Yarns of niobium nanowire can make supercapacitors to provide a surge of energy when it’s needed
Wearable electronic devices for health and fitness monitoring are a rapidly growing area of consumer electronics; one of their biggest limitations is the capacity of their tiny batteries to deliver enough power to transmit data. Now, researchers at MIT and in Canada have found a promising new approach to delivering the short but intense bursts of power needed by such small devices.
The key is a new approach to making supercapacitors — devices that can store and release electrical power in such bursts, which are needed for brief transmissions of data from wearable devices such as heart-rate monitors, computers, or smartphones, the researchers say. They may also be useful for other applications where high power is needed in small volumes, such as autonomous microrobots.
The new approach uses yarns, made from nanowires of the element niobium, as the electrodes in tiny supercapacitors (which are essentially pairs of electrically conducting fibers with an insulator between). The concept is described in a paper in the journal ACS Applied Materials and Interfaces by MIT professor of mechanical engineering Ian W. Hunter, doctoral student Seyed M. Mirvakili, and three others at the University of British Columbia.
Nanotechnology researchers have been working to increase the performance of supercapacitors for the past decade. Among nanomaterials, carbon-based nanoparticles — such as carbon nanotubes and graphene — have shown promising results, but they suffer from relatively low electrical conductivity, Mirvakili says.
In this new work, he and his colleagues have shown that desirable characteristics for such devices, such as high power density, are not unique to carbon-based nanoparticles, and that niobium nanowire yarn is a promising an alternative.
“Imagine you’ve got some kind of wearable health-monitoring system,” Hunter says, “and it needs to broadcast data, for example using Wi-Fi, over a long distance.” At the moment, the coin-sized batteries used in many small electronic devices have very limited ability to deliver a lot of power at once, which is what such data transmissions need.
“Long-distance Wi-Fi requires a fair amount of power,” says Hunter, the George N. Hatsopoulos Professor in Thermodynamics in MIT’s Department of Mechanical Engineering, “but it may not be needed for very long.” Small batteries are generally poorly suited for such power needs, he adds.
“We know it’s a problem experienced by a number of companies in the health-monitoring or exercise-monitoring space. So an alternative is to go to a combination of a battery and a capacitor,” Hunter says: the battery for long-term, low-power functions, and the capacitor for short bursts of high power. Such a combination should be able to either increase the range of the device, or — perhaps more important in the marketplace — to significantly reduce size requirements.
The new nanowire-based supercapacitor exceeds the performance of existing batteries, while occupying a very small volume. “If you’ve got an Apple Watch and I shave 30 percent off the mass, you may not even notice,” Hunter says. “But if you reduce the volume by 30 percent, that would be a big deal,” he says: Consumers are very sensitive to the size of wearable devices.
The innovation is especially significant for small devices, Hunter says, because other energy-storage technologies — such as fuel cells, batteries, and flywheels — tend to be less efficient, or simply too complex to be practical when reduced to very small sizes. “We are in a sweet spot,” he says, with a technology that can deliver big bursts of power from a very small device.
Ideally, Hunter says, it would be desirable to have a high volumetric power density (the amount of power stored in a given volume) and high volumetric energy density (the amount of energy in a given volume). “Nobody’s figured out how to do that,” he says. However, with the new device, “We have fairly high volumetric power density, medium energy density, and a low cost,” a combination that could be well suited for many applications.
Niobium is a fairly abundant and widely used material, Mirvakili says, so the whole system should be inexpensive and easy to produce. “The fabrication cost is cheap,” he says. Other groups have made similar supercapacitors using carbon nanotubes or other materials, but the niobium yarns are stronger and 100 times more conductive. Overall, niobium-based supercapacitors can store up to five times as much power in a given volume as carbon nanotube versions.
Niobium also has a very high melting point — nearly 2,500 degrees Celsius — so devices made from these nanowires could potentially be suitable for use in high-temperature applications.
In addition, the material is highly flexible and could be woven into fabrics, enabling wearable forms; individual niobium nanowires are just 140 nanometers in diameter — 140 billionths of a meter across, or about one-thousandth the width of a human hair.
Read more: Tiny wires could provide a big energy boost
The Latest on: Nanowire supercapacitors
[google_news title=”” keyword=”nanowire supercapacitors” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Nanowire supercapacitors
- Acids enable adhesive electrodes for thin, flexible supercapacitorson April 1, 2024 at 9:11 am
More information: Chuanling Mu et al, Taming of heteropoly acids into adhesive electrodes using amino acids for the development of flexible two-dimensional supercapacitors, Polyoxometalates (2024 ...
- Acids enable adhesive electrodes for thin, flexible supercapacitorson March 31, 2024 at 5:00 pm
They published their findings on Mar. 29, 2024 in Polyoxometalates. "Flexible 2D supercapacitors typically suffer from complicated and time-consuming fabrication procedures and poor mechanical ...
- Global Nanowire Battery Market Size To Exceed USD 986.35 Million By 2033 | CAGR Of 33.42%on March 17, 2024 at 5:00 pm
New York, United States , March 18, 2024 (GLOBE NEWSWIRE) -- The Global Nanowire Battery Market Size is to Grow from USD 55.18 Million in 2023 to USD 986.35 Million by 2033, at a Compound Annual ...
- SuperCapacitors Vs Batteries Againon December 2, 2021 at 4:16 am
Supercapacitors are definitely not the same as batteries, we all know that. They tend to have a very low operating voltage, and due to their operating principle of storing charge on parallel ...
- Nanowire photonicson November 30, 2021 at 12:28 pm
This has led to a host of nanowire photonic devices including photodetectors, chemical and gas sensors, waveguides, LEDs, microcavity lasers, solar cells and nonlinear optical converters.
- What are ultracapacitors and supercapacitors?on October 13, 2021 at 12:42 pm
These characteristics makes supercapacitors very suitable for applications in consumer electronics, hybrid electric vehicles and industrial power management. Batteries and ultracapacitors are ...
- Nanowire Animation (IMAGE)on September 12, 2021 at 6:44 am
This animation shows molecular building blocks joining the tip of a growing nanowire. Each block consists of a diamondoid -- the smallest possible bit of diamond -- attached to sulfur and copper ...
- What Are ‘Supercapacitors’ And What Are They Doing In Lamborghini’s New Sián Supercar?on September 6, 2019 at 2:00 pm
But back to the Sián and those “supercapacitors.” It’s pretty much what is sounds like: Really BIG capacitors that store a lot of energy and are then able to dump it quickly into something ...
- Worldwide Nanowire Supplierson September 10, 2017 at 11:47 am
Nanowires are ultrafine wires or linear arrays of dots, formed by self-assembly. They can be made from a wide range of materials. Semiconductor nanowires made of silicon, gallium nitride and indium ...
- Powering A Laptop With Supercapacitorson March 3, 2017 at 4:48 pm
What do you do when you find a small horde of supercapacitors? The correct answer is a spectrum of dangerous devices ranging from gauss guns to quarter shrinkers. [Rinoa] had a less destructive ...
via Bing News