Catalyst degradation diagnostics of proton exchange membrane fuel cells using electrochemical impedance spectroscopy

Pivac, Ivan; Bezmalinović, Dario; Barbir, Frano

doi:10.1016/j.ijhydene.2018.05.095

Cited by 51 publications

(22 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The loss of catalyst active area caused by Pt dissolution and sintering due to frequent voltage cycling was selected here as the target for the laboratory experiments as the most relevant for the fuel cell systems in automotive application. Similar test protocols were used in these mentioned projects, and . The voltage was imposed on the cell at 80 °C and 0.5 bar(g) via an external instrument (BioLogic SP 150 potentiostat/galvanostat) as the cell was in a non‐operating (‘driven‘) mode, i.e.…”

Section: Methodsmentioning

confidence: 99%

“…nitrogen (N 2 ) was used on the cathode and hydrogen (H 2 ) on the anode side with constant flows of 0.4 SLPM and inlet relative humidities (RH) of 100% (dew point of 80 °C). The only differences, besides the intentional interruptions, from the AST protocol in were the cell and gas temperatures, which were finally 80 °C, as DOE recommends, because our previous equipment limitations have been adjusted in the meantime.…”

Section: Methodsmentioning

confidence: 99%

“…In literature, degradation (i.e., voltage loss over time) of proton exchange membrane (PEM) fuel cell performance (mechanical, chemical or thermal) mainly refers to irreversible (also called permanent or unrecoverable) performance decay, which could be caused by several degradation mechanisms on various fuel cell components. For automotive fuel cells, typical is degradation of the catalyst layer (CL) caused by carbon corrosion due to frequent starts and stops, loss of catalyst active area caused by platinum (Pt) dissolution and sintering due to frequent voltage cycling, loss of catalyst active area due to adsorption of contaminants from the inlet gases, and/or mechanical degradation due to thermal and humidity cycling induced by the load profile as well as by the environment in which the vehicle operates . However, when the fuel cell exploitation or its durability testing is interrupted due to certain reason, such as equipment maintenance, startup/shutdown procedure, overnight rest, continuous electrochemical in situ testing, etc., a phenomenon of performance recovery could occur, and it has been reported in handful of studies .…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Impact of Shutdown Procedures on Recovery Phenomena of Proton Exchange Membrane Fuel Cells

Pivac

Barbir

2020

Fuel Cells

View full text Add to dashboard Cite

The paper presents the obtained measurement and analysis results of the accelerated stress test protocols consisting of voltage cycling, designed to target electrocatalyst degradation, with the intentional recovery periods (so-called soak time steps) every 2,500 voltage cycles on an already conditioned 50 cm 2 (single) fuel cell provided by ElringKlinger. Before and after every intentional stop, a series of diagnostic methods (polarization curves, electrochemical impedance spectroscopy, cyclic voltammetry, linear sweep voltammetry) were performed. During the conducted durability test, different shutdown procedures, as well as different duration of the soak time period were tested with their impact on perfor-mance recovery phenomenon. The results suggest that cause of the reversible degradation could be accumulated water within the cell and/or presence of oxygen within the catalyst layer leading to formation of platinum oxides on the catalyst surface. The prolonged soak time step reduces recovery effect, while rapid reduction of the cell temperature with ice proved to be counterproductive for performance recovery. Shutdown procedure without shortly-connected resistor has shown no effect on recovery. Shutdown procedure without nitrogen purge proved to be the most effective for performance recovery.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Impact of Shutdown Procedures on Recovery Phenomena of Proton Exchange Membrane Fuel Cells

Pivac

Barbir

2020

Fuel Cells

View full text Add to dashboard Cite

show abstract

“…Pt dissolution reactions [49] ( ) The catalyst degradation can be diagnosed via several techniques; electrochemical impedance spectroscopy (EIS) technique, cyclic voltammetry (CV) technique, SEM-EDX technique, and X-ray photoelectron spectroscopy (XPS). The investigated results from EIS explain the impact of ionic resistance, activation loss (relate to the loss of the electrochemical surface area), and mass transport losses [50]. The CV can be used to diagnose the evaluation of catalyst activity.…”

Section: Degradation Diagnoses Using Accelerated Stress Test (Ast) Prmentioning

confidence: 99%

Hydrogen Fuel Cell Implementation for the Transportation Sector

Yeetsorn¹,

Maiket²

2021

Advanced Applications of Hydrogen and Engineering Systems in the Automotive Industry

View full text Add to dashboard Cite

Global transportation possesses have compelling rationales for reducing the consumption of oil, emissions of carbon dioxide, and noise pollution. Transitions to alternative transportation technologies such as electric vehicles (EVs) have gained increased attention from the automotive industries. A fuel cell electric vehicle (FCEV) occupying a hydrogen engine is one of the most stupendous technologies, since it is suitable for a large-scale transportation. However, its performance limitations are in question due to voltage degradation in long term operations through steady conditions under constant load and dynamic working conditions. Other drawbacks of using fuel cells in EVs are energy balances and management issues necessary for vehicle power and energy requirements. An efficient solution to accommodate driving behavior like dynamic loads comprises of hybridizing PEMFCs with energy storage devices like supercapacitors and batteries. This opening chapter reviews the projected gist of FCEV status; considers the factors that are going to affect how FCEVs could enter commercialization, including the importance of fuel cells for EV technologies; the degradation diagnoses using accelerated stress test (AST) procedures; FCEV hybridization; and the contribution of an energy storage device for charging EVs. The article also addresses case studies relating to material degradation occurring from driving behavior. Information about material degradation can be compiled into a database for the improvement of cell component performance and durability, leading to the creation of new materials and new fuel cell hybridization designs. To support the growth of EV technologies, an energy storage is required for the integrated alternative electricity generations. A redox flow battery is considered as a promising candidate in terms of attractive charging station for EVs or HEVs.

show abstract

“…The high frequency resistance (HFR), which is determined from the high-frequency intercept with the real axis of the Nyquist plots (obtained from the EIS measurements as outlined in section 2.6) in Fig. 7, provides a measure of the ohmic resistance and is predominantly attributed to the membrane hydration and its associated conductivity [59,60]. Fig.…”

Section: Impedance Measurementsmentioning

confidence: 99%

A lung-inspired printed circuit board polymer electrolyte fuel cell

Bethapudi

Hack

Trogadas

et al. 2019

Energy Conversion and Management

View full text Add to dashboard Cite

Fractal cathode flow-fields, inspired by the flow mechanism of air inside lungs, can provide homogeneous, scalable and uniform distribution of reactants to polymer electrolyte fuel cell (PEFC) electrodes. However, the complex 3D flow-fields demonstrated previously face manufacturing challenges, such as requiring selective laser sintering, an additive manufacturing method that is expensive to scale up. Here, a lung-inspired cathode flow-field is introduced and fabricated using low-cost, lightweight printed circuit boards (PCB). The uniformity and alignment between individual PCB layers producing the fractal hierarchy of flow channels have been characterised using X-ray computed tomography (X-ray CT). The performance of the fractal flow-field exceeds that of conventional single-serpentine flow-fields and is particularly beneficial when operating on air with a low relative humidity. The lung-2 inspired design is shown to lead to a more stable operation than the single-serpentine design, as a result of uniform distribution of reactants.

show abstract

Catalyst degradation diagnostics of proton exchange membrane fuel cells using electrochemical impedance spectroscopy

Cited by 51 publications

References 18 publications

Impact of Shutdown Procedures on Recovery Phenomena of Proton Exchange Membrane Fuel Cells

Impact of Shutdown Procedures on Recovery Phenomena of Proton Exchange Membrane Fuel Cells

Hydrogen Fuel Cell Implementation for the Transportation Sector

A lung-inspired printed circuit board polymer electrolyte fuel cell

Contact Info

Product

Resources

About