producing hydrogen just got more promising

The UCLA device is a hybrid unit that combines a supercapacitor with a hydrogen fuel cell, and runs the whole shebang on solar power. Along with the usual positive and negative electrodes, the device has a third electrode that can either store energy electrically or use it to split water into its constituent hydrogen and oxygen atoms – a process called water electrolysis. To make the electrodes as efficient as possible, the team maximized the amount of surface area that comes into contact with water, right down to the nanoscale. That increases the amount of hydrogen the system can produce, as well as how much energy the supercapacitor can store. Read more here; .....https://newatlas.com/solar-hydrogen-electricity-device/52329/

Liquid metal feeds Stanford's new high-voltage flow battery

First and foremost, the fluid used as the negative side of the battery is an alloy of sodium and potassium. This mixture remains a liquid metal at room temperature, and theoretically packs at least 10 times the energy density of other fluids previously suggested for the role. On the positive side of the cell, the team tested four different water-based liquids. The second new material is in the membrane used inside the cell. The team made a ceramic membrane out of potassium and aluminum oxide, which keeps the positive and negative fluids separate while still allowing current to flow between them. The combination of the new anolyte and the new membrane, reportedly produces twice the maximum voltage of other flow batteries, which means a better overall energy density and lower production cost. The prototype the team developed also proved its stability over thousands of hours of operation. full story is here; https://newatlas.com/liquid-metal-flow-battery/55545/

EE stor still making claims with ultra capacitor storage!

At least the claims are still alive, but doubts have simmered since like, forever... there is a blog which has documented the claims since ... https://bariumtitanate.blogspot.com/ here is a paragraph from it; It was recently proposed to me that possibly in the near term, I could take a tour of EEStor's facility. Five years ago that would have been a dream come true but today, I don't really think I could work it into my schedule. If I had to listen to Dick Weir's un-decypherable bullshit, I'd probably lose my lunch. As for stressing over EEStor and looking for what's next, those days are way behind us and from my perspective, the whole thing has become a colossal waste of time and distraction. To get to the heart of things, this blog has become to me personally a recurring set of disappointing developments. It's impacted me emotionally and I used to be able to counterbalance that with enjoyment from the community that built up around EEStor. But that community has always been dwindling as it should from EEStor's failure to deliver on their self-set goals. On top of this, I think eight years of emotional disappointment is just too much to continue to slow brew. I have a lot of other things I want to accomplish in my life and maintaining a scientific debate community is no longer one of them. It is just too distracting so take this for what it is: a bit of Spring cleaning in my life and my attempt to get my focus back. So of course, no one will be satisfied with how this all ends up. But in keeping with how I've done things from the beginning, I will end with some of my personal speculations and issue some new predictions. First, I believe Carl Nelson worked on a team at MIT under Arthur Von Hippel that discovered a capacitor effect which had off the charts measurements--an effect whose limits were not apparent to them then or to EEStor now. I believe the MIT team couldn't control the effect with the manufacturing methods available at the time and had bigger fish to fry with the development of the digital age. That digital age improved manufacturing methods and at some point Dick Weir and Carl Nelson set out to see if they could bring about the effect originally discovered at MIT. Weir's ambitions were bigger than his technical ability and extreme narcissism drove Nelson out of the picture and left the technical development in uncertain hands. To make matters worse, the controls Weir and team thought they had over the material turned out to be illusory. What's left now is the possibility that the effects which are controllable are commercializable as well. another comment then there is the discussion on revolution green, http://revolution-green.com/battery-breakthrough-battery-ultra-capacitor-breakthrough-hybrid-game-changer-te-scene/, a bit of chronology; from Asterix • 20 days ago EEStor again? I've written here years ago about their charade. Zenn Cars, originally called "Feel Good Cars" (ZENN was just a model) paid a scam artist with his company AEC (Alternate Energy Corporation) who essentially promised a car that ran on water. The name of FGC's CEO at the time? One Ian Clifford. Later FGC changed their name to ZENN Cars and teamed up with another snake-oil specialist, Richard Weir and his company EEStor, who promised a high-capacity, high-voltage capacitor with an energy density exceeding that of current electrochemical batteries. The gotcha was that Weir never produced complete working units, only layers, which were "verified" under Weir's control. ZENN floated a bunch of stock on the TSX Venture exchange and got a few private venture capitalists (e.g. Kleiner Perkins) involved. Oh--the executive involved in the deal? One Ian Clifford. After years of delivering nothing, EEStor, in a rather complicated game, gained control of ZENN. The last I heard, the unremarkable product of all of this dreaming was a capacitor that may or may not compete with traditional ceramic capacitors. Some invested their retirement nest egg in the venture and lost it. At the last check, EEStor stock was at 0.18 CAD. Rossi has shown his acumen by carrying on his scam for far longer. Both seem to have some believers left, though heaven knows why. EEStor’s system–called an Electrical Energy Storage Unit, or EESU–is based on an ultracapacitor architecture that appears to escape the traditional limitations of such devices. The company has developed a ceramic ultracapacitor with a barium-titanate dielectric, or insulator, that can achieve an exceptionally high specific energy–that is, the amount of energy in a given unit of mass. For example, the company’s system claims a specific energy of about 280 watt hours per kilogram, compared with around 120 watt hours per kilogram for lithium-ion and 32 watt hours per kilogram for lead-acid gel batteries. This leads to new possibilities for electric vehicles and other applications, including for the military. “It’s really tuned to the electronics we attach to it,” explains Weir. “We can go all the way down from pacemakers to locomotives and direct-energy weapons.” The trick is to modify the composition of the barium-titanate powders to allow for a thousandfold increase in ultracapacitor voltage–in the range of 1,200 to 3,500 volts, and possibly much higher. EEStor claims that, using an automated production line and existing power electronics, it will initially build a 15-kilowatt-hour energy-storage system for a small electric car weighing less than 100 pounds, and with a 200-mile driving range. The vehicle, the company says, will be able to recharge in less than 10 minutes.

Reawakening, Sweden - 4K UHD

Toyota still working on hydrogen, now also in heavy trucks

Hydrogen and batteries both carry an environmental cost that means neither can be called entirely green. For all the piety surrounding BEVs, current battery-manufacturing processes mean that, during construction, they're almost as bad for the environment as traditional cars. It's only when they're out on the road that the situation begins to improve. The majority of hydrogen is not created using renewables, either, but is mass-produced with steam-methane reforming. The system uses natural gas (not renewable) and high-temperature steam to create carbon monoxide and hydrogen. Steam reforming means that you're left with a big pile of carbon monoxide to deal with, but that methane also has a tendency to leak. It can escape from both the factory, when it is created, and from the pipelines used to transport it, and methane is one hundred times more damaging to the climate than CO2. Decarbonizing the economy will be for nothing if these leaks aren't brought under control or stopped completely. With that in mind, Shell is building an electrolysis plant on the side of an existing steam-methane reformer. The company is aiming to get a 50/50 split on the balance of green hydrogen it can produce, although van Els hopes that figure can reach 80 percent in the longer term. SONY DSC The problem "has to be dealt with," said Thomas Hwan Jensen, a policy adviser at Energinet, the body that owns Denmark's gas and electricity transmission system. "Methane leakage is being addressed," he added, showing that the energy companies at least understand the issue. If there are positives, it's that there are systems in place that could mitigate some of the damage caused by carbon dioxide. Denmark's BioCat Project (pictured), for instance, uses a biological process to turn carbon dioxide and hydrogen into synthetic natural gas for use in power stations. It's still emissions-heavy, but, if powered by renewable energy, it could be a better way to generate power than, say, more coal-fired stations. Of course, any solution that doesn't involve burning fossil fuels is better for the environment; this isn't any defense of the oil industry. It's just important to understand that there is no wonder fuel that is entirely free from downsides. Hydrogen's ideal place seems to be in medium-size vehicles, where the trips are long and the loads are heavy. Fleet vehicles, mid-range sedans, SUVs, vans, trucks and trains could all benefit from a shift in fuel. After all, it can be stored similarly to gasoline, with a better energy density, and is theoretically cheaper than bulky batteries. Alstom is working on a hydrogen train that could replace diesel-powered fleets across the globe as a far cheaper alternative to rail electrification. Toyota is already running a hydrogen-powered big rig out of the port of Los Angeles, called Project Portal. NEL Hydrogen's Lars Jacobsen said that the fuel cell technology is "mature" enough for use in heavier industry. He added that, while "cars are fantastic, they don't make the business case" (for it). It's his belief that it's in trucking that hydrogen will make the biggest initial impact, and his company is already working with Nikola Motors. Nikola has secured a pretty extraordinary deal with brewer Anheuser-Busch, which has pre-ordered $9 billion worth of hydrogen trucks. Eight hundred vehicles are expected to be pressed into service, starting in 2020, each one capable of traveling 1,200 miles before refueling. The trucks could serve as the catalyst for a new, America-wide hydrogen-refueling network, with 700 stations anticipated, which would hopefully encourage the production of more hydrogen-powered consumer vehicles. Meanwhile, is there a place for hydrogen in the aerospace industry? The image of the Hindenburg engulfed in flames remains a powerful one, even today. Hamburg's Center of Applied Aeronautical Research has already found that it would be feasible to build a drone plane fueled by hydrogen. Airbus, too, is looking at ways to incorporate hydrogen into the aircraft of the future, in place of kerosene, although such a decision would require all aircraft to be radically redesigned. via: https://www.engadget.com/2018/05/29/hydrogen-fuel-cell-toyota-mirai-evs/

redox flow tech using vanadium

found this on the website of http://www.storen.tech/copia-di-products StorEn VFBs are based on years of creativity and lateral thinking of the StorEn Technical Team in Fuel Cells, Vanadium Flow Batteries and cogeneration. StorEn modules utilize a proprietary electrolyte chemistry that delivers an increased energy density of the modules in the region of +25%. Furthermore, they embed a patent-pending stack design reducing by over 50% the cost of the power side of the battery. The standard long 20-year duration typical of Vanadium Flow Batteries can be exceeded thanks to a patent-pending innovation that extends duration of StorEn batteries to over 15,000 cycles, extending service intervals and reducing maintenance costs. The result of StorEn R&D activities are modules with the highest power and energy density, a modular architecture to satisfy the widest array of customers’ installations requirements, and the lowest Total Cost of Ownership possible today.

redox flow battery Elestor

In addition to the intrinsic advantages related to HBr electricity storage, Elestor has developed a unique HBr storage system concept (patent pending), whereby the full focus has been on minimizing the cost per stored kWh. Each individual system quality (lifetime, no. of (dis)charge cycles, efficiency/cycle, material costs, production costs) contributes to the total cost per stored kWh. In this number, also known as the ‘Levelized Cost of Storage’ [€/kWh], every system quality is taken into account. Minimizing the costs per stored kWh By minimizing manufacturing cost and at the same time optimizing the performance of each system quality, Elestor managed to reduce the total costs per stored kWh. To accomplish this milestone, Elestor has introduced several new technical developments, resulting in: Long system lifetime » Over 10.000 charge/discharge cycles High system efficiency » 80% per complete charge/discharge cycle Low material costs » Abundant availability of Br2 and H2 Low production costs » No H2 compressor required » Smart production procedures » Innovative and simplified – yet robust - system architecture Flow plates End plates Storage system versus battery pack The Elestor storage solution is to be considered a machine rather than a closed battery pack: All parts, circulation pump, valves, electrochemical cells and control electronics, are easily accessible. In contrary to closed battery packs, Elestor’s storage systems can always be repaired, serviced and upgraded, which further prolongs the systems’ already long lifetime, leads to a further reduction of storage costs per kWh, and further enhances the return on investment. As a result, Elestor presents an innovative HBr – based storage system, showing a cost of as low as € 0,05 per kWh. With this cost-level, the Elestor HBr storage system has become the new benchmark in electricity storage technology. www.Elestor.nl

Yet another contender in the battery tech; Proton

A team from Australia's from RMIT University in Melbourne have figured it out to build rechargeable "proton" batteries from abundant carbon and water. If commercialized, the technology could allow for cheaper Powerwall-type home or grid storage to back up solar panels or windmills.During charging, water is split to produce protons, which then pass through a cell membrane and bond to the carbon electrodes, without producing hydrogen gas. To tap the stored energy, the hydrogen ions are released and lose an electron to re-form the protons. The electrons supply power, while the hydrogen protons combine with oxygen and other electrons to re-form into water. The big advantage with proton batteries compared to fuel cells is efficiency. The latter must produce hydrogen gas then split it back into protons, which creates losses. But a proton battery never produces hydrogen gas, so the energy efficiency is comparable to lithium-ion batteries. And even though the system is far from optimized, energy density is also comparable to lithium ion, the team said. The researchers built a small, 1.2 volt battery, so the next step is to scale it up and improve efficiency. "Future work will now focus on further improving performance and energy density through use of atomically-thin layered carbon-based materials such as graphene, with the target of a proton battery that is truly competitive with lithium ion batteries firmly in sight," said lead researcher Professor John Andrews. https://www.engadget.com/2018/03/09/proton-battery-carbon-water-no-lithium/?utm_source=spotim&utm_medium=spotim_recirculation&spotim_referrer=recirculation

10 SOLAR-POWERED HOMES | THE FUTURE OF ARCHITECTURE

A green megabattery for green energy using brine underground

(Tech Xplore)—A company has an ambitious plan: To build the world's largest battery. Germany is the hatching grounds. Ewe Gasspeicher, subsidiary of utility company Ewe, is talking about its plan with an approach that centers around the redox flow battery principle. This is where electrical energy is stored in liquid in which certain chemicals are dissolved. These solutions are called electrolytes. The battery will have components based on salt water and recyclable plastics and developed by the Friedrich Schiller University Jena. "Electrolytes previously used included environmentally polluting salts of heavy metals such as vanadium dissolved in sulphuric acid. The Friedrich Schiller University in Jena has now developed a redox flow battery that uses recyclable polymers (plastics) dissolved in salt water as an electrolyte." "Ewe says its invention is a 'green megabattery for green energy,'" wrote Global Construction Review. The plans call for the world's biggest battery using redox flow technology in underground salt caverns usually used for natural gas storage. Electrical energy would be stored in a liquid along with "new" components in the underground salt caverns currently used for storing natural gas. Two caverns, each with a volume of 100,000 m³, will be used for the battery. The components are the result of the collaboration with the Friedrich Schiller University in Jena, which developed them. "'Since salt water in caverns is also known as brine and we intend to store power according to the redox flow principle, we have named the project brine4power, or b4p for short,' said project manager Ralf Riekenberg." According to Global Construction Review, Riekenberg said he assumed they may have a cavern battery in operation at the end of 2023. Initially, they will not be using actual caverns but enormous plastic containers, said the news release. These will be set up at the gas storage facility in Jemgum in East Frisia, probably in the fourth quarter of this year. Ewe Gasspeicher GmbH Managing Director, Peter Schmidt: "If everything works, this may fundamentally change the storage market, i.e. the market for control energy." "Once built," said Global Construction Review, "the batteries would be used to increase the stability of the German grid, thereby allowing it to accept a higher percentage of intermittent generators." An EW site said that "brine4power is the project for cost-effective, safe and sustainable power storage. In combination with a suitably sized wind farm, each battery replaces a controllable 120-megawatt power plant, supplying constant and clean energy at consistent prices." If it works, Ewe Gasspeicher will create a 700MWh battery, said Global Construction Review. Lulu Chang in Digital Trends: "All these caves have a volume of 3.5 million cubic feet, which ought to give the resulting battery a capacity of up to 700MWh at an output of 120MW." Chang said if it works, the battery ought to be able to supply 75,000 homes with their power for a day. "While bulkier than lithium-ion battery systems, redox flow systems do not degrade through heavy charge and discharge cycles, meaning they are expected to last many years longer in the field," commented Energy Storage News. https://techxplore.com/news/2017-07-germany-ambitious-battery-housed-underground.html

Lithium-Ion Battery Inventor Introduces Fast-Charging, Noncombustible Batteries

A team of engineers led by 94-year-old John Goodenough, professor in the Cockrell School of Engineering at The University of Texas at Austin and co-inventor of the lithium-ion battery, has developed the first all-solid-state battery cells that could lead to safer, faster-charging, longer-lasting rechargeable batteries for handheld mobile devices, electric cars and stationary energy storage. Goodenough’s latest breakthrough, completed with Cockrell School senior research fellow Maria Helena Braga, is a low-cost all-solid-state battery that is noncombustible and has a long cycle life (battery life) with a high volumetric energy density and fast rates of charge and discharge. The engineers describe their new technology in a recent paper published in the journal Energy & Environmental Science. “Cost, safety, energy density, rates of charge and discharge and cycle life are critical for battery-driven cars to be more widely adopted. We believe our discovery solves many of the problems that are inherent in today’s batteries,” Goodenough said. The researchers demonstrated that their new battery cells have at least three times as much energy density as today’s lithium-ion batteries. A battery cell’s energy density gives an electric vehicle its driving range, so a higher energy density means that a car can drive more miles between charges. The UT Austin battery formulation also allows for a greater number of charging and discharging cycles, which equates to longer-lasting batteries, as well as a faster rate of recharge (minutes rather than hours). Today’s lithium-ion batteries use liquid electrolytes to transport the lithium ions between the anode (the negative side of the battery) and the cathode (the positive side of the battery). If a battery cell is charged too quickly, it can cause dendrites or “metal whiskers” to form and cross through the liquid electrolytes, causing a short circuit that can lead to explosions and fires. Instead of liquid electrolytes, the researchers rely on glass electrolytes that enable the use of an alkali-metal anode without the formation of dendrites. The use of an alkali-metal anode (lithium, sodium or potassium) — which isn’t possible with conventional batteries — increases the energy density of a cathode and delivers a long cycle life. In experiments, the researchers’ cells have demonstrated more than 1,200 cycles with low cell resistance. Additionally, because the solid-glass electrolytes can operate, or have high conductivity, at -20 degrees Celsius, this type of battery in a car could perform well in subzero degree weather. This is the first all-solid-state battery cell that can operate under 60 degree Celsius. Braga began developing solid-glass electrolytes with colleagues while she was at the University of Porto in Portugal. About two years ago, she began collaborating with Goodenough and researcher Andrew J. Murchison at UT Austin. Braga said that Goodenough brought an understanding of the composition and properties of the solid-glass electrolytes that resulted in a new version of the electrolytes that is now patented through the UT Austin Office of Technology Commercialization. The engineers’ glass electrolytes allow them to plate and strip alkali metals on both the cathode and the anode side without dendrites, which simplifies battery cell fabrication. Another advantage is that the battery cells can be made from earth-friendly materials. “The glass electrolytes allow for the substitution of low-cost sodium for lithium. Sodium is extracted from seawater that is widely available,” Braga said. Goodenough and Braga are continuing to advance their battery-related research and are working on several patents. In the short term, they hope to work with battery makers to develop and test their new materials in electric vehicles and energy storage devices. This research is supported by UT Austin, but there are no grants associated with this work. The UT Austin Office of Technology Commercialization is actively negotiating license agreements with multiple companies engaged in a variety of battery-related industry segments. http://www.engr.utexas.edu/news/8203-goodenough-batteries

Broadbit introduces sodium battery

BroadBit is a technology company developing revolutionary new batteries using novel sodium-based chemistries to power the future green economy. We have already made high performance lab samples and are now commercializing the technology for next generation electric vehicles, portable electronics, starters and grid energy storage. Our batteries enable: Increased range/use time Longer lifetime Reduced cost Improved environmental friendliness Scalable to any production volume The batteries are based on metallic sodium and other widely available and plentiful compounds. Our active materials include sodium chloride (NaCl), which is also known as table salt. BroadBit is also developing a high power and low cost battery capable of fully recharging in 5 mins! Transportation Our batteries enable longer range electric vehicles. We eliminate range anxiety and make electric vehicles competitive in price. Engine Starters Our batteries provide increased durability for starter applications. We eliminate dead batteries due to cold temperature or over discharging. Portable Electronics Our batteries allow electronics such as laptop computers, sensors, and flashlights to be lighter and last longer between charges. Backup Power Our batteries enable cheaper and smaller energy storage systems for backup power applications. http://www.broadbit.com

BroadBit has invented and is commercializing a new type of metallic sodium battery in two families: Hi-Energy batteries with twice the energy per weight and Hi-Power batteries with ten times the power as todays lithium-ion batteries. BroadBits Hi-Power batteries can be fully charged in as little as 5 minutes. BroadBits batteries are made with abundant and cheap raw materials (e.g. table salt) and its manufacturing process is simpler than Li-ion. With these advantages, BroadBit expects its cost per kWh to be a third that of Li-ion when in mass production. Moreover, initial tests of the technology show no detectable degradation in battery performance over 600 cycles. This is because, unlike Li-ion, there are no side reactions, dendrite formation or mechanical stress due to ion intercalation. These innovations, if BroadBit can turn them into mass production and meet their promises, could make mobile devices lighter, faster charging and longer lasting and will finally enable low-cost, high range and convenient electric vehicles including cars, buses, bikes and even electric air planes and bring about the long awaited post combustion era of transportation. BroadBit is now scaling production of its proprietary electrolytes, anodes and cathodes and is looking for partners worldwide to assemble batteries from its components. Tech reloaded You can contact BroadBit here: david.brown@broadbit.com

Graphene polymer battery offers high energy density, safety and fast charging

A collaboration between Graphenano and its Chinese partner Chint has led to a graphene battery that surpasses any current lithium ion battery, and it could soon replace batteries in domestic use and electric cars. POWERING THE FUTURE The Spanish company Graphenano has introduced a graphene polymer battery that could allow electric vehicles to have a maximum range of a staggering 800 kilometers (497 miles). The battery can also be charged in just a few minutes. And it could do more than revolutionize electric cars. The company notes that the battery is designed for a number of uses, and could be put in houses, bicycles, drones, and even pacemakers. Dubbed Grabat, the batteries will be manufactured in Yecla, Spain and will have an energy density of 1,000 Wh/kg (for comparison, lithium batteries generally have a energy density of 180 Wh/kg). Grabat will also have a voltage of 2.3 V. If that’s not enough, the battery could discharge and charge faster than a standard lithium ion battery (almost 33 times that of lithium). It also does not exhibit memory effect, a phenomenon in which charging a battery multiple times lowers its maximum energy potential. Best of all, independent analyses by TÜV and Dekra have demonstrated that the batteries are safe and are not prone to explosions like lithium batteries, and tests conducted by the company have shown that, after being short-circuited, the battery is able to return to work with 60% of the load. GOING THE EXTRA MILE If you haven’t heard of this wonder material, graphene is a nanomaterial that is just one atom thick. It is amazingly hard, yet flexible and elastic. It has long been known that graphene has very high thermal and electrical conductivity. It’s also light and produces electricity after being hit by light. The company expects to have prototypes as early as mid-2016, with commercial batteries being produced by the end of the year. They project that, by 2019, they will have made a turnover of 3,000-4,000 million euros. If Grabat does become a success, and powers the next Tesla, reaching that figure doesn’t seem so far-fetched.

Aquion Energy's Salt water batteries returns to the market in 2018

Since March of this year the Aquion Energy’s Pittsburgh Pennsylvania based R&D and Engineering teams have been working to improve upon the chemistry and quality of the original Aquion S-Line/Aspen battery stack. Improvements will include a boost to the energy density of the stack, continued improvements to cycle life and lifetime capacity degradation all while using the same materials that make Aquion Energy batteries the safest and most sustainable batteries on the market. It was this commitment to safety, sustainability, and a portfolio of projects across the globe which attracted a large US capital private equity fund to acquire Aquion Energy. This fund has allowed Aquion Energy to emerge out of the restructuring period in just three months since the company filed for Chapter 11 protection. With capital funding now secure, Aquion can confidently re-enter the market with expanded global manufacturing capabilities. Ultimately these capabilities will result in some of the most competitive acquisition and operational costs in the energy storage industry.

A thermoelectric material (ytterbium silicide) with a high power factor at room temperature

Osaka University-led researchers create a thermoelectric material (ytterbium silicide) with a high power factor at room temperature

(a) Three-dimensional crystal structure of YbSi2, (b) view along the a-axis, and (c) along the c-axis. CREDIT: © 2017 Kurosaki et al. Phys. Status Solidi RRL 2017, 1700372. doi: 10.1002/pssr.201700372

IMPROVED POWER FACTOR AT ROOM TEMPERATURE

Thermoelectric (TE) materials could play a key role in future technologies. Although the applications of these remarkable compounds have long been explored, they are mostly limited to high-temperature devices. Recently, researchers at Osaka University, in collaboration with Hitachi, Ltd., developed a new TE material with an improved power factor at room temperature. Their study, published in Physica Status Solidi RRL, could help bring these materials out of the high-temperature niche and into the mainstream.

TE materials display the thermoelectric effect: apply heat on one side, and an electric current starts to flow. Conversely, run an external current through the device, and a temperature gradient forms; i.e., one side becomes hotter than the other. By interconverting heat and electricity, TE materials can be used as either power generators (given a heat source) or refrigerators (given a power supply).

The ideal TE material combines high electrical conductivity, allowing the current to flow, with low thermal conductivity, which prevents the temperature gradient from evening out. The power generation performance mainly depends on the “power factor,” which is proportional to both electrical conductivity and a term called the Seebeck coefficient.

“Unfortunately, most TE materials are often based on rare or toxic elements,” according to study co-author Sora-at Tanusilp. “To address this, we combined silicon – which is common in TE materials – with ytterbium, to create ytterbium silicide [YbSi2]. We chose ytterbium over other metals for several reasons. First, its compounds are good electrical conductors. Second, YbSi2 is non-toxic. Moreover, this compound has a specific property called valence fluctuation that make it a good TE material at low temperatures.”

The first advantage of YbSi2 is that the Yb atoms occupy a mixture of valence states, both +2 and +3. This fluctuation, also known as Kondo resonance, increases the Seebeck coefficient with keeping metal-like high electrical conductivity at low temperature, and therefore the power factor.

Second, YbSi2 has an unusual layered structure. While the Yb atoms occupy crystal planes similar to pure Yb metal, the Si atoms form hexagonal sheets between those planes, resembling the carbon sheets in graphite. This blocks the conduction of heat through the material, and therefore keeps the thermal conductivity down, preserving the temperature gradient. The researchers believe that heat conduction is further suppressed by controlling the structure in nanoscale and traces of impurities and other defects.

The result is an encouragingly high power factor of 2.2 mWm-1K-2 at room temperature. This is competitive with conventional TE materials based on bismuth telluride. As corresponding author of this study Ken Kurosaki explains, “The use of Yb shows we can reconcile the conflicting needs of TE materials through carefully selecting the right metals. Room-temperature TEs, with moderate power, can be seen as complementary to the conventional high-temperature, high-power devices. This could help unlock the benefits of TE in everyday technology.

Bicycle lights without batteries or drag from generator/dynamo

Credit:   Luke Dormehl  Digital Trends December  28, 2017

When it comes to lights, cyclists typically have one of two options: Either a battery-powered light which needs replacing every so often or a dynamo-powered light which uses the spinning of your bike’s wheels to generate power, but which cause friction that can slow you down. A new Kickstarter campaign 

https://www.kickstarter.com/projects/dynamodirk/magnic-microlights-non-contact-driven-brake-shoe-b?

seems to offer a perfect third solution, however: Smart brake lights that work courtesy of a completely contactless dynamo-powered battery. The promise? Endless light without resistance — via so-called eddy currents, loops of electrical current induced within conductors thanks to a changing magnetic field.

“When faced with Magnic Light for the first time, many believe that this is either a fake or a perpetual motion generator,” inventor Dirk Strothmann told Digital Trends. “Both aren’t true, but the underlying eddy current technology is so fascinating because the magnetic fields only appear when there is motion — in our case the rotating rim. By hiding a rotating magnet wheel inside a black box, the perpetual motion illusion is perfect. But in our case, this is more than a magic trick because this concept has several advantages over standard dynamos: an air gap between wheel and generator means no problems with dirt, rain or snow, and an encapsulated unit without external cables is better protected and feels like a battery light that is never empty.”

Magnic Microlights: Non-contact driven brake shoe bike light

In addition to excellent illumination, Strothmann has also created smart versions of the brake lights which offer a turn signal that’s triggered via a quick double pump of the brake handle, alongside smartphone-controlled navigation signals and sensor-free speed tracking.

Strothmann is no stranger to Kickstarter. He has two successful Kickstarter campaigns he has delivered in the past, which means that people willing to stump up some pre-order cash aren’t doing so on an unproven entity. If you would like to get hold of some of his new lights, you can currently place an order on Kickstarter, where he is selling a set of both the smart new rear lights and also front lights for 99 euros (around $118). Other price options are also available — including a basic set of front and rear lights for a frankly ridiculous $1.20 (!!) for the first 1,000 people to sign up. Shipping is set to take place in November 2018