Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button

Home > Press > Add boron for better batteries: Rice University theorists say graphene-boron mix shows promise for lithium-ion batteries

A theory developed at Rice University determined that a graphene/boron compound would excel as an ultrathin anode for lithium-ion batteries. The compound would store far more energy than graphite electrodes used in current batteries. Credit: Vasilii Artyukhov/Rice University
A theory developed at Rice University determined that a graphene/boron compound would excel as an ultrathin anode for lithium-ion batteries. The compound would store far more energy than graphite electrodes used in current batteries.

Credit: Vasilii Artyukhov/Rice University

Abstract:
Frustration led to revelation when Rice University scientists determined how graphene might be made useful for high-capacity batteries.

Add boron for better batteries: Rice University theorists say graphene-boron mix shows promise for lithium-ion batteries

Houston, TX | Posted on May 17th, 2013

Calculations by the Rice lab of theoretical physicist Boris Yakobson found a graphene/boron anode should be able to hold a lot of lithium and perform at a proper voltage for use in lithium-ion batteries. The discovery appears in the American Chemical Society's Journal of Physical Chemistry Letters.

The possibilities offered by graphene get clearer by the day as labs around the world grow and test the one-atom-thick form of carbon. Because it is as thin as possible, battery manufacturers hope to take advantage of graphene's massive surface area to store lithium ions. Counting both sides of the material, one gram would cover 2,630 square meters, or nearly half a football field.

But there's a problem. The ions don't stick to graphene very well.

"As often happens with graphene, people oversold how wonderful it would be to absorb lithium," said Yakobson, whose group analyzes relationships between atoms based on their intrinsic energy. "But in experiments, they couldn't see it, and they were frustrated."

Scientists at the Honda Research Institute, who are interested in powerful batteries for electric cars, asked Yakobson to view the situation. "We looked at the theoretical capacity of an ideal sheet of graphene, and then how it could or could not benefit from curvature (into a nanotube) or topological defects. Our initial expectation was that it would improve lithium binding.

"But the theory didn't show any significant improvement," he said. "I was disappointed, but the experimentalists were satisfied because now their observations made sense."

Calculations involving graphene with defects, in which the honeycomb array is disrupted by five- and seven-atom polygons, fared no better. "So we decided to explore defects of different types where we replace some carbon atoms with another element that creates more attractive sites for lithium," he said. "And boron is one of them."

A carbon/boron compound in which a quarter of the carbon atoms are replaced by boron turned out to be nearly ideal as a way to activate graphene's ability to store lithium, Yakobson said. Boron attracts lithium ions into the matrix, but not so strongly that they can't be pulled away from a carbon/boron anode by a more attractive cathode.

"Having boron in the lattice gives very nice binding, so the capacity is good enough, two times larger than graphite," the most commonly used electrode in commercial lithium-ion batteries, he said. "At the same time, the voltage is also right."

Yakobson and Rice graduate student Yuanyue Liu, first author of the paper, calculated that a fully lithiated sheet of two-dimensional graphene/boron would have a capacity of 714 milliamp hours per gram. That translates to an energy density of 2,120 watt-hours per kilogram, far greater than graphite, when paired with a commercial lithium cobalt oxide cathode. They also determined the material would not radically expand or contract as it charges and discharges.

"In this case, it seems quite reasonable and exceeds -- theoretically, at least -- what is available now," Yakobson said.

An important step will be to find a way to synthesize the carbon/boron compound in large quantities. "It does exist, but it's not commercially available," he said.

Co-authors of the paper are Rice research associate Vasilii Artyukhov, Rice graduate student Mingjie Liu and Avetik Harutyunyan, a chief scientist at the Honda Research Institute.

The Honda Research Institute and the Department of Energy (DOE) supported the research. Computations were performed on the Rice DAVinCI system and the National Institute for Computational Sciences Kraken, both funded by the National Science Foundation, and the National Energy Research Scientific Computing Center Hopper, supported by the DOE.

####

About Rice University
Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation's top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is home to the Baker Institute for Public Policy. With 3,708 undergraduates and 2,374 graduate students, Rice's undergraduate student-to-faculty ratio is 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice has been ranked No. 1 for best quality of life multiple times by the Princeton Review and No. 2 for "best value" among private universities by Kiplinger's Personal Finance. To read "What they're saying about Rice," go to tinyurl.com/AboutRiceU.

For more information, please click here

Contacts:
David Ruth
713-348-6327


Mike Williams
713-348-6728

Copyright © Rice 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 Links

Read the abstract at:

Yakobson Group:

Honda Research Institute:

Related News Press

News and information

Scientists change properties of zeolites to improve hemodialysis July 29th, 2016

Novel state of matter: Observation of a quantum spin liquid July 29th, 2016

A new type of quantum bits July 29th, 2016

Lonely atoms, happily reunited July 29th, 2016

Beating the heat a challenge at the nanoscale: Rice University scientists detect thermal boundary that hinders ultracold experiments July 28th, 2016

Graphene/ Graphite

Dirty to drinkable: Engineers develop novel hybrid nanomaterials to transform water July 28th, 2016

Thomas Swan and NGI announce unique partnership July 28th, 2016

New nontoxic process promises larger ultrathin sheets of 2-D nanomaterials July 27th, 2016

Govt.-Legislation/Regulation/Funding/Policy

A new type of quantum bits July 29th, 2016

Thomas Swan and NGI announce unique partnership July 28th, 2016

Penn team uses nanoparticles to break up plaque and prevent cavities July 28th, 2016

Beating the heat a challenge at the nanoscale: Rice University scientists detect thermal boundary that hinders ultracold experiments July 28th, 2016

Discoveries

Scientists change properties of zeolites to improve hemodialysis July 29th, 2016

Novel state of matter: Observation of a quantum spin liquid July 29th, 2016

A new type of quantum bits July 29th, 2016

Lonely atoms, happily reunited July 29th, 2016

Announcements

Scientists change properties of zeolites to improve hemodialysis July 29th, 2016

Novel state of matter: Observation of a quantum spin liquid July 29th, 2016

A new type of quantum bits July 29th, 2016

Lonely atoms, happily reunited July 29th, 2016

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

Scientists change properties of zeolites to improve hemodialysis July 29th, 2016

Novel state of matter: Observation of a quantum spin liquid July 29th, 2016

A new type of quantum bits July 29th, 2016

Lonely atoms, happily reunited July 29th, 2016

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

New nontoxic process promises larger ultrathin sheets of 2-D nanomaterials July 27th, 2016

New lithium-oxygen battery greatly improves energy efficiency, longevity: New chemistry could overcome key drawbacks of lithium-air batteries July 26th, 2016

An accelerated pipeline to open materials research: ORNL workflow system unites imaging, algorithms, and HPC to advance materials discovery and design July 24th, 2016

Synthesized microporous 3-D graphene-like carbons: IBS research team create carbon synthesis using zeolites as a template July 1st, 2016

Grants/Awards/Scholarships/Gifts/Contests/Honors/Records

Penn team uses nanoparticles to break up plaque and prevent cavities July 28th, 2016

Beating the heat a challenge at the nanoscale: Rice University scientists detect thermal boundary that hinders ultracold experiments July 28th, 2016

Scientists test nanoparticle drug delivery in dogs with osteosarcoma July 26th, 2016

Ultra-flat circuits will have unique properties: Rice University lab studies 2-D hybrids to see how they differ from common electronics July 25th, 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