This newly developed battery can be activated by spit

Researchers from Binghamton University, in collaboration with their colleagues at State University of New York, developed a new Battery that can be easily activated by spit. The new paper-based bacteria powered batteries can be used as an inexpensive alternative to commercial batteries, especially resource-limited regions.

Bacteria-powered batteries

Microbial fuel cell, or also known as the biological fuel cell, is a bio-electrochemical system that generates electric current by mimicking bacterial interactions that commonly occurs in nature.

Unlike commercial batteries or other harvesting technologies, the new paper-based bacteria-powered battery is inexpensive and environment-friendly. Additionally, the long shelf-life of the paper-based bio battery makes it suitable for regions with extreme conditions.

For the new battery, the researchers built microbial fuel cells with inactive, freeze-dried exoelectrogenic cells that can be readily activated by a spit. By freeze-drying the exoelectrogenic cells, it can be stored for a long-term without degrading. The use of an oxygen-tight interface and engineered conductive paper reservoir maximized the microbial electron transfer efficiency, significantly boosting the performance of the paper-based bio battery.

A single drop of saliva can generate reliable energy to power point-of-care (POC) diagnostic biosensors.

So far, the researchers were able to generate a power density of about a few microwatts per centimeter square. However, connecting together 16 of the microbial fuel cells can generate enough current and voltage to power a light-emitting diode (LED). The researchers claim that further improvements of the new bacteria-powered battery could produce up to hundreds of milliwatts of energy.

The importance of micro-power sources

Micro-power generation through an inexpensive and readily available paper-based bacteria powered battery is very important in regions where the supply of commercial batteries is very limited.

Micro-power sources, like the new battery, can be used to power POC biosensors, which only requires about several tens of microwatt-level power for several minutes.

POC biosensors are used during the so-called “bedside testing” or POC testing. Bedside testing is defined as medical diagnostic testing at the time and place of patient care. Previously, diagnostic testing was wholly or mostly confined within the walls of a medical laboratory. However, the advent of technology made it possible for some diagnostic devices and tools to be readily used even in remote places.