Distinct performance evaluation of a direct methanol SPE fuel cell. A new method using a dynamic hydrogen reference electrode

Abstract

A stable reference electrode to be operated in a proton-exchange membrane direct methanol fuel cell (PEMDMFC) was strongly desired but is still lacking. Conventional reference electrodes known from aqueous systems are difficult to mount and to connect to the membrane electrolyte, and they introduce Donnan potentials into the system. It is shown in this study that a dynamic hydrogen electrode roughly maintains the thermodynamic hydrogen potential when operated at low cathodic current density sufficient to uphold the saturation with hydrogen of the electrode. Such a polarised auxiliary electrode allows the determination of a single electrode potential versus current density curves directly in the fuel cell, even during operation of the DMFC. A distinct determination of single electrode performance and fuel crossover is now possible.