Picture this: a battery you can feed instead of charging. This is exactly what the research team at Empa had in mind when working on their innovation: a biodegradable battery made of 3D-printed fungi. According to the team, this living device with a capacity to power sensors for agriculture or research in remote regions, digests itself from the inside once its job is done.
Fungi, a kingdom of life closely related to animals, have fascinated scientists for decades. From edible mushrooms to disease-causing pathogens, fungi are amazingly diverse. Empa researchers have discovered an unexpected ability of fungi: generating electricity. Their research is a part of a three-year project supported by the Gebert Rüf Stiftung’s Microbials funding program, in which the scientists from Empa’s Cellulose and Wood Materials laboratory developed a fully functional fungal battery. Although the living cells do not generate much electricity, they can power a temperature sensor for several days, making them useful in agriculture or environmental research.
The fungal battery is technically a microbial fuel cell that captures energy from the metabolism of fungi. For the first time, Empa combined two fungi species to create a functioning fuel cell. One fungus, a yeast, releases electrons, while a white rot fungus captures and conducts them. The 3D-printed structure allows the fungi to thrive and easily access nutrients, including cellulose.
Working with the living materials brings a number of challenges, but the research team seems unstoppable. The project combines multiple disciplines, including microbiology, materials science and electrical engineering. This interdisciplinary approach often involves microbiologists learning electrochemistry techniques, and even adapting them to 3D-printing inks. With such determination, the team will likely soon enhance the battery’s power and longevity, while further exploring the potential of fungi in materials science.
