Top | Products | Technology | Service | Profile | Terms & Conditions | Contact    TECHNOLOGY Direct Methanol Fuel Cell 　 The Direct Methanol Fuel Cell is a special case of the PEM fuel cell. DMFCs and PEMFCs have similar structures, two electrodes are separated by an electrolyte consisting of a proton-conducting polymer membrane that is impermeable to electrons. The difference between a DMFC and a PEMFC is that the DMFC uses methanol (CH3OH) as fuel, not hydrogen. At ambient pressures (1013hPa) methanol is liquid at temperatures between -97℃ and 64℃. Thus the major advantage of a DMFC is that its fuel can be handled, stored and transported similarly to conventional liquid fuels like gasoline or diesel. On the other hand, methanol is poisonous and corrosive and DMFCs have low electrical efficiencies compared to most other fuel cell types. Applications: electric motors, portable electricity supply, battery substitute. How a DMFC works The transparency shows a schematic diagram of a DMFC. The electrolyte (PEM) is shown in yellow, the electrodes on either side of it in blue (anode on the left, cathode on the right). The anode is supplied with a methanol/water mixture (red/blue/black and red/blue molecules on the left). Due to the electrode's catalytic effect hydrogen is separated from the mixture and reduced to protons (H+ -ions, yellow +), yielding free electrons (yellow -) to the anode. Both protons and electrons now travel to the cathode side but - very importantly - on different paths. While the H+- ions pass through the cell's proton-conducting membrane the electrons move through the (closed) external circuit and thereby provide the fuel cell's electric power (indicated by light bulb). At the anode the oxygen and carbon left over from the methanol react with the oxygen from the water and form carbon dioxide (CO2). At the cathode the protons that passed through the membrane and electrons from the external circuit react with the supplied oxygen (blue) to form water (red and blue). Cathode reaction : 3O2 + 12H+ + 12e- → 6H2O Anode reaction : 2CH3OH + 2H2O → 2CO2 + 12H+ + 12e- Source: h-tec GmbH　© h-tec GmbH SUB MENU Solar-Hydrogen Energy Cycle Solar Cell PEM Electrolyzer PEM Fuel Cell Fuel Cell Stack Direct Methanol Fuel Cell 　 　 　 　 　 Top | Products | Technology | Service | Profile | Terms & Conditions | Contact Terran Cell Inc. #508-1033 Marinaside Crescent Vancouver, B.C. V6Z 3A3 Canada www.terrancell.com Copyright,2009 All rights Reserved.