivable mode; conventional take-offs and landings (CTOL), vertical take-off and landing (VTOL) and short take-offs and vertical landings (STOVL). As with helicopters, Elytair can hover, but because it can pivot …
Solar Impulse Tries for Absolute World Distance Record
Starting with a pre-dawn blessing by a native American chief in Phoenix, Arizona and ending with a press conference in Texas, which included a charming interview between Bertrand Piccard and a young Dallas boy who would have to wait until fall to tell his elementary school mates about his inspiring meeting, Solar Impulse achieved a potential world distance record for solar-powered aircraft. Before takeoff, André Borschberg performed yoga meditations, which led next to an ecumenical moment before he climbed aboard Solar Impulse. The project’s blog noted, “What made today’s departure so unique was the presence of a Native American Medicine Man, Delmar Boni, of the San Carlos Apache Tribe. Dressed in traditional clothing with a beautiful crown of feathers partially covering his face, Delmar circled around the pilots, thumb painted yellow, while chanting a pleasant tune. “He blessed today’s pilot, André (Borschberg, co-founder and CEO of Solar Impulse), and the wings that will carry him on his journey to Texas. …
A Milestone on the Road to Dr. Cui’s 10X Battery
Seeing the Amprius web site, one would never know that some “dramatic improvements” promised in the terse announcement might mean so much in terms of true breakthroughs. Neatly centered, Amprius’ total web site is a few lines of discrete text. Amprius is a leading Lithium-Ion battery developer Amprius’s silicon technology was originally developed at Stanford University and enables dramatic improvements in the energy density and specific energy of Lithium-Ion batteries. Amprius is backed by some of the world’s leading investors, including Trident Capital, VantagePoint Venture Partners, IPV Capital, Kleiner Perkins Caufield & Byers, and Dr. Eric Schmidt. Amprius, Inc., 225 Humboldt Ct. Sunnyvale, CA 94089 But the battery manufacturer has two first-generation product offerings with volumetric energy densities of 580 Watt-hours and 600 Watt-hours per liter. Most lithium batteries fall into a range from 250-500 Wh/l., putting the new cells at the upper limit of such batteries. Both Amprius batteries are now in production and available to original equipment manufacturers, …
Navette Brettone Carries On
The April, 2013 issue of Info.Pilote magazine, a French publication, features the air-show pairing of the electric Cri-Cri E-Cristaline, powered by two Electravia GMPE 104 motors and riding atop a Broussard – what the DeHavilland Beaver might look like if it had been built in France. The great photos by Jean-Marie Urlacher are supplemented by a dynamic video showing a typical airshow lofting and separation – something that happens quickly even in slow motion. Info.Pilote has an informative table comparing the Navette Brettone (Brittany Shuttle), named for the sponsoring ferry boat operation, with the Navette Spatial, our space shuttle/Boeing 747-100 combo. While the big Boeing spans 196 feet, the Broussard is a relatively petite 45 feet. The Space Shuttle riding on the 747 is a substantial 78 feet, while the tiny Cri-Cri is a mere 16 feet across. The different airplanes’ relative weights are even more revealing. The 708,400 pound Boeing carries a 286,000 load: the 5,940 pound Broussard lofts …
Eurosport Crossover Sports Many Tricks
We’re used to seeing motorgliders which pop an engine or motor up on a tall stalk behind the cockpit, then retract it into the slim tailboom for minimum drag. Why not do the same with two electric motors on each side of the airplane, tucking them in a slender fuselage for soaring? Emails with Eurosport’s Tom Leite and perusal of the Portuguese firm’s web site and on-line brochure verified that almost everything on the Crossover motorglider is electric and retractable. Tom notes, for instance, “Our motor/props fold into the fuselage: [they are] 3-phase PMSM motors up to 40Kw at takeoff each.” In the video, see the long, spar web-like structure with lightening holes that separates the two motors as they slide into and out of the fuselage. “Our wing span is set from 9.6 to 15 meters and is electrically operated.” Tom refers to the special version that will have extendable and retractable wings, with tip segments sliding out from …
Ion Tiger Exceeds 48 Hours in Flight
Researchers at the U.S. Naval Research Laboratory flew their fuel cell powered Ion Tiger UAV for 48 hours and 1 minute on April 16-18 by using liquid hydrogen fuel in a new, NRL-developed, cryogenic fuel storage tank and delivery system. This flight shatters their previous record of 26 hours and 2 minutes set in 2012 using the same vehicle, but with gaseous hydrogen stored at 5000 psi. The airplane had flown 23 hours, 17 minutes in 2009. The 550 Watt (0.75 horsepower) fuel cell onboard the Ion Tiger has about four times the efficiency of a comparable internal combustion engine and the system provides seven times the energy in the equivalent weight of batteries. The Ion Tiger weighs approximately 37 pounds and carries a 4- to 5-pound payload.” Gerard Thevenot, who flew the English Channel on a hydrogen-powered “trike” in 2009, used about 550 grams per flight hour, with the craft’s 5-liter tank allowing about one hour flying time. …