NREL, Swiss Scientists Power Past Solar Efficiency Records

NREL scientist Adele Tamboli, co-author of a recent article on silicon-based multijunction solar cells, stands in front of an array of solar panels. Credit: Dennis Schroeder

August 25, 2017

Second collaborative effort proves silicon-based multijunction cells that reach nearly 36% efficiency

Collaboration between researchers at the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL), the Swiss Center for Electronics and Microtechnology (CSEM), and the École Polytechnique Fédérale de Lausanne (EPFL) shows the high potential of silicon-based multijunction solar cells.

The research groups created tandem solar cells with record efficiencies of converting sunlight into electricity under 1-sun illumination. The resulting paper, “Raising the One-Sun Conversion Efficiency of III–V/Si Solar Cells to 32.8% for Two Junctions and 35.9% for Three Junctions,” appears in the new issue of Nature Energy. Solar cells made solely from materials in Groups III and V of the Periodic Table have shown high efficiencies, but are more expensive.

Stephanie Essig, a former NREL post-doctoral researcher now working at EPFL in Switzerland, is lead author of the newly published research that details the steps taken to improve the efficiency of the multijunction cell. While at NREL, Essig co-authored “Realization of GaInP/Si Dual-Junction Solar Cells with 29.8% 1-Sun Efficiency,” which was published in the IEEE Journal of Photovoltaics a year ago.

In addition to Essig, authors of the new research paper are Timothy Remo, John F. Geisz, Myles A. Steiner, David L. Young, Kelsey Horowitz, Michael Woodhouse, and Adele Tamboli, all with NREL; and Christophe Allebe, Loris Barraud, Antoine Descoeudres, Matthieu Despeisse, and Christophe Ballif, all from CSEM.

“This achievement is significant because it shows, for the first time, that silicon-based tandem cells can provide efficiencies competing with more expensive multijunction cells consisting entirely of III-V materials,” Tamboli said. “It opens the door to develop entirely new multijunction solar cell materials and architectures.”

In testing silicon-based multijunction solar cells, the researchers found that the highest dual-junction efficiency (32.8%) came from a tandem cell that stacked a layer of gallium arsenide (GaAs) developed by NREL atop a film of crystalline silicon developed by CSEM. An efficiency of 32.5% was achieved using a gallium indium phosphide (GaInP) top cell, which is a similar structure to the previous record efficiency of 29.8% announced in January 2016. 

A third cell, consisting of a GaInP/GaAs tandem cell stacked on a silicon bottom cell, reached a triple-junction efficiency of 35.9%—just 2% below the overall triple-junction record.

The existing photovoltaics market is dominated by modules made of single-junction silicon solar cells, with efficiencies between 17% and 24%. 

The researchers noted in the report that making the transition from a silicon single-junction cell to a silicon-based dual-junction solar cell will enable manufacturers to push efficiencies past 30% while still benefiting from their expertise in making silicon solar cells.

The obstacle to the adoption of these multijunction silicon-based solar cells, at least in the near term, is the cost. Assuming 30% efficiency, the researchers estimated the GaInP-based cell would cost $4.85 per watt and the GaAs-based cell would cost $7.15 per watt. 

But as manufacturing ramps up and the efficiencies of these types of cells climbs to 35%, the researchers predict the cost per watt could fall to 66 cents for a GaInP-based cell and to 85 cents for the GaAs-based cell. 

The scientists noted that such a precipitous price drop is not unprecedented; for instance, the cost of Chinese-made photovoltaic modules fell from $4.50 per watt in 2006 to $1 per watt in 2011.

The cost of a solar module in the United States accounts for 20% to 40% of the price of a photovoltaic system. Increasing cell efficiency to 35%, the researchers estimated, could reduce the system cost by as much as 45 cents per watt for commercial installations. 

However, if the costs of a III-V cell cannot be reduced to the levels of the researchers’ long-term scenario, then the use of cheaper, high-efficiency materials for the top cell will be needed to make them cost-competitive in general power markets.

The funding for the research came from the Energy Department’s SunShot Initiative—which aims to make solar energy a low-cost electricity source for all Americans through research and development efforts in collaboration with public and private partners—and from the Swiss Confederation and the Nano-Tera.ch initiative.

NREL is the U.S. Department of Energy’s primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for the Energy Department by The Alliance for Sustainable Energy, LLC.

We May Finally Have a Way to Cheaply Manufacture Pure Graphene

Synthesizing Pure Graphene

Researchers have been singing the praises of graphene ever since it was first isolated from graphite back in 2004. That’s not terribly surprising given the unique properties the two-dimensional material possesses. Graphene has since proven useful for everything from superconductors to microchips to tougher-than-steel rubber bands, but despite the wealth of research, manufacturing graphene for large-scale commercial use has remained problematic — the process is simply too costly and complicated.

University of Connecticut chemistry professor Doug Adamson might be able to change that. He and his colleagues have figured out a cost-effective way to synthesize this wonder material, and perhaps best of all, Adamson claims his method synthesizes graphene in its pure, unoxidized form. The research has been published in ACS Nano.

Watch More: Super Materials of Tomorrow – Graphene

Adamson’s method takes advantage of one of graphene’s typically undesirable characteristics: its insolubility to most solvents. After placing graphite in an interface of water and oil, the material spreads spontaneously to cover the interface. There, it becomes trapped in individual, overlapping graphene sheets that can be locked in place using plastic or other cross-linked polymers.

“The innovation and technology behind our material is our ability to use a thermodynamically driven approach to un-stack graphite into its constituent graphene sheets, and then arrange those sheets into a continuous, electrically conductive, three-dimensional structure,” Adamson explained in a UConn press release.

Its Best Behavior

The “graphene” most researchers use in their studies is an oxidized version of the material. Adding oxygen to graphene makes it easier to work with, but it also increases the cost, requires the use of hazardous materials, and adds time to the manufacturing process. It also reduces graphene’s mechanical, thermal, and electrical properties — essentially what makes graphene great.

“The simplicity of our approach is in stark contrast to current techniques used to exfoliate graphite that rely on aggressive oxidation or high-energy mixing or sonication — the application of sound energy to separate particles — for extended periods of time,” Adamson said. “As straightforward as our process is, no one else had reported it. We proved it works.”

Now that Adamson’s team has found a way to produce this pristine graphene, they’re looking forward to potential applications. One of those is desalination. The group created a startup, 2D Material Technologies, that is working on a device that uses their pure graphene and a process known as capacitive deionization (CDI) to remove salt from brackish water.

While much has already been accomplished using graphene, a technique like Adamson’s that can easily be scaled up for the mass production of the material could lead to an explosion of new research and commercial applications. A bit more than a decade after its discovery, all the wonder of graphene could finally be taken advantage of in a meaningful way.

Cummins Beats Tesla To The Punch And Introduces An All-Electric Heavy-Duty Truck

With Tesla purportedly gearing up to introduce an all-electric semi next month, diesel engine supplier Cummins took some of the automaker’s buzz away on Tuesday, revealed an all-electric prototype truck of its own.

Read More: Here’s More Reasons Why We Need Electric Trucks

Billed as a Class 7 Urban Hauler Tractor, the 18,000-pound truck was built by Roush and is geared for local deliveries, according to the Indianapolis Star. The company said it plans to begin selling a 140 kWh battery pack for bus operators and commercial truck fleets in 2019, reports Forbes.

With a claimed range of 100 miles, it certainly seems apt to handle short drives, and Cummins said it only takes an hour to charge. By the time it’s introduced in 2020, Forbes reports, the company hopes to drop that number to 20 minutes. 

A hybrid, with a diesel engine used on-board as a generator, is planned later and will offer 300 miles in range.

Cummins’ chief exec, Thomas Linebarger, told Forbes that electric technology isn’t quite ready for 18-wheelers, mostly due to the long distances they travel. Tesla’s truck will reportedly be set to handle lengthier tasks, with 200 to 300 miles on a single charge, but that remains far below the 1,000 miles a typical heavy-duty truck can handle on one tank of gas.

Cummins may have introduced a prototype truck cab to show off, but the company only intends to produce the powertrain for trucks, Forbes reports.

Nanotechnology delivers medicine to cancer cells while protecting healthy cells ~ “Fooling Cancer”

Cancer treatments, including chemotherapy, have helped many of those who have been diagnosed with the disease to go on to live healthy lives.

Nevertheless, chemotherapy takes a toll on the body. During treatment, chemotherapy attacks all of the body’s cells, not just cancer cells. The result destroys healthy cells, causing many patients to suffer major side effects during and after treatment.

And because current treatments aren’t specifically targeted to cancer cells, only 0.01 percent of chemotherapy drugs actually reach the tumor and its diseased cells.

“I’m working on figuring out how we can deliver more of the chemotherapy drugs to the tumor and less to healthy cells,” says Sofie Snipstad, who recently graduated from the Department of Physics at the Norwegian University of Science and Technology (NTNU). Last year, she won a Norwegian science communication competition for PhD candidates called Researcher Grand Prix. When she made her winning presentation about her research during the competition finals, she was in the middle of testing a new method of cancer treatment on mice.

Now her research has shown that the method can cure cancer in mice.

Her study has just been published in the academic journal Ultrasound in Medicine and Biology (“Ultrasound Improves the Delivery and Therapeutic Effect of Nanoparticle-Stabilized Microbubbles in Breast Cancer Xenografts”).

Blood vessels supplying the cancer cells (kreftceller in the illustration) have porous walls, while the sections of blood vessels passing through healthy cells are not porous. This protects healthy cells from the chemotherapy. (Image: NTNU)

Promising results

Snipstad’s method targets cancerous tumors with chemotherapy so that more of the drug reaches cancer cells while protecting healthy cells. The experiments were conducted in mice with an aggressive breast cancer type (triple negative).

Researchers undertook many laboratory experiments before conducting their tests with mice — which were the first actual tests using this delivery method for chemotherapy. In addition to causing the tumors to disappear during treatment, the cancer has not returned in the trial animals.

“This is an exciting technology that has shown very promising results. That the first results from our tests in mice are so good, and that the medicine does such a good job right from the start is very promising,” Snipstad says.

Here’s how the treatment works

Instead of being injected straight into the bloodstream and transported randomly to both sick and healthy cells, the chemotherapy medicine is encapsulated in nanoparticles. When nanoparticles containing the cancer drugs are injected into the bloodstream, the nanoparticles are so large that they remain in the blood vessels in most types of healthy tissues. This prevents the chemotherapy from harming healthy cells.

Blood vessels in the tumor, however, have porous walls, so that the nanoparticles containing the chemotherapy can work their way into the cancerous cells.

“My research shows that this method allows us to supply 100 times more chemotherapy to the tumor compared to chemotherapy alone. That’s good,” Snipstad says.

However, the nanoparticles can only reach cells that are closest to the blood vessels that carry the drug-laden particles, she said. That means that cancer cells that are far from the blood vessels that supply the tumour do not get the chemotherapy drugs.

“For the treatment to be effective, it has to reach all parts of the tumor. So our nanoparticles need help to deliver the medicine,” she said.

Ultrasound is the key

The nanoparticles used by Snipstad and her research team were developed at SINTEF in Trondheim. SINTEF is one of Europe’s largest independent research organizations. The particles are unusual because they can form small bubbles. The nanoparticles are in the surface of the bubbles.

These bubbles are an important part of the cancer treatment. Another essential part is the use of ultrasound, which is Snipstad’s area of research.

nanobubbles in ultrasound treatments

To make the bubbles behave the way they wanted, the researchers tested many different ultrasound treatments, and measured how many of the nanoparticles were delivered to cancerous tissues in mice. Many of the ultrasound treatments had little effect, but Sofie Snipstad found one that worked quite well. (Image: NTNU)

The bubbles that contain the chemotherapy-laden nanoparticles are injected into the bloodstream. Ultrasound is then applied to the tumor. The ultrasound causes the bubbles to vibrate and eventually burst, so that the nanoparticles are released. The vibrations also massage the blood vessels and tissues to make them more porous. 

This helps push the nanoparticles further into the cancerous tumor, instead of only reaching the cancer cells closest to the blood vessels.

“By using ultrasound to transport the chemotherapy-laden nanoparticles into the tumors, our research on mice has shown that we can deliver about 250 times more of the drug to the tumor compared to just injecting chemotherapy into the bloodstream alone,” she says.

Three groups, three clear results

The mice were divided into three groups:

Group 1 received no treatment, and the tumor continued to grow.

Group 2 received the treatment using drug-laden nanoparticles. The growth of the tumor stagnated after time, but the tumour did not disappear.

Group 3 received the treatment using drug-laden nanoparticles, bubbles and ultrasound. In this group, the tumor shrank until it disappeared. One hundred days after the treatment was discontinued, the mice were still cancer-free.

Fooling cancer cells

“For the treatment to be effective, we have to trick the cancer cells to take up the nanoparticles so that the chemotherapy reaches its target,” Snipstad says.

To study this process, she has grown cancer cells and examined them under a microscope. Here, she has seen that the nanoparticles camouflage the chemotherapy drug, allowing the cancer cells to take them up. But for the treatment to work, the nanoparticles have to release the cancer drug exactly when and where it is needed.

“We can do that by changing the chemical composition of the nanoparticles so that we can tailor properties, including determining how quickly the nanoparticles break down. After the cell takes up the nanoparticle, the nanoparticle dissolves and releases the cancer drug inside the cell. That causes the cancer cell to stop dividing, and it will eventually shrink and die.

Close interdisciplinary cooperation

NTNU physics professor Catharina Davies heads the research group of which Snipstad is part. The group mainly works with nanoparticles.

The NTNU group works closely with SINTEF and St. Olavs Hospital in Trondheim. NTNU conducts the animal tests and studies the cancer cells. SINTEF has developed the bubbles containing nanoparticles, which provides the research platform. The cancer clinic and ultrasound group at St. Olavs contribute with their clinical skills.

“One of the things that I like about this project is that so many good people with different backgrounds are involved. Trondheim has a very good interdisciplinary environment, and this project needs all of these different disciplines for us to make progress,” Snipstad said.

No human trials anytime soon

While research results are very promising, it will still be some time before the method can be used in humans.

“It can take from 10-20 years from the time a discovery is made in the lab until it can be used as a treatment,” Snipstad said. “We’ve been working on this about six years, so we still have a lot to learn. 
We need to understand more about the mechanisms behind our success and we have to do much more work using microscopes to understand what is happening inside the tissues.”

Snipstad said that the find also has researchers excited to test the method on other types of cancers, because each type of cancer is different.

Possible treatment for brain cancer

This combination of bubbles, nanoparticles and ultrasound also opens the door on the possibility of treating brain diseases. The brain is protected by a special blood-brain barrier, which makes it difficult to deliver drugs to the brain for treatment. This barrier allows only substances that the brain needs to pass through the barrier, which means that for many brain diseases, there is no treatment whatsoever.

“But there is hope. By using ultrasound and our bubbles we have managed to deliver nanoparticles and drugs to the brain. This may be promising for the treatment of cancer and other diseases in the brain,” Snipstad said.

Source: Norwegian University of Science and Technology

Thanks 

“Stretch-ee” Gold Nanoclusters for Wearable Electronics

Researchers have fabricated highly deformable and stretchable conductors utilizing a Coil Flash Thermal Evaporation (CFTE) of gold nanoclusters that form robust thin metallic layers and maintain conductivity up to 200% on PDMS and 150% on textured rubber.

The CFTE method is known to produce gold nanoclusters with low ionization and kinetic energies, which minimizes carbonization of elastomers during deposition.

As the researchers report in ACS Applied Materials & Interfaces (“Facile Fabrication of Ultra-Stretchable Metallic Nanocluster Films for Wearable Electronics”), high metal-elastomer adhesion is obtained with textured substrates.

(a) Schematics showing the formation of low energy gold nanoclusters incident on stretchable elastomers. (b) TEM image of the deposited nanoclusters during the early stages of cluster coalescence. The green arrows show some of the deposited nanoclusters having a grainy morphology on a background of coalesced clusters. Scale bar-20 nm (c) The size distribution of the metal nanoclusters is shown along with a Normal fit (average cluster size ∼3.7 nm). (d) Shows the setup with eutectic liquid alloy contacts used for measurements. The discontinuity regions and the method to map them is shown. (e) Shows the change in resistance R(x) along the sample length for 25% and 70% strained samples emphasizing the discontinuity effect. Axes: (25% Bottom-Left and 70% Top-Right). (© 

The CFTE-gold films on textured substrates are highly robust and perform significantly better than e-beam, sputtered and implanted electrodes and exhibit only a small increase in resistance with strain (25 Ω-sq-1 at 100% strain).

The films stretch and relax in a bellow type open-and-close mechanism which allow for a robust performance with cyclic straining.

The CFTE is a one-step low vacuum process (0.5 × 10-2 millibar), not requiring intensive fabrication setups and large processing durations associated with other vapor deposition based processes.

The authors point out that the facile nature of this process opens up possibilities for easy incorporation of these electrodes for various functionalities involving deformable electronics like textile electronics, biointerfacing of devices, lab-on-chip devices, robotics, and stretchable metallic interconnects.

“Low cost and high throughput should make it possible to easily facilitate the integration of this process into numerous industrial production lines and clean room fabrication setups for ubiquitous electronics,” they conclude their report.

By Michael Berger – Michael is author of two books by the Royal Society of Chemistry: Nano-Society: Pushing the Boundaries of Technology and Nanotechnology: The Future is Tiny.

The Design of Future Nano-Electronic Circuits – Free Flowing Electrons in Graphene

Electrons flowing like liquid in graphene start a new wave of physics – University of Manchester 

A new understanding of the physics of conductive materials has been uncovered by scientists observing the unusual movement of electrons in graphene.

Graphene is many times more conductive than copper thanks, in part, to its two-dimensional structure. In most metals, conductivity is limited by crystal imperfections which cause electrons to frequently scatter like billiard balls when they move through the material.

Now, observations in experiments at the National Graphene Institute have provided essential understanding as to the peculiar behaviour of electron flows in graphene, which need to be considered in the design of future nanoelectronic circuits.

In some high-quality materials, like graphene, electrons can travel micron distances without scattering, improving the conductivity by orders of magnitude. This so-called ballistic regime, imposes the maximum possible conductance for any normal metal, which is defined by the Landauer-Buttiker formalism.

Appearing today in Nature Physics (“Superballistic flow of viscous electron fluid through graphene constrictions”), researchers at The University of Manchester, in collaboration with theoretical physicists led by Professor Marco Polini and Professor Leonid Levitov, show that Landauer’s fundamental limit can be breached in graphene. Even more fascinating is the mechanism responsible for this.

Last year, a new field in solid-state physics termed ‘electron hydrodynamics’ generated huge scientific interest. Three different experiments, including one performed by The University of Manchester, demonstrated that at certain temperatures, electrons collide with each other so frequently they start to flow collectively like a viscous fluid.

The new research demonstrates that this viscous fluid is even more conductive than ballistic electrons. 

The result is rather counter-intuitive, since typically scattering events act to lower the conductivity of a material, because they inhibit movement within the crystal. However, when electrons collide with each other, they start working together and ease current flow.

This happens because some electrons remain near the crystal edges, where momentum dissipation is highest, and move rather slowly. At the same time, they protect neighbouring electrons from colliding with those regions. Consequently, some electrons become super-ballistic as they are guided through the channel by their friends.

Sir Andre Geim said: “We know from school that additional disorder always creates extra electrical resistance. In our case, disorder induced by electron scattering actually reduces rather than increase resistance. This is unique and quite counterintuitive: Electrons when make up a liquid start propagating faster than if they were free, like in vacuum”.

The researchers measured the resistance of graphene constrictions, and found it decreases upon increasing temperature, in contrast to the usual metallic behaviour expected for doped graphene.

By studying how the resistance across the constrictions changes with temperature, the scientists revealed a new physical quantity which they called the viscous conductance. The measurements allowed them to determine electron viscosity to such a high precision that the extracted values showed remarkable quantitative agreement with theory.

Source: University of Manchester

Army COE Creates New Energy Efficient ‘Graphene Oxide’ Water Filter at Commercial Scale

The Army Corps of Engineers have successfully created a usable prototype of a new type of water filter.

The membranes are made of a mixture of chitosan, a material commonly found in shrimp shells, and a new synthetic chemical known as “graphene oxide”. Graphene oxide is a highly researched chemical worldwide.

  According to the Army Corps, one problem encountered by scientists working with graphene oxide is not being able to synthesize the material on a scale that can be put to use.

“One of the major breakthroughs that we’ve had here is that with our casting process, we’re not limited by size,” explains Luke Gurtowski, a research chemical engineer working on the membranes.

These filters have been found to effectively remove a number of different contaminants commonly found in water.

Dr. Christopher Griggs is the research scientist in charge of overseeing development of the new membranes.

Dr. Griggs told us, “Anybody who’s experienced water shortages or has been concerned about their water quality, or any type of contaminants in the water, this type of technology certainly works to address that.”

Another challenged faced by conventional water filtering methods is maintaining high energy efficiency.

“It requires a lot of energy for the net driving pressure to force the water through the membrane,” Dr. Griggs explains. “…we’re going to have to look to new materials to try to get those efficiency gains, and so graphene oxide is a very promising candidate for that.”

The Engineer Research and Development Center currently has two patents associated with the new filters and hopes to apply them for both civil and military purposes in the near future. 

Super Capacitors Could Make the Tesla ‘Battery Model for an EV World’ Obsolete: Videos

Tesla’s growth has been built on its pioneering battery technology but they’re slow to charge, have limited lifetimes and are heavy. The latest research on supercapacitors does away with all of that and may mean ‘Tesla Battery Model for an EV World’ is a losing bet (Watch Videos Below)

Introduction

Transportation is the largest consumer of oil and the globally, it’s the biggest source of pollution, greenhouse gases, soot and fine particulates; gasoline and diesel have fuelled global transport and been the lifeblood of the international oil majors and national oil companies.

That, however, may be changing. Oil’s power density and affordable price has made alternatives non-starters, pushed many mass transit systems to bankruptcy, and made auto, tyre, road construction, and insurance companies rich.

Fuel energy density including supercapacitors

The Tesla effect

Then came Tesla, for the first time offering a slick, high-performance car with reasonable range.

Currently too expensive for the mass market, Tesla has nevertheless challenged the internal combustion engine (ICE) industry and forced virtually all car markers to get into electric vehicles.

With a $5 billion gigafactory just completed in July 2016 near Reno, Nevada. Tesla is promising to move mainstream, offering more affordable cars with decent range. 

That is all wonderful. But Tesla and all other electric and hybrid cars still suffer from lack of charging infrastructure, and even when that is in place, drivers will have to take long breaks on long drives to recharge their batteries. 
Depending on the details, 90 minutes or more are typically needed to more-or-less recharge an empty car battery, an annoying wait compared to a five-minute fillup at the corner gas station.

 

Tesla’s growth has been built on its pioneering battery technology but they’re slow to charge, have limited lifetimes and are heavy. The latest research on supercapacitors does away with all of that and may mean ‘Tesla Battery Model for an EV World’ is a losing bet

Battery Woes

Moreover, even with Tesla’s slick design, the batteries are heavy and can only be charged/discharged so many times, after which their performance drops. Trucks and heavy-duty vehicles pose even more difficult challenges if they are not recharged frequently – not always convenient or practical. Batteries, in other words, are not a perfect substitute for cheap petrol which is available nearly everywhere you go.

What would be ideal is a light, inexpensive battery that can pack large amounts of energy in a small space, can be charged more or less instantly, and discharged more or less indefinitely without loss of performance. 

That would be the holy grail of storage, not only challenging the ICEs but also making Tesla’s gigafactory virtually obsolete before it starts mass production.

Super Potential for Supercapacitors

A new generation of supercapacitors made from cheap and plentiful material – now in laboratories – is expected to become commercial in three to five years. According to UCLA Professor Richard Kaner, the company he is affiliated with, Nanotech Energy, is using graphene as the basic medium for storing energy. (Also See Video for ‘Tenka Energy’ below)

As the technology moves out of the laboratory, he expects it to initially find a role in high-value applications such as mobile phones and computers, followed by other applications such as electric vehicles.

Supercapacitors Recharge Rate

The ability to fast-charge a supercapacitor in, say, two minutes or so, will solve the range anxiety associated with current EVs. 
Imagine pulling into an electric charging station and getting more or less fully recharged in the amount of time it takes to fill up your tank with gas. Who needs clunky, noisy, polluting cars, or even Tesla batteries?

The same fast-charging supercapacitors can power mass transit buses in cities around the world. If the bus’ supercapacitor can be charged in two minutes or less, then every bus stop can be a charging station, allowing the bus to travel long distances without ever running out of juice. That would be a game changer.

Tesla, which is facing many daunting deadlines and competition from multiple directions, may find that its gigafactory is a losing bet if supercapacitors come to deliver as their proponents claim.

Now THAT … That would be yet another game changer!

From ‘The Energy Analyst’

 

Watch: Video Presentation of New ‘Tenka Power Max SuperCap’

Printed Organic Photovoltaics: OPVIUS

By developing self-adhesive OPV-films, OPVIUS together with S+L Selbstklebeprodukte GmbH are broadening the horizons for OPV products and OPV integration.
Imbedding OPVIUS modules in transparent carrier materials, for example glass or foil membranes, has been possible for some time.
Their integration into laminated polycarbonate sheets was recently presented as part of an installation at the Climate-Pavilion at the State Horticultural Show in Thüringen.

The integration techniques developed up until now are mainly aimed at integration, that is to say embedding the module in the carrier material by way of a lamination procedure. This is generally limited to transparent materials and predominantly serves the market for original equipment manufacturers.
OPVs can be integrated directly into construction materials whilst they are manufactured, and are therefore installed together with these materials.

By developing self-adhesive OPVIUS products, an additional solution can now be provided that will be of interest when retrofitting existing surfaces, as well as for use on non-transparent carrier materials.
S+L Selbstklebeprodukte GmbH’s many years of experience working with stickers for public transport as well as the manufacturing of classic car decals is of central interest to OPVIUS GmbH.

Their expertise in various applications, processing procedures, and working with new technologies in the field of foils, all build the foundations of a joint collaboration.
Combined with OPVIUS’ production technology and the resulting freedom in terms of colour and form, this expertise will enable users to obtain customised products that are easy to install. This will significantly expand the range of applications of printed organic photovoltaics.
“By developing self-adhesive OPV foils, we can bring our products further into the market, and make them available to an additional user-group. OPVIUS stickers provide many new solutions, particularly for already existing surfaces” says Hermann Issa, Senior Director, Business Development and Sales, OPVIUS.
“The need for high quality in order to ensure a good and lasting adhesive bond is frequently underestimated. In this regard, in terms of cooperation, S+L Selbstklebeprodukte GmbH was our first choice for implementation.
It has paid off.”   Christian Lins, Business Director of S+L Selbstklebeprodukte GmbH added: “A good adhesion needs to work both visually and flawlessly in terms of function, and needs to last in both indoor and outdoor settings.

In addition, we had to look at the properties of the OPVs, and adjust our stickers to the OPVIUS products. Here, our great wealth of experience of adhesion to a large range of substrates, for example trains and buses, paid off, as they also need to be long-lasting and visually perfect under conditions of constant exposure.”
Source and top image: OPVIUS Learn more at the next leading event on the topic:

Energy Independent Electric Vehicles 2017 on 27 – 28 Sep 2017 in TU Delft, Delft, Netherlands hosted by IDTechEx.

 

Read more at:

http://www.electricvehiclesresearch.com/articles/11478/printed-organic-photovoltaics

Flexible Batteries Power the Future of Wearable Technology: U of Manchester

Credit: University of Manchester

The rapid development of wearable technology has received another boost from a new development using graphene for printed electronic devices.

New research from The University of Manchester has demonstrated flexible battery-like devices printed directly on to textiles using a simple screen-printing technique.

The current hurdle with wearable technology is how to power devices without the need for cumbersome battery packs. Devices known as supercapacitors are one way to achieve this. A supercapacitor acts similarly to a battery but allows for rapid charging which can fully charge devices in seconds.

Now a solid-state flexible supercapacitor device has been demonstrated by using conductive graphene-oxide ink to print onto cotton fabric. As reported in the journal 2-D Materials the printed electrodes exhibited excellent mechanical stability due to the strong interaction between the ink and textile substrate. 

Further development of graphene-oxide printed supercapacitors could turn the vast potential of wearable technology into the norm. High-performance sportswear that monitors performance, embedded health-monitoring devices, lightweight military gear, new classes of mobile communication devices and even wearable computers are just some of the applications that could become available following further research and development.

To power these new wearable devices, the energy storage system must have reasonable mechanical flexibility in addition to high energy and power density, good operational safety, long cycling life and be low cost.

 Credit: University of Manchester

Dr Nazmul Karim, Knowledge Exchange Fellow, the National Graphene Institute and co-author of the paper said: “The development of graphene-based flexible textile supercapacitor using a simple and scalable printing technique is a significant step towards realising multifunctional next generation wearable e-textiles.”

“It will open up possibilities of making an environmental friendly and cost-effective smart e-textile that can store energy and monitor human activity and physiological condition at the same time”.

Graphene-oxide is a form of graphene which can be produced relatively cheaply in an ink-like solution. This solution can be applied to textiles to create supercapacitors which become part of the fabric itself.

Dr Amor Abdelkader, also co-author of the paper said: “Textiles are some of the most flexible substrates, and for the first time, we printed a stable device that can store energy and be as flexible as cotton.

“The device is also washable, which makes it practically possible to use it for the future smart clothes. We believe this work will open the door for printing other types of devices on textile using 2-D-materials inks.”

The University of Manchester is currently completing the construction of its second major graphene facility to complement the National Graphene Institute (NGI). Set to be completed 2018, the £60m Graphene Engineering Innovation Centre (GEIC) will be an international research and technology facility.

The GEIC will offer the UK the unique opportunity to establish a leading role in graphene and related two-dimensional materials. The GEIC will be primarily industry-led and focus on pilot production and characterisation.

 Explore further: Researchers develop simple way to fabricate micro-supercapacitors with high energy density

Provided by: University of Manchester