Enhancing Water Analysis for improved Performance and Durability of Fuel Cell-powered Electric Vehicles

INTRODUCTION
Fuel cell-powered electric vehicles (FCEVs) are gaining increasing interest as a sustainable transportation solution. To achieve faster market penetration and address the challenges faced by FCEVs, significant improvements in their economy, attractiveness, energy efficiency, cost reduction, and durability are necessary. This work focuses on understanding and preventing degradation in FCEVs, with a particular emphasis on the analysis of product water and water management. Water management is a critical aspect of fuel cell technology, playing a vital role in ensuring optimal system performance. Insufficient water management can disrupt the functioning of the system and worsen fuel cell dehydration. Therefore, it is crucial to implement effective strategies for managing water to promote smooth operation and enhance fuel cell efficiency [1]. The current water management practices encounter several challenges at various stages, from the fuel cell itself to the entire fuel cell system. A portion of the water at the fuel cell outlet is redirected for humidifying the feed gases. However, the gas that undergoes anode recirculation has a high dew point, which can result in condensation at the anode when mixed with a gas stream at a lower temperature [2]. Excessive water production can accumulate within the flow channels, as well as the cathode and anode regions. Submerging either the cathode or anode in an excessive amount of water can lead to fuel cell failure [3–5]. Flooding phenomena, characterized by blockages in the flow fields and gas diffusion layers, can cause severe degradation. This leads to fuel starvation, carbon support corrosion, and catalyst degradation [6–8]. Although the inclination of the system can impact flooding, partial condensation is generally tolerable and not measured or quantified. On the other hand, insufficient water content impedes the fuel cell's optimal functioning. These challenges related to water management can be categorized as overflow and dehydration [5]. The voltages during system initiation and idle states can initiate the production of hydrogen peroxide and its corresponding radicals. These radicals possess the capability to break down the membrane, leading to the release of fluoride emissions [7,9].

To address the issues above, this work is set to utilize an open multi-functional modular system as the foundation for further investigations. The exhaust path integrated with a product water sensor should be used to enable the development of a fluoride detection sensor to assess the health of the membrane. Potential strategies for optimizing water management include incorporating heatable optical windows to monitor water transport in the recirculation path and employing optical cells with spectroscopic methods to quantify the presence of liquid water. The findings and optimizations derived from laboratory tests should then be applied to real-world scenarios, particularly in vehicles.



ACKNOWLEDGEMENT
This project is funded by the Climate and Energy Fund and is carried out within the framework of the programme “Zero Emission Mobility”.

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