Defense

July 15, 2013

Air Force supports new generation of lithium-ion batteries

A few months back, the Air Force Office of Scientific Research was proud to publish an article regarding a research accomplishment by Dr. Jim Tour and his research team at Rice University.

AFOSR, along with other funding agencies, supported Dr. Tour’s research effort to make graphene suitable for a variety of organic chemistry applications – especially the promise of advanced chemical sensors, nanoscale electronic circuits and metamaterials.

Four years ago, Tour’s research team demonstrated that they could chemically unzip cylindrical shaped carbon nanotubes into soluble graphene nanoribbons without compromising the electronic properties of the graphitic structure. A recent paper by the Tour team, published in IEEE Spectrum and partially funded by AFOSR, showed that GNR can significantly increase the storage capacity of lithium ion (Li-ion) by combining graphene nanoribbons with tin oxide.

By producing GNR in bulk, a necessary requirement for making this a viable process, the Tour team mixes GNR and 10 nanometer wide particles of tin oxide to create a slurry. By adding a cellulose gum binding agent and water, the mixture is then applied to a capacitor, which is then fitted to a button-style lithium-ion battery.

In the Tour lab tests, the prototype battery had an initial charge capacity of more than 1,520 milliamp hours per gram (mAh/g). After repeated charge-discharge cycles that number began to plateau at about 825 mAh/g, but after 50 discharge cycles, the batteries retained far more capacity – more than double – that of Li-ion batteries that employ standard graphite anodes.

The critical key that makes the increase in battery capacity possible is the significant improvement in flexibility that graphene nanoribbons lend to the anode. By comparison, conventional Li-ion batteries with graphite anodes break down and lose efficiency because of their inability to flex, as they expand and contract, with repeated charge and discharge cycles; over time the graphite cracks and the battery cannot charge. Conversely, anodes with a graphene nanoribbon platform allow the tin oxide particles to maintain a consistent size, rather than expanding and contracting, and thus eliminating the brittleness and cracking associated with a graphite-based anode.

This breakthrough may very well lead to the next generation of the lithium-ion battery – a promising new platform for creating more durable, lightweight and efficient lithium-ion power.

 




All of this week's top headlines to your email every Friday.


 
 

 
CAE photograph

MH-60R FMS team supports Royal Australian Navy

CAE photograph A military representative ìfliesî the MH-60R Seahawk tactical operational flight trainer over Sydney, Australia, during a recent simulation event. In February, the Royal Australian Navy procured a trainer, simi...
 
 
marines-F35

U.S. Marine Corps begins F-35B operational trials

Six U.S. Marine Corps F-35B Lightning II jet aircraft arrived May 18 aboard the USS WASP off the coast of the United States’ Eastern Seaboard to mark the beginning of the first shipboard phase of the F-35B Operational Tes...
 
 
Navy photograph by Seaman Shelby M. Tucker

Navy declares IOC capability for new rolling airframe missile

Navy photograph by Seaman Shelby M. Tucker The amphibious transport dock ship USS Arlington (LPD 24) participates in training exercises with the amphibious assault ship USS Iwo Jima (LHD 7). Iwo Jima is underway conducting aqmp...
 

 
Huntington Ingalls Industries photograph by Ricky Thompson

Navy lays keel for PCU Indiana

Huntington Ingalls Industries photograph by Ricky Thompson A welder carves the initials of ship’s sponsor Diane Donald on a metal plate during the keel laying ceremony for the future Virginia-class attack submarine Indian...
 
 
Air Force photograph by PO2 Aidan P. Campbell

Navy announces successful test of EMLS

Air Force photograph by PO2 Aidan P. Campbell The aircraft carrier Pre-Commissioning Unit Gerald R. Ford (CVN 78) transits the James River during the ship’s launch and transit to Newport News Shipyard pier three for the f...
 
 
Air Force photograph by A1C Ryan Conroy

Air Commandos bid farewell to MC-130P Combat Shadows

Air Force photograph by A1C Ryan Conroy Two MC-130P Combat Shadows fly by during their final flight May 15, 2015, at Hurlburt Field, Fla. The final two Combat Shadows in the Air Force landed for the last time here in front of m...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>