Researchers have presented an innovative concept for environmentally friendly batteries that generate electrical energy with the help of fungi. The system combines 3D printing and microbial fuel cell (MFC) design to power sensors for several days. The basis of this technology is a fully biodegradable structure made of cellulose and hydrogel-based inks containing living microorganisms.
The so-called “Fungal Battery” consists of two chambers: an anode system with yeast and a cathode that uses white wood rot fungi (white-rot fungi). Both organisms perform specific tasks in the energy conversion process. The yeast (Saccharomyces cerevisiae) oxidizes sugar, generating electrons that flow through the anode system. The wood rot fungus (Trametes pubescens) in the cathode uses laccase enzymes to reduce oxygen, which completes the electrochemistry.
A central element is the 3D printing process. In this process, the electrodes are printed directly into the desired geometry using special inks, which enables higher porosity and better diffusion of electrolytes. This method offers greater flexibility in the design of fuel cells for various applications. In addition, the use of cellulose as the main material facilitates the integration of bio-components and makes the entire system biodegradable.
Initial tests show that the bio-battery can reach a voltage of 400 to 500 millivolts, sufficient to power low-energy devices such as temperature sensors. A prototype made of beeswax and a cellulose membrane was also successfully tested for its biodegradability. Within three weeks, the battery completely disintegrated in a compost simulation system.
The researchers see great potential for sustainable applications in this development. In particular, such batteries could be used in environmental monitoring and agriculture to operate autonomous sensors. The batteries could be further optimized by integrating waste from food or agriculture as an energy source.
The complete scientific paper entitled “3D Printed Cellulose-Based Fungal Battery” can be read here.