Investigation of Corrosion Methods for Bipolar Plates for High Temperature Polymer Electrolyte Membrane Fuel Cell Application

Nadine Pilinski,Peter Wagner,Claudia Käding,Alexander Dyck,Anastasia Dushina,Thorsten Hickmann

doi:10.3390/en13010235

Nadine Pilinski, Peter Wagner + Show 4 more

Open Access

https://doi.org/10.3390/en13010235

Copy DOI

Journal: Energies	Publication Date: Jan 3, 2020
Citations: 7	License type: CC BY 4.0

Affiliation: Eisenhuth (Germany)

Abstract

In this work, different methods and electrochemical set-ups were investigated in order to study the corrosion behaviour of bipolar plates (BPP) for high temperature (HT) polymer electrolyte membrane fuel cell application. Using confocal and scanning electron microscopy, it was shown that chemical and electrochemical aging significantly increases surface roughness as well as morphology changes, confirming material degradation. Identical electrochemical corrosion behaviour was observed for both set-ups with typical quinone/hydroquinone peaks in the potential range ~0.6–0.7 V versus reversible hydrogen electrode (RHE). The appearance of the peaks and an increase of double layer capacitance can be related to the oxidation of carbon surface and, consequently, material corrosion. Simultaneously, an optimised corrosion set-up was introduced and verified regarding suitability. Both investigated set-ups and methods are useful to analyse the oxidation behaviour and corrosion resistance.

Highlights

The increasing interest in renewable energy sources has driven the development of high temperature polymer electrolyte membrane (HT-PEM) fuel cells (FCs) with regard to their minimal emissions, low weight, and better tolerance to fuel impurities [1,2]
The root means squareThe surface roughness was calculated mentioned asoftware rubber-ring hermetic closing that allows having contact for mean the working electrodeofand after for levelling the confocal microscopy image.aItproper is defined as root square average the the Teflon lid,deviations enabling the electrochemical to be measured in highwere concentrated phosphoric profile height from the mean line.response
The Teflon sample holder (Figure 1b) for the bipolar plates (BPP) contains a rubber-ring for hermetic closing that allows having a proper contact for the working electrode and the Teflon lid, enabling the electrochemical response to be measured in high concentrated phosphoric acid

Summary

Introduction

The increasing interest in renewable energy sources has driven the development of high temperature polymer electrolyte membrane (HT-PEM) fuel cells (FCs) with regard to their minimal emissions, low weight, and better tolerance to fuel impurities [1,2]. These type of BPPs have advantages over graphite and metallic materials regarding their low weight, flexibility, and corrosion resistance [14] They can be produced by several economically beneficial methods including compression, transfer, or injection moulding processes [17]. The composite graphite BPPs consist of one of the conventional polymers—such as polyethylene, polypropylene, polyphenylene sulphide (PPS), or phenol formaldehyde resin—and graphite-based components, providing the mechanical stability and electrical conductivity, respectively [14]. Some challenges, such as higher thickness and weight as well as lower electrical conductivity in comparison with metallic bipolar plates, limit the use of polymer–graphite plates in automotive application [3]. Confocal microscopy and scanning electron microscopy (SEM) were used to determine surface roughness and morphological changes after the stress test

BPP Samples

Imaging Methods

Chemical and

Method II

Results and Discussion

Method I

Conclusions