Interdigitated Flow Field Research Articles

Hydrodynamic and Electrochemical Analysis of Compression and Flow Field Designs in Vanadium Redox Flow Batteries

This numerical study investigates compression and flow field design effects on electrode behaviour in vanadium redox flow batteries (VRFBs). Through 3D simulations and analysis of various flow field designs, including conventional, serpentine, interdigitated, and parallel configurations, this study investigates three compression scenarios: uncompressed, non-homogeneously compressed, and homogeneously compressed electrodes. Hydrodynamic and electrochemical analyses reveal the impact on velocity, pressure, current density, overpotential, and charge–discharge performance. Interdigitated flow field is found to display the lowest charging potential and highest discharging potential among all flow fields under all three compression scenarios. Moreover, uncompressed electrode condition shows the conservative estimates of an average charging potential of 1.3647 V and average discharging potential of 1.3231 V in the case of interdigitated flow field, while compressed electrode condition and the non-homogeneously compressed electrode condition show an average charging potential of 1.3922 V and 1.3777 V, and an average discharging potential of 1.3019 V and 1.3224 V, respectively. Results highlight the significance of non-uniform compression while modelling and analysing the performance of VRFBs as it is a more realistic representation compared to the no-compression or homogeneous compression of the electrodes. The findings of this work provide insights for optimising VRFB performance by considering compression and flow field design.

Engineering Lung-Inspired Flow Field Geometries for Redox Flow Batteries with Stereolithography 3D Printing

Redox flow batteries are a promising electrochemical technology for low-cost, scalable and long-duration energy storage, but their energy market penetration is hampered by elevated costs1,2. One effective strategy is to increase the overall efficiency of the electrochemical stack. At the core of the electrochemical cells, the design of the flow fields—which distribute the electrolyte through the porous electrodes—determines, in combination with the electrode microstructure, the performance of the system3. To date, current designs are inspired on fuel cell technologies but have not been engineered for redox flow cells where single-phase reactive flows are sustained4.In this work, we tailor lung-inspired flow field geometries for carbon paper electrodes using stereolithography 3D printing5,6. We propose two new lung-inspired geometries—with two and three channel levels—and compare them to a baseline interdigitated flow field. A two-step process based on stereolithography 3D printing followed by the application of a conductive coating is used to manufacture these complex flow field geometries. We employ a suite of electrochemical (i.e., polarization and electrochemical impedance spectroscopy) and fluid dynamic (pressure drop measurement) techniques together with numerical modelling to elucidate flow architecture-performance relationships. We find that lung-inspired structural patterns homogenize the electrolyte distribution into the electrode, accessing a larger electrode reaction area. These fractal geometries can outperform traditional interdigitated flow fields, providing a more favourable balance between low pressure drop and high electrochemical performance (Figure 1). In this talk, I aim to leverage lung-inspired flow field geometries as a promising prospect for engineering advanced flow cell architectures for emerging electrochemical devices. References 1 E. Sánchez-Díez, J. Power Sources, 2021, 23.2 L. F. Arenas, C. Ponce de León and F. C. Walsh, J. Energy Storage, 2017, 11, 119–153.3 R. M. Darling and M. L. Perry, J. Electrochem. Soc., 2014, 161, A1381–A1387.4 C. R. Dennison, E. Agar, B. Akuzum and E. C. Kumbur, J. Electrochem. Soc., 2016, 163, A5163–A5169.5 J. Marschewski, L. Brenner, N. Ebejer, P. Ruch, B. Michel and D. Poulikakos, Energy Env. Sci, 2017, 10, 780–787.6 M. P. Browne, E. Redondo and M. Pumera, Chem. Rev., 2020, 120, 2783–2810. Figure 1

Investigating Mass Transfer Relationships in Stereolithography-Based 3D Printed Electrodes for Redox Flow Batteries

Redox flow batteries are a promising option for large-scale energy storage but remain too costly for widespread deployment. One approach to increase cost competitiveness is to improve the power density and efficiency of the electrochemical cell. Porous electrodes determine the performance of the cell, and their three-dimensional structure determines the electrolyte transport, fluid pressure drop, and the available surface area for electrochemical reactions [1]. Conventional porous electrodes are fibrous mats assembled in coherent structures [2]; however, they are repurposed from fuel cell gas diffusion electrodes and have not been tailored for redox flow batteries. Hence, an effective means to improve the performance of redox flow batteries is by engineering porous electrode structures to sustain the requirements of liquid-phase electrochemistry. To this purpose, there is a need to develop new manufacturing techniques affording a higher degree of control over the electrode microstructure and resulting properties. Additive manufacturing, or 3D printing, can be employed to manufacture customized, controlled, and deterministic architectures, enabling the fine-tuning of the electrical and hydraulic performance of porous electrodes [3].In this study, we manufacture model grid structures using stereolithography 3D printing followed by carbonization (Figure 1a) to tune the physiochemical properties of electrodes to be used in redox flow batteries. We employ a suite of microscopy, tomography, spectroscopy, fluid dynamics, and electrochemical diagnostics to understand the impact of the electrode structure on the mass transport and hydraulic performance of ordered lattice structures in flow cells. Here, the influence of the printing direction, pillar geometry (Figure 1b), and flow field type on mass transport is investigated using an organic electrolyte. We elucidate correlations between the electrode structure and performance metrics, namely surface area, pressure drop, and mass transfer correlations. We find that the printing orientation impacts the electrode performance through a change in electrode morphology caused by resin spreading and surface roughness, affecting the shrinking direction upon carbonization, internal surface area, and thus the charge transfer, mass transfer, and hydraulic resistances. Furthermore, we find that mass transfer rates within the electrode are enhanced by using an interdigitated flow field or by altering the pillar shape to a helical or triangular design, which we hypothesize improves mixing. Compared to commercial carbon-fiber electrodes, the pressure drop is significantly reduced (Figure 1c) as expected due to larger pore sizes (~500 μm for the grids vs. 2-100 μm for the Freudenberg H23 paper electrode and 2-300 μm for the ELAT Cloth electrode). Even though the commercial electrodes feature a superior internal surface area compared to the 3D printed electrodes, their area normalized mass transfer coefficients are lower (Figure 1d). Going forward, the use of printing technologies enabling finer features in combination with carbonization at elevated temperatures can be used to manufacture multiscale electrodes simultaneously providing low hydraulic resistance and excellent electrochemical performance. Additive manufacturing in combination with emerging computational approaches in topology optimization [4] might enable the bottom-up design and manufacturing of advanced electrode materials.

Novel Interdigitated Flow Field with a Separated Inlet and Outlet for the Vanadium Redox Flow Battery

Novel Interdigitated Flow Field with a Separated Inlet and Outlet for the Vanadium Redox Flow Battery

A parametric numerical study on the performance of polymer electrolyte membrane fuel cell with intermediate‐blocked interdigitated flow field designs

AbstractFlow field design is crucial for achieving higher performance in polymer electrolyte membrane fuel cells (PEMFCs). This study uses a two‐phase, multi‐component, and three‐dimensional model to simulate the performance of PEMFCs that use interdigitated flow field design with intermediate blocks on the cathode side. A detailed parametric study is presented to investigate the effects of various geometric and operational parameters. Of the parameters studied, inlet mass flow rate, relative humidity, and rib width had the greatest impact on cell performance. The results show that increasing the cathode stoichiometric ratio resulted in higher fuel cell performance for blocked interdigitated designs compared to parallel designs. In addition, using cathode channels with higher height values resulted in lower PEMFC performance for all flow fields. Higher values of rib/channel width ratio resulted in lower cell performance due to liquid water accumulation in the rib regions. However, at higher rib/channel width ratios, the positive effect of using interdigitated flow designs was more pronounced. Moreover, at a low relative humidity of RH = 25%, a 10.4% higher performance was obtained for the interdigitated type II compared to cases with RH = 100%, due to more effective over‐rib convection and higher water removal.

Investigating Mass Transfer Relationships in Stereolithography 3D Printed Electrodes for Redox Flow Batteries

AbstractPorous electrodes govern the electrochemical performance and pumping requirements in redox flow batteries, yet conventional carbon‐fiber‐based porous electrodes have not been tailored to sustain the requirements of liquid‐phase electrochemistry. 3D printing is an effective approach to manufacturing deterministic architectures, enabling the tuning of electrochemical performance and pressure drop. In this work, model grid structures are manufactured with stereolithography 3D printing followed by carbonization and tested as flow battery electrode materials. Microscopy, tomography, spectroscopy, fluid dynamics, and electrochemical diagnostics are employed to investigate the resulting electrode properties, mass transport, and pressure drop of ordered lattice structures. The influence of the printing direction, pillar geometry, and flow field type on the cell performance is investigated and mass transfer vs. electrode structure correlations are elucidated. It is found that the printing direction impacts the electrode performance through a change in morphology, resulting in enhanced performance for diagonally printed electrodes. Furthermore, mass transfer rates within the electrode are improved by helical or triangular pillar shapes or by using interdigitated flow field designs. This study shows the potential of stereolithography 3D printing to manufacture customized electrode scaffolds, which could enable multiscale structures with superior electrochemical performance and low pumping losses.

Engineering Lung-Inspired Flow Field Geometries for Electrochemical Flow Cells with Stereolithography 3D Printing.

Electrochemical flow reactors are increasingly relevant platforms in emerging sustainable energy conversion and storage technologies. As a prominent example, redox flow batteries, a well-suited technology for large energy storage if the costs can be significantly reduced, leverage electrochemical reactors as power converting units. Within the reactor, the flow field geometry determines the electrolyte pumping power required, mass transport rates, and overall cell performance. However, current designs are inspired by fuel cell technologies but have not been engineered for redox flow battery applications, where liquid-phase electrochemistry is sustained. Here, we leverage stereolithography 3D printing to manufacture lung-inspired flow field geometries and compare their performance to conventional flow field designs. A versatile two-step process based on stereolithography 3D printing followed by a coating procedure to form a conductive structure is developed to manufacture lung-inspired flow field geometries. We employ a suite of fluid dynamics, electrochemical diagnostics, and finite element simulations to correlate the flow field geometry with performance in symmetric flow cells. We find that the lung-inspired structural pattern homogenizes the reactant distribution throughout the porous electrode and improves the electrolyte accessibility to the electrode reaction area. In addition, the results reveal that these novel flow field geometries can outperform conventional interdigitated flow field designs, as these patterns exhibit a more favorable balance of electrical and pumping power, achieving superior current densities at lower pressure loss. Although at its nascent stage, additive manufacturing offers a versatile design space for manufacturing engineered flow field geometries for advanced flow reactors in emerging electrochemical energy storage technologies.

An analytical model for parametric study on serpentine and interdigitated flow fields in redox flow batteries

Flow fields can enhance the peak power density of redox flow batteries through distributing the electrolyte and thus reactants uniformly in the porous electrode. However, due to the distinct mechanisms of serpentine and interdigitated flow fields for mass transfer enhancement, the effectiveness of different flow fields is highly dependent on design and operating parameters of the flow cell, such as electrode material, channel's dimension, applied flow rate, and applied current density. The significant computational costs induced by the 3-D or 2-D numerical model on the one hand, and the demand for a deep understanding with respect to the effects of the different flow fields on the flow cell under varying geometric and operating conditions on the other hand, call for an analytical approach. Therefore, the present study establishes an analytical model for quantifying the mass transfer and the electrochemical overpotentials in the flow cell with the serpentine or the interdigitated flow fields. The validity of the analytical model is confirmed by comparisons with experimental and 3-D numerical simulation results under varying electrode materials and channel dimensions. Parametric study results show that the properties changes affect the flow cell implemented with different flow fields paradoxically. First, for the flow cell utilizing electrodes corresponding to a relatively high specific surface area and a low permeability, the interdigitated flow field is more worthy of recommendation, while as the permeability of the electrodes increases, the serpentine flow field becomes more competitive. Second, widening channel's and rib's widths is an effective approach to decrease the concentration overpotential for the interdigitated flow field, while its effects on that with the serpentine flow field is opposite. These results are expected to provide a valuable guidance for the application of interdigitated and serpentine flow fields in flow cells.

The optimal electrode pore size and channel width in electrochemical flow cells

Microfluidic fuel cells, electrolyzers, and redox flow batteries utilize laminar flow channels to provide reactants, remove products and avoid their crossover. These devices often also employ porous flow-through electrodes as they offer a high surface area for the reaction and excellent mass transfer. The geometrical features of these electrodes and flow channels strongly influence energy efficiency. We derive explicit analytical relations for the optimal flow channel width and porous electrode volumetric surface area from the perspective of energy efficiency. These expressions are verified using a two-dimensional tertiary current distribution and porous electrode flow model in COMSOL and are shown to be able to predict optimal parameters in commonly used flow-through and interdigitated flow fields. The obtained analytical models can dramatically shorten modelling time and expedite the industrial design process. The optimal channel width and pore sizes we obtain, in the order of 100 microns and 1 micron respectively, are much smaller than those often used. This shows that there is a significant room for improvement of energy efficiency in flow cells that can sustain the resulting pressure drop.

Measurement of liquid water distribution in GDL under cross-flow-inducing parallel flow field using operando synchrotron X-ray radiography

Baffles in flow field channels for air in a polymer electrolyte fuel cell are known to enhance the performance by inducing convective flow through the gas diffusion layer (GDL) with smaller pressure loss than interdigitated flow fields. This work experimentally correlates performance enhancement with the amount of liquid water in a GDL. A parallel flow field (PFF) that has different inlet and outlet opening sizes is applied to induce cross-flow in the GDL under the rib between adjacent air channels. Operando synchrotron X-ray radiography experiments are conducted to compare the amount of water in the GDL with that for a PFF having the same inlet and outlet sizes. The performance enhancement by application of different opening sizes increases with decreasing relative humidity and increasing air flow rate. A significant performance enhancement is observed when the amount of water in the GDL substrate under the rib becomes almost zero. No performance enhancement is observed under over-humidified conditions, although a decrease in the amount of water in the GDL is still observed, which suggests that the performance becomes insensitive to the difference in the liquid water saturation as the saturation increases.

Review of Flow Field Designs for Polymer Electrolyte Membrane Fuel Cells

The performance of a polymer electrolyte membrane fuel cell (PEMFC) closely depends on internal reactant diffusion and liquid water removal. As one of the key components of PEMFCs, bipolar plates (BPs) provide paths for reactant diffusion and product transport. Therefore, to achieve high fuel cell performance, one key issue is designing BPs with a reasonable flow field. This paper provides a comprehensive review of various modifications of the conventional parallel flow field, interdigitated flow field, and serpentine flow field to improve fuel cells’ overall performance. The main focuses for modifications of conventional flow fields are flow field shape, length, aspect ratio, baffle, trap, auxiliary inlet, and channels, as well as channel numbers. These modifications can partly enhance reactant diffusion and product transport while maintaining an acceptable flow pressure drop. This review also covers the detailed structural description of the newly developed flow fields, including the 3D flow field, metal flow field, and bionic flow field. Moreover, the effects of these flow field designs on the internal physical quantity transport and distribution, as well as the fuel cells’ overall performance, are investigated. This review describes state-of-the-art flow field design, identifies the key research gaps, and provides references and guidance for the design of high-performance flow fields for PEMFCs in the future.

Modification and application of spiral flow fields in vanadium redox flow batteries

A suitable flow field structure could improve the mass transfer inside vanadium redox flow batteries (VRFB). However, previous flow fields based on the serpentine flow field (SFF) or the interdigitated flow field (IFF) with complex structures cannot balance the compromise between pressure drop and overpotential inside VRFBs. To further improve the mass transfer inside VRFBs and efficiently design simpler flow field structures, a 3D model is established for simulating the charge and discharge of VRFBs with different flow fields. After validating the model with experimental and simulated results, we use it to analyze the reason for the weaker performance of VRFB with the origin spiral flow field (OSFF), from which the position and number of the inlet and outlet of OSFF are minimally modified to obtain double spiral flow field with outlets at the center (DSFF(OC)) and double spiral flow field with inlets at the center (DSFF(IC)). Results indicate that under the same flow rate, DSFF(OC) could slightly improve the discharge performance of VRFB compared to SFF, resulting in the lower pressure drops than IFF. When the same pump power is applied, DSFF(OC) and DSFF(IC) both increase the energy efficiency by 7.40 % and 6.21 %, respectively, compared with SFF. Additionally, VRFB with DSFF(OC) exhibits the highest net power efficiency, especially at the lower SOC.

A bifurcate interdigitated flow field with high performance but significantly reduced pumping work for scale-up of redox flow batteries

A bifurcate interdigitated flow field with high performance but significantly reduced pumping work for scale-up of redox flow batteries

A computationally‐cost effective model for fluid flow in redox flow batteries

AbstractRedox flow batteries (RFBs) hold great potential for large‐scale, extended‐duration stationary energy storage. Here, a novel computationally cost‐effective hydraulic‐electrical analogous model (HEAM) for fluid flow in RFBs is developed. The HEAM demonstrated that lowering the electrode compression and enhancing the channel area lowers the pump power loss independent of the flow fields and electrodes. Additionally, the HEAM helped elucidate the deficiencies of flow distribution in interdigitated flow fields (IFFs) and suggested designing wider manifolds and/or shorter channels improve the flow distribution. Moreover, the HEAM suggested shallower and/or wider channels, and more permeable electrodes enhance the flow penetration rate above the channels. Finally, the HEAM showed that the average penetration depth in the electrode above the ribs (hpen) was the critical parameter in the fluid‐flow modeling of IFFs and was inversely proportional to the permeability. Hence, there is a trade‐off between the pump power loss and hpen when configuring electrode permeability.

Effect of Operation Conditions on Current Density Distribution in Interdigitated Flow Fields of Redox Flow Battery

Effect of Operation Conditions on Current Density Distribution in Interdigitated Flow Fields of Redox Flow Battery

Impact of Porous Microstructure on Performance of Redox Flow Batteries: A Modeling Study

Electrodes are essential components of redox flow batteries (RFBs) that determine performance. Given the advances in 3D printing technologies, bottom-up design and manufacturing electrodes with controllable and reproducible properties can be attainable. In this study, pore network modeling is utilized to understand the coupled transport and reaction processes in Hydrogen-Bromine (H2/Br2) flow batteries. This study highlights the importance of the microstructure while designing a 3D printable microstructure. The 3D pore-scale model is validated against the experimental measurements using an unstructured pore network, extracted from a tomography scan of a commercial carbon paper. A printable ordered cubic lattice with the same permeability as carbon paper increases the maximum power density by 35% due to lower tortuosity and higher mass transport. A parametric study is carried out to understand the role of microstructure, such as pore size, throat size, anisotropy, and lattice unit size, for flow-through and interdigitated flow fields. It is shown that a smaller lattice unit, increases the reactive surface area, lowers the activation and mass transport overpotentials, and consequently enhances the performance of the battery. An improved microstructure design for both flow fields is proposed that intensifies the performance of the battery via engineering the flow path of the electrolyte.

Two-layer hydrodynamic network model for redox flow battery stack with flow field design

A two-layer hydrodynamic network model is proposed to analyze the electrolyte distribution within a redox flow battery (RFB). The proposed model consists of a channel, a porous electrode, and an interconnection part through which the electrolyte flows through the channel and porous electrode. The flow rate and pressure drop of each network component are calculated using the Hardy-Cross method. The predicted pressure drop is consistent with experimental and three-dimensional computational fluid dynamics (CFD) results. The velocity and pressure distributions are also in good agreement with CFD results. Furthermore, the proposed model analyzes the flow distribution of cells in RFB stacks with different flow field designs. The results show that the flow rate difference between the first and last cells of the RFB stack with an interdigitated flow field is 20 times higher than that of a flow-through-type.

Numerical modeling of interdigitated flow fields for scaled-up redox flow batteries

Flow fields play a crucial role in determining the electrochemical performance and pumping consumption of flow batteries. In this work, a three-dimensional model coupling fluid flow, mass transport and electrochemical reactions is developed to numerically optimize the interdigitated flow field for high-performance flow batteries. Key design parameters including the aspect ratio (length to width ratio) and the channel fraction are systematically investigated. It is revealed that large aspect ratios and small channel fractions reduce the stagnant zone within the porous electrodes, leading to superior battery performance. However, when the aspect ratio exceeds a critical value, the extremely long and narrow structure leads to uneven distribution of reactants along the channel, thereby resulting in remarkable concentration loss. By taking both the electrochemical loss and pumping consumption into consideration, the flow fields with unit widths from 1.5 to 2.5 mm and channel fractions from 0.125 to 0.375 enable the vanadium redox flow battery to deliver the lowest total power loss. Furthermore, the systematic simulation is also applied to optimize a larger unit with an active area of 540 mm2 for identifying the design principles in the scale-up. It is shown that larger aspect ratios are desirable to alleviate the dramatically increasing pumping loss.

Comparison of Serpentine and Interdigitated Monopolar Plates on the Performance of an Anion Exchange Membrane Fuel Cell By CFD

The continuous energy demand and the growing population have focussed the scientific research on developing alternative energy sources or green fuels.The anion exchange membrane fuel cell (AEMFC) arises as an excellent alternative because of its low-cost electrocatalyst used at the cathode, energy production, and no pollutants emissions to the environment. Nowadays, several studies have been conducted to improve the performance of the AEMFC modifying membrane materials, types of gas diffusion layers (GDL), and catalysts, among other cell components.However, the design of the flow channels by changing plate topologies and materials is still under development. About flow channels topologies, conventional geometries array (pin, straight, parallel, and serpentine) flow fields lead the flow in the direction parallel to the electrode surface, and the reactive gas flow towards the catalyst layer (CL) mainly by molecular diffusion. On the other hand, interdigitated flow fields provide convection velocity normal to the CL and forced convection flow in GDL for better mass transfer. The interdigitated flow fields could prevent water flooding and improve high current density operations performance.These flow fields have been tested in proton exchange membrane fuel cells (PEMFC) with excellent results at low current densities. Nonetheless, there is an essential balance and management of water in an AEMFC. It presents simultaneous production and consumption of water in anode and cathode, respectively, where the production is twice the consumption.Poor water management could provoke anode flooding or membrane drying. These scenarios are undesirable due to mass transport limitations, membrane polymer degradation, and cathodic channels flow can be flooded. Therefore, an appropriate design of flow field that allows the correct water balance on AEMFC is needed for optimal performance. This research deals with the computational fluid dynamic (CFD) comparison of serpentine and interdigitated flow fields on the performance of an AEMFC. For the development of this model, the Navier-Stokes and Brinkmann equations were implemented for momentum transfer. In addition, the average mixture model represents the transport of chemical species, and the Butler-Volmer equation denotes the electrochemical reaction at the CL; water balance is analyzed at low and high current densities to evaluate the scenarios above mention.Preliminary results indicate that a serpentine design is functional at the anode due to the water management is favored. An interdigitated flow field is implemented at the cathode to improve the distribution of the reactants from channels until the CL.

Heratec – Scale-up of Gas Diffusion Layers with Patterned Wettability for Improved Fluid Transport in Hydrogen Fuel Cells

Competitive transport pathways within porous electrodes fundamentally limit the performance of fuel cell devices. While humidification of the system is necessary to provide proton conductivity to the polymeric membrane and ionomer in the catalyst layer, excessive water accumulation in the gas diffusion layer impedes gas transport, resulting in mass transfer performance limitations. In this context, the microstructure and surface chemistry are critical and impact the transport of fluids, mass, charge, and heat, as well as wettability and electrochemical activity. The possibility of creating localized hydrophilic channels for water transport in the gas diffusion layer offers a pathway for advanced strategies to optimize multiphase transport in hydrogen fuel cells. In the past, several techniques have been attempted to create dedicated pathways for water to be transported through the gas diffusion layer, such as layer perforation, local coating deposition, and plasma irradiation [1]–[3]. However, the industrial application of these techniques is limited, due to problems with the mechanical stability, pattern quality, and durability of the applied coating.To approach the problem of water management in polymer electrolyte fuel cells, we have invented a synthetic method based on electron radiation grafting [4]. In previous work, we demonstrated that this tunable method can be readily employed to create gas diffusion layers with patterned wettability [5], [6]. Laboratory experiments demonstrated that the use of patterned gas diffusion layers improved overall fuel cell performance (i.e., power density at high current density) by 10 to 30%, depending on the operating conditions [7]. Moreover, follow-up studies demonstrated that the integration of the modified gas diffusion layer can be used to enable completely new cell design using an interdigitated flow field. Interdigitated flow fields have been demonstrated to substantially improve the cell performance in comparison to conventional cells with parallel flow fields, but current industrial implementation is limited due to stability issues caused by water accumulation in the flow field [8]. The modification of gas diffusion layers with localized wettability demonstrated stable operation of a laboratory-scale cell with very low pressure drop [9]. Finally, the application of patterned GDLs has been proven to enable evaporative cooling, which offers the potential of removing external gas humidification of the cells and cooling fluids [10].Here, we discuss the scale-up potential, industrial application and commercial aspects of our synthetic method to produce gas diffusion layers with localized wettability. In addition, we elucidate the process tunability and discuss the in-situ performance of the manufactured materials. Finally, we present an outlook of our future work focusing on the application of gas diffusion layers with patterned wettability in fuel cells of industry-relevant dimensions and at industry-relevant operating conditions.