Manufacture, Modeling And Control Of Tubular Direct Methanol Fuel Cell

Direct Methanol Fuel Cell (DMFC) converts the chemical energy of methanol and the oxygen into the electrical energy directly, without reforming process. DMFC can be used for portable power sources specially, because the fuel possesses the characteristics such as higher power density, cheapness and storage convenience. The DMFC stack was designed in plannar structure, which needs the expensive bi-polar to transfer the reactants to every fuel cell and the electrons produced by electrochemical reaction to the load. The peripheral equipments such as the tank, gas cylinders and pumps must be used for storing and transferring the reactants to sustain the DMFC system working normal, since the flow channel of the bi-polar is narrow. The use of bi-polar not only increases the stack's cost, but also involves certain difficulties to the system assembly and maintenance, for example, if one single fuel cell of the stack destroyed, the whole stack had to disassemble and assemble again. An idea of designing Tubular Direct Methanol Fuel Cell (TDMFC) was proposed to overcome the disadvantages of plannar DMFC. Used the air-brush to spray the catalyst ink on the membrane, and rolled, hot-pressed the above membrane together with the carbon cloth, the TDMFC membrane electrode assembly, a single TDMFC and a stack were manufactured by this technique. Support tubular proton exchange membrane was made by dip coating process with porous quartz tube and Nafion solution, which used to manufacture the support tubular direct methanol fuel cell finally.Modeling and numerical analysis the dynamics behaviors of TDMFC, give the simulation result of the concentration profiles of reactants and products, and the temperature profile of the whole system. Analysis the theoretic and practical efficiency of fuel cell used the thermodynamics parameters. Illustrated the relation between the DMFC's efficiency and the current density.