Analysis of polarization methods for elimination of power overshoot in microbial fuel cells

Valerie J. Watson, Bruce Ernest Logan

Research output: Contribution to journalArticle

119 Citations (Scopus)

Abstract

Polarization curves from microbial fuel cells (MFCs) often show an unexpectedly large drop in voltage with increased current densities, leading to a phenomenon in the power density curve referred to as "power overshoot". Linear sweep voltammetry (LSV, 1 mV s- 1) and variable external resistances (at fixed intervals of 20 min) over a single fed-batch cycle in an MFC both resulted in power overshoot in power density curves due to anode potentials. Increasing the anode enrichment time from 30 days to 100 days did not eliminate overshoot, suggesting that insufficient enrichment of the anode biofilm was not the primary cause. Running the reactor at a fixed resistance for a full fed-batch cycle (~ 1 to 2 days), however, completely eliminated the overshoot in the power density curve. These results show that long times at a fixed resistance are needed to stabilize current generation by bacteria in MFCs, and that even relatively slow LSV scan rates and long times between switching circuit loads during a fed-batch cycle may produce inaccurate polarization and power density results for these biological systems.

Original languageEnglish (US)
Pages (from-to)54-56
Number of pages3
JournalElectrochemistry Communications
Volume13
Issue number1
DOIs
StatePublished - Jan 1 2011

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Microbial fuel cells
Anodes
Polarization
Switching circuits
Biofilms
Biological systems
Voltammetry
Bacteria
Current density
Electric potential

All Science Journal Classification (ASJC) codes

  • Electrochemistry

Cite this

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Analysis of polarization methods for elimination of power overshoot in microbial fuel cells. / Watson, Valerie J.; Logan, Bruce Ernest.

In: Electrochemistry Communications, Vol. 13, No. 1, 01.01.2011, p. 54-56.

Research output: Contribution to journalArticle

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