Engineering news
A team of University of Toronto chemists has created a battery that stores energy in a vitamin-derived cathode, paving the way for cheaper consumer electronics that are more environmentally friendly.
The battery is similar to many commercially-available high-energy lithium-ion batteries but it uses flavin from vitamin B2 as the cathode: the part of the battery which stores the electricity that is released when connected to a device.
Researchers said that B2's ability to be reduced and oxidised makes its well-suited for a lithium ion battery.
"B2 can accept up to two electrons at a time," said Dwight Seferos, associate professor in the University of Toronto’s Department of Chemistry. "This makes it easy to take multiple charges and have a high capacity compared to a lot of other available molecules."
Modern batteries contain three basic parts: a positive terminal - the metal part that touches devices to power them - connected to a cathode inside the battery, which cases a negative terminal. This is connected to an anode inside the battery casing an electrolyte solution, in which ions can travel between the cathode and anode electrodes.
While bio-derived battery parts have been created previously, this is the first one that uses bio-derived polymers - long-chain molecules - for one of the electrodes, essentially allowing battery energy to be stored in a vitamin-created plastic, instead of costlier, harder to process, and more environmentally-harmful metals such as cobalt.
"It's a pretty safe, natural compound," Seferos said. "If you wanted to, you could actually eat the source material it comes from."
Seferos, doctoral student Tyler Schon and colleagues discovered the material while testing a variety of long-chain polymers - specifically pendant group polymers: the molecules attached to a 'backbone' chain of a long molecule.
The team created the material from vitamin B2 that originates in genetically-modified fungi using a semi-synthetic process to prepare the polymer by linking two flavin units to a long-chain molecule backbone.
This allows for a green battery with high capacity and high voltage - something the researchers said is increasingly important as the 'Internet of Things' continues to link us together more and more through our battery-powered portable devices.
"It's been a lot of trial-and-error," said Schon. "Now we're looking to design new variants that can be recharged again and again."
While the current prototype is on the scale of a hearing aid battery, the team hopes their breakthrough could lay the groundwork for powerful, thin, flexible, and even transparent, metal-free batteries that could support the next wave of consumer electronics.