Firefly Receives Patent on Carbon Foam Battery

Firefly Energy of Peoria, Illinois, says the U.S. Patent and Trademark Office has issued patent number 6,979,513, titled, “Battery Including Carbon Foam Current Collectors.” The patent was awarded on December 27, 2005.

The invention is a battery comprised of an electrical current collector constructed of carbon or lightweight graphite foam. This foam exhibits a sizeable increase in surface area for chemical reactions to take place and eliminates the need for heavy lead plates found in traditional batteries. The graphite material resists corrosion and sulfation build-up, thus contributing to longer battery life and is lighter in weight than today’s lead acid batteries.

Chief Scientist Kurtis C. Kelley developed the technology while serving as senior research scientist in the advanced materials division of Caterpillar’s R&D center.

“Since Kurt, an accomplished material scientist, had never designed a battery before, his problem-solving approach was unconstrained by the conventional battery wisdom held by lead-acid battery technologists,” says Edward F. Williams, CEO and a co-founder of Firefly Energy.

The overwhelming restriction to lead-acid battery efficiency has been the lack of interface area between the active chemistry and the electrodes. The chemistry is capable of delivering approximately 170Whr/kg, yet lead-acid batteries only average around 30Whr/kg.

“By replacing corrosive heavy lead grids with graphite foam, Kurt Kelley’s invention has helped unleash the innate power of lead-acid chemistry,” Williams adds. “It’s a material that doesn’t corrode and enables the weights and sizes of lead-acid batteries to be reduced significantly.”