Current Research Trends and Breakthroughs in Stacked Microbial Fuel Cells: Advanced Materials Development, Power Management Systems, and Techno-Economic Analysis

Stacked microbial fuel cells (MFC) have become a viable solution to circumvent the low voltage and power constraints of single-cell systems and allow the simultaneous treatment of wastewater and generation of bioelectricity. Nonetheless, the massive implementation is limited by stack instability, reversed voltage, distribution of internal resistance, and poor energy-gathering efficiency. This review offers a combined engineering insight into stacked MFC systems, with a focus on stack configurations (series, parallel, and hybrid), advanced electrode and membrane materials, voltage reversal phenomenon, and the critical role of the power management system and maximum power point tracking in stabilizing and enhancing the energy output. Moreover, the techno-economic evaluation and life-cycle analysis are also reviewed with a critical look at the scalability, sustainability of the environment, and cost-effectiveness of the system under the actual wastewater conditions. This review provides strategic insights into developing stacked MFC beyond the laboratory level models of the architectural realm to the actual wastewater treatment apparatus by integrating power electronics, economical structures, and architectural design.