- Biodegradable battery invented by scientists in Switzerland
- Mushrooms, which is the building block of mushrooms, is the basic material used
- Mushroom-powered battery generates enough electricity to power sensors
Mushrooms have fascinated scientists for decades – centuries, probably. There are about 200,000 known species on the planet, they are more closely related to animals than plants, the largest organism in the world is a fungus, and some can glow in the dark. If you watched or played The last of us, You’ll know that the Cordyceps parasitic fungus infects its host by colonizing and consuming its body (granted, in the real world it takes over insects and won’t invade humans anytime soon).
Thanks to a three-year project supported by the microbial funding program of Gebert Rüf Stiftung, researchers from EMPA (Swiss Federal Laboratories for Materials Science and Technology) have found a new use for fungi – as they have developed a 3D printed biodegradable fuel cell This requires power rather than charging.
Although the fungal battery (technically it’s a microbial fuel cell rather than a battery itself) produces only modest amounts of electricity, EMPA says it can sustain devices such as temperature sensors for several days.
3D printed battery
Microbial fuel cells work by harnessing the metabolism of living organisms to produce electricity. In the past this has been done with bacteria. EMPA’s breakthrough combines two species of fungi: a yeast fungus on the anode side, which releases electrons, and a white rot fungus on the cathode side, which produces an enzyme that captures and conducts these electrons.
“For the first time, we have combined two types of fungi to create a functional fuel cell,” explains EMPA researcher Carolina Reyes.
Rather than adding fungi to a pre-assembled battery, the researchers integrated fungal cells into the structure of the 3D printed battery itself. The electrodes have been carefully designed to provide nutrients to the fungi while remaining biodegradable and conductive.
Traditional battery disposal poses environmental challenges, as many contain toxic materials that can contaminate soil and water if not properly managed. EMPA’s living batteries don’t have this problem because they are cleverly self-digesting – consuming the cellulose-based ink the fungal cells are embedded in – once their purpose is served.
For the main nutrient source, researchers add simple sugars to the battery cells. “You can store fungal batteries in a dried state and activate them on site by simply adding water and nutrients,” says Reyes.
Although it is a promising idea, the project faces challenges due to the complexity of working with living materials, the blending of microbiology, materials science and electrical engineering. EMPA plans to experiment with different forms of mushrooms in the future in hopes of finding combinations that will make the fungal battery more powerful and longer lasting.
