Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Battery boost

This schematic shows a silicon-carbon nanocomposite granule formed through a hierarchical bottom-up assembly process. Annealed carbon black particles are coated by silicon nanoparticles and then assembled into rigid spheres with open interconnected internal channels. Credit: Courtesy of Gleb Yushin
This schematic shows a silicon-carbon nanocomposite granule formed through a hierarchical bottom-up assembly process. Annealed carbon black particles are coated by silicon nanoparticles and then assembled into rigid spheres with open interconnected internal channels. Credit: Courtesy of Gleb Yushin

Abstract:
High-Performance Lithium-Ion Anode Uses "Bottom Up, Self-Assembled" Nanocomposite Materials to Increase Capacity

By John Toon

Battery boost

Atlanta, GA | Posted on March 15th, 2010

A new high-performance anode structure based on silicon-carbon nanocomposite materials could significantly improve the performance of lithium-ion batteries used in a wide range of applications from hybrid vehicles to portable electronics.

Produced with a "bottom-up" self-assembly technique, the new structure takes advantage of nanotechnology to fine-tune its materials properties, addressing the shortcomings of earlier silicon-based battery anodes. The simple, low-cost fabrication technique was designed to be easily scaled up and compatible with existing battery manufacturing.

Details of the new self-assembly approach were published online in the journal Nature Materials on March 14.

"Development of a novel approach to producing hierarchical anode or cathode particles with controlled properties opens the door to many new directions for lithium-ion battery technology," said Gleb Yushin, an assistant professor in the School of Materials Science and Engineering at the Georgia Institute of Technology. "This is a significant step toward commercial production of silicon-based anode materials for lithium-ion batteries."

The popular and lightweight batteries work by transferring lithium ions between two electrodes - a cathode and an anode - through a liquid electrolyte. The more efficiently the lithium ions can enter the two electrodes during charge and discharge cycles, the larger the battery's capacity will be.

Existing lithium-ion batteries rely on anodes made from graphite, a form of carbon. Silicon-based anodes theoretically offer as much as a ten-fold capacity improvement over graphite, but silicon-based anodes have so far not been stable enough for practical use.

Graphite anodes use particles ranging in size from 15 to 20 microns. If silicon particles of that size are simply substituted for the graphite, expansion and contraction as the lithium ions enter and leave the silicon creates cracks that quickly cause the anode to fail.

The new nanocomposite material solves that degradation problem, potentially allowing battery designers to tap the capacity advantages of silicon. That could facilitate higher power output from a given battery size - or allow a smaller battery to produce a required amount of power.

"At the nanoscale, we can tune materials properties with much better precision than we can at traditional size scales," said Yushin. "This is an example of where having nanoscale fabrication techniques leads to better materials."

Electrical measurements of the new composite anodes in small coin cells showed they had a capacity more than five times greater than the theoretical capacity of graphite.

Fabrication of the composite anode begins with formation of highly conductive branching structures - similar to the branches of a tree - made from carbon black nanoparticles annealed in a high-temperature tube furnace. Silicon nanospheres with diameters of less than 30 nanometers are then formed within the carbon structures using a chemical vapor deposition process. The silicon-carbon composite structures resemble "apples hanging on a tree."

Using graphitic carbon as an electrically-conductive binder, the silicon-carbon composites are then self-assembled into rigid spheres that have open, interconnected internal pore channels. The spheres, formed in sizes ranging from 10 to 30 microns, are used to form battery anodes. The relatively large composite powder size - a thousand times larger than individual silicon nanoparticles - allows easy powder processing for anode fabrication.

The internal channels in the silicon-carbon spheres serve two purposes. They admit liquid electrolyte to allow rapid entry of lithium ions for quick battery charging, and they provide space to accommodate expansion and contraction of the silicon without cracking the anode. The internal channels and nanometer-scale particles also provide short lithium diffusion paths into the anode, boosting battery power characteristics.

The size of the silicon particles is controlled by the duration of the chemical vapor deposition process and the pressure applied to the deposition system. The size of the carbon nanostructure branches and the size of the silicon spheres determine the pore size in the composite.

Production of the silicon-carbon composites could be scaled up as a continuous process amenable to ultra high-volume powder manufacturing, Yushin said. Because the final composite spheres are relatively large when they are fabricated into anodes, the self-assembly technique avoids the potential health risks of handling nanoscale powders, he added.

Once fabricated, the nanocomposite anodes would be used in batteries just like conventional graphite structures. That would allow battery manufacturers to adopt the new anode material without making dramatic changes in production processes.

So far, the researchers have tested the new anode through more than a hundred charge-discharge cycles. Yushin believes the material would remain stable for thousands of cycles because no degradation mechanisms have become apparent.

"If this technology can offer a lower cost on a capacity basis, or lighter weight compared to current techniques, this will help advance the market for lithium batteries," he said. "If we are able to produce less expensive batteries that last for a long time, this could also facilitate the adoption of many 'green' technologies, such as electric vehicles or solar cells."

In addition to Yushin, the paper's authors included Alexandre Magasinki, Patrick Dixon and Benjamin Hertzberg - all from Georgia Tech - and Alexander Kvit from the Materials Science Center and Materials Science Department at the University of Wisconsin-Madison, and Jorge Ayala from Superior Graphite. The paper also acknowledges the contributions of Alexander Alexeev at Georgia Tech and Igor Luzinov from Clemson University.

The research was partially supported by a Small Business Innovation Research (SBIR) grant from the National Aeronautics and Space Administration (NASA) to Chicago-based Superior Graphite and Atlanta-based Streamline Nanotechnologies, Inc.

####

About Georgia Institute of Technology
The Georgia Institute of Technology is one of the nation's top research universities, distinguished by its commitment to improving the human condition through advanced science and technology.

Georgia Tech's campus occupies 400 acres in the heart of the city of Atlanta, where 20,000 undergraduate and graduate students receive a focused, technologically based education.

For more information, please click here

Contacts:
John Toon

404-894-6986

Abby Vogel
404-385-3364

Copyright © Georgia Institute of Technology

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

Engineers show light can play seesaw at the nanoscale: Discovery is another step toward faster and more energy-efficient optical devices for computation and communication September 22nd, 2014

New chip promising for tumor-targeting research September 22nd, 2014

Twisted graphene chills out: When two sheets of graphene are stacked in a special way, it is possible to cool down the graphene with a laser instead of heating it up, University of Manchester researchers have shown September 22nd, 2014

New star-shaped molecule breakthrough: Scientists at The University of Manchester have generated a new star-shaped molecule made up of interlocking rings, which is the most complex of its kind ever created September 22nd, 2014

Govt.-Legislation/Regulation/Funding/Policy

Engineers show light can play seesaw at the nanoscale: Discovery is another step toward faster and more energy-efficient optical devices for computation and communication September 22nd, 2014

New chip promising for tumor-targeting research September 22nd, 2014

New star-shaped molecule breakthrough: Scientists at The University of Manchester have generated a new star-shaped molecule made up of interlocking rings, which is the most complex of its kind ever created September 22nd, 2014

SouthWest NanoTechnologies (SWeNT) Receives NIST Small Business Innovation Research (SBIR) Phase 1 Award to Produce Greater than 99% Semiconducting Single-Wall Carbon Nanotubes September 19th, 2014

Possible Futures

Air Force’s 30-year plan seeks 'strategic agility' August 1st, 2014

IBM Announces $3 Billion Research Initiative to Tackle Chip Grand Challenges for Cloud and Big Data Systems: Scientists and engineers to push limits of silicon technology to 7 nanometers and below and create post-silicon future July 10th, 2014

Virus structure inspires novel understanding of onion-like carbon nanoparticles April 10th, 2014

Local girl does good March 22nd, 2014

Academic/Education

Biosensors Get a Boost from Graphene Partnership: $5 Million Investment Supports Dozens of Jobs and Development of 300mm Fabrication Process and Wafer Transfer Facility September 18th, 2014

Malvern technology delivers Malvern reliability in multi-disciplinary lab at Queen Mary University London September 9th, 2014

State University of New York Trustees Unanimously Approve SUNY Polytechnic Institute (SUNY Poly) as New Name for Merged SUNY CNSE / SUNYIT September 9th, 2014

New Vice President Takes Helm at CNSE CMOST: Catherine Gilbert To Lead CNSE Children’s Museum of Science and Technology Through Expansion And Relocation August 29th, 2014

Self Assembly

Big Results Require Big Ambitions: Three young UCSB faculty receive CAREER awards from the National Science Foundation September 18th, 2014

Rice rolls 'neat' nanotube fibers: Rice University researchers' acid-free approach leads to strong conductive carbon threads September 15th, 2014

Molecular self-assembly controls graphene-edge configuration September 10th, 2014

Rice chemist wins rare NSF Special Creativity Award: Grant extension will bolster Zubarev's effort to produce gold nanorods September 8th, 2014

Discoveries

Engineers show light can play seesaw at the nanoscale: Discovery is another step toward faster and more energy-efficient optical devices for computation and communication September 22nd, 2014

New chip promising for tumor-targeting research September 22nd, 2014

Twisted graphene chills out: When two sheets of graphene are stacked in a special way, it is possible to cool down the graphene with a laser instead of heating it up, University of Manchester researchers have shown September 22nd, 2014

New star-shaped molecule breakthrough: Scientists at The University of Manchester have generated a new star-shaped molecule made up of interlocking rings, which is the most complex of its kind ever created September 22nd, 2014

Announcements

Engineers show light can play seesaw at the nanoscale: Discovery is another step toward faster and more energy-efficient optical devices for computation and communication September 22nd, 2014

New chip promising for tumor-targeting research September 22nd, 2014

Twisted graphene chills out: When two sheets of graphene are stacked in a special way, it is possible to cool down the graphene with a laser instead of heating it up, University of Manchester researchers have shown September 22nd, 2014

New star-shaped molecule breakthrough: Scientists at The University of Manchester have generated a new star-shaped molecule made up of interlocking rings, which is the most complex of its kind ever created September 22nd, 2014

Energy

Iranian Researchers Synthesize Stable Ceramic Nanopowders at Room Temperature September 20th, 2014

IEEE International Electron Devices Meeting To Celebrate 60th Anniversary as The Leading Technical Conference for Advanced Semiconductor Devices September 18th, 2014

Rice rolls 'neat' nanotube fibers: Rice University researchers' acid-free approach leads to strong conductive carbon threads September 15th, 2014

Simple, Cost-Effective Method Proposed for Synthesizing Zinc Oxide Nanopigments September 15th, 2014

Automotive/Transportation

Next-Gen Luxury RV From Global Caravan Technologies Will Offer MagicView Roof and Windshield Using SPD-SmartGlass Technology From Research Frontiers: Recreational Vehicle Manufacturer Global Caravan Technologies (GCT) Features 28 Square Feet of MagicView™ SPD-SmartGlass September 17th, 2014

Toward making lithium-sulfur batteries a commercial reality for a bigger energy punch September 17th, 2014

Nanoribbon film keeps glass ice-free: Rice University lab refines deicing film that allows radio frequencies to pass September 16th, 2014

‘Small’ transformation yields big changes September 16th, 2014

Battery Technology/Capacitors/Generators/Piezoelectrics/Thermoelectrics

IEEE International Electron Devices Meeting To Celebrate 60th Anniversary as The Leading Technical Conference for Advanced Semiconductor Devices September 18th, 2014

Toward making lithium-sulfur batteries a commercial reality for a bigger energy punch September 17th, 2014

NEI Corporation and PneumatiCoat Technologies Sign Agreement to Jointly Develop and Market New Materials for Lithium-ion Batteries September 12th, 2014

UT Arlington research uses nanotechnology to help cool electrons with no external sources September 11th, 2014

Research partnerships

Biosensors Get a Boost from Graphene Partnership: $5 Million Investment Supports Dozens of Jobs and Development of 300mm Fabrication Process and Wafer Transfer Facility September 18th, 2014

The Pocket Project will develop a low-cost and accurate point-of-care test to diagnose Tuberculosis: ICN2 holds a follow-up meeting of the Project on September 18th - 19th September 18th, 2014

Recruiting bacteria to be technology innovation partners: September 17th, 2014

Carbon Sciences Developing Breakthrough Technology to Mass-Produce Graphene -- the New Miracle Material: Company Enters Into an Agreement With the University of California, Santa Barbara (UCSB) to Fund the Further Development of a New Graphene Process September 16th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE