Water Transport and PEFC Performance with Different Interface Structure between Micro-Porous Layer and Catalyst Layer

Yusuke Aoyama,Takemi Chikahisa,Toshihiro Tanuma,Kengo Suzuki,Yutaka Tabe

doi:10.1149/2.0451605jes

Yusuke Aoyama, Takemi Chikahisa + Show 3 more

Open Access

https://doi.org/10.1149/2.0451605jes

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Abstract

For interfaces between micro-porous layers (MPL) and catalyst layers (CL) made by the gas diffusion electrode (GDE) method, a seamless interface without gaps, shows better performance than that of cells with an interface made by the decal transfer method. With the decal transfer method, the MPL is simply hot-pressed to the CL-membrane assembly. This study investigates the effect of interface structure on cell performance and water transport in the MPL. Water distribution in cross sections of multiple layers were observed by a freezing method, where the cell is cooled below freezing temperature in short time and the water was observed in ice form by Cryo-SEM. The results show that a membrane electrode assembly (MEA) using the GDE method improves cell performance at high current densities. Direct observations by the freezing method and cryo-SEM show that there is no water accumulation at the MPL/CL interface made by the GDE method, while water accumulates at the interface made by the decal method. Other observations show that the water amount inside the MPL increases similarly in the two types of MEA when lowering the temperature, and the difference between the two types of MEA was only the water amount in the interface.

Highlights

Yusuke Aoyama,a,z Kengo Suzuki,a Yutaka Tabe,a Takemi Chikahisa,a and Toshihiro Tanumab a Division of Energy and Environmental Systems, Graduate School of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan b Asahi Glass Co., Ltd
The authors investigated the effect of the micro-porous layers (MPL)/catalyst layers (CL) interface, and the results showed that an membrane electrode assembly (MEA) made by the gas diffusion electrode (GDE) method increases the cell voltage under wet conditions over those of an MEA made with the decal method at specific temperature conditions.[19]
Effect of the MPL/CL interface structure on the cell performance.—The polarization curves and resistance of the cells using the GDE and decal transfer method are shown in Figs. 2a and

Summary

Introduction

Yusuke Aoyama,a,z Kengo Suzuki,a Yutaka Tabe,a Takemi Chikahisa,a and Toshihiro Tanumab a Division of Energy and Environmental Systems, Graduate School of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan b Asahi Glass Co., Ltd. These observed results suggest that the produced water passes through the MPL in vapor form under ordinary operating condition regardless of the interface fabrication method as the vapor transport is driven by the saturation pressure gradient for the temperature difference between the MPL.

Results

Conclusion