Design of a segmented fuel cell model for the ESDLab

Abstract

This thesis is focused on the improvement of a segmented fuel cell (SFC) for the ESDLab of the University of Alberta, which had three design and operation problems. To reach the desired design, two versions of the SFC were developed. The first design (NewSFCV1) solved two of the three main problems identified in the original version of the SFC, which were the position of manifolds inside the channels, holes in two of the four current collectors, and not a good seal between copper and graphite plates. By changing the size and relocating the manifolds and copper plate´s holes, consequences like current drop, and disturbance on reactants transport were avoided. This NewSFCV1 has endplates of 120 mm long, 100 mm wide, and 12.7 mm thick. The anode and cathode plates have 90 mm long, 70 mm wide and 9.50 mm thick. Therefore, to solve the sealing problem, a second design called NewSFCV2 was developed. This design addressed the first two problems in the same way as in the NewSFCV1 and solved the sealing problem by reducing the size of the contact area between the copper plates and the graphite pieces. These components were joined through an O-ring inside the anode plate. The size of this design increased in comparison with the previous one, with endplates of 140 mm long, 90 mm wide, and 12.7 mm thick, and with anode and cathode plates 104 mm long, 70 mm wide, and 9.5 mm thick. On the other hand, the contact area was reduced from 450 mm2 of the NewSFCV1 to 24.3 mm2 , which meant a reduction of ohmic losses. The design was modeled using COMSOL and it proved that along the cell there are different local currents and that the sum of these on the GDL side are approximately the cell´s average current density. Regarding the sensor’s calibration, the results showed that the average error was ±0.125 A, which is within the accuracy range of ± 0.15 A given by the manufacturer.

Date of Award	2022
Original language	Spanish (Peru)
Supervisor	Julien Noel (Asesor)