Experimental Investigation of a Novel Cathode Matrix Flow Field in Proton Exchange Membrane Fuel Cell
Abstract
The flow field design is critical for the proton exchange membrane fuel cell optimization, and a novel cathode matrix flow field is experimentally investigated in this work. The results show that the cell with the matrix flow field has better performance than that with the conventional parallel and serpentine flow fields, especially at high relative humidity (75% higher current density at 0.6V and 100% relative humidity). Furthermore, the pressure drop of the matrix flow field is much less than that of the serpentine flow field. But the matrix flow field shows worse liquid discharge capacity than the serpentine flow field. Decreasing the single block area in the investigated range will increase the ohmic loss but greatly decrease the activation loss that highlights the advantages of the matrix flow field. For visualization of water discharge, the smaller single block leads to more water accumulation at the corners of the flow field. Therefore, sub-regions and compulsive gas distribution should be considered if the matrix flow field is applied in large-scale fuel cells. The matrix flow field with the compact block arrangement shows reduced ohmic and activation losses by the large conductive area and enhanced air guidance effect in the investigated range.