title: Comprehensive characterization and understanding of micro-fuel cells operating at high methanol concentrations.
abstract: We report on the analysis of the performance of each electrode of an air-breathing passive micro-direct methanol fuel cell (µDMFC) during polarization, stabilization and discharge, with CH3OH (2-20 M). A reference electrode with a microcapillary was used for separately measuring the anode the cathode potential. Information about the open circuit potential (OCP), the voltage and the mass transport related phenomena are available. Using 2 M CH3OH, the anode showed mass transport problems. With 4 and 6 M CH3OH both electrodes experience this situation, whereas with 10 and 20 M CH3OH the issue is attributed to the cathode. The stabilization and fuel consumption time depends mainly on the cathode performance, which is very sensitive to fuel crossover. The exposure to 20 M CH3OH produced a loss in performance of more than 75% of the highest power density (16.3 mW·cm(-2)).
authors.affiliation: IC2MP, UMR-CNRS 7285, University of Poitiers, 4 rue Michel Brunet, 86022 Poitiers, France.
authors.forename: Aldo S
authors.initials: AS
authors.lastname: Gago
authors.affiliation: Instituto de Microelectrónica de Barcelona, IMB-CNM (CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain.
authors.forename: Juan-Pablo
authors.initials: JP
authors.lastname: Esquivel
authors.affiliation: Instituto de Microelectrónica de Barcelona, IMB-CNM (CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain.
authors.forename: Neus
authors.initials: N
authors.lastname: Sabaté
authors.affiliation: Instituto de Microelectrónica de Barcelona, IMB-CNM (CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Santander
authors.affiliation: IC2MP, UMR-CNRS 7285, University of Poitiers, 4 rue Michel Brunet, 86022 Poitiers, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Alonso-Vante
keywords: fuel crossover; methanol; micro-fabrication; passive direct methanol fuel cell (DMFC); reversible hydrogen electrode (RHE)