Dynamic polarisation reveals differential steady-state stabilisation and capacitive-like behaviour in microbial fuel cells

Ledezma, Pablo; Degrenne, Nicolas; Bevilacqua, Pascal; Buret, Fran�ois; Allard, Bruno; Greenman, John; Ieropoulos, Ioannis

Abstract

In this paper we present several preliminary results produced with a purposely-designed external-resistor (R ext ) sweeping tool for microbial fuel cells (MFCs). Fast sampling rates show that MFCs exhibit differential steady-state stabilisation behaviours depending on R ext , with consequences for time constant (t c ) selection. At high R ext (35kΩ), it is demonstrated that a t c ≥10 min avoids underestimation not overestimation, whilst at low R ext (100Ω) 5min are sufficient, suggesting that sweeps with variable t c are possible. However, within the maximum power transfer range (2.5kΩ), steady-states are only observed at 20min t c but with a smaller confidence interval, questioning whether the polarisation technique is suitable to estimate maximum power transfer. Finally, a strategy towards the exploitation of a capacitive-like behaviour in MFCs is proposed, tapping into ≥10min periods with up to 50% higher current and energy transfer that could prove important for MFC-powered applications. © 2013 Elsevier Ltd.

• Journal Article Type: Article
• Acceptance Date: Oct 25, 2013
• Online Publication Date: Dec 1, 2013
• Publication Date: Jan 1, 2014
• Journal: Sustainable Energy Technologies and Assessments
• Print ISSN: 2213-1388
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 5
• Pages: 1-6
• DOI: https://doi.org/10.1016/j.seta.2013.10.008
• Keywords: microbial fuel cells, external resistors, polarisation curve, time constant, steady-states
• Public URL: https://uwe-repository.worktribe.com/output/825335
• Publisher URL: http://dx.doi.org/10.1016/j.seta.2013.10.008