Assessing Durability in Automotive Fuel Cells: Understanding the Degradation Patterns of PEM Fuel Cells Under Variable Loads, Temperature, Humidity, and Defective Stack Conditions

TY - JOUR

T1 - Assessing Durability in Automotive Fuel Cells

T2 - Understanding the Degradation Patterns of PEM Fuel Cells Under Variable Loads, Temperature, Humidity, and Defective Stack Conditions

AU - Dhimish, Mahmoud

AU - Lazarov, Vlado

N1 - © 2024 IEEE. This is an author-produced version of the published paper. Uploaded in accordance with the University’s Research Publications and Open Access policy.

PY - 2024/7/23

Y1 - 2024/7/23

N2 - This paper embarks on an analytical exploration of the degradation mechanisms affecting the proton exchange membrane (PEM) fuel cell with 3.2 kW capacity, pivotal in hybrid systems of Toyota vehicles and electric scooters. Through rigorous experimentation, we quantitatively dissect the impact of varying operational conditions–humidity (25% to 100% RH), temperature (45°C to 75°C), and load (half-load to over-load)—on fuel cell efficiency and longevity. Notably, our findings reveal that humidity levels above 75% RH precipitate a stark efficiency decline at higher current densities due to exacerbated internal resistance, with a degradation rate peaking at -0.019%/day under optimal conditions and escalating significantly under adverse conditions. Temperature variations further illuminate the critical balance between performance and durability, with the highest stability observed at 55°C, manifesting in a moderated degradation rate of -0.024%/day, contrasting sharply with the -0.124%/day observed under over-load scenarios. Structural integrity analysis, facilitated by scanning electron microscope (SEM) imaging, identified two distinct defect types, directly correlating to degradation rates of -0.0384%/day and -0.0552%/day, respectively. This comprehensive study provides pivotal insights into fuel cell operational efficiency, unveiling specific degradation rates and operational thresholds that demarcate resilience from rapid decline, thereby guiding the future of sustainable fuel cell technology in transportation.

AB - This paper embarks on an analytical exploration of the degradation mechanisms affecting the proton exchange membrane (PEM) fuel cell with 3.2 kW capacity, pivotal in hybrid systems of Toyota vehicles and electric scooters. Through rigorous experimentation, we quantitatively dissect the impact of varying operational conditions–humidity (25% to 100% RH), temperature (45°C to 75°C), and load (half-load to over-load)—on fuel cell efficiency and longevity. Notably, our findings reveal that humidity levels above 75% RH precipitate a stark efficiency decline at higher current densities due to exacerbated internal resistance, with a degradation rate peaking at -0.019%/day under optimal conditions and escalating significantly under adverse conditions. Temperature variations further illuminate the critical balance between performance and durability, with the highest stability observed at 55°C, manifesting in a moderated degradation rate of -0.024%/day, contrasting sharply with the -0.124%/day observed under over-load scenarios. Structural integrity analysis, facilitated by scanning electron microscope (SEM) imaging, identified two distinct defect types, directly correlating to degradation rates of -0.0384%/day and -0.0552%/day, respectively. This comprehensive study provides pivotal insights into fuel cell operational efficiency, unveiling specific degradation rates and operational thresholds that demarcate resilience from rapid decline, thereby guiding the future of sustainable fuel cell technology in transportation.

KW - Fuel cells

KW - Renewable energy

KW - Fuel cell multi-stack

KW - Degradation

U2 - 10.1109/TTE.2024.3434609

DO - 10.1109/TTE.2024.3434609

M3 - Article

SN - 2332-7782

JO - IEEE Transactions on Transportation Electrification

JF - IEEE Transactions on Transportation Electrification

ER -