Dynamically adaptive control system for bioanodes in serially stacked bioelectrochemical systems.

Area of Science:

• Microbial bioelectrochemical systems (BESs)
• Electrocatalysis
• Bioenergy and Bioremediation

Background:

• Microbial bioelectrochemical systems (BESs) are promising for bioenergy, bioproduction, and bioremediation.
• Scaling up BESs in series can lead to detrimental cell reversal.
• Effective control systems are needed for stable, large-scale BES operation.

Purpose of the Study:

• To develop and demonstrate a cell balance system (CBS) for controlling serially connected BES cells.
• To prevent cell reversal and ensure stable performance in stacked BES configurations.
• To enable rapid startup and independent operation of individual BES cells within a stack.

Main Methods:

• Implemented a cell balance system (CBS) using high-frequency metal-oxide-semiconductor field-effect transistor (MOSFET) switching.
• Dynamically adapted applied potential relative to bioanode performance in the kilohertz frequency range.
• Bypassed excess current to maintain individual cell voltage below a set point.

Main Results:

• Demonstrated simultaneous and rapid startup of multiple serially connected BES cells from a single power source.
• Achieved continuous, stable, and independent performance for each stacked BES cell.
• Confirmed stable performance of BES cells and stacks even under excessive applied currents.

Conclusions:

• The developed CBS effectively controls serially connected BES cells, preventing cell reversal.
• This system ensures stable and independent operation, crucial for scaled-up BES applications.
• The CBS technology is applicable to both large-scale stacked BES and rapid startup of individual BES units.