3D-printed fungi batteries: A path to a biodegradable tech future?

By Beyza Binnur Donmez

GENEVA (AA) — As electronic waste increasingly burdens the world, where discarded batteries leak toxic chemicals into the soil and waterways, a team of Swiss researchers is turning to an unlikely ally in the quest for sustainability: fungi.

In what could pave the way for eco-friendly energy solutions for low-power electronics, researchers at the Swiss Federal Laboratories for Materials Science and Technology (Empa) have created a “fungal bio-battery.”

Gustav Nystrom, head of the cellulose and wood materials lab at Empa, and his team have been working on this microbial fuel cell for three years, focusing on the use of sustainable and biodegradable materials.

Their goal, Nystrom told Anadolu, is to rethink ways to fuel low-power electronics, particularly those designed for environmental monitoring or scenarios where devices might not be fully recycled.

“The general inspiration for this is that we think that there is a need to rethink some of the power sources that might be needed for low-power electronics and to try to create devices which are non-critical if they should be left out in the environment, either because of the application requires this, such as in environmental monitoring, or if it’s not fully recycled and ends up in the wrong place in the waste treatment system,” he said.

“Mitigating issues with electronic waste is one big motivator for us, and the other is to think about new ways to work with sustainable materials, also for electronic devices,” he added.

Unlike traditional batteries, the fungal bio-battery relies on living microorganisms. According to Nystrom, when fungi digest organic materials, they generate energy in the form of electrons, which are harvested to produce electricity.

- ‘Complex’ development process

Nystrom emphasized that the innovation required overcoming significant challenges.

He explained that the fungi must remain alive in a dense gel system suitable for 3D printing, withstand the printing process, and thrive in an environment engineered to conduct electricity using carbon particles.

The process was “complex,” and creating a 3D-printable living battery is “actually a big challenge and not trivial to succeed with,” Nystrom said.

“I think all of these, let's say, sustainable energy storage devices that we have developed in my lab are not to think about as a replacement for traditional batteries. It's more to think about how we can use energy from such a device, and in the next step, incorporate it with the sensing system,” he said.

The team envisions 3D printing the entire bio-battery device in the future, which would allow for customizable designs tailored to specific applications.

“Now, we print small volumes, small devices,” he said. “You can think about larger printing setups, printing in parallel, and all of these things, but we’re still in the lab setting.”

Despite being in its experimental phase, the fungal bio-battery shows promise for various applications, particularly in environmental and agricultural sensing, wearable technology, and disposable diagnostic kits. These often require low-power energy sources that can be safely left in the environment.

- Sustainable approach

A key focus of the project was the use of biodegradable materials, a decision driven by the team’s commitment to minimizing electronic waste, Nystrom said.

“This is one of the things that we tried, from the very beginning with all of this work, just to select or source materials that are biodegradable,” he explained. “Everything that goes into this device … can be degraded” in the environment.

He believes this approach contributes to addressing the growing problem of electronic waste.

“It’s also a choice that makes it more challenging to work in this area,” he said. “We wanted to see how far we can still get good performance using only green, eco-friendly, or biodegradable materials.”

Regarding commercial viability, Nystrom noted that while research is ongoing, the scalability and potential cost-effectiveness of bio-batteries offer hope for future commercialization.

“I think it’s a promising technology, but the commercialization aspect — we haven’t evaluated that closely yet because we were focusing on the performance of the devices,” he said.

“We are definitely using scalable materials, and materials available on a large scale should not be that costly,” added Nystrom, while acknowledging that it would be difficult to foresee the exact method of production and how many could be manufactured.

“I think it has the potential to be very cost-efficient, but it’s too early to make any firm statement,” he added.