Embedded Files
Parametric Sensitivity of a PEM Electrolyzer Mathematical Model: Experimental Validation on a Single-Cell Test Bench
Parametric Sensitivity of a PEM Electrolyzer Mathematical Model: Experimental Validation on a Single-Cell Test Bench
In this study, a discrete dynamic mathematical model of a PEMWE was developed in MATLAB/Simulink to simulate cell performance under various operating conditions such as temperature, inlet flow rate, and current density loads. A lab-scale test bench was designed and set up, and a 5 cm² PEMWE was tested at different temperatures (40–80 °C) and flow rates (3–12 mL/min), obtaining Linear Sweep Voltammetry (LSV), Cyclic Voltammetry (CV), Chrono-potentiometry (CP), and Electrochemical Impedance Spectroscopy (EIS) results for comparison and adjustment of the dynamic model. Sensitivity analysis of different operating variables confirmed that current density and temperature are the most influential factors affecting cell voltage. The parametric sensitivity of various chemical–physical and electrochemical parameters was also investigated. The most significant ones were estimated via non-linear least squares optimization to fine-tune the model. Additionally, strong correlations between these parameters and temperature were identified through regression analysis, enabling accurate performance prediction across the studied temperature range.
Both water electrolysis and electrochemical energy storage are promising technologies for dealing with the intermittency of green electricity generation. In this work we investigated the possibility of using the same electro-catalyst for hydrogen production by Anion Exchange Membrane Water Electrolysis (AEMWE) and energy storage by Redox Flow Batteries (RFB). A complete experimental campaign was designed to investigate the effects of the catalyst nanostructure and morphology on the electrode performance at different scales. Focus was devoted to the choice of the main factors influencing the catalyst structure, its morphology and electrochemical activity; taking further into account the technique to deposit the catalyst on the Gas Diffusion Layer (GDL) and its integration inside the Membrane Electrode Assembly (MEA). Some results are reported for a spinel-based NiCo2O4 catalyst, chosen as a base nanocomposite to develop more complex materials for both the Oxygen Evolution Reaction (OER) in AEMWE and the positive electrode in Vanadium RFB in the future.
Transition metals such as nickel and cobalt as an alternative to Pt and Pd can be used for oxygen evolution reactions (OERs) and hydrogen production reactions (HERs) in alkaline environments, facilitating green hydrogen production as a sustainable alternative to fossil fuels. In this study, an NiCo2O4 catalyst was produced by a sono-hydrothermal method using urea as a hydrolysis agent. The electrochemical performance of the catalyst-coated NiFelt electrode was evaluated at different KOH concentrations (0.25, 0.5, and 1 M) and four operating temperatures in the interval of 20–80 °C. The electrode characteristics were investigated via electrochemical spectroscopy (cyclic voltammetry, EIS, multistep chronopotentiometry, multistep chronoamperometry) using two different reference electrodes (Ag/AgCl and Hg/HgO), to obtain insight into the anodic and cathodic peaks. XRD, SEM, EDS, and TEM analyses confirmed the purity, structure, and nanoscale particle size (20–45 nm) of the NiCo2O4 catalyst. The electrode showed symmetric CV with Ag/AgCl, making this reference electrode more appropriate for capacitance measurements, while Hg/HgO proved advantageous for EIS in alkaline solutions due to reduced noise. The overpotential of the catalyst-coated NiFelt decreased by 108 mV at 10 mA/cm2 compared to bare NiFelt, showing a good potential for its application in anion exchange membranes and alkaline electrolyzers at an industrial scale.
Investigating the Impact of Electrolyte Temperature on the Oxygen Evolution Reaction Efficiency Using Ni-Co/Ni Felt Nano Composite Electrodes.
Investigating the Impact of Electrolyte Temperature on the Oxygen Evolution Reaction Efficiency Using Ni-Co/Ni Felt Nano Composite Electrodes.
This study investigates the impact of electrolyte temperature on the electrochemical behavior of Ni-Co nanocomposite electrodes supported by NiFelt in an alkaline water electrolyzer setup. Using a three-electrode configuration, the effects of temperature variations (20-80°C) on electrocatalyst stability and reaction kinetics were evaluated. Results indicate higher temperatures enhance OER kinetics but compromise reaction stability due to increased conductivity and active sites. This research underscores the importance of optimizing electrolyte temperature for industrial AWE applications.
This research investigates the twisting behavior of a multi-layered hydrogel-based actuator comprised of two temperature-sensitive hydrogel layers and one elastomeric layer as the main core in different aspects due to temperature changes. Firstly, a suitable model is implemented for the temperature-sensitive hydrogel in the ABAQUS software using the UHYPER subroutine. Then, twisting behavior of the actuator due to temperature changes is simulated, and the twisting angle and reaction torque are obtained for the actuators. A comprehensive parameter study is conducted to investigate the effect of different material and geometric parameters on the performance of the actuator. These parameters include the cross-linking density of the hydrogel, the volumetric percentage of the hydrogel, the geometry of the interface line of the layers, and the aspect ratio (cross-section dimensions) of the actuator. The results identify the actuators with the maximum twisting angle and maximum reaction. In brief, the reaction torque generated at the ends of the twisting actuator is the maximum for the case where the interface line passes through the corners of the actuator cross-section. The results also show that for the maximum twisting angle of the studied actuator, the so-called interface line should not pass through the actuator corners.
Page updated
Google Sites
Report abuse