The Painted Battery

Dean Sigler Uncategorized Leave a Comment

Dr. Yi Cui, assistant professor of materials science and engineering at Stanford University, is a battery scientist extraordinaire, and a presenter at last April’s Third Annual Electric Aircraft Symposium. His paper was well received, one in which he discussed how breakthroughs in his lab could lead to an 80-percent improvement in battery capacity for the same weight as current units. He has topped himself with an extraordinary approach to manufacturing batteries. Imagine painting an ordinary piece of paper with a coating of carbon nanotubes and silver nanowires, and ending up with a very thin battery or supercapacitor. This video, courtesy of Stanford University, shows that process, and includes Dr. Cui lighting an LED with a small square of paper. He and his …

Largest-Battery Powered Airplane Takes Flight

Dean Sigler Uncategorized Leave a Comment

Two weeks ahead of the 106th anniversary of controlled powered flight by the Wright Brothers, the Solar Impulse, HB-SIA broke its earthly bounds and flew 350 meters (about a quarter mile) at a height of about one meter.  Because the airplane does not yet have its solar panels mounted, the flight was made on battery power. Graphic © Solar Impulse/EPFL Claudio Leonardi The project’s press release leaves no doubt as to the importance, and the thrill, of the flight. “The results of the ground tests conducted these last few weeks to verify numerous parameters (the prototype’s controllability, acceleration, braking paths and, engine power) had been overwhelming positive, thereby leading the team to give the go-ahead to Markus Scherdel, the test pilot, to take the …

Isn’t It Ionic?

Dean Sigler Uncategorized Leave a Comment

Only a few months after the first heavier-than-air hydrogen-fueled crossing of the English Channel (See Man of La Manche, October 29), the Naval Research Laboratory flew its hydrogen fuel cell-powered Ion Tiger for an endurance record of 26 hours and one minute.  The flight took place on November 16th through November 17th. The Navy press release claims, “Fuel cells create an electrical current when they convert hydrogen and oxygen into water and heat.  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 …

Powerful Pancakes

Dean Sigler Uncategorized 1 Comment

AST, Automation Source Technologies, has a line of compact “pancake” motors that are of interest to those designing electric aircraft. Their CDS Series have power outputs ranging up to 21 kW, efficiencies up to 93.2 percent, and weights of no more than 21 kg. The CDS 150, largest in the line, can be either water or air-cooled, handles inputs from 24 to 96 Volts DC, and operates at 1,000 to 6,000 rpm. High torque peaks, and a three to four times overload capacity might make this eight-pole series worthy of consideration.  

Sanyo Starting Mass Production of EV Batteries

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Sanyo Electric Co., Ltd.  has announced that mass production of its EVB-101 battery package will begin in 2010.  This compact package – 366 × 213 × 66 mm – or 14.4 x 8.39 x 2.60 inches, wraps a group of 18650-size computer batteries in a water-resistant aluminum housing, complete with a standard communication plug for battery management and monitoring.  The 14 in series, six in parallel package stores 10.8 Amp hours of energy and weighs about seven kilograms (15.4 pounds).  It has a maximum discharge current of 120 Amps and a continuous output of 35 Amps. The batteries got a good workout in Yokohama Rubber’s E-V Buggy at Pike’s Peak on July 19, posting the second best time by an electric …

A Tale of Three Pauls

Dean Sigler Uncategorized 3 Comments

Dr. Paul Robertson lectures at Cambridge University’s Engineering Department, and Paul Dewhurst serves as Director and Chief Flying Instructor at Flylight Airsports, Ltd.  The two Pauls made simultaneous takeoffs March 1, 2009 in Britain’s first two electric aircraft.   A third Paul, Welsh by name, acted as certification engineer for the effort. Dr. Robertson took to the skies in a Dragonfly hang glider powered by a Geiger/Eck 10kW motor/controller/propeller combination, while Dewhurst became skyborne in a Lazair ultralight propelled by a pair of Plettenberg Predator 12 kW (peak output) model airplane motors.  This testbed in particular reflects Dr. Roberton’s studies toward the constuction of a sub-115 kg electric twin called Hummingbird.  His PowerPoint presentation shows the mathematics of powering such a craft on …

A Great Year and Gala Day for Yuneec

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 Last year, we knew Yuneec for its tidy power package for paramotors, the 10 kW EPac.  We were awaiting developments on the EP200, a twin-motored, single-place ultralight that looked as though it would be powered by two EPac units.  Springtime, 2009 brought the news that a two-seater was under development, and summer brought surprise after surprise.  The 40 kW (54 horsepower) E430 made its first flights on June 12, 2009, followed by further testing on June 20.  Test pilot Sun Xun managed two flights of 15 minutes, achieving a top speed of 150 kilometers per hour (93 mph) a climb rate of 7 meters per second (1,377 feet per minute), and a maximum altitude of 300 meters (960 feet).  Sun …

A Smart Electrical System for GA

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Dr. Seeley made this available to Green Flight Challenge competitors. As a follow-on to your ideas for simplifying pilot licenses that I presented at Electric Aircraft Symposium III: Here is a link to a very encouraging development debuted at Sun & Fun: A comprehensive, integrated, smart electrical system for GA from Marc Ausman at Vertical Power Corporation ($1500 – $12,000). This looks like a very helpful reducer of pilot workload to help make flying simpler. The more up-scale versions offer redundancy and this technology should save weight and free up panel space as well. Also, the array of COTS eCFI/flight control options from MGL Avionics is very impressive too. Sure wish I had time to build a homebuilt aircraft with …

Solar Impulse Rollout and All Motors Running

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November 6, 2009, Solar Impulse left its hangar and Markus Scherdel, the project’s test pilot, ran all four motors on the giant craft.  This marks the beginning of ground testing for HB-SIA.  “With its engines running at full power, it gave the impression of wanting to get off the ground straightaway …but it won’t be long now before we release the brakes and let it roll its first few meters,” said André Borschberg, co- founder of Solar Impulse.  The four motors achieved full power at 400 rpm. Bertrand Picard, the originator of the project, was equally enthusiastic. “For the whole team, the impression of seeing it completely assembled, majestically reigning over the Dübendorf tarmac was very intense!  We just can’t …

Ready to Launch

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LaunchPoint Technologies, Inc. announces the highest power to weight ratio of any known electric motor – seven horsepower for 1.4 pounds (635 grams) or five pounds per horsepower.  As a comparison, the tiny Neutrino outrunner by Steve Neu of Neumotors weighs 14 grams and puts out 125 watts, peak.  That would add up to 784 grams at 7 horsepower if that motor were scaled up to match the output of the LaunchPoint unit.  The LaunchPoint motor is not only lightweight, but surprisingly small, scaling only six inches in diameter and one inch in thickness. It is composed of a great deal of carbon fiber in its plate-like structure. Behind this astonishing power output is the use of a Halbach array, “an arrangement …