Bacteria-powered biobattery with a shelf life of 100 years
(Nanowerk News) Last fall, Professor Seokheun “Sean” Choi and his Laboratory of Bioelectronics and Microsystems published their research on digestible biobattery activated by the Ph factor of the human gut.
Now, he and PhD student Maryam Rezaie have taken what they learned and put it into new ideas for use outside the body.
A new study in the journal Small (“Moisture Activated Germination of Heat Activated Bacillus Endospores for Fast and Practical Bioelectric Generation: Towards Portable, Storeable Bacteria-Powered Biobatteries”), shared the results of using similar spore-forming bacteria to pre-digestible versions to build devices that could potentially still work after 100 years.
“The overall goal is to develop a microbial fuel cell that can be stored for a relatively long time without degrading the biocatalytic activity and can also be activated quickly by absorbing moisture from the air,” said Choi, a faculty member in the Department of Electricity. and Computer Engineering at the Thomas J. Watson College of Engineering and Applied Science.
“We wanted to make these biobatteries for portable, storable, and on-demand power generation capabilities,” said Choi. “The problem is, how do we provide for long-term storage of bacteria until use? And if that’s possible, then how do you provide on-demand battery activation for quick and easy power generation? And how do you increase its power?
The dime-sized fuel cell is covered with Kapton tape, a material that can withstand temperatures from -500 to 750 degrees Fahrenheit. When the tape is removed and moisture gets in, the bacteria mix with chemical germs which encourage the microbe to produce spores. The energy from this reaction is enough to power an LED, a digital thermometer, or a small clock.
Heat activation of the bacterial spores cuts the time to full power from 1 hour to 20 minutes, and increasing the humidity results in a higher electrical output. After a week of storage at room temperature, there was only a 2% decrease in power generation.
The study was funded by the Office of Naval Research, and it’s easy to envision military applications for a resource that could be used on the battlefield or in remote locations. However, there would be many civilian uses for such a fuel cell as well.
While these were all good results, Choi knew that fuel cells like these needed to fire up faster and produce more voltage to be a viable alternative to traditional batteries.
“I think it’s a good start,” he said. “Hopefully, we can make a commercial product using these ideas.”
