Image: REUTERS/Nick Carey
Graphene is a modern marvel. It is comprised of a single, two-dimensional layer of carbon, yet is 200 times stronger than steel and more conductive than any other material, according to the University of Manchester, where it was first isolated in 2004.
Graphene also has multiple potential uses, including in biomedical applications such as targeted drug delivery, and for improving the lifespan of smartphone batteries.
Now, a team of researchers at the University of Arkansas has found evidence to suggest graphene could also be used to provide an unlimited supply of clean energy.
The team says its research is based on graphene’s ability to “ripple” into the third dimension, similar to waves moving across the surface of the ocean. This motion, the researchers say, can be harvested into energy.
To study the movement of graphene, lead researcher Paul Thibado and his team laid sheets of the material across a copper grid that acted as a scaffold, which allowed the graphene to move freely.
Thibado says graphene could power biomedical devices such as pacemakers.
Image: Russell Cothren
The researchers used a scanning tunnelling microscope (STM) to observe the movements, finding that narrowing the focus to study individual ripples drew clearer results.
In analysing the data, Thibado observed both small, random fluctuations, known as Brownian motion, and larger, coordinated movements.
A scanning tunnelling microscope.
Image: University of Arkansas
As the atoms on a sheet of graphene vibrate in response to the ambient temperature, these movements invert their curvature, which creates energy, the researchers say.
“This is the key to using the motion of 2D materials as a source of harvestable energy,” Thibado says.
“Unlike atoms in a liquid, which move in random directions, atoms connected in a sheet of graphene move together. This means their energy can be collected using existing nanotechnology.”
The pieces of graphene in Thibado’s laboratory measure about 10 microns across (more than 20,000 could fit on the head of a pin). Each fluctuation exhibited by an individual ripple measures only 10 nanometres by 10 nanometres, and could produce 10 picowatts of power, the researchers say.
As a result, each micro-sized membrane has the potential to produce enough energy to power a wristwatch, and would never wear out or need charging.
Sheet of graphene as seen through Thibado’s STM
Image: University of Arkansas
Thibado has created a device, called the Vibration Energy Harvester, that he claims is capable of turning this harvested energy into electricity, as the below video illustrates.
This self-charging power source also has the potential to convert everyday objects into smart devices, as well as powering more sophisticated biomedical devices such as pacemakers, hearing aids and wearable sensors.
Thibado says: “Self-powering enables smart bio-implants, which would profoundly impact society.”
Have you read?
21 Feb 2018
University of Texas at Austin. This is the world’s thinnest wearable Health Monitor, designed and developed by the researchers at the University of Texas at Austin, in the form of a “Graphene-Ink Tattoo”.
Most health monitors in use today are bulky and tend to restrict patients movements. This graphene tattoo will eliminate these restrictions. It picks up electric signal given off by the body and transmits it to a smartphone app.
Rice University scientists who introduced laser-induced graphene (LIG) have enhanced their technique to produce what may become a new class of edible electronics.
The Rice lab of chemist James Tour, which once turned Girl Scout cookies into graphene, is investigating ways to write graphene patterns onto food and other materials to quickly embed conductive identification tags and sensors into the products themselves.
“This is not ink,” Tour said. “This is taking the material itself and converting it into graphene.” Read More: Rice University Expands LIG (laser induced graphene) Research
Automated, unmanned drones are poised to revolutionize the package delivery industry, with a number of companies already testing drone-based delivery methods.
A new study in Nature Communications looks at the climate impact of a shift from truck-based to drone-based package delivery. It finds that while small drones carrying packages weighing less than 0.5 kg would reduce greenhouse gas emissions compared to diesel or electric trucks anywhere in the U.S., the same is not true for larger drones carrying heavier packages.
Watch Our New Tenka Energy Video:
Tenka Energy, Inc. Building Ultra-Thin Energy Dense SuperCaps and NexGen Nano-Enabled Pouch & Cylindrical Batteries – Energy Storage Made Small and POWERFUL! YouTube Video
Despite being a promising electrode material, bulk cobalt oxide (Co3O4) exhibits poor lithium ion storage properties. Nanostructuring, e.g. making Co3O4 into ultrathin nanosheets, shows improved performance, however, Co3O4-based nanomaterials still lack long-term stability and high rate capability due to sluggish ion transport and structure degradation. Read More …
MIT: Device makes power conversion more efficient New design could dramatically cut energy waste in electric vehicles, data centers, and the power grid
Power electronics, which do things like modify voltages or convert between direct and alternating current, are everywhere. They’re in the power bricks we use to charge our portable devices; they’re in the battery packs of electric cars; and they’re in the power grid itself, where they mediate between high-voltage transmission lines and the lower voltages of household electrical sockets. Read More …
Elon Musk and Tesla have made some bold claims for the new Tesla Semi and Roadster. Those who understand batteries have been scratching their heads trying to figure out how the company can deliver the specs it’s promising – and concluding that the only possible way is some as-yet-unannounced advancement in battery technology. Read More …
Watch Our Video on New Energy Storage Technology: Supercapacitors and Batteries
18 May 2017
Battery stores energy in nontoxic, noncorrosive aqueous solutions
Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new flow battery that stores energy in organic molecules dissolved in neutral pH water.
This new chemistry allows for a non-toxic, non-corrosive battery with an exceptionally long lifetime and offers the potential to significantly decrease the costs of production.
The research, published in ACS Energy Letters, was led by Michael Aziz, the Gene and Tracy Sykes Professor of Materials and Energy Technologies and Roy Gordon, the Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science.
Flow batteries store energy in liquid solutions in external tanks — the bigger the tanks, the more energy they store.
A new company Tenka Energy, LLC ™ has been formed to exploit and commercialize the Next Generation Super-Capacitors and Batteries. The opportunity is based on Nanoporous-Nickel Flexible Thin-Form, Scalable Super Capacitors and Si-Nanowire Battery Technologies with Exclusive IP Licensing Rights from Rice University.
… Problem 1: Current capacitors and batteries being supplied to the relevant markets lack the sustainable power density, discharge and recharge cycle and warranty life. Combined with a weight/ size challenge and the lack of a ‘flexible form factor’, existing solutions lack the ability to scale and manufacture at Low Cost, to satisfy the identified industries’ need for solutions that provide commercial viability & performance.
Solution: For Marine & Drone Batteries – Medical Devices
- High Energy Density = 2X More Time on the Water; 2X Flight Time for Drones
- Simplified Manufacturing = Lower Costs
- Simple Electrode Architecture = Flex Form Factor (10X Energy Density Factor)
- Flexible Form = Dramatically Less Weight and Better Weight Distribution
- Easy to Scale Technology
To Read the Full Article Click on the Link Below:
28 Feb 2017
Technology I: University of Central Florida
Leaving your phone plugged in for hours could become a thing of the past, thanks to a new type of battery technology that charges in seconds and lasts for over a week.
Watch the Video
While it probably won’t be commercially available for a years, the researchers said it has the potential to be used in phones, wearables and electric vehicles.
“If they were to replace the batteries with these supercapacitors, you could charge your mobile phone in a few seconds and you wouldn’t need to charge it again for over a week,” said Nitin Choudhary, a UCF postdoctoral associate, who conducted much of the research, published in the academic journal ACS Nano.
How does it work?
Unlike conventional batteries, supercapacitors store electricity statically on their surface which means they can charge and deliver energy rapidly. But supercapacitors have a major shortcoming: they need large surface areas in order to hold lots of energy.
To overcome the problem, the researchers developed supercapacitors built with millions of nano-wires and shells made from two-dimensional materials only a few atoms thick, which allows for super-fast charging. Their prototype is only about the size of a fingernail.
“For small electronic devices, our materials are surpassing the conventional ones worldwide in terms of energy density, power density and cyclic stability,” Choudhary said.
Cyclic stability refers to how many times a battery can be charged, drained and recharged before it starts to degrade. For lithium-ion batteries, this is typically fewer than 1,500 times.
Supercapacitors with two-dimensional materials can be recharged a few thousand times. But the researchers say their prototype still works like new even after being recharged 30,000 times.
Those that use the new materials could be used in phones, tablets and other electronic devices, as well as electric vehicles. And because they’re flexible, it could mean a significant development for wearables.
Technology II: Rice University
Identified Key Markets and Commercial Applications
- Medical Devices and Wearable Electronics
- Drone/Marine Batteries and Power Banks
- Powered Smart Cards and Motor Cycle/ EV Batteries
- Sensors & Power Units for the iOT (Internet of Things) [Flexible Form, Energy Dense]
The Coming Power Needs of the iOT
- The IoT is populated with billions of tiny devices.
- They’re smart.
- They’re cheap.
- They’re mobile.
- They need to communicate.
- Their numbers growing at 20%-30%/Year.
The iOT is Hungry for POWER! All this demands supercapacitors that can pack a lot of affordable power in very small volumes …Ten times more than today’s best supercapacitors can provide.
Highly Scalable – Energy Dense – Flexible Form – Rapid Charge
Problem 1: Current capacitors and batteries being supplied to the relevant markets lack the sustainable power density, discharge and recharge cycle, warranty life combined with a ‘flexible form factor’ to scale and satisfy the identified industry need for commercial viability & performance.
Solution I: (Minimal Value Product) Tenka is currently providing full, functional Super Capacitor prototypes to an initial customer in the Digital Powered Smart Card industry and has received two (2) phased Contingent Purchase Orders during the First Year Operating Cycle for 120,000 Units and 1,200,000 Units respectively.
Solution II: For Drone/ Marine Batteries – Power Banks & Medical Devices
- Double the current ‘Time Aloft’ (1 hour+)
- Reduces operating costs
- Marine batteries – Less weight, longer life, flex form
- Provides Fast Recharging, Extended Life Warranty.
- Full -battery prototypes being developed
Small batteries will be produced first for Powered Digital Smart Cards (In addition to the MVP Super Caps) solving packaging before scaling up drone battery operations. Technical risks are mainly associated with packaging and scaling.
The Operational Plan is to take full advantage of the gained ‘know how’ (Trade Secrets and Processes) of scaling and packaging solutions developed for the Powered Digital Smart Card and the iOT, to facilitate the roll-out of these additional Application Opportunities. Leveraging gained knowledge from operations is projected to significantly increase margins and profitability. We will begin where the Economies of Scale and Entry Point make sense (cents)!
“We are building and Energy Storage Company starting Small & Growing Big!”
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Fuel cell electric vehicles have a long way to go before they can compete with their battery EV cousins, and energy storage is a key sticking point when the fuel is hydrogen. Hydrogen is light, plentiful, and fabulously energy dense, but energy storage in a personal mobility unit racing down a crowded highway is a different kind of chicken. Safety, cost, and performance are critical sticking points, and a research team at Lawrence Berkeley Laboratory is on to a solution for at least one of those.
Energy Storage Challenges For Hydrogen Fuel Cell EVs
The US Energy Department’s 2015 annual report provides a birds-eye view of the array of energy storage solutions that are emerging for hydrogen fuel cells, including advancements in hydrogen tank technology as well as solids-based storage.
Despite the progress, according to the Energy Department, challenges still remain for stationary and portable fuel cells in terms of raising the energy storage density, and there are “significant challenges” for fuel cell EVs. The problem is this:
Hydrogen has the highest energy per mass of any fuel; however, its low ambient temperature density results in a low energy per unit volume, therefore requiring the development of advanced storage methods that have potential for higher energy density.
The Energy Department has set a goal of 2020 for achieving verifiable hydrogen storage systems for light duty fuel cell EVs that meet the driving public’s thirst for range, comfort, refueling convenience, and performance. Here are the targets:
1.8 kWh/kg system (5.5 wt.% hydrogen)
1.3 kWh/L system (0.040 kg hydrogen/L)
$10/kWh ($333/kg stored hydrogen capacity)
However, the Energy Department is already looking beyond the current state of on-road technology to meet its 2020 goal. According to the agency, the 300-mile range is being met by using compressed gas, high pressure energy storage technology, and the problem is that competing technology on the market today — primarily gasmobiles and hybrids — already exceeds that range.
To compete for consumers on the open market, the agency is pursuing a near-term goal of improving compressed gas storage, primarily by deploying fiber reinforced composites that enable 700 bar pressure.
The long term goal consists of two pathways. One is to improve “cold” compressed gas energy storage technology, and the other is to go a different route altogether and store hydrogen within materials such as sorbents, chemical hydrogen storage materials, and metal hydrides.
The Berkeley Lab Energy Storage Solution
Where were we? Oh right, Berkeley Lab. Berkeley Lab has been tackling the metal hydride pathway.
Metal hydrides are compounds that consist of a transition metal bonded to hydrogen. They are believed to be the most “technologically relevant” class of materials for storing hydrogen, partly due to the broad range of applications.
That’s the theory. The problem is that when it comes to real world performance, metal hydrides are highly sensitive to contamination and they degrade somewhat rapidly unless properly shielded.
The Berkeley Lab energy storage solution consists of a graphene “filter” encasing nanocrystals of magnesium. With the addition of the graphene layer, the magnesium crystals act as a sort of sponge for absorbing hydrogen, providing both safety and compactness without causing performance issues:
The graphene shields the nanocrystals from oxygen and moisture and contaminants, while tiny, natural holes allow the smaller hydrogen molecules to pass through. This filtering process overcomes common problems degrading the performance of metal hydrides for hydrogen storage.
Berkeley Lab has provided this photo to show off how stable the crystals are when exposed to air (for scale, the bottle cap is about the size of a thumbnail):
At one atom thick (yes, one atom), graphene is known to be an incredibly finicky material to work with. It is extremely difficult to synthesize it without defects, but that’s not a problem for this energy storage solution. The defects are actually desirable in this case. The tiny gaps enable molecules of hydrogen gas to wriggle through, but oxygen, water, and other contaminants are too large to penetrate the shield.
The new energy formula also solves another key challenge for metal hydrides. They tend to take in and dispense hydrogen at a relatively slow pace, but the Berkeley Lab solution has sped up the intake-outflow cycle significantly. That effect is attributed to the nanoscale size of the graphene-shielded crystals, which provide a greater surface area.
Energy Department Gets The Last Word?
We’ve been having a lively debate about fuel cell electric EVs over here at CleanTechnica, so let’s hear from the Berkeley Lab team:
A potential advantage for hydrogen-fuel-cell vehicles, in addition to their reduced environmental impact over standard-fuel vehicles, is the high specific energy of hydrogen, which means that hydrogen fuel cells can potentially take up less weight than other battery systems and fuel sources while yielding more electrical energy.
However, the team also makes it clear that:
More R&D is needed to realize higher-capacity hydrogen storage for long-range vehicle applications that exceed the performance of existing electric-vehicle batteries…
Among other issues, the next step for a sustainable fuel cell EV future is to develop sustainable and renewable sources for hydrogen fuel. Currently the main source of hydrogen is natural gas, which puts fuel cell EVs in the same boat as battery EVs that draw electricity from a coal or natural gas-fired grid.
California is committed to 33 percent energy from renewable resources by 2020. With that deadline fast approaching, researchers across the state are busy exploring options.
Solar energy is attractive but for widespread adoption, it requires transformation into a storable form. This week in ACS Central Science, researchers report that nanowires made from multiple metal oxides could put solar ahead in this race.
One way to harness solar power for broader use is through photoelectrochemical (PEC) water splitting that provides hydrogen for fuel cells. Many materials that can perform the reaction exist, but most of these candidates suffer from issues, ranging from efficiency to stability and cost.
Peidong Yang and colleagues designed a system where nanowires from one of the most commonly used materials (TiO2) acts as a “host” for “guest” nanoparticles from another oxide called BiVO4. BiVO4 is a newly introduced material that is among the best ones for absorbing light and performing the water splitting reaction, but does not carry charge well while TiO2 is stable, cheap and an efficient charge carrier but does not absorb light well.
Together with a unique studded nanowire architecture, the new system works better than either material alone.
The authors state their approach can be used to improve the efficiencies of other photoconversion materials.
We report the use of Ta:TiO2|BiVO4 as a photoanode for use in solar water splitting cells. This host−guest system makes use of the favorable band alignment between the two semiconductors. The nanowire architecture allows for simultaneously high light absorption and carrier collection for efficient solar water oxidation.
Metal oxides that absorb visible light are attractive for use as photoanodes in photoelectrosynthetic cells. However, their performance is often limited by poor charge carrier transport. We show that this problem can be addressed by using separate materials for light absorption and carrier transport. Here, we report a Ta:TiO2|BiVO4 nanowire photoanode, in which BiVO4 acts as a visible light-absorber and Ta:TiO2 acts as a high surface area electron conductor. Electrochemical and spectroscopic measurements provide experimental evidence for the type II band alignment necessary for favorable electron transfer from BiVO4 to TiO2. The host–guest nanowire architecture presented here allows for simultaneously high light absorption and carrier collection efficiency, with an onset of anodic photocurrent near 0.2 V vs RHE, and a photocurrent density of 2.1 mA/cm2 at 1.23 V vs RHE.
Article adapted from a American Chemical Society news release. To Read the FULL release, please click on the link provided below.
Publication: TiO2/BiVO4 Nanowire Heterostructure Photoanodes Based on Type II Band Alignment. Resasco, J et al. ACS Central Science (3 February, 2016): Click here to view.
Genesis Nanotechnology – “Great Things from Small Things”
21 Oct 2015
The opportunity is electricity storage, which until now has been limited by technology to a relatively modest scale. That’s about to change. And it means that Canada – and specifically Ontario – can become an ideal seedbed for storage technology, because there are ready markets for both large- and small-scale storage systems.
First, the large scale. Ontario has a fleet of nuclear generators that operate around the clock, and come close to filling the demand for power at off-peak hours. In addition, Ontario has developed a large renewable energy sector of wind and solar generation (in addition to its traditional hydro stations.) Problems sometimes arise when the natural weather cycles that drive wind and solar production are out of synch with the market cycle. On a sunny, breezy Saturday afternoon in May, with the nuclear plants running flat out, the hydro stations churning out power with the spring runoff and solar and wind systems near peak production, Ontario may have more electricity than it needs.
Our electricity system operators have a solution, of course: Sell the excess electricity to our neighbours. But since our neighbours are often in the same boat, Ontario must cut the price close to zero – or in extreme situations, even pay neighbouring states or provinces to absorb our overproduction.
Wouldn’t it make far more sense to store that excess energy, knowing that it will be needed in a matter of days, or even hours? What’s been lacking is the technology to do the job.
That’s changing however, as Ontario’s current program to procure 50 megawatts of storage capacity demonstrates. Companies with a variety of approaches are working hard to bring their solutions to market – many of them clustered at the MaRS centre in Toronto. Some, such as Hydrogenics Corp., convert electricity into hydrogen, which can be used to supplement natural gas.
My own company, NRStor, has partnered with Temporal Power and is operating a flywheel storage system in Minto, Ont., that helps the market operator to maintain consistent voltage on the grid.
Of course, businesses around the globe are looking at the same opportunities as we are, and here lies the opportunity for Canada to rebrand its energy economy.
A recent report by Deutsche Bank calls battery storage the “holy grail of solar penetration,” and believes that with the current rate of progress in improving efficiency, mass adoption of lithium ion batteries at a commercial/utility scale could occur before 2020.
Analysis by Prof. Andrew Ford of Washington State University calculates that a 1,000-megawatt air storage system from U.S.-based General Compression Inc. could deliver $6- to $8-billion of value to Ontario – in the form of lower energy costs to local utilities – over a 20-year period. All this is of interest to large-scale electricity system operators, big utilities and their customers.
But there is another reason for us to pay attention to energy storage – a reason grounded on a much more human scale. There are still large rural areas around the globe where there is no reliable electrical grid – including Northern Canada.
There is great potential for these communities, including remote First Nations communities, to improve their standard of living by installing microscale renewable generation in combination with storage, and relying less on carbon-spewing diesel generators, powered by fuel that must be transported long distances at great expense.
Storage is the key to making renewable energy a fully competitive component of any electrical grid. It can make our grid cleaner and more efficient, for the benefit of all consumers – large and small, urban and rural. We have the chance, in Canada, to become world leaders in developing this technology. Let’s seize it.
Annette Verschuren is the chairwoman and CEO of NRStor and on the board of MaRS Discovery District.
Annette Verschuren is speaking at the Cleantech Canadian Innovation Exchange (CIX Cleantech) conference in Toronto on Oct. 15.