Performance Recovery in Irreversibly Degraded Polymer Electrolyte Membrane Fuel Cell for Enhanced Water Management

Abstract

Polymer electrolyte membrane fuel cells (PEMFCs) offer numerous advantages, such as low operating temperatures, ease of start-up and shutdown, and high power density. Recent researches have focused on enhancing their performance for various industrial applications, particularly in transportation fields including vehicles and drones. The gas diffusion layer (GDL) in PEMFC plays a key role in the transport of fuel, oxygen, and water. The physical and chemical degradation of GDL adversely affects the water management resulting in performance deterioration. A major cause of GDL degradation in PEMFCs is the generation of hydrogen peroxide (H₂O₂) during the electrochemical reaction. H₂O₂ lead PTFE loss and carbon corrosion, and this degradation is irreversible. Although several studies demonstrate techniques for recovering performance for the reversible degradation, limited research exists on restoring performance in irreversibly degraded PEMFCs. This study proposes a novel approach for the performance recovery in irreversibly degraded PEMFCs by superimposing acoustic pressure waves on the oxygen gas flow which enhances the water management ability [1]. To investigate the effect of proposed recovery technique, performances were compared with or without the superimposed acoustic pressure waves using a unit cell having 25 cm² active area. The 19 % decrease in performance with aged GDL was observed due to the reduction in the water management capability caused by the decrease of hydrophobicity. The superimposed acoustic pressure waves led to a performance recovery of up to 9. This recovery is attributed to the enhanced removal of accumulated water on the GDL surface through external excitation, which facilitated oxygen supply and improved water discharge. The proposed the water management method can offer a promising solution for recovering performance in irreversibly degraded PEMFCs and has the potential to improve both performance and durability. Acknowledgement This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT) (No. RS-2023-00208497, RS-2023-00219369). Reference [1] Kim, J. Y., Mortazavi, M., & Jung, S. Y. (2024). Improving polymer electrolyte membrane fuel cell performance and preventing flooding by exciting gas flow. Journal of Power Sources , 617 , 235181.

Key findings

• ▸Irreversible degradation of GDL in PEMFCs is caused by hydrogen peroxide generation, leading to PTFE loss and carbon corrosion.
• ▸Existing techniques focus on reversible degradation recovery, but limited research addresses irreversibly degraded PEMFCs.
• ▸Acoustic pressure waves applied to oxygen gas flow enhance water management and recover performance in irreversibly degraded PEMFCs.

Keywords

Identifiers

DOI

10.1149/ma2024-02505049mtgabs

Journal

ECS Meeting Abstracts

Year

2024