Examination of the Optimal Separator Shape by PEFC Reaction and Flow Analysis

To improve the performance and safety of a polymer electrolyte fuel cell (PEFC), five kinds of separators (parallel, two serpentine and two semi-serpentine) were evaluated from the viewpoint of state of gas flow, uniformity of current density and temperature, reduction of pressure loss, and exhaustibility of stay water by using the PEFC reaction and flow analysis model proposed by authors. In the case of the parallel separator, flow rate and current density distributions were not uniform, and exhaustibility of the stay water was low. In the case of the serpentine separators, the pressure drop was large. On the other hand, the semi-serpentine separators, which combine parallel and serpentine separators, showed the most uniform temperature distribution and were thus concluded to be the best type of those examined in the present study.