Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Flexible supercapacitor raises bar for volumetric energy density: Could be woven into clothes to power wearable medical, communications devices

Abstract:
Scientists have taken a large step toward making a fiber-like energy storage device that can be woven into clothing and power wearable medical monitors, communications equipment or other small electronics.

Flexible supercapacitor raises bar for volumetric energy density: Could be woven into clothes to power wearable medical, communications devices

Cleveland, OH | Posted on May 12th, 2014

The device is a supercapacitor—a cousin to the battery. This one packs an interconnected network of graphene and carbon nanotubes so tightly that it stores energy comparable to some thin-film lithium batteries—an area where batteries have traditionally held a large advantage.

The product's developers, engineers and scientists at Nanyang Technological University (NTU) in Singapore, Tsinghua University in China, and Case Western Reserve University in the United States, believe the storage capacity by volume (called volumetric energy density) is the highest reported for carbon-based microscale supercapacitors to date: 6.3 microwatt hours per cubic millimeter.

The device also maintains the advantage of charging and releasing energy much faster than a battery. The fiber-structured hybrid materials offer huge accessible surface areas and are highly conductive.

The researchers have developed a way to continuously produce the flexible fiber, enabling them to scale up production for a variety of uses. To date, they've made 50-meter long fibers, and see no limits on length.

They envision the fiber supercapacitor could be woven into clothing to power medical devices for people at home, or communications devices for soldiers in the field. Or, they say, the fiber could be a space-saving power source and serve as "energy-carrying wires" in medical implants.

Yuan Chen, a professor of chemical engineering at NTU led the new study, working with Dingshan Yu, Kunli Goh, Hong Wang, Li Wei and Wenchao Jiang at NTU; Qiang Zhang at Tsinghua; and Liming Dai at Case Western Reserve. The scientists report their research in Nature Nanotechnology: http://dx.doi.org/10.1038/nnano.2014.93.

Dai, a professor of macromolecular science and engineering at Case Western Reserve and a co-author of the paper, explained that most supercapacitors have high power density but low energy density, which means they can charge quickly and give a boost of power, but don't last long. Conversely, batteries have high energy density and low power density, which means they can last a long time, but don't deliver a large amount of energy quickly.

Microelectronics to electric vehicles can benefit from energy storage devices that offer high power and high energy density. That's why researchers are working to develop a device that offers both.

To continue to miniaturize electronics, industry needs tiny energy storage devices with large volumetric energy densities.

By mass, supercapacitors might have comparable energy storage, or energy density, to batteries. But because they require large amounts of accessible surface area to store energy, they have always lagged badly in energy density by volume.

Their approach

To improve the energy density by volume, the researchers designed a hybrid fiber.

A solution containing acid-oxidized single-wall nanotubes, graphene oxide and ethylenediamine, which promotes synthesis and dopes graphene with nitrogen, is pumped through a flexible narrow reinforced tube called a capillary column and heated in an oven for six hours.

Sheets of graphene, one to a few atoms thick, and aligned, single-walled carbon nanotubes self-assemble into an interconnected prorous network that run the length of the fiber.

The arrangement provides huge amounts of accessible surface area—396 square meters per gram of hybrid fiber—for the transport and storage of charges.

But the materials are tightly packed in the capillary column and remain so as they're pumped out, resulting in the high volumetric energy density.

The process using multiple capillary columns will enable the engineers to make fibers continuously and maintain consistent quality, Chen said.

The findings

The researchers have made fibers as long as 50 meters and found they remain flexible with high capacity of 300 Farad per cubic centimeter.

In testing, they found that three pairs of fibers arranged in series tripled the voltage while keeping the charging/discharging time the same.

Three pairs of fibers in parallel tripled the output current and tripled the charging/discharging time, compared to a single fiber operated at the same current density.

When they integrate multiple pairs of fibers between two electrodes, the ability to store electricity, called capacitance, increased linearly according to the number of fibers used.

Using a polyvinyl alcohol /phosphoric acid gel as an electrolyte, a solid-state micro-supercapacitor made from a pair of fibers offered a volumetric density of 6.3 microwatt hours per cubic millimeter, which is comparable to that of a 4-volt-500-microampere-hour thin film lithium battery.

The fiber supercapacitor demonstrated ultrahigh energy-density value, while maintaining the high power density and cycle stability.

"We have tested the fiber device for 10,000 charge/discharge cycles, and the device retains about 93 percent of its original performance," Yu said, " while conventional rechargeable batteries have a lifetime of less than 1000 cycles."

The team also tested the device for flexible energy storage. The device was subjected to constant mechanical stress and its performance was evaluated. "The fiber supercapacitor continues to work without performance loss, even after bending hundreds of times," Yu said.

"Because they remain flexible and structurally consistent over their length, the fibers can also be woven into a crossing pattern into clothing for wearable devices in smart textiles." Chen said.

Such clothing could power biomedical monitoring devices a patient wears at home, providing information to a doctor at a hospital, Dai said. Woven into uniforms, the battery-like supercapacitors could power displays or transistors used for communication.

The researchers are now expanding their efforts. They plan to scale up the technology for low-cost, mass production of the fibers aimed at commercializing high-performance micro-supercapacitors.

In addition, "The team is also interested in testing these fibers for multifunctional applications, including batteries, solar cells, biofuel cells, and sensors for flexible and wearable optoelectronic systems," Dai said. "Thus, we have opened up many possibilities and still have a lot to do."

###

The Ministry of Education, Singapore and Asian Office of Aerospace Research and Development of the U.S. Air Force and the U.S, Air Force Office of Scientific Research funded the research.

####

For more information, please click here

Contacts:
Kevin Mayhood

216-368-4442

Copyright © Case Western Reserve University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

No need in supercomputers: Russian scientists suggest a PC to solve complex problems tens of times faster than with massive supercomputers June 30th, 2016

Surprising qualities of insulator ring surfaces: Surface phenomena in ring-shaped topological insulators are just as controllable as those in spheres made of the same material June 30th, 2016

How cancer cells spread and squeeze through tiny blood vessels (video) June 30th, 2016

Oxford Instruments and Dresden High Magnetic Field Laboratory collaborate to develop HTS magnet technology components for high field superconducting magnet systems June 29th, 2016

Graphene/ Graphite

Surprising qualities of insulator ring surfaces: Surface phenomena in ring-shaped topological insulators are just as controllable as those in spheres made of the same material June 30th, 2016

Thin films

Novel capping strategy improves stability of perovskite nanocrystals: Study addresses instability issues with organometal-halide perovskites, a promising class of materials for solar cells, LEDs, and other applications June 13th, 2016

New nanomaterial offers promise in bendable, wearable electronic devices: Electroplated polymer makes transparent, highly conductive, ultrathin film June 13th, 2016

Perovskite solar cells surpass 20 percent efficiency: EPFL researchers are pushing the limits of perovskite solar cell performance by exploring the best way to grow these crystals June 13th, 2016

NRL develops new low-defect method to nitrogen dope graphene resulting in tunable bandstructure June 6th, 2016

Govt.-Legislation/Regulation/Funding/Policy

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

How cancer cells spread and squeeze through tiny blood vessels (video) June 30th, 2016

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Ultrathin, flat lens resolves chirality and color: Multifunctional lens could replace bulky, expensive machines June 25th, 2016

Nanotubes/Buckyballs/Fullerenes

Nanotubes' 'stuffing' as is: A scientist from the Lomonosov Moscow State University studied the types of carbon nanotubes' 'stuffing' June 2nd, 2016

Programmable materials find strength in molecular repetition May 23rd, 2016

Nanotubes are beacons in cancer-imaging technique: Rice University researchers use spectral triangulation to pinpoint location of tumors May 21st, 2016

Unveiling the electron's motion in a carbon nanocoil: Development of a precise resistivity measurement system for quasi-one-dimensional nanomaterials using a focused ion beam May 16th, 2016

Nanomedicine

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

How cancer cells spread and squeeze through tiny blood vessels (video) June 30th, 2016

Building a smart cardiac patch: 'Bionic' cardiac patch could one day monitor and respond to cardiac problems June 28th, 2016

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Sensors

Researchers discover new chemical sensing technique: Technique allows sharper detail -- and more information -- with near infrared light June 24th, 2016

Artificial synapse rivals biological ones in energy consumption June 21st, 2016

A new form of hybrid photodetectors with quantum dots and graphene June 19th, 2016

Drum beats from a one atom thick graphite membrane June 15th, 2016

Discoveries

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

No need in supercomputers: Russian scientists suggest a PC to solve complex problems tens of times faster than with massive supercomputers June 30th, 2016

Surprising qualities of insulator ring surfaces: Surface phenomena in ring-shaped topological insulators are just as controllable as those in spheres made of the same material June 30th, 2016

How cancer cells spread and squeeze through tiny blood vessels (video) June 30th, 2016

Announcements

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

No need in supercomputers: Russian scientists suggest a PC to solve complex problems tens of times faster than with massive supercomputers June 30th, 2016

Surprising qualities of insulator ring surfaces: Surface phenomena in ring-shaped topological insulators are just as controllable as those in spheres made of the same material June 30th, 2016

How cancer cells spread and squeeze through tiny blood vessels (video) June 30th, 2016

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

No need in supercomputers: Russian scientists suggest a PC to solve complex problems tens of times faster than with massive supercomputers June 30th, 2016

Surprising qualities of insulator ring surfaces: Surface phenomena in ring-shaped topological insulators are just as controllable as those in spheres made of the same material June 30th, 2016

Building a smart cardiac patch: 'Bionic' cardiac patch could one day monitor and respond to cardiac problems June 28th, 2016

Military

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Ultrathin, flat lens resolves chirality and color: Multifunctional lens could replace bulky, expensive machines June 25th, 2016

Scientists engineer tunable DNA for electronics applications June 21st, 2016

Marrying superconductors, lasers, and Bose-Einstein condensates: Chapman University Institute for Quantum Studies (IQS) member Yutaka Shikano, Ph.D., recently had research published in Scientific Reports June 20th, 2016

Textiles/Clothing

Weird, water-oozing material could help quench thirst: Nanorods' behavior first theorized 20 years ago, but not seen until now June 13th, 2016

Programmable materials find strength in molecular repetition May 23rd, 2016

The impact of anti-odor clothing on the environment March 31st, 2016

No more washing: Nano-enhanced textiles clean themselves with light: New technique to grow nanostructures that degrade organic matter when exposed to light March 23rd, 2016

Battery Technology/Capacitors/Generators/Piezoelectrics/Thermoelectrics/Energy storage

Texas A&M Chemist Says Trapped Electrons To Blame For Lack Of Battery Efficiency: Forget mousetraps — today’s scientists will get the cheese if they manage to build a better battery June 28th, 2016

Yale researchers’ technology turns wasted heat into power June 27th, 2016

Stanford researchers find new ways to make clean hydrogen and rechargable zinc batteries June 18th, 2016

Efficient hydrogen production made easy: Sticking electrons to a semiconductor with hydrazine creates an electrocatalyst June 17th, 2016

Research partnerships

Superheroes are real: Ultrasensitive nonlinear metamaterials for data transfer June 25th, 2016

Soft decoupling of organic molecules on metal June 23rd, 2016

FEI and University of Liverpool Announce QEMSCAN Research Initiative: University of Liverpool will utilize FEI’s QEMSCAN technology to gain a better insight into oil and gas reserves & potentially change the approach to evaluating them June 22nd, 2016

Tailored DNA shifts electrons into the 'fast lane': DNA nanowire improved by altering sequences June 22nd, 2016

Solar/Photovoltaic

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

New generation of high-efficiency solar thermal absorbers developed June 20th, 2016

Novel capping strategy improves stability of perovskite nanocrystals: Study addresses instability issues with organometal-halide perovskites, a promising class of materials for solar cells, LEDs, and other applications June 13th, 2016

Perovskite solar cells surpass 20 percent efficiency: EPFL researchers are pushing the limits of perovskite solar cell performance by exploring the best way to grow these crystals June 13th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic