DISTINCT PERFORMANCE EVALUATION OF A DIRECT METHANOL SPE FUEL-CELL - A NEW METHOD USING A DYNAMIC HYDROGEN J-REFERENCE ELECTRODE

A stable reference electrode to be operated in a proton-exchange membr ane direct methanol fuel cell (PEMDMFC) was strongly desired but is st ill lacking. Conventional reference electrodes known from aqueous syst ems are difficult to mount and to connect to the membrane electrolyte, and they introduce Donnan potential into the system. It is shown in t his study that a dynamic hydrogen electrode roughly maintains the ther modynamic hydrogen potential when operated at low cathodic current den sity sufficient to uphold the saturation with hydrogen of the electrod e. Such a polarised auxiliary electrode allows the determination of a single electrode potential versus current density curves directly in t he fuel cell, even during operation of the DMFC. A distinct determinat ion of single electrode performance and fuel crossover is now possible .