Green Car Congress  
Go to GCC Discussions forum About GCC Contact  RSS Subscribe Twitter headlines

« Singapore invests $63M in fuel cell company Intelligent Energy | Main | DOE authorizes Jordan Cove LNG export project »

Print this post

New fragmented carbon nanotube adhesive conductor could eliminate need for binders in Li-ion electrodes

24 March 2014

A team of researchers at the University of Delaware has discovered a “sticky” conductive material that may eliminate the need for binders in Li-ion battery electrodes. Bingqing Wei, professor of mechanical engineering and doctoral student Zeyuan Cao recently discovered that fragmented carbon nanotube macrofilms (FCNT) can serve as adhesive conductors, combining two functions in one material. Their work is reported in ACS Nano, and they have filed a patent application on the discovery.

The problem with the current technology is that the binders impair the electrochemical performance of the battery because of their insulating properties. Furthermore, the organic solvents used to mix the binders and conductive materials together not only add to the expense of the final product, but also are toxic to humans.

—Bingqing Wei

FCNTs are web-like meshes with “tentacles” that are coupled with active lithium-based cathode and anode materials. They are then assembled using simple ultrasound processing. The process employs no organic solvents.

The adhesive FCNT conductors provide not only a high electrical conductivity but also a strong adhesive force, functioning simultaneously as both the conductive additives and the binder materials for lithium-ion batteries. Such composite electrodes exhibit superior high-rate and retention capabilities compared to the electrodes using a conventional binder (PVDF) and a conductive additive (CB).

An in situ tribology method combining wear track imaging and force measurement is employed to evaluate the adhesion strength of the adhesive FCNT conductors. The adhesive FCNT conductors exhibit higher adhesion strength than PVDF. It has further been confirmed that the adhesive FCNT conductor can be used in both cathodes and anodes and is proved to be a competent substitute for polymer binders to maintain mechanical integrity and at the same time to provide electrical connectivity of active materials in the composite electrodes. The organic-solvent-free electrode manufacturing offers a promising strategy for the battery industry.

—Cao and Wei (2014)

The approach could also be employed for electrode preparation for other energy storage devices such as electrochemical capacitors.

Resources

  • Zeyuan Cao and Bingqing Wei (2014) “Fragmented Carbon Nanotube Macrofilms as Adhesive Conductors for Lithium-Ion Batteries,” ACS Nano doi: 10.1021/nn500585g

March 24, 2014 in Brief | Permalink | Comments (3) | TrackBack (0)

TrackBack

TrackBack URL for this entry:
http://www.typepad.com/services/trackback/6a00d8341c4fbe53ef01a5118d5ae1970c

Listed below are links to weblogs that reference New fragmented carbon nanotube adhesive conductor could eliminate need for binders in Li-ion electrodes:

Comments

"Polymer binders such as poly(vinylidene fluoride) (PVDF) and conductive additives such as carbon black (CB) are indispensable components for manufacturing battery electrodes..."

http://www.ncbi.nlm.nih.gov/pubmed/24564355

Scientists have come up with quite a few ways to make lithium ion batteries, from anodes to electrolytes to cathodes to binders, they have stayed ahead of the curve.

One more technology to improve future batteries?

More effective future solid states batteries may use a similar technology to bind electrode together while doing without current electrolytes.

Harvey,

That is the idea. If you read technical papers and I have, you see that many types of binders, cathode, anodes and electrolytes have been tried with various results. Solid state seems to be the trend, as soon as they can get performance, longevity and price in line.

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Working...
Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.

Working...

Post a comment

Green Car Congress © 2013 BioAge Group, LLC. All Rights Reserved. | Home | BioAge Group