Batteries made of lemons and oranges have been gracing grade school laboratories for years. In addition to fruit-based batteries, now you can make a battery using spit.
The new paper-based bacteria-powered battery can be activated with a single drop of saliva, generating enough power to power an LED light for around 20 minutes.
“The battery includes specialized bacterial cells, called exoelectrogens, which have the ability to harvest electrons externally to the outside electrode,” Seokheun Choi, co-author of the new study, tells Nexus Media. “For the long-term storage, the bacterial cells are freeze-dried until use. This battery can even be used in challenging environmental conditions like desert areas. All you need is an organic matter to rehydrate and activate the freeze-dried cells.”