Applicability of nitrogen separation membrane modules for inertization of the PEM fuel cell stack

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F18%3A43916115" target="_blank" >RIV/60461373:22310/18:43916115 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60461373:22310/18:43916117

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Applicability of nitrogen separation membrane modules for inertization of the PEM fuel cell stack

Popis výsledku v původním jazyce

Inertization at the end of active period represents an important part of operating PEM fuel cell (FC) stack. This part of the FC operational cycle is important both from life time and safety point of view. Significance of this step increases with decreasing thickness of the polymer electrolyte membranes used for the stack construction. This is given by increasing permeability of such membranes for hydrogen. This, especially during off period, results in formation of aggressive species in the catalytic layers of the gas diffusion electrodes enhancing their chemical degradation. As the hydrogen is removed from the FC interior and at the same time diluted during inertization, related dangers are avoided. The traditional media for FC inertization is nitrogen. It can be stored in a high pressure cylinders integrated into the FC system. Such solution, however, is demanding due to the more reasons. As main of them following ones may be mentioned. Installation of such cylinder increases complexity and weight of entire system. At the same time, total volume of gas in cylinder is sufficient just for a limited number of inertization cycles before replacement or refilling is required. It makes the process complicated also from logistics point of view. An alternative solution represents production of nitrogen of sufficient purity on-site, preferably from air by means of membrane separations modules. In combination with corresponding compressing unit it represents inexhaustible source of nitrogen. Unfortunately, the membrane module is not able to produce nitrogen at purity higher than 99.9 %. As it follows from composition of the air, oxygen represents main impurity in the produced nitrogen stream. Information available in literature on the impact of traces of oxygen in an inertization gas on the FC stack life time and performance is, however, not sufficient yet. Thus, in the present work the impact of the oxygen residuals in an inertization nitrogen stream on performance of commercially available MEAs was followed by means of selected nitrogen production membrane modules under various operational conditions. The results obtained allow assessing viability of this approach for practical application in a field of small scale portable APU on the base of hydrogen fueled PEM FC.

Název v anglickém jazyce

Applicability of nitrogen separation membrane modules for inertization of the PEM fuel cell stack

Popis výsledku anglicky

Inertization at the end of active period represents an important part of operating PEM fuel cell (FC) stack. This part of the FC operational cycle is important both from life time and safety point of view. Significance of this step increases with decreasing thickness of the polymer electrolyte membranes used for the stack construction. This is given by increasing permeability of such membranes for hydrogen. This, especially during off period, results in formation of aggressive species in the catalytic layers of the gas diffusion electrodes enhancing their chemical degradation. As the hydrogen is removed from the FC interior and at the same time diluted during inertization, related dangers are avoided. The traditional media for FC inertization is nitrogen. It can be stored in a high pressure cylinders integrated into the FC system. Such solution, however, is demanding due to the more reasons. As main of them following ones may be mentioned. Installation of such cylinder increases complexity and weight of entire system. At the same time, total volume of gas in cylinder is sufficient just for a limited number of inertization cycles before replacement or refilling is required. It makes the process complicated also from logistics point of view. An alternative solution represents production of nitrogen of sufficient purity on-site, preferably from air by means of membrane separations modules. In combination with corresponding compressing unit it represents inexhaustible source of nitrogen. Unfortunately, the membrane module is not able to produce nitrogen at purity higher than 99.9 %. As it follows from composition of the air, oxygen represents main impurity in the produced nitrogen stream. Information available in literature on the impact of traces of oxygen in an inertization gas on the FC stack life time and performance is, however, not sufficient yet. Thus, in the present work the impact of the oxygen residuals in an inertization nitrogen stream on performance of commercially available MEAs was followed by means of selected nitrogen production membrane modules under various operational conditions. The results obtained allow assessing viability of this approach for practical application in a field of small scale portable APU on the base of hydrogen fueled PEM FC.

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

10405 - Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)

Projekt

<a href="/cs/project/VI20152019018" target="_blank" >VI20152019018: Vývoj a realizace nezávislého DC zdroje napájení s vodíkovým palivovým článkem</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů