A Power Management System for Multianode Benthic Microbial Fuel Cells

Benthic microbial fuel cells (BMFCs) are important energy-harvesting devices for underwater sensors and electronic devices. However, it is a challenging problem to ensure the robustness of BMFCs in harsh ocean environment. In particular, the anode buried in sediment is subject to burrowing organisms tunneling, which breaks the anaerobic condition, and the electrons generated by the anode will be consumed locally. This eliminates the difference in electric potential between the anode and the cathode. The system then becomes short-circuited and ceases to function. This is a serious problem in the underwater environment due to the likelihood of bioturbation. Using a multianode BMFC can effectively address this problem due to the distributed structure of multiple anodes. This, however, requires a new power management system (PMS) to automatically detect and remove the effect of impaired anodes. This paper presents a new PMS for multianode BMFCs. The proposed PMS automatically disconnects the impaired anodes from the rest of the system for bioturbation resilience and better efficiency. The proposed PMS is self-starting, i.e., no need of extra power sources other than the BMFC. The PMS has been tested through a prototype BFMC. Experimental results demonstrate the effectiveness of this design for multianode BMFCs.