22 Apr 2017
It’s time for an update on graphene, that super material of the future! Scientists have come up with some new ways of making it that are easier and cheaper than ever before.
“Fascination with this material stems from its remarkable physical properties and the potential applications these properties offer for the future. Although scientists knew one atom thick, two-dimensional crystal graphene existed, no-one had worked out how to extract it from graphite.”
Charge Your Cell Phone In 5 Seconds
Supercapacitors: They’ll enable you to charge your cell phone in 5 seconds, or an electric car in about a minute. They’re cheap, biodegradable, never wear out and as Trace’ll tell you, could be powering your life sooner than you’d think.
Still More …
Scientists cook up material 200 times stronger than steel out of soybean oil
“Many production techniques involve the use of intense heat in a vacuum, and expensive ingredients like high-purity metals and explosive compressed gases. Now a team of Australian scientists has detailed how they turned cheap everyday ingredients into graphene under normal air conditions. They said the research, published today in the journal Nature Communications, may open up a new avenue for the low-cost synthesis of the highly sought-after material.” Click on the Link below to read more:
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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23 Feb 2016
Yat Li (left) and Tianyu Liu worked with researchers at Lawrence Livermore National Laboratory to develop supercapacitors using 3D-printed graphene aerogel electrodes. Credit: T. Stephens
Scientists at UC Santa Cruz and Lawrence Livermore National Laboratory (LLNL) have reported the first example of ultrafast 3D-printed graphene supercapacitor electrodes that outperform comparable electrodes made via traditional methods. Their results open the door to novel, unconstrained designs of highly efficient energy storage systems for smartphones, wearables, implantable devices, electric cars and wireless sensors.
Using a 3D-printing process called direct-ink writing and a graphene-oxide composite ink, the team was able to print micro-architected electrodes and build supercapacitors with excellent performance characteristics. The results were published online January 20 in the journal Nano Letters and will be featured on the cover of the March issue of the journal.
“Supercapacitor devices using our 3D-printed graphene electrodes with thicknesses on the order of millimeters exhibit outstanding capacitance retention and power densities,” said corresponding author Yat Li, associate professor of chemistry at UC Santa Cruz. “This performance greatly exceeds the performance of conventional devices with thick electrodes, and it equals or exceeds the performance of reported devices made with electrodes 10 to 100 times thinner.”
LLNL engineer Cheng Zhu and UCSC graduate student Tianyu Liu are lead authors of the paper. “This breaks through the limitations of what 2D manufacturing can do,” Zhu said. “We can fabricate a large range of 3D architectures. In a phone, for instance, you would only need to leave a small area for energy storage. The geometry can be very complex.”
Supercapacitors also can charge incredibly fast, Zhu said, in theory requiring just a few minutes or seconds to reach full capacity. In the future, the researchers believe newly designed 3D-printed supercapacitors will be used to create unique electronics that are currently difficult or even impossible to make using other synthetic methods, including fully customized smartphones and paper-based or foldable devices, while at the same time achieving unprecedented levels of performance.
According to Li, several key breakthroughs made these novel devices possible, starting with the development of a printable graphene-based ink. Modification of the 3D printing scheme to be compatible with aerogel processing made it possible to maintain the important mechanical and electrical properties of single graphene sheets in the 3D-printed structures. Finally, the use of 3D printing to intelligently engineer periodic macropores into the graphene electrode significantly enhances mass transport, allowing the device to support much faster charge/discharge rates without degrading its capacity.
“This work provides an example of how 3D-printed materials such as graphene aerogels can significantly expand the design space for fabricating high-performance and fully integrable energy storage devices optimized for a broad range of applications,” Li said.
The advantages of graphene-based inks include their ultrahigh surface area, lightweight properties, elasticity, and superior electrical conductivity. The graphene composite aerogel supercapacitors are also extremely stable, the researchers reported, capable of nearly fully retaining their energy capacity after 10,000 consecutive charging and discharging cycles.
“Graphene is a really incredible material because it is essentially a single atomic layer that can be created from graphite. Because of its structure and crystalline arrangement, it has really phenomenal capabilities,” said LLNL materials engineer Eric Duoss.
Over the next year, the researchers intend to expand the technology by developing new 3D designs, using different inks, and improving the performance of existing materials.
Explore further: Energy storage of the future
More information: Cheng Zhu et al. Supercapacitors Based on Three-Dimensional Hierarchical Graphene Aerogels with Periodic Macropores, Nano Letters (2016). DOI: 10.1021/acs.nanolett.5b04965
A team of researchers working in China has found a way to dramatically improve the energy storage capacity of supercapacitors—by doping carbon tubes with nitrogen. In their paper published in the journal Science, the team describes their process and how well the newly developed supercapacitors worked, and their goal of one day helping supercapacitors compete with batteries.
Like a battery, a capacitor is able to hold a charge, unlike a battery, however, it is able to be charged and discharged very quickly—the down side to capacitors is that they cannot hold nearly as much charge per kilogram as batteries. The work by the team in China is a step towards increasing the amount of charge that can be held by supercapacitors (capacitors that have much higher capacitance than standard capacitors—they generally employ carbon-based electrodes)—in this case, they report a threefold increase using their new method—noting also that that their supercapacitor was capable of storing 41 watt-hours per kilogram and could deliver 26 kilowatts per kilogram to a device.
The new supercapacitor was made by first forming a template made of tubes of silica. The team then covered the inside of the tubes with carbon using chemical vapor deposition and then etched away the silica, leaving just the carbon tubes, each approximately 4 to 6 nanometers in length. Then, the carbon tubes were doped with nitrogen atoms. Electrodes were made from the resulting material by pressing it in powder form into a graphene foam. The researchers report that the doping aided in chemical reactions within the supercapacitor without causing any changes to its electrical conductivity, which meant that it was still able to charge and discharge as quickly as conventional supercapcitors. The only difference was the dramatically increased storage capacity.
Because of the huge increase in storage capacity, the team believes they are on the path to building a supercapacitor able to compete directly with batteries, perhaps even lithium-ion batteries. They note that would mean being able to charge a phone in mere seconds. But before that can happen, the team is looking to industrialize their current new supercapacitor, to allow for its use in actual devices.
More information: T. Lin et al. Nitrogen-doped mesoporous carbon of extraordinary capacitance for electrochemical energy storage, Science (2015). DOI: 10.1126/science.aab3798
Carbon-based supercapacitors can provide high electrical power, but they do not have sufficient energy density to directly compete with batteries. We found that a nitrogen-doped ordered mesoporous few-layer carbon has a capacitance of 855 farads per gram in aqueous electrolytes and can be bipolarly charged or discharged at a fast, carbon-like speed. The improvement mostly stems from robust redox reactions at nitrogen-associated defects that transform inert graphene-like layered carbon into an electrochemically active substance without affecting its electric conductivity. These bipolar aqueous-electrolyte electrochemical cells offer power densities and lifetimes similar to those of carbon-based supercapacitors and can store a specific energy of 41 watt-hours per kilogram (19.5 watt-hours per liter).
29 Sep 2015
|Some of the 300 million tires discarded each year in the United States alone could be used in supercapacitors for vehicles and the electric grid using a technology developed at the Department of Energy’s Oak Ridge National Laboratory and Drexel University.|
|By employing proprietary pretreatment and processing, a team led by Parans Paranthaman has created flexible polymer carbon composite films as electrodes for supercapacitors. These devices are useful in applications for cars, buses and forklifts that require rapid charge and discharge cycles with high power and high energy density. Supercapacitors with this technology in electrodes saw just a 2 percent drop after 10,000 charge/discharge cycles.|
|Instead of ending up in landfills, old tires can supply a key ingredient for supercapacitors. (Image: ORNL)|
|The technology, described in a paper published in ChemSusChem(“Waste Tire Derived Carbon–Polymer Composite Paper as Pseudocapacitive Electrode with Long Cycle Life”), follows an ORNL discovery of a method to use scrap tires for batteries. Together, these approaches could provide some relief to the problems associated with the 1.5 billion tires manufacturers expect to produce annually by 2035.|
|“Those tires will eventually need to be discarded, and our supercapacitor applications can consume several tons of this waste,” Paranthaman said. “Combined with the technology we’ve licensed to two companies to convert scrap tires into carbon powders for batteries, we estimate consuming about 50 tons per day.”|
|While that amount represents just a fraction of the 8,000 tons that need to be recycled every day, co-author Yury Gogotsi of Drexel noted that other recycling companies could contribute to that goal.|
|“Each tire can produce carbon with a yield of about 50 percent with the ORNL process,” Gogotsi said. “If we were to recycle all of the scrap tires, that would translate into 1.5 million tons of carbon, which is half of the annual global production of graphite.”|
|To produce the carbon composite papers, the researchers soaked crumbs of irregularly shaped tire rubber in concentrated sulfuric acid. They then washed the rubber and put it into a tubular furnace under a flowing nitrogen gas atmosphere. They gradually increased the temperature from 400 degrees Celsius to 1,100 degrees.|
|After several additional steps, including mixing the material with potassium hydroxide and additional baking and washing with deionized water and oven drying, researchers have a material they could mix with polyaniline, an electrically conductive polymer, until they have a finished product.|
|“We anticipate that the same strategy can be applied to deposit other pseudocapacitive materials with low-cost tire-derived activated carbon to achieve even higher electrochemical performance and longer cycle life, a key challenge for electrochemically active polymers,” Gogotsi said.|
|Source: Oak Ridge National Laboratory|
21 Sep 2015
The scientists are using cellulose, an organic compound found in plants, bacteria, algae and trees, to build more efficient and longer-lasting energy storage devices or capacitors. This development paves the way toward the production of lightweight, flexible, and high-power electronics, such as wearable devices, portable power supplies and hybrid and electric vehicles.
“Ultimately the goal of this research is to find ways to power current and future technology with efficiency and in a sustainable way,” says Cranston, whose joint research was recently published in Advanced Materials. “This means anticipating future technology needs and relying on materials that are more environmentally friendly and not based on depleting resources.
Cellulose offers the advantages of high strength and flexibility for many advanced applications; of particular interest are nanocellulose-based materials. The work by Cranston, an assistant chemical engineering professor, and Zhitomirsky, a materials science and engineering professor, demonstrates an improved three-dimensional energy storage device constructed by trapping functional nanoparticles within the walls of a nanocellulose foam.
The foam is made in a simplified and fast one-step process. The type of nanocellulose used is called cellulose nanocrystals and looks like uncooked long-grain rice but with nanometer-dimensions. In these new devices, the ‘rice grains’ have been glued together at random points forming a mesh-like structure with lots of open space, hence the extremely lightweight nature of the material. This can be used to produce more sustainable capacitor devices with higher power density and faster charging abilities compared to rechargeable batteries.
Lightweight and high-power density capacitors are of particular interest for the development of hybrid and electric vehicles. The fast-charging devices allow for significant energy saving, because they can accumulate energy during braking and release it during acceleration.
“I believe that the best results can be obtained when researchers combine their expertise,” Zhitomirsky says. “Emily is an amazing research partner. I have been deeply impressed by her enthusiasm, remarkable ability to organize team work and generate new ideas.”
Explore further: Engineers craft new material for high-performing ‘supercapacitors’
More information: Cellulose Nanocrystal Aerogels as Universal 3D Lightweight Substrates for Supercapacitor Materials, DOI: 10.1002/adma.201502284