Fast design and manufactured on complex flow channel by rapid prototyping for air-breathing polymer electrolyte membrane fuel cells

The miniature and air-breathing fuel cell has become the globally major design concepts of fuel cell development recently. In this paper, the authors used 3-D drafting software for fast design and utilize rapid prototyping (RP) technology to accelerate the prototype development of new stack designs and optimize the assembly method. A fast design and convenient manufacture tool, i.e., rapid prototyping, has been first successfully applied to the fabrication of the complicated flow channels of both DMFC and PEMFC in this paper. The honeycomb shape methanol reservoir and honeycomb cathode structure design of DMFC and a complex flow distributor design of mono-polar PEMFC stack, which are almost impossibly manufactured by traditional CNC manufacturing, is fabricated by rapid prototyping technology and illustrated for the extraordinary advantages of RP technology. This paper shows that the fast design and manufacture characteristics are more important for the feasibility study of a complicated structure and any new design ideas. Although the performance of air-breathing pseudo-polar DMFC is only 2.16 mW/cm² in peak power density by using 50% of hydrophobic carbon paper; this poor performance is resort to the MEA of DMFC is not well prepared. The other example of the power density of 188 mW/cm² (at 0.425 V) in parallel-connection and 123mW/cm² (at 4.25V) in serial-connection for the air-breathing mono-polar PEMFC stack are achieved. The performance of the stack is close to the state-of-the-art comparing to recently published literatures [6-9 ].