Recovery of electrical energy produced by microbial fuel cells associated in series

Microbial Fuel Cells (MFCs) produce electricity from the degradation of organic matter by bacteria. MFCs are considered as low voltage, low power micro-generators. In order to recover the electrical energy produced in order to be able to supply independent sensors, architectures implementing several cells are preferred. The association of a large number of individual MFCs offers very interesting prospects, in particular at the level of the production of electric power. This makes it possible to reach acceptable voltage levels at the output and makes it possible to pool the electrical powers of each cell. The serial association of a large number of MFCs is a challenge because of hydraulic couplings (when MFCs share the same substrate) and because of non-uniformities between generators which lead to inefficient association. Voltage balancing circuits can be a solution to compensate for these inhomogeneities. They can improve the efficiency of the association and prevent the phenomenon of voltage reversal. This article details several solutions based on the use of balancing circuits, allowing to optimize the serial association of several MFCs