July 27, 1997-Vol28n35: Process developed at UB makes batteries better

Process developed at UB makes batteries better

By CHRISTINE VIDAL
Reporter Editor

Researchers at UB have devised a way to make batteries better. The method could cut manufacturing costs as well.

The process developed at the university has improved the current-carrying capabilities of batteries by using thermal oxidation to change the electrochemical behavior of the form of carbon used in them.

Deborah D. L. Chung, Niagara Mohawk Chair of Materials Research and professor of mechanical and aerospace engineering, said using thermal oxidation to change the electrochemical behavior of carbon black improves the electron transfer rate in batteries.

She presented the findings in State College, Pa., July 13 at the Biennial Conference on Carbon. A paper on the work has been accepted for publication in an upcoming issue of the journal Carbon.

Chung explained that carbon is the most commonly used material, and carbon black the most frequently used form of carbon, in batteries.

Thermal oxidation involves heating carbon in the presence of oxygen, creating carbon-oxygen bonds that, in addition to improving electrical conduction, change carbon black's morphology, or form and structure.

While some carbons are composed of filaments or fibers, carbon black is made up of particles, like a powder, Chung noted. Ordinarily, a material such as oil, wax or another polymer is used to bind it for use in batteries.

Thermal oxidation changes carbon black's particle size and increases its macropore density, allowing the carbon black particles to "hang together" without a binder, Chung said. And since the types of binders used "tend to be a material that degrades in a chemical environment like batteries," she said, eliminating the binder will not only enhance the batteries' ability to conduct current, it also will save processing costs.

While the findings are expected to be of greatest interest to battery manufacturers, Chung's work also has applications for analytical instruments used for chemical and medical analysis.

Chung conducted the research with Christine A. Frysz, a doctoral student who is director of materials research at Wilson Greatbatch Ltd.

UB anticipates commercial development of the process and is prepared to make it available for licensing.