California Institute of Technology (CalTech) floats this imaginary trial balloon to elicit interest in a new material developed by materials scientist Julia Greer and her colleagues.  “Imagine a balloon that could float without using any lighter-than-air gas. Instead, it could simply have all of its air sucked out while maintaining its filled shape. Such a vacuum balloon, which could help ease the world’s current shortage of helium, can only be made if a new material existed that was strong enough to sustain the pressure generated by forcing out all that air while still being lightweight and flexible.”

Not only are the scientists achieving the strong, lightweight part of the equation, they are “on the path” to making their new material “non-breakable” and able to return to its original size and shape when squished.

As described in her talk shown above, she and her group turned to architectural solutions, only making their bridge-like trusses at the nano scale – where things work very differently.  It’s a bit like the material side of quantum mechanics.  In this case, ceramics, normally extremely strong but exceedingly brittle, become flexible like NERF (Non-Expanding Recreational Foam for those who wondered what the name meant) – not a typical ceramic reaction to compression.

A Greer Lab nanolattice compressed

A Greer Lab nanolattice compressed.  Notice the scale of these cubes

Greer’s ceramic contains about 99.9 percent air and is deposited on a sub-microscopic scaffold that gives the material its structural shape.   She performed earlier magic working with researchers at HRL Laboratories making a microlattice of hollow metal tubes.  The blog reported on that in 2011.

Turning this same type of structural concept to ceramics presented challenges, though.  Greer says,“Ceramics have always been thought to be heavy and brittle. We’re showing that in fact, they don’t have to be either. This very clearly demonstrates that if you use the concept of the nanoscale to create structures and then use those nanostructures like LEGO® to construct larger materials, you can obtain nearly any set of properties you want. You can create materials by design.”

Schematic showing the fabrication process for hollow ceramic nanolattices. The nanolattices are first written out of a photopolymer using two-photon lithography direct laser writing. The polymer scaffolds are coated using atomic layer deposition (ALD) and the underlying polymer is exposed to air using focused ion beam milling. The polymer is then removed using O2 plasma etching, leaving behind a hollow ceramic nanolattice. Credit: Lucas Meza; Caltech

Schematic showing the fabrication process for hollow ceramic nanolattices. The nanolattices are first written out of a photopolymer using two-photon lithography direct laser writing. The polymer scaffolds are coated using atomic layer deposition (ALD) and the underlying polymer is exposed to air using focused ion beam milling. The polymer is then removed using O2 plasma etching, leaving behind a hollow ceramic nanolattice. Credit: Lucas Meza; Caltech

Greer’s team made the ceramic nano-trusses by 3-D “printing” with polymers using something called two-photon interference lithography.  They then coated the lattice with a ceramic such as alumina.  After that, the team etched out the polymer with an oxygen plasma, ending up with a lattice of hollow ceramic tubes.

Different tube wall thicknesses can control how the material fails.  Thick walls cause the ceramic to shatter under pressure, much like a tea cup when dropped.  Thinner walls, around 10 nanometers thick, buckle under compression but recover their shape when the pressure is removed.  Some structures could be compressed by as much as 85 percent and still recover.

Greer’s lab showed that by changing the thickness of the tube walls, it’s possible to control how the material fails. When the walls are thick, the ceramic shatters under pressure as expected. But trusses with thinner walls, just 10 nanometers thick, buckle when compressed and then recover their shape.  The team produced hollow-tube alumina structures with walls ranging in thickness from 5 to 60 nanometers and tubes from 450 to 1,380 nanometers in diameter.

Surprisingly, the density of the ceramics used can be compared to balsa wood, although the ceramics in their nanolattice structures would have better strength- and stiffness-to-weight ratios than the wood.

Greer thinks the applications for this technique are practically limitless, including the making of artificial bones that might have better characteristics than the real thing.  The scaffold alone could allow a patient’s own cells to coat the lattice.  Because coatings could include conductive materials, Greer is working with Bosch in Germany to find possible applications for this nano-technology in batteries.  The ultra-porous nature of the lattices would certainly seem to allow extremes of lithium intercalation.

The Greer lab is also investigating ways to produce these structures at mass scales, with processes like roll printing as one possibility.

Lucas R. Meza is lead author on their paper, “Strong, Lightweight and Recoverable Three-Dimensional Ceramic Nanolattices,” Others include co-author Satyajit Das.

Imagine a future, as Greer says, in which a giant cargo airplane would weigh no more than the scale model of that craft.  This is not idle speculation, because Dennis Bushnell, Chief Scientist at NASA’s Langley Research Center has posited the identical possibility.  This type of thinking will change the way in which we think of structures, propulsion, and a host of other elements.  This could get interesting.

One more thing, unrelated to the topic of structures and nanomaterials: Julia Greer is also an accomplished pianist, According to her CalTech biography.  “Julia has also been pursuing her ‘secondary career’ as a concert pianist – having studied at the Moscow’s Gnessin School of Music, the Eastman School of Music, the San Francisco Conservatory of Music, and at Stanford. She has performed numerous solo recitals (most recently at Caltech’s ‘Off the Clock’ event in 2011), chamber music concerts (most recently in Lagerstrom Series at Caltech with violinist C. Kovalchik), as well as a soloist with an orchestra (most recent performance of Brahms’ Piano Concerto No. 2 with the Redwood Symphony).”

She appeared as a guest on a Discovery Channel show in the spring of 2012, hosted by Adam Savage and Jamie Hyneman from Mythbusters!

 

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For the last 60 years, your editor remembers the oft-repeated advice from garage mechanics and now lithium-ion advocates that slow charging is the way to make your batteries last for many cycles.  Where does this put Tesla, for instance, with its 20-minute Superchargers?  Are you damaging your expensive cells by being in a hurry?

Batteries under test at SLAC with different voltages and currents flowing through them

Batteries under test at SLAC with different voltages and currents flowing through them

In yet another example of counter-intuitive thinking at work, researchers at SLAC, the National Accelerator Laboratory at located on the Stanford University campus have challenged several tenets of conventional battery wisdom.  According to PC World, their work, “published on Sunday in the Journal, Nature Materials, challenges the commonly held notion that slowly charging a battery helps prolong its life and that it’s damaging to a battery if a large amount of energy is withdrawn in a short time.”

William Chueh, a senior author of the paper and researcher at the Stanford Institute for Materials and Energy Sciences (SIMES), told the magazine, “’We’ve always thought of a battery as a [single] device, but inside an iPhone battery there are a few trillion particles.’”  He pointed out that usually scientists look at how the entire battery behaves instead of looking at the individual particles within the battery.

In a Stanford press release, Chueh added, “The fine detail of what happens in an electrode during charging and discharging is just one of many factors that determine battery life, but it’s one that, until this study, was not adequately understood. We have found a new way to think about battery degradation.”

This may inform scientists working on commercial development of lithium-ion batteries, showing possible new ways to design electrodes and promote more uniform charging and discharging that will extend battery life, according to Stanford.

X-ray microscope snapshot of nanoparticles in a battery midway through charging. Particles range from fully charged (green) to intermediate charge (orange/yellow) to drained of charge (red). The scalebar equals 500 nm. (SLAC National Accelerator Laboratory)

X-ray microscope snapshot of nanoparticles in a battery midway through charging. Particles range from fully charged (green) to intermediate charge (orange/yellow) to drained of charge (red). The scalebar equals 500 nm. (SLAC National Accelerator Laboratory)

Using the particle accelerator at the Department of Energy’s SLAC facility in Menlo Park, California, the team was able to see individual nanoparticles in the slices of the batteries under test, much like an MRI on a human.  As the batteries were charged and discharged, the team got a first-time look at the internal processes of the test cells.

Unlike the animations we often see of neatly marching electrons filing through the battery, individual particles get charged for brief periods, after which the current passes to the next particle.  These quick particle-by-particle actions were a surprise, “because rapid charging was also thought to be damaging to batteries.”

Slow charging is usually a relatively low-temperature process, so the battery is protected from thermal damage, but researchers found “The uniformity of each particle’s charge seems to be more important than the speed of the charge.”

Researchers think they can add life to batteries by charging them differently; making lithium-ion batteries that now manage a few years last up to 10 years.  The uniform charging causes less localized heating in the cell and slows degradation, even at high charging rates.

Another aspect of battery design, anodes and cathodes, swell and shrink during charging and discharging, absorbing and releasing electrolyte.  If battery makers can spread the work around to more of the billions of nanoparticles of lithium iron phosphate that make up these electrodes, they have another way to make the battery last longer.  When only a few of the particles carry the charge/discharge load, they tend to crack and break down quickly.  Uniform loading across the entire electrode will lessen stresses and prolong the system’s life.  Researchers found that real-life observations matched data from a model developed at MIT.

The team thinks their research will benefit both stationary and mobile battery applications, with improved batteries better able to handle power surges on the grid or sudden demands by a driver (or pilot).  Before such applications become commonplace, the team must run more tests, trying their modified electrodes through thousands of cycles to simulate hoped-for endurance and performance.  Not content to rest on their academic laurels, the team is talking with companies in the consumer electronics and automotive industries, presumable about commercialization of their final products.

The team included members from the Massachusetts Institute of Technology, Sandia National Laboratories, Samsung Advanced Institute of Technology America and Lawrence Berkeley National Laboratory.

Their paper, “Current-induced transition from particle-by-particle to concurrent intercalation in phase-separating battery electrodes,” can be found here.

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Aside from Lucas di Grassi  and Audi  Sport ABT winning the first Formula E race in Beijing, China over the weekend, it would have been almost unremarkable except for the last-lap, last corner collision between Nicolas Prost and Nick Heidfeld.  The spectacular crash was TV news worthy, and despite the initial friction during and after the crash, Prost and Heidfeld both sent mea culpa apologies to each other via social media.  Formula e races, so far, seem fairly civilized affairs.

35 of the other 40 starters, all essentially alike aside from their team paint jobs, crossed the finish line unscathed and having burned nothing but rubber during their 45 minutes around the 3.44 kilometer (2.13 miles) track.  Even the charger used to “fuel up” the racers burns pollution-free glycerin provided by Aquafuel, a British-based specialist in renewable fuels, according to Formula E Holdings.

Aquafuel explains that, “Glycerin is a by-product of biodiesel production.  For every 9 gallons of biodiesel, 1 gallon of crude glycerin is produced.  Glycerin’s density and high oxygen content offer the potential of exceptionally clean combustion, with much lower emissions than burning diesel fuel.  Aquafuel’s technology has turned that potential into practical reality.”  Glycerin can also be derived from animal fat in a rendering plant, rendering the plant into an essentially self-fueling enterprise.  Its promoters claim the fuel can be made from algae grown in salt or brackish water, and requires no otherwise potable water or necessary agricultural land – a huge benefit in the fight to feed everyone while still powering the world.

A single generator charges all 40 cars “from flat to full in 50 minutes and with automated precise power controls, can be relied upon to ensure no car is given additional power.”  This macro-battery management system ensures that all cars are indeed equal off the line.  Competitors need to manage their energy use, though.  One finisher lost out on a higher standing because of using two percent more energy than allowed for the full circuit.

The cars are serious competition vehicles, able to accelerate from 0 to 100 kilometers per hour (62 mph) in just three seconds.  Because batteries run down quickly under the extremes imposed by racing, each team’s two drivers also have two cars, and switch from the depleted vehicle of the first half of their run into a freshly-charged duplicate for the second half of the race.  This mid-race car swap is one of the quirkier elements of this new style of racing, but was chosen over swapping batteries – considered the riskier option by rule makers.

Because Williams joined the competition only 15 months before the series scheduled opening (the original supplier backed out), their 300 kilogram (660 pound) battery pack was a rush order.  It’s roughly the same weight and holds approximately the same energy as a Leaf battery pack at 28 kilowatt hours vs. the Leaf’s 24 kWh.  Since the Leaf pack can be replaced for $5,500, the Williams Formula E cells might be a little pricier.

The FIA (Fédération Internationale de l’Automobile) Formula E  web site lists maximum power as 200 kilowatts, equivalent to 270 brake horsepower, which in power saving race mode is limited to 150 kW, or 202.5 bhp.  In another quirky feature of Formula E, fans can vote for their favorite car or driver and allow boosts in power to 180 kW for five seconds.  The additional 30 kW (40.5 bhp) should be about like a kinetic energy recovery system in a “conventional” Formula 1 car.  Having its activation be spectator based will add an element of possible fickleness in relative performance between cars.

Renault Formula E chassis, two per team - in this case the Andretti Autosport group

Renault Formula E chassis, two per team – in this case the Andretti Autosport group

All the cars racing this season are the same Renault chassis vehicles with the same battery and motor limitations.  Season two will allow other builders to participate, and with modified rules, we might see a truly new racing technology.  Experience gained here will surely translate into lighter, more powerful batteries and motors that may find their way into future aircraft, with Williams already working with a British air-racing team.

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Cheap Hydrogen, Anyone?

Researchers in Glasgow and at Stanford University have devised ways to decouple oxygen and hydrogen from water without resort to expensive extraction or storage techniques.  Both breakthroughs involve low-cost materials, low-energy requirements, and the production of clean hydrogen through what should be renewable energy resources.

The latter overcomes one major objection to hydrogen production.  As Professor Lee Cronin of the University of Glasgow’s School of Chemistry explains, “Around 95% of the world’s hydrogen supply is currently obtained from fossil fuels, a finite resource which we know harms the environment and speeds climate change. Some of this hydrogen is used to make ammonia fertilizer and as such, fossil hydrogen helps feed more than half of the world’s population.

Professor Lee Cronin in his Glasgow laboratory

Professor Lee Cronin in his Glasgow laboratory

“The potential for reliable hydrogen production from renewable sources is huge. The sun, for example, provides more energy in a single hour of sunlight than the entire world’s population uses in a year. If we can tap and store even a fraction of that in the coming years and decrease our reliance on fossil fuels it will be a tremendously important step to slowing climate change.”

Their new method, according to Professor Cronin and his team, produces hydrogen 30 times faster than current state-of-the-art methods which involve electrolysis, and often rely on fossil fuels to power the operation.  Current approaches often use proton exchange membrane electrolyzers (PEMEs) with precious metal catalysts to generate the hydrogen.  These catalysts are held in high-pressure containers and the process requires large electric currents – something not always available from renewable sources.

The Glasgow method works at atmospheric pressures and low voltages, solving problems normally found “with generating electricity from renewable sources such as solar, wind or wave energy.”

It overcomes the issue of needing to immediately use the hydrogen or store it, usually an involved process.  Professor Cronin explained the method and the advantages of the new approach. “The process uses a liquid that allows the hydrogen to be locked up in a liquid-based inorganic fuel. By using a liquid sponge known as a redox mediator that can soak up electrons and acid we’ve been able to create a system where hydrogen can be produced in a separate chamber without any additional energy input after the electrolysis of water takes place.

“The link between the rate of water oxidation and hydrogen production has been overcome, allowing hydrogen to be released from the water 30 times faster than the leading PEME process on a per-milligram-of-catalyst basis.”

The research was produced as part of the University of Glasgow Solar Fuels Group, which is working to create artificial photosynthetic systems which produce significant amounts of fuel from solar power.  This effort is similar to work done by Dr. Daniel Nocera at MIT and Harvard in the United State.

Professor Cronin along with Dr. Greig Chisholm, Dr. Mark Symes and Benjamin Rausch contributed to the paper, “Decoupled catalytic hydrogen evolution from a molecular metal oxide redox mediator in water splitting,” published in Science

Stanford University researchers, headed by Hongjie Dai, obviously looking for similar low-voltage results, have crafted a water splitter that runs on an ordinary AAA battery hooked up to low-cost nickel and iron electrodes used to bubble oxygen and hydrogen from the water at room temperature.

Dai explained, “It’s been a constant pursuit for decades to make low-cost electrocatalysts with high activity and long durability.  When we found out that a nickel-based catalyst is as effective as platinum, it came as a complete surprise.”

Stanford's triple-A battery-powered water splitter

Stanford’s triple-A battery-powered water splitter

Stanford graduate student Ming Gong, co-lead author of the study, found the nickel equivalency to platinum – at least as far as water splitting goes. Stanford reports, “Ming discovered a nickel-metal/nickel-oxide structure that turns out to be more active than pure nickel metal or pure nickel oxide alone,” Dai said. “This novel structure favors hydrogen electrocatalysis, but we still don’t fully understand the science behind it.”

Not only is the nickel/nickel-oxide catalyst significantly lower in cost, it “significantly lowers the voltage required to split water, which could eventually save hydrogen producers billions of dollars in electricity costs.”  Gong’s next goal is to improve the durability of the device to prevent regular swapping out of defunct electrodes.  Researchers also plan on developing a solar powered system, to do away with constantly having to replace those little batteries.

Not content with just providing hydrogen for California’s planned fleet of fuel-cell cars, the team notes that the same device can produce chlorine gas and sodium hydroxide, an important industrial chemical.  Their device and its operation are described in their paper in the August 22 issue of the journal Nature Communications.

“Hydrogen is an ideal fuel for powering vehicles, buildings and storing renewable energy on the grid,” said Dai. “We’re very glad that we were able to make a catalyst that’s very active and low cost. This shows that through nanoscale engineering of materials we can really make a difference in how we make fuels and consume energy.”  The team, unlike that in Glasgow, fails to mention how the hydrogen produced will be stored, at least in their paper’s abstract.

Dai and Gong worked with Wu Zhou, Oak Ridge National Laboratory (co-lead author); Mingyun Guan, Meng-Chang Lin, Bo Zhang, Di-Yan Wang and Jiang Yang, Stanford; Mon-Che Tsai and Bing-Joe Wang, National Taiwan University of Science and Technology; Jiang Zhou and Yongfeng Hu, Canadian Light Source Inc.; and Stephen J. Pennycook, University of Tennessee.

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Where Are They Now? The Electric Phoenix

MGM COMPRO, a Czechoslovakian motor and electronics supplier, announced that they had participated in finally making the Phoenix motorglider an electric machine.  Jim Lee and co-pilot Jeff Shingleton had originally intended to fly the airplane at the Green Flight Challenge three years ago, but contented themselves with competing in the Rotax-powered machine and “only” winning third place in the event.  Their competing did elicit a great deal of interest in the machine, though.

MGM says, “We are very glad that we can present you a very successful project, [the] U-15 Phoenix of the Czech entrepreneur Martin Stepanek.  MGM COMPRO plays a decisive role in a development of industrial controllers for this fully electric aircraft.

Phoenixes Rotax and electrically powered show earlier low-wing configuration for electric version

Phoenixes Rotax and electrically powered show earlier low-wing configuration for electric version

As described in the blog three years ago, the electric PhoEnix is a “nice airplane,” and one that would take many willing pilots on many cross-country jaunts.  Martin originally planned to use a Czech industrial motor for power, but ended up developing his own powerplant that would allow use of a controllable-pitch and feathering propeller.  He turned to MGM COMPRO for the motor controller, an industrial model HBC 280120, and uses two lithium-ion battery packs to give an hour’s endurance.

Martin and his team have planned a 6-day flight around the Czech Republic, cruising at about 120 kilometers per hour (74.4 mph) for an hour at a time.  Depending on reports, recharging can take one to 2.4 hours, so several hops could be accomplished in a day.

Three-view shows mid-wing configuration of electric Phoenix

Three-view shows mid-wing configuration of electric Phoenix

The two-seat motorglider has a wingspan of 14.5 meters (47.56 feet) and a length of 6.5 meters (21.32 feet).  Its empty weight of 300 kilograms (660 pounds) includes 34 kilograms (74.8 pounds) of batteries, not the 110 pounds reported for the round-Czechoslovakia trip.  Differing from the Rotax-powered version in having mid-fuselage-mounted wings rather than low wings and in seeming to have the retractable gear earlier planned, the sharp-nose vehicle shows several aerodynamic improvements that would allow it to take full advantage of its electric power.

Martin Stepanek is not new to all this, having worked on sailplanes during his mandatory army service in 1998 and 1999, and studying at the Aeronautical University in Brno (1993-1998). From 1999 to 2007 he worked at Urban Air on the Samba and Lambada ultralight motorgliders.   In 2008 he stared development of the Light Sport Aircraft, motorglider Phoenix and by 2009 was test flying  the machine.  By 2011, he was doing initial test flights of the electric version.

He showed the airplane at this year’s Aero Expo at Friedrichshafen and told reporters he was studying allowing the propeller to windmill in thermals to regenerate power for the batteries.  This should expand the range and endurance well beyond one hour, since Jim Lee has one video showing him flying 127 miles in the later afternoon without power in his demonstrator.

These types of aircraft are enormously adaptable, and with soaring capabilities can expand a pilot’s repertoire and skills.  It’s great to see this “new” airplane three years later.

NOTE: Please check out the comment from the airplane’s designer below for current information on the power system.

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Recycling Tires for Battery Anodes

Old tires are hard to get rid of, and left in small mountains in salvage yards, can self-incinerate, causing massive clouds of dangerous smoke and lakes of toxic goo. Fires can last for months, virtually unassailable by fire fighters. Some still structurally sound tires can be re-treaded and gain a new life on the road.  Others, well past their usable life, are shredded and added to an asphalt mix to have a new life as the road.

Not so funny in real life, the Springfield tire fire has been burning since 1989 on the TV program, The Simpsons

Not so funny in real life, the Springfield tire fire has been burning since 1989 on the TV program, The Simpsons

They might also end up lithium-ion batteries.  According to Oak Ridge National Laboratory, “Recycled tires could see new life in lithium-ion batteries that provide power to plug-in electric vehicles and store energy produced by wind and solar, say researchers. By modifying the microstructural characteristics of carbon black, a substance recovered from discarded tires, a team is developing a better anode for lithium-ion batteries.”

A team led by Parans Paranthaman and Amit Naskar is developing a better anode, the negatively-charged electrode, for lithium-ion batteries.   They have created carbon black from waste tires in a “small, laboratory-scale battery” that gives a reversible capacity higher than that from commercial graphite materials – the anode contributing about 390 milliamp hours per gram after 100 cycles.   Researchers think this is attributable to the “unique” microstructure of the carbon black produced from the waste tires.

Process uses an airless fire to create unique  carbon black for battery anodes

ORNL process uses an airless fire to create unique carbon black for battery anodes

ORNL reports, “’This kind of performance is highly encouraging, especially in light of the fact that the global battery market for vehicles and military applications is approaching $78 billion and the materials market is expected to hit $11 billion in 2018,’ Paranthaman said.”

Naskar added that with anodes accounting for 11 to 15 percent of the battery materials,   “This technology addresses the need to develop an inexpensive, environmentally benign carbon composite anode material with high-surface area, higher-rate capability and long-term stability.”

Paranthaman, Naskar and co-authors Zhonghe Bi, Yunchao Li, Sam Akato, Dipendu Saha, Miaofang Chi and Craig Bridges published their paper titled “Tailored Recovery of Carbons from Waste Tires for Enhanced Performance as Anodes in Lithium-Ion Batteries,”  in the journal, RSC Advances.  The team, “envision[s] batteries featuring this technology being highly marketable.” 

ORNL reports the team is “working with David Wood and Jianlin Li on a pilot manufacturing process to scale up the recovery of material and demonstrate applications as anodes for lithium-ion batteries in large-format pouch cells. Researchers expect these batteries to be less expensive than those manufactured with commercial carbon powders.”

Although the batteries will probably not be as powerful as those with silicon-based electrodes, they will provide an inexpensive route to EV adoption with performance that may be usable even in aircraft.

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What Did You Do Over the Labor Day Weekend?

KillaJoule is the world’s fastest electric motorcycle with a top speed of 241 mph (388 km/h) so far.  About 80 percent of this sleek bullet is the design and work product of co-owner and driver Eva Håkansson, who has graced the stage at two Electric Aircraft Symposiums, the last appearance with her husband and crew chief, Bill Dube’. 

Their web site explains, “KillaJoule is really eco-activism in disguise. The only purpose of this 19 foot, 400 horsepower, sleek, sexy motorcycle is to show that eco-friendly doesn’t mean slow and boring.”

Eva and KillaJoule in matching red outfits.  Photo: BonnevilleStories.com

Eva and KillaJoule in matching red outfits. Photo: BonnevilleStories.com

Over the Labor Day weekend, Eva lowered her petite frame (she’s about five feet tall) into the cockpit of her speedy sidecar to break her old world record and set a new mark 25 miles per hour faster than anyone else has gone before in or on a motorcycle.  The sidecar definition comes from the outrigger wheel and platform that thankfully, doesn’t require a rider for these speed attempts.

The bike (trike?) weighs a mere 1,540 pounds with Eva on board, giving a weight to power ratio of 3.85 pounds per horsepower at the 400-hp rating, or only 3.08 pounds per horsepower if Eva opened the throttle all the way (probably good only for very short bursts of power).  Compare that to an Indianapolis race car, which weighs between 1,545 and 1,575 pounds depending on tires and has an internal-combustion engine producing an “estimated 550-700 horsepower depending on variable turbo boost used at [the] track.”  Both are positively svelte compared to a Lamborghini Aventador with a dry weight of 3,472 pounds and power output of 700 horsepower (4.96 pounds per horsepower).

It's obvious that the car was literally designed around Eva

It’s obvious that the bike was literally designed around Eva.  Photo: Phil Hawkins

Eva wires her own battery packs, a meticulous and somewhat anxiety-provoking thing to watch, and has crafted a 400 Volt, 10 kilowatt-hour, 500 horsepower package for KillaJoule.  The A123 Systems lithium nano-phosphate cells power an EVO Electric AFM-240 motor that is capable of 500 horsepower at full tilt. Two Rinehart Motion Systems PM100 controllers that can manage 400 horsepower between them keep it all working in harmony.

The vehicle is only 21 inches wide and about 38 inches high.  The video, because of the wide angle lens used, fails to allow full comprehension of the claustrophobic of the driving position.  The sidecar gives a track width of 45 inches, not enough to claim wide track status.  Nevertheless, Eva manages with notable finesse, keeping the red machine threading the needle between marker poles with precision.

Sven Håkansson, her father and senior adviser to the team, designed the “Springer ”style front suspension and “classic stereo” rear suspension.  It seems to give a smooth ride, even when the fore and aft disk brakes and twin Kevlar ribbon braking parachutes bring things to a quickly decelerated halt.

The winning ticket at Bonneville Salt Flats

The winning ticket at Bonneville Salt Flats

The team claims KillaJoule is theWorld’s fastest electric motorcycle and the world’s fastest sidecar motorcycle @ 240.726 mph (387 km/h) (AMA Record, pending ratification, set in August 2014). Complete list of records here.  It is also the world’s 4th fastest battery-powered vehicle (higher records were set by the cars White Lightning and Buckeye Bullet 1 and 2.5).”

KillaJoule’s registered top speed is “currently 241.901 mph (as of August 2014).”  Congratulations to Eva, Bill and the entire racing team, including Mike Stockert, Alicia Kelly and Kent Singleton.  Eva Håkansson will be more inspiring than ever to the classrooms of young girls she encourages to enter Science, Technology, Engineering and Math (STEM) fields of study.  Nobody nods off during her sessions.

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Although “large nanostructures” may sound like the same kind of oxymoron as “jumbo shrimp,” such things are relative even at the smallest of scales. 

Dr. Avetik Haryutunyan, Chief Scientist in the Materials Science Division of Honda Motors in Columbus, Ohio, shared a small part of the knowledge contained in his numerous publications and patents with the audience at the eighth annual Electric Aircraft Symposium last April.  He reviewed experimental approaches to creating high lithium storage in carbon nanostructures, with the ideal of providing scientists and commercial developers usable materials and products.

Rice University and the Honda Research Institute use single-layer graphene to grow forests of nanotubes on virtually anything. The image shows freestanding carbon nanotubes on graphene that has been lifted off of a quartz substrate. One hybrid material created by the labs combines three allotropes of carbon – graphene, nanotubes and diamond – into a superior material for thermal management - one of many research avenues followed by Dr.

Rice University and the Honda Research Institute use single-layer graphene to grow forests of nanotubes on virtually anything. The image shows freestanding carbon nanotubes on graphene that has been lifted off of a quartz substrate. One hybrid material created by the labs combines three allotropes of carbon – graphene, nanotubes and diamond – into a superior material for thermal management – one of many research avenues followed by Dr. Haryunyan: Photo from Science Daily

He reviewed the many experimental approaches to enhancing energy storage with lithium, attempting to achieve reproducibility and irreversibility, two touchstones of scientific validation.

Dr. Haryutunyan explained that with 14 Terawatts of energy consumption in the United States today and an anticipated requirement for 30 to 60 terawatts by 2050, we would have to build one or two nuclear plants every day for the next several decades to meet the need.   Whether we get energy from nuclear, wind or solar, we’ll still need to store that energy for portable devices and electric vehicles.  This will require light, multifunctional materials to reduce the weight and improve the efficiency of future batteries.

He discussed the long history of energy storage, including the controversial and possibly mistakenly named” Baghdad battery,” which may never have stored a single electron, but which could remotely have been used as a battery.  An iron rod in a copper sheet, immersed in an acidic solution such as vinegar of lemon juice, will generate a current flow, but whether people in what is now Iraq knew that 2,000 years before the common era is open to speculation.

Graphite has long been a common material for batteries, with its theoretical maximum energy density of 880 Watt hours per kilogram, although that is actually lower in practice.  It allows storage of only one lithium atom for every six carbon atoms, limiting a battery configured this way to a capacity of only 372 Amp-hours per kilogram, certainly nothing to get excited about.

Nantechnology has allowed researchers to tune material to get something new.  Professor Richard Smalley pioneered research at the nanoscaale, and following his death, left the Smalley Institute at Rice University, focused on 5 Grand Challenges: energy, water, environment, disease, and education. Dr. Haryutunyan focuses, of course, on energy, although many of his researches impinge on medical areas, with materials he helps develop having diagnostic and healing potential.

Carbon nanotubes (CNTs) have much higher energy storage capabilities than ordinary carbon – up to 1,116 mA/g with randomly disordered material.  These tubes, essentially rolled-up graphene sheets, have more space to absorb lithium.  But the binding of lithium sometimes forms clusters which mitigate against high energy storage.  This has led to forming graphene not only into nanotubes, but nanotube yarns and cables, looking like spaghetti or forests made of these tubes.

All these are attempts to provide more space to absorb more lithium and gain more storage capacity.  A variety of approaches have been tried, including single and multi-wall nanotubes, graphene flakes and graphene networks grown on nickel foam.  These sometimes lead to problems with retaining the capacity of the material, with rapid losses after the first and second full charge/discharge cycle.

As shown with Raman spectroscopy, energy peaks don’t recover, and irreversible effects follow.

To gather and gain useful “work” from a significant number of lithium ions, nanoscale materials can use a variety of specific defects to increase energy and prevent lithium clusters.  These specific defects are hard to reproduce, and a great deal of research is necessary, apparently, to make the sometimes excellent results Dr. Haryutunyan and his teams achieve into a normal outcome for everyone who wants similar products.

The teams are attempting to use boron in place of carbon, and realizing that silicon can absorb more lithium ions than graphite, are looking toward that material for further gains.  Science at this specific and focused a  level does not readily lend itself to front page news stories, but is essential to making the scientific and commercial breakthroughs that we see in the popular press a reality.

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Dr. Ann Marie Sastry, CEO of Sakti3, Inc. of Ann Arbor, Michigan, has been quietly working on a high-energy-density battery that would use mass production platforms with “fully scalable equipment” that would take us to the next level of development.

Dr. Ann Marie Sakti with pilot-scale manufacturing equipment

Dr. Ann Marie Sastry with laboratory-scale equipment

Sakti announced this week that its new battery can store over 1,100 Watt hours per liter (Wh/l) in volumetric energy density, about two to four times that for conventional cells.  Scientific American reports 1,143 Wh/l.  According to Sakti’s release, “This translates to more than double the usage time in a wearable device like a smartwatch, from 3.5 hours to more than 9 hours. It also translates to almost double the range in an EV like the Tesla Model S, from 265 miles to 480 miles.”

Besides the performance improvement, Sakti claims to be able to produce the new, solid-state battery that would rely on a “full scale plant layout to avoid any high cost materials, equipment or processes.”  Professor Wei Lu from the University of Michigan is a battery expert knowledgeable about the process – and also having no financial or other interest in Sakti3. “It’s not either/or in cost and performance in batteries anymore – Sakti3 has both. They built a really high performance device on a really low cost platform – like building millions of high end processors in a factory that produces ordinary plastic wrap. It was quite a scientific feat.”

He vouches for the accuracy of the Sakti numbers.  “They have a very rigorous testing facility.  Their results are highly impressive and very accurate.”

Sakti 3 battery has solid electrolyte, can be manufactured on thin-film deposition equipment

Sakti 3 battery has solid electrolyte, can be manufactured on thin-film deposition equipment

Sakti3’s solid-state battery is produced with the same thin-film deposition process used to make flat panel displays and photovoltaic solar cells.  As noted in the blog last week, Applied Materials has been supplying that type of “large area” manufacturing equipment to an un-named enterprise for production of batteries that would fit that process.

Scientific American explains the process and construction of the cells: “Sakti3’s technology is solid-state battery produced with the same thin-film deposition process used to make flat panel displays and photovoltaic solar cells. The cell contains no liquid electrolyte; an “interlayer” acts as both the separator, which keeps the positive and negative electrodes from coming into contact, and the electrolyte, allowing desirable ion transfers to take place.”

Sakti 3 claims to have the safest cells ever demonstrated because of their all solid-state construction and cell materials.  Their video of a technician dropping hot solder onto an operating cell, with only moderate spikes when the molten metal hits the battery, is a large contrast to the fiery deconstruction of other cells.  The battery continues to discharge without drama.

The company concludes it announcement:”’Our target is to achieve mass production of cells at ~$100/kWh,’ said Dr. Ann Marie Sastry, CEO of Sakti3. ‘Our key patents on the technology have been issued, we are up and running on larger tooling, and can now speed up processing. Our first market will be consumer electronics, and after that, we’ll move to other sectors.’”  Compared to the $238/kWh of a Tesla battery, $100 would make less expensive EVs a real possibility.  The increased energy density would expand the possibilities for electric aircraft.  Imagine some of the recently introduced trainers with three-hour cruising capabilities.

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WATTsUP at Pipistrel

No, that’s a statement and not a question.  Taja Boscarol of Pipistrel sent the following announcement this morning.  WATTsUP, their new two-seat electric trainer took its maiden flight on August 8th.  As part of its 25th anniversary celebrations, Pipistrel will display the airplane at the Salon de Blois airshow, France, on 30-31 August 2014.

Looking a great deal like the Pipistrel Alpha trainer, WATTsUP makes its maiden flight

Looking a great deal like the Pipistrel Alpha trainer, WATTsUP makes its maiden flight

This is the third announcement of an electric trainer by a major aircraft manufacturer, counting Airbus with its anticipated e-Fan developments and American Electric Aircraft Corporation (AEAC) with its Sun Flyer.  We could count four with Adventure Aircraft’s EMG-6 under development in California for the ultralight market.  This would mark a potentially historic turnaround for General Aviation, with promised operating costs significantly lower than for internal-combustion powered machines, and by inference, lower rental costs for student pilots.

One of the most exciting parts of the announcement – the price: “Pipistrel expects to bring the final product to the market in 2015 with a target price below 100,000 EUR ($135,000),” according to their press release. Sun Flyer and e-Fans are also expected to be within the upper range of Light Sport Aircraft prices, making for a potentially competitive and technologically rich new market segment.

Siemens, a partner in the endeavor, may also supply the electric motor and other components for the Hypstair (anyone notice a Slovenian tendency to pun?), the hybrid version of the Pipistrel Panthera.  With two motors in the 85 kilowatt (114 horsepower) and 150 kW (201 hp. continuous) ranges, Siemens seems dedicated to becoming a participant in this new area.   The 85 kW motor weighs only 14 kilograms (30.8 pounds), more powerful and much lighter than the Rotax 912 series engines typically found on microlights and LSAs.  It’s heartening that the motor is being built by Siemens, 53rd on the Forbes’ list of the Global 2,000 companies.  For comparison, General Motors is 67th on the list.

Siemens 85 kW motor takes up little space under the cowling

Siemens 85 kW motor takes up little space under the cowling

Much of that weight savings will be offset by the 17-kilowatt-hour battery, a “dual-redundant” package that can be swapped in a few minutes or recharged in less than an hour, “thanks to the next generation of Pipistrel’s Battery Management technology.”  The motor/battery combination will give an hour’s endurance with a 30-minute reserve.  Tailored for flight schools, WATTsUP will take off quickly, climb at over 1000 feet-per-minute, and, it’s claimed, recover 13 percent of the energy from every approach.  Tine Tomazic, the company’s Chief Designer, emphasized at last year’s Electric Aircraft Symposium that regeneration would depend on a steep descent and a special training regimen for students learning in the electric trainer.

Propeller on WATTsUP seems to follow design concepts of Jack Norris, who holds 50 NASA patents

Propeller on WATTsUP seems to follow design concepts of Jack Norris, who holds 50 NASA patents, may contribute to regeneration on approach

Because it’s based on existing Pipistrel airframes, Ivo Boscarol, CEO of Pipistrel, may be correct in saying: “With the ever growing cost of fuel it is time to rethink pilot training. Our solution is the first practical all-electric trainer!”  As do AEAC and Airbus, he advocates the economy of operation for the craft.  “Technologies developed specially for this aircraft cut the cost of ab-initio pilot training by as much as 70 percent, making flying more affordable than ever before. Being able to conduct training on smaller airfields closer to towns with zero C02 emissions and minimum noise is also a game changer! WATTsUP meets microlight and ASTM LSA criteria, as well as standards for electric propulsion and is already certified in France. More countries will follow soon and we are applying for an exemption with the FAA to allow training operations as an S-LSA. WATTsUP is our 5th electric aircraft project and the second to result in a commercial product.”

Frank Anton, Executive Vice President Traction Drives, Large Drives, Siemens AG is quoted as saying: “Siemens is developing electric drive systems with highest power-to-weight ratio for aircraft propulsion. Only with innovation we can solve the problems of rising fuel costs, rising passenger demand and rising environmental regulations.  Innovations used in the WATTsUP will be instrumental in making aviation more sustainable in the long run. As electric drives are scalable, we can expect that in the future also larger aircraft will use electric propulsion. The world is becoming electric, whether in the air, on land or at sea.”

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