title: Capacitive bioanodes enable renewable energy storage in microbial fuel cells.
abstract: We developed an integrated system for storage of renewable electricity in a microbial fuel cell (MFC). The system contained a capacitive electrode that was inserted into the anodic compartment of an MFC to form a capacitive bioanode. This capacitive bioanode was compared with a noncapacitive bioanode on the basis of performance and storage capacity. The performance and storage capacity were investigated during polarization curves and charge-discharge experiments. During polarization curves the capacitive electrode reached a maximum current density of 1.02 ± 0.04 A/m(2), whereas the noncapacitive electrode reached a current density output of only 0.79 ± 0.03 A/m(2). During the charge-discharge experiment with 5 min of charging and 20 min of discharging, the capacitive electrode was able to store a total of 22,831 C/m(2), whereas the noncapacitive electrode was only able to store 12,195 C/m(2). Regarding the charge recovery of each electrode, the capacitive electrode was able to recover 52.9% more charge during each charge-discharge experiment compared with the noncapacitive electrode. The capacitive electrode outperformed the noncapacitive electrode throughout each charge-discharge experiment. With a capacitive electrode it is possible to use the MFC simultaneously for production and storage of renewable electricity.
authors.affiliation: Sub-Department of Environmental Technology, Wageningen University, Bornse Weilanden 9, PO Box 17, 6708 WG Wageningen, The Netherlands. Alexandra.Deeke@wetsus.nl
authors.forename: Alexandra
authors.initials: A
authors.lastname: Deeke
authors.forename: Tom H J A
authors.initials: TH
authors.lastname: Sleutels
authors.forename: Hubertus V M
authors.initials: HV
authors.lastname: Hamelers
authors.forename: Cees J N
authors.initials: CJ
authors.lastname: Buisman
mesh_terms: D001674:Bioelectric Energy Sources; D018441:Biofilms; D004566:Electrodes; D016062:Porosity; D059205:Renewable Energy