Speaker
Description
Sustainable energy systems in closed environments require innovative, low-emission solutions. This research focuses on a bioelectrochemical fuel cell based on a symbiotic culture of bacteria and yeast (SCOBY, kombucha). A key strength of the study is the rigorous evaluation of the system against a control (the natural electrochemical activity of kombucha), aligning with recent research on space biofuel cells [1]. This enabled a reliable assessment of how introduced electrode materials impact overall cell performance.
The experiment (20 °C) used a zinc anode and cathodes of varying morphologies: flat graphite and a 3D nickel sponge. Measurements in insulating environments yielded near-zero current. Results showed that working electrode material and inter-electrode distance (optimally 10 mm) are crucial for stable operation. The highest peak parameters (>24 mA at ~1.2 V) occurred with flat graphite. Conversely, polarization curve analysis under minimum resistance revealed the nickel sponge's superiority; its significantly larger active surface area generated twice the current of the graphite variant.
Findings confirm that spatial electrode modification effectively optimizes current yield in biological systems. Because zinc ions released from the anode may be toxic to microorganisms, in-depth studies on SCOBY survivability under these conditions are ongoing. Confirming their high resistance would make the tested system a highly promising component for sustainable biosensors and life-support systems. These biodegradable fuel cells offer immense potential for space missions and self-sufficient Mars habitats.
Funding: This research was supported by the TURBOGRANT ORLEN grant.
References: [1] Marczak-Grzesik, M.; Kołodziejczyk, A. M. Biofuel Cells in Space Technologies: Review with Initial Experimental Results. Preprints 2025, 2025101326.