2004 Volume 124 Issue 6 Pages 873-878
Cross leaked methanol in the cathode of a direct methanol fuel cell is completely oxidized, however, in the cathode of a dimethyl-ether (DME) fuel cell, the cross leaked DME is not oxidized and is exhausted from the cathode. The present paper reports that active DME oxidation such as methanol oxidation does not occur on the DME cathode until both the current density and cross leaked DME concentration exceed some upper limit. There is no cross leaked DME oxidation on a cathode under normal operating conditions, in which the current density is less than 0.2A/cm2, and the DME concentration is less than 1%. The cathode potential of the direct DME fuel cell does not decrease without active DME oxidation.