Effect of Spiral Flow Field Design on Performance and Durability of HT-PEFCs

Abstract

The geometries of flow fields have a strong impact on gas distribution in fuel cells. In the present work, a series of customized spiral flow fields were applied to high-temperature polymer electrolyte fuel cells. Pressure tests revealed that a flow crossover occurred in the spiral flow field under consideration, which was caused by the pressure difference between two adjacent channels. Electrochemical characterization indicated that the modified gas distribution compensated the O2 depletion along the channel and improved the supplement of O2 in the electrode, as well as the proton conductivity of the electrolyte. The best performances were obtained with a spiral flow field using a channel depth of 1.0 mm. This cell was operated for up to 1000 h under a constant load. The spiral cell exhibited a higher voltage and five times lower degradation rate than a serpentine cell which was analyzed for comparison. This effect was mainly attributed to the modified gas distribution, including the water vapor, which was verified by the computational fluid dynamics analysis.

Influence of the Interaction Between Phosphoric Acid and Catalyst Layers on the Properties of HT‐PEFCs

“…The MEAs were assembled inside the cell without a preceding hot-pressing step. Graphitic flow field plates with machined threefold serpentine structure were used [15,16]. The stainless steel end plates were heated to adjust the operating temperature.…”

Application of metal foams to high temperature PEM fuel cells

“…The increase in catalyst particle size was observed to occur during two longterm experiments. Liu et al [23] showed that flow channel design greatly affects the performance and stability of HTPEMFCs.…”

Flow simulation and analysis of high-power flow batteries

“…A second series of studies [19,20,21,22,23] used CFD techniques to simulate full 3D PEMFCs. These studies examined polarization curves, pressure drops, and a number of cell design parameters.…”