Supercapacitive paper based microbial fuel cell: High current/power production within a low cost design

Area of Science:

• Electrochemistry
• Renewable Energy Systems
• Biotechnology

Background:

• Microbial fuel cells (MFCs) offer a sustainable approach to energy generation.
• Investigating MFCs in a supercapacitive configuration enhances their energy storage potential.
• Paper separators and liquid-containing elements are key components in MFC design.

Purpose of the Study:

• To evaluate the performance of MFCs in a supercapacitive mode.
• To assess the discharge and self-recharge characteristics of MFCs.
• To determine the durability and stability of MFCs under continuous operation.

Main Methods:

• MFCs with paper separators and liquid elements were configured in a supercapacitive setup.
• Plain wrapped carbon veil anodes and conductive latex cathodes were utilized.
• Galvanostatic discharge and self-recharge cycles were performed at varying current pulses (1–7 mA).

Main Results:

• MFCs exhibited an equivalent series resistance of 41.2 ± 3.5 Ω, primarily due to the cathode.
• A maximum power output of 1.380 ± 0.083 mW (0.092 ± 0.006 mW/mL) was achieved.
• Durability tests over 24 hours (1000 cycles) showed a performance decline, potentially linked to anode liquid evaporation, while resistance and capacitance remained stable.

Conclusions:

• MFCs can function in a supercapacitive mode with self-recharging capabilities.
• Cathode resistance significantly impacts MFC performance in this configuration.
• Anode liquid management is crucial for maintaining long-term MFC stability and performance.