Locally Resolved Measurements in a Segmented HTPEM Fuel Cell with Straight Flow‐Fields

Abstract

Significant advances have been reported in building and testing of high‐temperature polymer electrolyte membrane (HTPEM) fuel cells and stacks during recent years. Quantity distribution measurement techniques (e.g. current density, temperature and electrochemical impedance spectroscopy (EIS)) using segmented cells are commonly used to characterise low‐temperature PEM (LTPEM) fuel cells. Performing these measurements at higher temperatures is more difficult and a relatively new process. For this study, a fully operational segmented HTPEM fuel cell using a straight flow‐field configuration was designed, constructed and tested. The cathode side bipolar half‐plate consisted of 36 exchangeable segments, whereas, the anode side bipolar half‐plate was not segmented. The cell was operated at various operating temperatures with various anode gas compositions and air (no backpressure). In addition to the experimental results, a simple computational fluid dynamics model based on COMSOL Multiphysics® 3.5a was used to support the observed behaviour during segmented measurements. The computational domain consisted of the cathode side gas channels and the porous media. All of the boundary conditions and gas properties were defined in a manner similar to the experimental investigations. Some of the theoretical results were compared to the experimental results and conclusions were drawn.

Challenges and opportunities for characterisation of high-temperature polymer electrolyte membrane fuel cells: a review

“…327 One application of current distribution mapping used in HT-PEMFC research is the investigation of ow eld geometry effects. 154,330 Fig. 14 and 15 show how this mapping technique has been used to investigate the impact on current density distribution of four different ow eld patterns.…”

Evaluating Current Distribution and Influence of Defect Sites for Graphitic Compound Bipolar Plate Materials

“…To the best of our knowledge, there are no reports on experimental evaluation of in‐plane current distribution in graphitic materials. Although there is research on cell characteristics (current density and temperature) using segmented cell technology , none of the studies, to our knowledge, specifically look at the influence of the conductivities of the BPP material. Instead, these studies use membrane electrode assemblies (MEAs) and investigate conditions causing inhomogeneous current generation but do not measure its propagation or compensation.…”