Behang University Makes a Better Battery

Lithium-sulfur batteries display winning qualities, such as low production cost, environmental friendliness, and high energy density.  Researchers usually give up, or look elsewhere, when the materials’ poor cycle life and loss of active materials on both anode and cathode show up.

Researchers at Beihang University in Beijing report developing “a new Li-sulfur battery using honeycomb-like sulfur copolymer uniformly distributed onto 3D graphene (3D cpS-G) networks for a cathode material and a 3D lithiated Si-G network as anode.”  They report “a high reversible capacity of 620 milli-Amp hours per gram, [and an] ultrahigh energy density of 1,147 Watt-hours per kilogram (based on the total mass of cathode and anode), good high-rate capability and excellent cycle performance over 500 cycles (0.028% capacity loss per cycle).”

Structure and performance of Beihang battery

Structure and performance of Beihang battery

The materials used in the cathode and anode presented challenges.  The “inherent insulation of sulfur” on the cathode and the high solubility of polysulfide intermediates cause an inability of the active materials to respond to one another, and the conversion of sulfur into less reactive materials lowers output and cycle life.

Researchers tried a series of logical steps, including embedding sulfur into activated carbons, and into carbons with pores of varying sizes – everything from macroporous, mesoporous, and smallest of all – microporous carbon structures.  This improved electric conductivity and slowed loss of active materials, but still limited the amount of sulfur and polysulfides that could be carried on the cathode materials.

Coating the cathode with sulfur copolymer “has shown good inhibition of polysulfide dissolution, but needs improved electric conductivity.”  So, all solutions bring with them an accompanying problem, even with a net gain in output.

Anodes have another set of initial issues, because the lithium metal reacts with many electrolytes and forms dendrites during charge-discharge cycles, shortening the battery’s life and causing severe safety issues.  Alloy-type anodes with similar voltage plateaus to lithium include silicon nanowire and lithiated Si/SiOx nanospheres.

Perhaps because of the many ways in which lithium and silicon can be combined with graphene and myriad other materials and electrolytes, the authors of the paper on this research conclude this way:

“Thus, a new type of silicon-sulfur battery built from silicon-based anode and sulfur-based cathode is becoming one of next-generation Li-S batteries to overcome their severe cyclability and safety problems. However, the researches of emerging silicon-sulfur battery including the configurations, design and fabrication of appropriate and mutual matching anodes and cathodes are still in the infancy.”

Bin Li, Songmei Li, Jingjing Xu and Shubin Yang published their findings in the Royal Society of Chemistry’s (RSC’s) journal Energy & Environmental Science, under the title “A new configured lithiated silicon-sulfur battery built on 3D graphene with superior electrochemical performances.”

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300 Horsepower, 737 Foot-Pounds of Torque

Extra 330Ls have a long nose, usually cowling a Lycoming IO-540 or -580.  The 330 EL, though, houses 14 battery packs of 18.6 kilowatt-hours each (according to InfoAvion, an Argentinian publication), all to allow the Siemens D-SP260 to flex its 300 horsepower muscle and demonstrate what 1,000 Newton-meters (737 foot-pounds) of torque can do for vertical rolls.

Flying Magazine thought that its display at AERO Friedrichshafen in Germany could be a harbinger of the future of emission-free airshow performances.”

Siemens intends to use the 330 EL for flight test and optimization of a electric propulsion system based on the 50 kilogram (110 pound) motor on display.  Even the large battery array will give only about 15 to 20 minutes of wide-open airshow power, enough for a great routine, lacking only the airshow noise.

Batteries under glass highlight Extra 330 EL, sure to provide a little extra in performance

Batteries under glass highlight Extra 330 EL, sure to provide a little extra in performance

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The Next Round of X-Planes

In your editor’s childhood and youth, X-Planes were all premised on speed, Chuck Yeager breaking the sound barrier in 1947 in the Bell X-1 when your editor was five years old (do the math). Movies that filled screens in those days featured test pilots as steely-jawed, fearless protagonists beating back the awesome forces in the sky. Frequent news stories and breathlessly narrated newsreels, and later television news captured the imagination with items about going higher, faster, and farther.

NASA is bringing back the X-plane, but emphasizing quiet, efficient, clean and practical goals. NASA’s own description of the programs shows a turn toward green aviation in our future. “Goals include showcasing how airliners can burn half the fuel and generate 75 percent less pollution during each flight as compared to now, while also being much quieter than today’s jets – perhaps even when flying supersonic.” We still feel the need for speed, but responsibly.

While the X-1 was a product of the slide rule, as were most air and space craft up through the SR-71 Blackbird and Apollo rockets, modern design relies on a three-legged stool of advanced technology. Computational power provided by supercomputers, experimental methods including precise wind tunnel measurements, and actual test flying comprise the three legs of the current X Plane program.

Results will be exciting based on demonstrations of materials, structures, aerodynamics, noise reduction and powerplants over the last six years – even including coatings that prevent bug residue buildup on wings – something about which sailplane pilots can testify. Many have been reported in the blog. These technologies could save the airline industry $255 billion over the first 25 years of their adoption.

Jaiwon Shin, associate administrator for NASA’s Aeronautics Research Mission Directorate, explains, “We’re at the right place, at the right time, with the right technologies. The full potential of these technologies can’t be realized in the tube-and-wing shape of today’s aircraft. We need the X-planes to prove, in an undeniable way, how that tech can make aviation more Earth friendly, reduce delays and maintain safety for the flying public, and support an industry that’s critical to our nation’s economic vitality.”

Programs such as LEAPTech, Boeing’s SUGAR Volt project (going on for over four years now based on the age of the video), and other existing approaches are stepping stones to the clean, green future envisioned in the latest NASA programs. Airbus in Europe, assisted by academic and governmental entities, will provide competition and incentive for American manufacturers to keep pace. None of us ever had an opportunity to share a cockpit with Yeager or Scott Crossfield, but we may be going on supersonic trans-oceanic flights in a decade or so, brought to us in the spirit of those pioneers who led before.

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At 11:44 PDT, April 22, Solar Impulse 2, expertly piloted by Bertrand Piccard through tricky winds above Moffett Airfield, made its second landing in the United State, almost three  years after Solar Impulse 1 had left on its flight eastward* and just in time to close out Earth Day.

SI2 UN Cartoon

 

HB-SIA (Solar Impulse 1) made its trip across America in six hops, none lasting more than 21 hours and 22 minutes.  HB-SIB (Solar Impulse 2) flew six hops between Abu Dhabi and Nanjing, China emulating the stages of the American crossing in distance and duration.  Things reached record-setting levels after that.  The 44-hour trip from Nanjing to Nagoya, Japan gave pilot Andre’ Borschberg a real workout, followed by his record-setting 117-hour epic voyage from Nagoya to Kalaeloa, Hawaii.  Fellow pilot Bertrand Piccard finished the trans-pacific flights with a 62-hour flight to San Francisco.

The pilots could not do this without a large ground crew, seemingly perpetually busy with preparations, maintenance, and in the case of the fading batteries, repair and testing.  In the meantime, they transport, inflate, and assemble the air-filled hangar that goes everywhere HB-SIB does.

As the team prepared to welcome Bertrand to the Bay Area, he took time to fly over all the scenic highlights, giving the populace ample photo opportunities.

In their synopsis of the flight, Solar Impulse includes the wonderful conversation between Bertrand and United Nations Secretary General Ban Ki-moon.  They shared their thoughts on the technology involved and how well it fits with the 175 nations signing the accords made at COP21 in Paris last year.  Doris Leuthard, Vice President of Switzerland, the project’s home country, had an amiable talk with Bertrand, including a strong message: “Clean technology is the future. I think it’s the most inspiring project since the flight to the moon. But with solar energy and renewable energy, what we need is proof that it is possible to make a change.”  The Secretary General closed with a near blessing.  “Thank you for your leadership and inspiration. I wish you a smooth flight. You are leading us all into an exciting new era.”

We, too, wish the people at Solar Impulse continued sunshine and a clear path back to Abu Dhabi.

*As a note of national pride, Eric Raymond flew his home-made Sunseeker 1 across the U. S. in 1990, taking 21 hops to go from San Diego to Kitty Hawk, North Carolina. 

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Thanks to Richard Glassock, we have news of the first electric airplane to fly in Hungary.  The Magnus eFusion made its maiden flight at the Matkópuszta airfield in Kecskemet, Hungary on April 11.

A two-seat, side-by-side, low-wing monoplane, eFusion is an all-composite craft with fixed tricycle gear.  Its 410 kilogram empty weight includes batteries and a ballistic recovery system. With a maximum takeoff weight of 600 kilograms, the airplane normally flies with a Rotax 912 or UL Power 260 iSA, both four-cylinder, four-stroke units meant for the Light Sport Aircraft market.

Peter Besenyei of Hungary performs during the training for the third stage of the Red Bull Air Race World Championship in Putrajaya, Malaysia on May 16, 2014. // Samo Vidic/Red Bull Content Pool // P-20140516-00025 // Usage for editorial use only // Please go to www.redbullcontentpool.com for further information. //

Peter Besenyei of Hungary performs in the Magnus (formerly Corvus) 540 during the training for the third stage of the Red Bull Air Race World Championship in Putrajaya, Malaysia on May 16, 2014

A fusion of the Corvus Racer 540, a high performance aerobatic aircraft flown in the Red Bull Air Races and the Corvus Phantom, a Light Sport Aircraft, the Magnus Fusion series of aircraft sport a symmetrical, fully-aerobatic wing (6+/3- G, not the 10G wing of the racer), a titanium firewall, chromoly tube center section (described as an “integrated chrome molybdenum central console”) and ballistic aircraft retrieval parachute.  The airplane may seem wildly over-designed for an LSA, but it performs nicely on engines smaller than the Lycoming AEIO-540 6-cylinder, air-cooled, 325 hp (242 kW) unit in the racer, and its clean design lends itself well to electric power.

Verical fin and rudder display electron representing eFusion power

Verical fin and rudder display electron representing eFusion power

Which is what the eFusion is all about.  Siemens, with its “safe and robust battery system” and optimized electric propulsion system intended for use in the “cost-sensitive segments of Very Light, Light Sport and Ultra Light aircraft,” sees aircraft such as the eFusion excellent testbeds for the Siemens systems.  And imagine having the only electric LSA on the block that can do snap rolls with aplomb.

Frank Anton, head of eAircraft at Siemens, is happy for the chance to test his company’s wares.  “The maiden flight of the eFusion is another important milestone in electric aviation. The aircraft will serve as a flying test bed for our further battery system optimization.”  A cooperative effort between a team from the Hungarian subsidiary of Siemens in Budapest and the German colleagues at Siemens headquarters, eFusion might end up bottoms up frequently.

Siemens motor and batteries being installed in eFusion

Siemens motor and batteries being installed in eFusion

eFusion’s aerobatic capabilities will allow for unusual attitudes among student pilots.  Imre Katona, CEO of Magnus Aircraft Corporation says, “Magnus gave the eFusion aerobatic capability, so it can serve for upset recovery training for airliner pilots.”. eFusion’s low operating costs will allow upset recovery training in an environmentally friendly manner while exposing more pilots to the benefits of such training – usually performed in larger, more expensive craft.

As distribution of this neat little machine grows, we may all have the opportunity to take a (literal) spin in eFusion.

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Bob Elliott of the comedy team Bob and Ray died February 3, reminding your editor of one of the many routines Elliott and Ray Goulding performed on live radio.  It involved an inventor who had perfected a solar panel that could run the lights in your house all day, but couldn’t keep them going at night when they were really needed.  That was over 50 years ago, and investigators at the Pacific Northwest National Laboratory, Argonne National Laboratory, SuperSTEM, and the University of Oxford have come up with a possible solution to Bob and Ray’s quandary.

The interfaces between the two oxides (represented in this idealized, atomically abrupt model by the yellow and purple bands) create an electric field. The field separates electrons (silver) excited by sunlight (gold), which could be used to catalyze hydrogen fuel production.

The interfaces between the two oxides (represented in this idealized, atomically abrupt model by the yellow and purple bands) create an electric field. The field separates electrons (silver) excited by sunlight (gold), which could be used to catalyze hydrogen fuel production.

Combining two oxides, one containing strontium and titanium (SrTiO3) and the other lanthanum and chromium (LaCrO3), they came up with a material that uses the interface between the two oxides to absorb visible light and produce electrons (negative charges) and holes (positive charges), which might be “useful for catalyzing reactions, such as producing hydrogen fuel.”

The oxides have to be kept apart, though, because otherwise, “they will quickly annihilate one another without doing anything useful,” somewhat like a Hollywood marriage.  The international team cleverly synthesized the material as a series of alternating layers with a built-in electric field that separates the excited electrons and holes.  This strategy makes the materials an excellent catalyst.

A visual representation of this interaction might resemble a moire pattern, but possibly only to your editor.

The Blue Square art animation black and white digital art

By controlling the interfaces to have either a positive or negative charge, the resulting electric fields can interact with electrons and holes excited by solar energy, driving electrons to the surface, where they interact with water molecules, break their bonds and produce hydrogen.

Bob and Ray would be proud.  Researchers report, “This material opens up new scientific frontiers to solve a persistent energy challenge: storing solar energy for later use. Fuel cells capable of running on hydrogen fuel created by solar energy could allow people to heat their homes and run their computers on solar energy even in the dark of night.”  Or fly their solar-powered airplanes anywhere at any time.

Researchers are exploring the properties of these superlattices using cutting-edge X-ray measurements at synchrotrons around the world and using other advanced microscopy techniques to look at the chemical makeup of the interfaces.

As one would guess, this type of research requires heavy hitters in intellectual and fiscal terms.  Participants included the Linus Pauling Distinguished Post-doctoral Fellowship at Pacific Northwest National Laboratory (PNNL Laboratory Directed Research and Development, the U.S. Department of Energy (DOE), Office of Science,Office of Basic Energy Sciences (BES), Division of Materials Sciences and Engineering, PNL’s Laboratory Directed Research and Development program,. Sector 20 facilities at the Advanced Photon Source (APS), the DOE BES, the Canadian Light Source and its funding partners, the University of Washington, and the APS.   Electron microscopy was carried out in parts at the SuperSTEM Laboratory, the U.K. National Facility for Aberration-Corrected scanning transmission electron microscopy, which is supported by the Engineering and Physical Sciences Research Council (EPSRC). The research leading to these results has received funding from the European Union Seventh Framework Program.

The team’s paper, “Interface-Induced Polarization in SrTiO3-LaCrO3 Superlattices,” was authored by Ryan B. Comes1,*, Steven R. Spurgeon1,Steve M. Heald2, Despoina M. Kepaptsoglou3, Lewys Jones4, Phuong Vu Ong1, Mark E. Bowden5, Quentin M. Ramasse3, Peter V. Sushko1 and Scott A. Chambers, and published in  Advanced Materials Interfaces.

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We reported on the reputedly first 3D-printed airplane, a laser-sintered plastic craft with a structure we compared to that of the WWII Wellington bomber, almost five years ago.  Since then, the aircraft has been dubbed SULSA (Southampton University Laser Sintered Airplane) and taken its place with the Royal Navy.

Sun shines through geodesic structure of SULSA

Sun shines through geodesic structure of SULSA

Jim Scanlan, lead academic on the project and professor of design within engineering and the environment at the University, explains, “Not all of our aircraft are 3D printed and the biggest one is around 60 per cent 3D printed.  At the moment we make this lovely sophisticated lightweight structure and then spend a week making all the wiring and soldering. It’s labor-intensive and error prone. Our vision is that we print all the wiring into the structure at the same time and that will be a huge step forward.”

He credits the designer of the Wellington for inspiring the small craft’s internal geodesics.  “Barnes Wallis developed a very efficient geodesic structure in the Wellington bomber but it was difficult to manufacture.”  He credits 3D printing with the ability to produce an elliptical wing similar to that of another WWII workhorse, the Spitfire fighter.  “Both those old ideas had been parked but can now be reborn as 3D printing has removed a constraint.”

Test hopped from the HMS Mersey last July and landing on a Dorset beach, the airplane’s 500-meter (from shore) flight was a precursor to more adventurous assignments.  Assigned to the icebreaker Protector, it’s since made flights of up to 30 minutes, and every icy splashdown in Antarctic waters is followed by more flying, something a piloted aircraft (and pilot) would probably not be up for.

SULSA's meandering path above Dorset coatline last July

SULSA’s meandering path above Dorset coatline last July

Andrew Lock, from the University’s Computational Engineering and Design research group, oversees the frigid operations and ensures the video coverage of seas and icebergs ahead help keep the host ship safe on her passage.  The plane works with a small quadrotor to give full coverage of what’s ahead, helpful in situations where ice extends past a crow’s nest observer’s view of the horizon.  The quad flies short-range missions, while SULSA takes provides more far-seeing observations.

Royal Navy ships have been launching ScanEagle UAVs from frigates in the Persian Gulf for some time, but this marks the first time the service has flown UAVs in the Antarctic.  “The craft launched from Protector are smaller and less hi-tech, but still provided the icebreaker with real-time high-quality information courtesy of a detailed picture of the surrounding environment from a perspective that is only available from the air,” according to the University.

Printed from nylon in four major parts and assembled without the use of any tools – it is claimed by the University to be the world’s first ‘printed’ airplane.  Controlled from a laptop on the ship, it cruises at nearly 60 mph and is almost noiseless thanks to its tiny engine.  At a cost of £7,000 ($9,940), SULSA costs less than an hour’s flying time by a Fleet Air Arm helicopter.

Captain Rory Bryan, Protector’s Commanding Officer, observes that there may be a future for such budget-conscious operations.  “This trial of these low-cost but highly versatile aircraft has been an important first step in establishing the utility of unmanned aerial vehicles in this region.  It’s demonstrated to me that this is a capability that I can use to great effect.”

Andy Keane, Professor of Computational Engineering at the University of Southampton, said: “The series of flights conducted by Southampton staff in conjunction with the Royal Navy from HMS Protector has been a great success. These flights have shown just what can be achieved with smart design and low cost digital manufacture.”

Pictured: Personnel on HMS Protector's Fast Rescue Craft are seen here recovering the UAV after a successful flight. Unmanned Air Vehicle trials carried out onboard HMS Protector during her 2016 Antarctic Deployment. Andrew Lock, an Enterprise Fellow from Southampton University has been onboard HMS Protector carrying out UAV trials from the ship in order to research and gain an understanding in the use of UAVs onboard a ship. HMS Protector sailed from Plymouth in early October, travelling the long way East via the Suez Canal, Oman and Western Australia to Hobart so that she could conduct CCAMLR inspections in the Ross Sea. A recent visit to Christchurch, New Zealand, was very successful to develop liaison with the Antarctic community in the region. The majority of the Austral Summer period will be spent on the Australasia/Pacific Ocean side of Antarctica, before making her transit towards the Peninsula. HMS Protector conducts patrols on behalf of the Foreign and Commonwealth Office, surveys for the Hydrographic Office and provides logistic support to the British Antarctic Survey. The Ice Patrol Ship and her highly trained crew are well equipped to deploy personnel and equipment ashore in order to conduct operations.

HMS Protector’s launch personnel retrieve SULSA after icy splashdown

The Royal Navy and the University are both enthused by the outcomes of these early tests.  Commodore James Morley, the Navy’s Assistant Chief of Staff Maritime Capability, reports,

“Although this was a relatively short duration trial to measure the relative merits of fixed and rotary wing embarked systems, we are continuing to review our options for acquisition of maritime unmanned aerial vehicles in the future.”

The University of Southampton has pursued UAVs and advanced manufacturing for some time.  Their master’s degree program in unmanned aircraft systems is a potential trend setter.

The University gives a heads-up with their course overview.  “The future of exploration, transportation and conflict is in unmanned aircraft. Be the future and start a fascinating career on the precipice of national intelligence and technological advancements with a master’s in Unmanned Aircraft Systems Design. Sometimes referred to as drones, UAVs, UAS or RPAS, unmanned aircraft are revolutionizing our ability to monitor and understand our environment.

“This industry-led course focuses on the cutting-edge design of these sophisticated vehicles and is ideally suited to engineers looking to specialize or to enter into this fast-paced industry.”

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Dualing Ions in New Chinese Battery

Dual-ion intercalation alloying process probably won’t roll musically off the tongue, but the process has made a test cell that has greater specific density and energy density than the batteries in Teslas. Or the Chinese BYD electric sedan, according to its makers.

It’s “environmentally friendly” and low cost, to add to its sales appeal.

AGDIB in colorful schematic by Tang

AGDIB in colorful schematic by Yongbin Tang, leader of battery development team

Yongbin Tang and his colleagues at Shenzhen Institutes of Advanced Technology of the Chinese Academy of Sciences (CAS) have created an aluminum-graphite dual-ion battery (AGDIB) that, “Compared with conventional LIBs, …shows an advantage in production cost (~ 50% lower), specific density (~1.3-2.0 times), and energy density (~1.6-2.8 times).”

The team claims their battery can reach a volume energy density of the AGDIB ~560 Wh/L, “considerably higher” than Tesla’s Model S  Panasonic batteries (~350 Wh/L) or the BYD E6’s LiFePO4 lithium iron phosphate cells (~200 Wh/L).  The team further claims their battery outperforms electrochemical capacitors.

After 200 charge-discharge cycles, the battery has a reversible capacity of ~100 mAh g-1 and a capacity retention of 88 percent.  A” packaged” aluminum-graphite battery is estimated to deliver an energy density of ~150 Wh kg-1 at a power density of ~1200 W kg-1.  Depending on the meaning of the term “packaged,” which could include the normal accessories such as battery management systems that ensure even charging and discharging (perhaps not as crucial with this type of battery as with lithium-ion or –polymer batteries) and would account for lower performance numbers.

“Environmentally friendly” ingredients in AGDIB’s electrode materials consist of low cost aluminum and graphite only, while its electrolyte is composed of non-toxic, conventional lithium salt and carbonate solvent.  All materials are relatively easily recycled or repurposed.

“Dual Intercalation” means that there are two mechanisms at work to insert ions into the graphite cathode and the aluminum counter electrode.  During charging, anions in the electrolyte intercalate into the cathode with positively charged lithium ions in the electrolyte “deposit onto the aluminum counter electrode to form an aluminum-lithium alloy.  Discharging causes anions and Li+ ions to diffuse back into the electrolyte.

CAS explains one reason for the battery’s efficiency.  “Since the Al counter electrode in the AGDIB acts as the anode and the current collector at the same time, the dead load and dead volume of the AGDIB are significantly reduced, making a battery with both high specific energy density and high volume energy density.”

Unlike most batteries, the AGDIB contains no toxic metals – its electrode materials consist only of aluminum and graphite, while its electrolyte is composed of conventional lithium salt and carbonate solvent.

This AGDIB shows real potential for large-scale application in both electronic devices and electric vehicles. This technology may represent a revolutionary step for China’s energy industry. The successful commercialization of this new type battery has great potential to significantly enhance the performance of portable electronic devices, electric vehicles, and renewable energy systems.

This research was supported by the Guangdong Innovation Team and the National Natural Science Foundation of China.

A Novel Aluminum-Graphite Dual-Ion Battery,” published in the March 15 issue of Advanced Energy Materials, shows off the work of the team, including Xiaolong Zhang, Yongbing Tang, Fan Zhang, and Chun-Sing Lee.  ,

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Where Does Lilium Hide the Batteries?

Lilium is still in its incubator stage, but drawing a lot of interest for its radical two-seat, high-speed aerial vehicle.

EIT Climate-KIC, one of the funding organizations helping underwrite this startup, includes some startling claims in Lilium’s description.

“Lilium is designing the world’s fastest and highest-range electric aircraft that is commercially available.

“The two-seated light aircraft consumes half the energy of today’s most efficient electric cars and is so quiet that it can’t be heard flying in 1 km (@3,300 feet) altitude. It is propelled by electric impeller engines and features an extensive safety concept comprising a 3-fold redundant fly-by-wire control system, 12 redundant batteries and engines as well as a parachute rescue system for the whole aircraft.”

Possible early rendering of Lilium shows two canards with 12 ducted fans

Possible early rendering of Lilium shows two canards with 12 ducted fans

The ESA Business Incubation Center, another of Lilium’s backers, has more: “Lilium is developing, building, and selling a two-seated electric jet capable of vertical take-off and landing (VTOL). The company was founded in February 2015 by four engineers and Ph.D students from Technische Universität München. Lilium has developed an entirely new aircraft concept for vertical take-off (patent pending) that opens the door to a new class of simpler, safer, quieter, and more enduring VTOL aircraft. It has validated the concept with several scaled prototypes weighing 25 kg, and is now developing its first product: a two-seated ultralight VTOL jet. Lilium has a highly diversified team of experts in fields ranging from aerodynamics, flight control, and CFRP (carbon fiber reinforced plastic) structures to electric propulsion and product design. Together, its members are developing aircraft designed for use in everyday life.”

Promising to combine the weight of a European ultralight aircraft (472 kilograms, or 1,038.4 pounds all-up weight) with vertical takeoff and landing and 450 kilometers per hour (279 mph) top speed with an all-electric range of 500 kilometers (310 miles), Lilium would give Volocopter, Leaptech and Joby Aviation’s S2 runs for their money.

Another rendering shows one canard retracted with six ducted fans

Another rendering shows one canard (retracted) with six ducted fans

Theoretically, it would be safer than conventional airplanes or helicopters, using a triple-redundant control scheme and up to 42 ducted fans for vertical lift and forward thrust. Lilium states, “Its batteries, engines, and controllers are redundant, making the Lilium Jet a much safer concept than conventional helicopters.”

It would be a premium ride, with a side-by-side cockpit, touchscreen, joystick controls, wing doors, capacious luggage space, and automatically folding wings.  Last miles getting from the landing site to a final destination would involve folding the wings and driving Lilium as a very compact car.  Keeping a minimum of 36 motors, controllers and the necessary batteries within the confines of Lilium’s sleek pod, hauling a 180 kilogram (396 pound) payload and achieving the range target envisioned by Lilium would seem a challenge.

Lilium has more tricks than a Transformer® toy, with motors pivoting to provide vertical or horizontal thrust, and popping out on retractable canards as needed.

Lilium has highly aerodynamic shape, but raises question as to how everything fits inside compact pod

Lilium has highly aerodynamic shape, but raises question as to how everything fits inside compact pod

The aircraft’s projected 320 kilowatt (435 horsepower) output could be handled by even existing powerplants such as the Flytec HP-10, but its weight, for example, would make achieving payload goals difficult.  At 3.75 kilograms (8.25 pounds) per motor, even 36 would total 297 pounds – a substantial portion of the craft’s maximum all-up weight.   The video shows a different type of motor, which including fan and controller would have to be much lighter.  36 motors would have to put out 8.88 kilowatts each for the total, and 42 (shown in some concept renderings) would have to produce 7.6 kW each.

Batteries capable of lifting over 1,000 pounds and pushing the airplane at projected speeds, even for the 1.2 hours required to fly 300 miles at 250 mph would have to be superior to those available today.  Subtracting the payload from the all-up weight leaves only 642 pounds for aircraft structure, motors, batteries, and all the systems necessary for the transformations which Lilium undergoes on its journey.  Color this editor respectfully skeptical, but hopeful for advances in motors and energy storage.

We get basic details and illustrations on Ilium’s web site, and even more detail from Daniel Wiegand, Lilium’s CEO, in his presentation at London’s 2015 Eco Summit.

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e-volo’s Volocopter VC200 made its first “manned” flight on March 30, 2016, with managing director Alexander Zosel maintaining control for a few minutes, and then letting the 18-rotor vehicle find its own way.  He held both hands out the side door for several seconds to show the Volocopter was flying itself – and quite stably in hover at that.  He repeated the hands-off approach later in the flight.

Zosel lightly held the single control stick in the machine, controlling vertical motion through thumb movement on the video-game-type controller, lateral motion by twisting the control stick, and banking by tilting the control stick.  It all seems intuitive and well harmonized.  The videos show the flight and its happy aftermath.

Unlike conventional helicopters that require both hands and both feet on the controls, usually in subtle motions that resemble Ringo Starr or Buddy Rich at their best, the single control stick in the VC200 is, according to all concerned, pretty intuitive.

How long will it be before an “Intel Inside” decal appears on the Volocopter’s flanks?  German drone maker Ascending Technologies developed “technology assistance” for the multicopter.  Intel Corporation recently acquired Ascending Technologies, which makes Intel Capital a direct shareholder in e-volo through that shareholding position.

Josh Walden, senior vice president and general manager of Intel’s New Technology Group, sees a future in this arrangement. “Intel congratulates e-volo on this accomplishment.  Technology developed by Ascending Technologies assists in the flight controls, motor electronics and key elements that extend multi-rotor UAV technology to this new type of aircraft. We look forward to aiding the development of more manned and unmanned vehicles in the future.”

The next two years should be exciting for e-volo, with a push to obtain type certification and produce the Volocopter in large quantities.  The company hopes to enter “the well-established air sports market,” and then establish air taxi services, initially flying predetermined routes as airport shuttles, or picking up passengers at “sensible traffic nodes.”  e-volo sees future public and individual transport in their little machine, perhaps an Uber of the skies.

NASA invited Florian Reuter, the team’s Managing Director of Strategy & Finance to present at a recent “On-Demand Mobility” workshop in Washington, D. C.  This, coupled with a discussion of how to develop a legal framework that would allow individual flights in urban areas for everyone, complemented a NASA study which highlights the “positive contribution such a system would have on the alleviation of the daily traffic congestion in the Silicon Valley region in California.”

We’ll check back as flight tests continue on this promising design.  e-volo has accomplished a great deal since the first landing on a Pilates ball four years ago.  The next four years should be very exciting.

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