Practical and Reliable Methanol Concentration Sensor for Direct Methanol Fuel Cells

An electrochemical methanol concentration sensor with practicality and reliability has been developed to apply for a direct methanol fuel cell (DMFC) system. The methanol concentration can be estimated simply by the original algorithm based on the Arrhenius law and diffusion limiting current, even though the complex oxidation current characteristics for the methanol concentration and temperature. The oxidation current of methanol shows linearity against the methanol concentration up to 10 wt% (15 mgPt cm−2 at anode) with quick response. The sensor also has a high durability for 6500 h in the simulated DMFC operating temperature.