Performance of a combined electrotrophic and electrogenic biofilm operated under long-term, continuous cycling.

Yates, Matthew D.; Mickol, Rebecca L.; Vignola, Amelia; Baldwin, Jeffrey W.; Glaven, Sarah M.; Tender, Leonard M.

Objectives: Evaluate electrochemically active biofilms as high energy density rechargeable microbial batteries toward providing persistent power in applications where traditional battery technology is limiting (, remote monitoring applications). Results: Here we demonstrated that an electrochemically active biofilm was able to store and release electrical charge for alternating charge/discharge cycles of up to 24 h periodicity (50% duty cycle) with no significant decrease in average current density (0.16 ± 0.04 A/m2) for over 600 days. However, operation at 24 h periodicity for > 50 days resulted in a sharp decrease in the current to nearly zero. This current crash was recoverable by decreasing the periodicity. Overall, the coulombic efficiency remained near unity within experimental error (102 ± 3%) for all of the tested cycling periods. Electrochemical characterization here suggests that electron transfer occurs through multiple routes, likely a mixture of direct and mediated mechanisms. Conclusions: These results indicate that bidirectional electrogenic/electrotrophic biofilms are capable of efficient charge storage/release over a wide range of cycling frequency and may eventually enable development of sustainable, high energy density rechargeable batteries.

CYCLING; BIOFILMS; CYCLING competitions; CHARGE exchange; SUSTAINABLE development; ENERGY density; ELECTRIC batteries

Biotechnology Letters, 2024, Vol 46, Issue 2, p213

0141-5492

Academic Journal

10.1007/s10529-023-03450-3