Design and operation of an electrochemical methanol concentration sensor for direct methanol fuel cell systems

The design and operation of a methanol concentration sensor suitable for us e with direct methanol fuel cells is described. The sensing principle is ba sed on the measurement of concentration-dependent oxidation currents for th e electro-oxidation of methanol in a polymer electrolyte membrane cell at a platinum-ruthenium electrode. The device construction and properties are d escribed. The sensor was integrated with an automatic fuel feed system, and was operated for several tens of hours. The results demonstrate that the s ensor is robust and sensitive enough to meet the demands of concentration s ensing and control in direct methanol fuel cell systems. (C) 2000 The Elect rochemical Society. S1099-0062(99)09-073. All rights reserved.