A Glowing Solution: Fluorescent Dye Can Fuel Batteries

Scientists from the University at Buffalo have discovered the next breakthrough in energy storage technology: glow-in-the-dark dye. BODIPY, short for boron-dipyrromethene, is a fluorescent dye that was discovered to be an ideal candidate for storing energy in rechargeable, liquid-based batteries that could potentially power cars and homes.

BODIPY glows brightly under a black light and has unusual chemical properties that enable it to excel at two key tasks: storing electrons and participating in electron transfer. In experiments, a BODIPY-based test battery operated efficiently and ran well after researchers drained and recharged it 100 times. The research was published in ChemSusChem, an academic journal devoted to the intersection of chemistry and sustainability.

"As the world becomes more reliant on alternative energy sources, one of the huge questions we have is, 'How do we store energy?' What happens when the sun goes down at night, or when the wind stops?" said Timothy Cook, PhD, an assistant professor of chemistry at the University at Buffalo College of Arts and Sciences and the lead researcher of the study. "All these energy sources are intermittent, so we need batteries that can store enough energy to power the average house."

Lithium-ion batteries, a popular battery type, are risky in that they can catch fire if they break open, according to Cook. The dye-based batteries would not have this problem; if they ruptured, they would simply leak. BODIPY can be used for a liquid-based battery or a "redox flow battery" and can be easily enlarged to store more energy, a feat that is challenging for other existing battery types.

Redox flow batteries consist of two tanks of fluids separated by various barriers.

When the battery is being used, electrons are harvested from one tank and moved to the other, generating an electric current. In theory, this could power devices as small as a flashlight or as big as a house. To recharge the battery, solar, wind or other energy sources could be used to force the electrons back into the original tank, where they would be available to do their job again.

"The library of molecules used in redox flow batteries is currently small but is expected to grow significantly in coming years," Cook stated. "Our research identifies BODIPY dye as a promising candidate."