bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Degradation Processes in Alkaline and PEM Water Electrolyzers
Authors: Sánchez Batalla Beatriz , Mariappan Sakthivel , Bogolowski Nicky , Weidlich Claudia , Drillet Jean-Francois
Published: February 2024

In the struggle against climate change, hydrogen has been considered as a key player, since it can be used as a fuel in electrochemical devices, but also as feed in the chemical and metallurgical industry. However, only if this hydrogen is produced by CO2-free process, the net zero-emission goals will be achieved. Green hydrogen can be obtained by water electrolysis using renewable electricity as power source. While alkali (AEL) and acid (PEMEL) electrolyzers are the most advanced technologies, further improvements especially in terms of catalyst stability are still needed to increase their lifetime and economical profitability for megawatt and gigawatt scaling-up.

In this work, we report on electrochemical degradation tests of commercially available AEL and PEMEL single cells with 5 cm2 active, geometrical surface. The AEL anode and cathode consist of Raney-Ni electrodes with PTFE binder supported on a Ni grid, separated by a Zirfon diaphragm. 30% KOH at 80°C was used as electrolyte in both chambers. The commercial catalyst coated membrane (CCM) for PEMEL consists of 2 mgIr/cm2 anode and 1 mgPt/cm2 cathode coated on Nafion N117. Titanium felt and carbon paper were used as porous transport layers in the anode and cathode side, respectively. Ultrapure water at 60 °C was used as electrolyte in both sides. For long-term electrochemical tests, current density of 0.5 A/cm2 and 2 A/cm2 was applied to the AEL and PEMEL cells, respectively, for 1000 h. Since at nominal current density, low degradation rate was expected, accelerated degradation tests (ADT) were performed at two identical cells by using triangular polarization profile aiming to reflect dynamic electrolyzer operation in case of e.g., direct coupling with wind turbine. Thereby, the current density was varied between 0.05 - 1 A/cm2 for AEL and 0.05-3 A/cm2 for PEMEL for at least 1000 h. After each 100 h period during both constant and triangular polarization experiments, the cell was electrochemically characterized by impedance spectroscopy and current/voltage (UI) profiles and anolyte and catholyte were collected for ICP-OES measurements in order to evaluate dissolved species. After test, the cells were disassembled and the cell components were analyzed by SEM/EDX, XRD and XPS technique. By correlating the physicochemical with the electrochemical changes in the components of the cell, main degradation mechanisms will be exposed.
Revealing the Impact of Cell Conditioning on PEMWE Catalyst Layer Morphology
Authors: Seip Tess , Hasan Ahmed Moayad , Parmar Harsharaj Birendrasingh , Zhu Lijun , Lytle Spencer , Wang Jian , Hitchcock Adam , Shaigan Nima , Dinu Marius , Fatih Khalid , Lytle Spencer , Bazylak Aimy
Published: February 2024

Polymer electrolyte membrane (PEM) water electrolysis is a promising green hydrogen generation technology to mitigate the effects of anthropogenic climate change. To achieve stable cell voltages, a conditioning procedure is typically required, where current or voltage cycling is applied until stable performance is achieved. Previous studies have demonstrated that a decrease in voltage occurs within the first few hours of operation [1], but this conditioning period has not been extensively studied for PEM electrolyzers, despite a variety of standard conditioning protocols available for PEM fuel cells in the literature. Previous works additionally suggest that changes in performance may be induced due to structural changes in the anode catalyst layer (CL) caused by large gas bubble evolution during the first few hours of operation [2]. However, to establish and optimize a conditioning procedure for PEMWEs, the specific structural changes caused by conditioning on the anode CL must be elucidated and correlated with the electrochemical performance parameters.

In this work, we applied scanning transmission X-ray microscopy (STXM) to PEMWE catalyst layers to reveal pore and ionomer distributions in pristine and conditioned commercial CL samples. Prior to imaging, CL samples were embedded in epoxy and cut to 50 nm thick slices using an ultramicrotome. Using near-edge X-ray absorption fine structure (NEXAFS) spectroscopy, Carbon 1s and Fluorine 1s absorption edges were probed to reveal pore and ionomer distributions, respectively. After image acquisition, the image stacks were processed to obtain the ionomer and epoxy spectra to enable spectral fitting and thresholding. Through this analysis, we quantified various morphological properties of catalyst layers (including CL thickness, porosity, pore size distribution, agglomerate distribution, and ionomer content) and compared these properties to those of pristine CLs to explain changes in cell performance. The insights gained from this work will aid in the development of efficient conditioning protocols and identify optimal post-conditioned anode CL morphology to inform the design of next-generation catalyst materials.

A. Weiß et al., J Electrochem Soc, 166, F487–F497 (2019).

O. Panchenko et al., Mater Today Energy, 16, 100394 (2020).
Microporous Transport Layers Facilitating Low Iridium Loadings in Polymer Electrolyte Water Electrolyzers
Authors: Weber Carl Cesar , Meinert Robin , Appel Christian , Holler Mirko , Gubler Lorenz , De Angelis Salvatore , Buechi Felix N.
Published: February 2024

Minimizing iridium content in the anodic catalyst layer (CL) of polymer electrolyte water electrolyzers (PEWE) is essential for facilitating the needed rapid scale-up of hydrogen production capacity. However, reducing the iridium loading inevitably produces thinner CLs (if not changing the catalyst itself). This can have severe effects on performance and stability, mainly due to the losses in the connectivity of the 3D structure. Microporous layers (MPLs) have the potential to improve the performance and catalyst layer utilization of PEWE cells[1], especially at low Ir-loadings since they minimize the in-plane transport length of the required species (i.e. electric and fluidic transport).

In this work, we characterized the 3D structure and transport properties of typical IrO2/TiO2 core-shell PEWE catalyst layers[2] by synchrotron-based ptychographic X-ray laminography (PyXL)[3]. Furthermore, we fabricated CLs at different Ir-loadings between 2.5 – 0.1 mgIr cm-2 depositing them either on the membrane i.e. catalyst-coated membranes (CCM) or on the MPL/PTL i.e. porous transport electrode (PTE). We tested the electrodes in PEWE cells using novel MPLs and standard commercial porous transport layers (PTLs) and compared their electrochemical performance and overpotentials. We observe that ultra-low iridium loadings (0.1 mgIr cm-2) with only relatively small setbacks in performance are possible when using Pt-coated MPLs. Moreover, we correlate the electrochemical results with the 3D structure of the CL by PyXL and the MPL/CL interface by lab-based X-ray tomographic microscopy (Figure 1). Finally, we will discuss the challenges of fabricating low-loaded anodic CLs in CCM and PTE configuration and the advantages of using an MPL in both scenarios.

[1] T. Schuler, J. M. Ciccone, B. Krentscher, F. Marone, C. Peter, T. J. Schmidt, F. N. Büchi, Adv. Energy Mater.
2020, 10, 1903216.

[2] S. De Angelis, T. Schuler, M. Sabharwal, M. Holler, M. Guizar-Sicairos, E. Müller, F. N. Büchi, Sci Rep
2023, 13, 4280.

[3] M. Holler, M. Odstrcil, M. Guizar-Sicairos, M. Lebugle, E. Müller, S. Finizio, G. Tinti, C. David, J. Zusman, W. Unglaub, O. Bunk, J. Raabe, A. F. J. Levi, G. Aeppli, Nature Electronics
2019, 2, 464.

Figure 1. Surface renderings from XTM/PyXL and SEM images of porous transport electrodes (PTE, left) and catalyst-coated membranes (CCM, right) of selected samples used in this work.

Figure 1
Promoting AEM Water Electrolyzer Performance and Reproducibility by Tumbler Milling of Ni3fe-LDH OER Catalyst
Authors: Galkina Irina , Faid Alaa Y. , Grigorev Nikita , Jiang Wulyu , Borowski Patrick , Sunde Svein , Shviro Meital , Lehnert Werner , Mechler Anna K. , Scheepers Fabian
Published: February 2024

Anion exchange membrane water electrolysis is an attractive clean energy technology for producing hydrogen for energy storage, transport 1,2 and numerous other applications. Rational choice of highly active and stable catalysts as well as the proper design of catalyst layers are crucial to achieve technical relevance of electrolyser systems. The establishment of clear understanding of optimal catalyst treatment and methods of implementation are key steps towards optimized electrolyzer performance and durability. One aspect of catalyst performance in catalyst layers is the catalyst size distribution. A multimodal size distribution of catalyst particles or agglomerates can jeopardize the layer homogeneity and thus electrode performance.

In this work, the effect of high-energy ball tumbling milling on the promising Ni3Fe-LDH OER catalyst followed by catalyst dispersion control was correlated to the microstructure of the catalyst layer, the achieved catalyst activity and utilization, and the resulting single cell performance and stability. Physico-chemical characterization confirmed the stable layered double hydroxide structure of the catalyst. By milling, a 300-fold reduction of catalyst agglomerate size, and an 8.8-fold increase of the geometrical surface was achieved. The optimized solvent compositions effectively increased the catalyst ink stability. We found that a significantly decreased catalyst agglomerate size resulted in very homogeneous mixtures of catalyst and ionomer. By tailoring the electrode structure design, lower internal electronic resistances of the electrodes, decreased charge-transfer resistances (Rct) of the membrane electrode assembly, and stable single cell durability of 1000 h with a minor degradation rate of 57 µV h-1 were accomplished.

This work presents a facile and scalable approach of NiFe-LDH catalyst treatment and dispersion control and provides a guideline to follow for further electrode development and increased AEM water electrolyzer performances.

References

(1) Hydrogen Applications. Hydrogen Europe. 2020. https://hydrogeneurope.eu/hydrogen-applications (accessed Jan 7, 2022).

(2) Vincent, I.; Bessarabov, D. Low Cost Hydrogen Production by Anion Exchange Membrane Electrolysis: A Review. Renew. Sustain. Energy Rev.
2018, 81 (August 2016), 1690–1704. https://doi.org/10.1016/j.rser.2017.05.258.

This work has been performed in the frame of the CHANNEL project. This project has received funding from the Fuel Cells and Hydrogen 2 Joint Undertaking (now Clean Hydrogen Partnership) under grant agreement No 875088. This Joint undertaking receives support from the European Union's Horizon 2020 Research and Innovation program, Hydrogen Europe and Hydrogen Europe Research.
Oxygen Evolution Reaction with ZrCo and ZrNi Electrode Materials
Authors: Le Tonquesse Sylvain , Altendorf Simone , Grin Yuri , Antonyshyn Iryna
Published: February 2024

Investigation of the intermetallic compounds as anode materials for water electrolysis helps to solve a lot of issues, which electrocatalysis and solid state chemistry communities face nowadays. Intermetallic compounds possess unique properties in terms of their crystal structure, electronic properties and chemical bonding, allowing the knowledge-based route for electrocatalyst development. Furthermore, usage of the single-phase anode material is a way to exclude the influence of interface as well as nature and stability issues of the support. At the same time, studies of the intermetallic compounds under the reaction conditions shed light onto the chemical properties of the intermetallic compounds, which are scarcely described in literature and of particular importance for solid state chemistry field.

In this study, binary intermetallic compounds ZrCo and ZrNi were studied as anode materials for alkaline water electrolysis. The successful synthesis of single-phase samples of both compounds was followed by manufacturing of the cylindrically-shaped electrodes using spark plasma sintering technique. The assessment of the electrocatalytic performance was carried out in three-electrode cell, applying different measurement protocols, giving the information about OER activity of studied materials, its stability over time as well as other electrochemical features, giving the information about the processes occurring on the electrode surfaces. To monitor the material changes under conditions of OER, the electrodes were comprehensively characterized before and after the electrochemical experiments using bulk- and surface-sensitive techniques. Combined data was discussed and compared with state-of-the-art OER electrocatalysts for alkaline media.
Research and Innovation Activities on PEM Fuel Cells and Electrolysers Supported by the Clean Hydrogen Partnership
Authors: Pavel Claudiu , Lymperopoulos Nikolaos , Kontonasiou Eleni , Feola Luca , Sakellaris Kostis , Atanasiu Mirela
Published: February 2024

The Clean Hydrogen Partnership — the successor of the Fuel Cells and Hydrogen Joint Undertaking (FCH JU) — aims to contribute to EU Green Deal and Hydrogen Strategy by providing financial support for research and innovation activities in the field of advanced clean hydrogen technologies. It builds on 15 years of strategic cooperation between public and private sectors enabling several innovative technologies to advance from the experimental scale closer to maturity.

The projects funded under the previous FCH JU programmes and the first Call for Proposals 2022 of the Clean Hydrogen Partnership have significantly advanced both the proton-exchange membrane-based fuel cell (PEMFC) and electrolyser (PEMEL) technologies. So far, about 660 million EUR were allocated to support 122 projects addressing different aspects of PEMFC and PEMEL technologies. A large share of this funding, around 585 mil EUR supporting 102 projects, was dedicated to large scale demonstrations of PEMFC in transport and stationary applications. Largely thanks to this support, the EU reached a competitive position to provide PEMFC and PEMEL technologies with a well-established supply chain from processing the raw materials into specialised materials (e.g. electro-catalysts), production of components and sub-systems.

Significant advancements have been made in the development, validation and demonstration of PEM fuel cell technologies for material handling vehicles, buses and passenger cars as well as stationary applications. Future research and demonstration projects on PEM fuel cells are needed in transport sector such as heavy-duty vehicles, industrial vehicles, shipping and aviation.

The R&I projects on PEM electrolysers have contributed to making hydrogen production more competitive and enabled the scale-up of these technologies alongside improvements in efficiency and cost reduction. Significant progress has been made on PEMEL for example: (i) achieving a rapid response time (in the order of a few seconds) needed in grid balancing, (ii) upscale the PEM electrolysers to a multi-MW level and (iii) providing reliable green hydrogen production solutions to decarbonise industrial processes.

This paper will cover the status and main results of R&I activities in PEM fuel cells and electrolysers supported by the Clean Hydrogen Partnership, including an overview of the European competitiveness in this sector.
Load Profile Test Development and Analysis from Heavy Duty Truck Drive Cycles
Authors: Tsikonis Leonidas
Published: February 2024

On their way to their commercialisation, Fuel Cell Heavy Duty Trucks stakeholders need to demonstrate their cost effectiveness against conventional Diesel Trucks. Beyond the economies of scale of all relevant components that are employed in a Fuel Cell Electric Heavy Duty Truck, the durability of the Fuel Cell System and notably that of the Fuel Cell Stack plays an important role in the determination of a competitive cost of ownership.

A key factor for durability improvement is the understanding of the degradation mechanisms and their mitigation. Degradation, however, can be very application specific, that is, different degradation mechanisms may be prevalent in heavy duty truck applications compared to passenger cars or stationary use. This is well known to research and industry.

The European research project IMMORTAL is exactly aiming at exploring these mechanisms and their mitigation specifically for heavy duty truck application and developing and MEA that meets heavy duty requirements. Within this context, FPT Industrial, a brand of the Iveco Group, assists in defining the specific conditions met by Fuel Cell Stacks used in such powertrains.

This presentation discusses how heavy duty truck load profiles can be extracted, how they may differ and how they may be assessed before they are used to define load profile tests (LPTs). It is also discussed how the results of such testing can be used to estimate degradation trends of the Fuel Cell and subsequently its durability and the cost of ownership of fuel cell trucks.

The research leading to these results has received funding from the IMMORTAL project, which receives funding from the Fuel Cells and Hydrogen 2 Joint Undertaking (now Clean Hydrogen Partnership) under Grant Agreement No. 101006641. This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation programme, Hydrogen Europe and Hydrogen Europe Research.
(Invited) Efficient and Stable Perovskite Solar Cells Enabled By Surface Engineering with Bulky Organic Molecules
Authors: Zhu Kai
Published: February 2024

Organic-inorganic hybrid halide perovskites have attracted significant R&D attention in the photovoltaic (PV) community as a competitive technology for future PV applications. The certified efficiency of single-junction perovskite solar cell (PSC) has reached close to 26%. Using molecules/structures based on bulky organic cations (e.g., butylammonium or phenethylammonium) to improve the surface/interface properties has become a promising strategy to enhance PSC performance, including both efficiency and stability. However, significant issues still exist with the use of bulky organic molecules, such as structure control, charge transport, bulk and surface morphology, and interfacial energy alignment. In this talk, I will discuss our recent studies on surface engineering of 3D perovskites by using structures based on bulky organic molecules. The use of bulky organic molecules often results in the formation of 2D perovskite structures, which usually exhibit significant transport barriers, especially in the out-of-plane transport direction. In addition, the use of bulky organic structures can interrupt the growth of 3D perovskites. A good understanding and control of perovskite growth is critical to fully utilize the benefits associated with bulky organic molecules and related structures. I will present strategies for suppressing defect formation, improving bulk and surface morphology, and reducing transport barrier for better extraction. The physical and optoelectronic properties of perovskites can be affected by controlling the precursor chemistry and growth conditions. Some of our recent results on perovskite-based tandem devices will also be discussed. Finally, I will discuss our recent progress on selecting stability protocols to accelerate the development process of PSCs toward future commercialization.
(Invited) Role of Solvent Exchange Dynamics in the Performance of Metal Anode
Authors: Murugesan Vijay
Published: February 2024

Designing resilient and high performing batteries is a critical component in decarbonizing our economy. Facilitating the uniform and fully reversible deposition of the metal anode remains a major roadblock in realizing many battery chemistries, including multivalent batteries. The intrinsic electrolyte properties, such as the solvation phenomena of the working cation, have widely known as critical control factor to facilitate the reversible, dendrite-free, and efficient charge transfer at metal anode. However, predominant work in this field is focused on static view of solvation phenomena, such as structure and composition of first sphere solvation shell, although the solvation process is highly dynamic and driven by solvent and/or anion exchange processes driven by thermodynamic and kinetic equilibrium conditions. In this presentation, we will discuss how exchange, conformal, and re-organizational dynamics of electrolyte constituents around divalent metal cations affects the performance metrics of metal anode based batteries, namely (1) the ionic diffusivity and emerging conductivity of the bulk electrolyte; (2) the de/re-solvation processes of metal cations and emergent overpotential; and (3) the SEI evolution and emerging interfacial impedance. Through this study, we aim to generalize the strategies for designing new electrolyte systems for high-performance batteries by recognizing and regulating the critical role of solvation dynamics of working cations.
Redox-Active Polymers Designed for the Circular Economy of Energy Storage Devices
Authors: Giovannitti Alexander
Published: February 2024

The decarbonization of the transport and energy sector will accelerate the demand for electrochemical energy storage devices. While past and current research efforts strongly focused on improving the performance of cells (energy density, power density, and stability), little attention has been paid to how these devices are recycled after their end of life, leaving the recycling of devices as an afterthought. Thus, to limit the accumulation of electric waste and the depletion of important raw materials for energy storage devices, there is an urgency to develop a circular economy for materials and integrate recyclability in device architectures. In my talk, I will present a new concept where we applied chemical design strategies to intentionally develop redox-active materials for a circular economy.[1] We developed solution-processible redox-active conjugated polymers that function as binder- and additive-free electrodes with high stability in aqueous electrolytes, achieving >98% retention of the capacity after 500 charging/discharging cycles. The tuning of the local environment of the polymer further enables fast charging of micron-thick single-phase electrodes with cell voltages > 1.2 V in aqueous electrolytes. Finally, we demonstrate the recyclability of the devices, achieving >85% capacity retention after recycling (76 % retention after recycling the device twice). Our work is a demonstration of how material chemistry enables the development of a circular economy for electrochemical energy storage devices.

[1] S. T. M. Tan, T. J. Quill, M. Moser, G. LeCroy, X. Chen, Y. Wu, C. J. Takacs, A. Salleo, A. Giovannitti, ACS Energy Lett. 2021, 6, 3450.
(Invited) Ion Transport in Solid-State Electrolytes Based on TTF - TCNQ Charge-Transfer Complexes
Authors: Yang Lingyu , Schaefer Jennifer L.
Published: February 2024

Current research on solid-state organic electrolytes mainly focuses on polymer electrolytes where ion transport is facilitated by chain segmental motion. The ionic conductivity of these polymer electrolytes at room temperature in too low for many practical applications. A limited number of prior reports suggest that solid-state electrolytes including organic crystalline charge-transfer complexes can have surprisingly high ionic conductivity. We report1 that processing and environmental conditions drastically impact electron and ion charge transport properties of charge-transfer complex electrolytes based on tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) mixed with lithium bis(trifluoromethylsulfonylimide) (LiTFSI). Thermal annealing and water vapor treatment decrease electronic conductivity and increase ionic conductivity. The electrolyte with 1-1-2-0.45 molar ratio of TTF-TCNQ-LiTFSI-H2O has an ionic conductivity of 2 × 10-3 S/cm at 25 °C with electronic conductivity of order 10-7 S/cm. Thermal annealing helps reduce connectivity of the charge-transfer complexes and expose more surfaces to interact with LiTFSI, thereby decreasing electronic conductivity. Exposure of the sample to water vapor then causes a substantial increase in ionic conductivity, even when the material remains in the solid state. In this presentation, we will also report on additional experimental studies of solid-state electrolytes incorporating TTF-TCNQ.

Reference 1. L. Yang and J. L. Schaefer, “Water-Assisted Ion Conduction in Solid-State Charge-Transfer Complex Electrolytes for Lithium Batteries,” ChemRxiv, 2023. https://doi.org/10.26434/chemrxiv-2023-9k024
Chemical and Electrochemical Interaction of Halide and Sulfide-Based Electrolytes in Solid-State Batteries
Authors: Tron Artur , Molaiyan Palanivel , Paolella Andrea , Jahn Marcus
Published: February 2024

Introduction

Conventional lithium-ion batteries (LIBs) have found widespread small and large applications. However, safety issues and capacity degradation of the cells, in general, can occur due to the use of toxic and flammable liquid electrolytes [1]. As one of the next-generation LIBs, solid-state lithium batteries (SSBs) have the potential to replace liquid electrolyte LIBs due to their safety and potentially high energy density [2]. The key component of SSBs is the solid-state electrolyte (SSE). Sulfide and halide-based solid electrolytes are among the hot topics in solid electrolyte research for SSBs. Despite the advantages of solid electrolytes, such as good compatibility with high-voltage cathode materials and soft fabrication. However, the poor chemical and electrochemical stability of sulfide and halide-based solid electrolytes towards Li metal has a critical problem that causes the degradation of the lithium/solid electrolyte interface due to the formation of side reaction components that leads to inhibiting lithium kinetics [3].

Results and Discussion

Here, we have shown that a combination of halide and argyrodite (Li6PS5Cl) solid electrolytes can lead to the prevention of the formation of unfavorable interactions between solid electrolytes and lithium metal anode. The combination of halide and argyrodite (Li6PS5Cl) in the Li/Li symmetric cell can stabilize cycle life and increase the high critical current density (CCD) from C/20 to C/2 in comparison with the pure halide and argyrodite electrolytes. Furthermore, compared to the original halide and argyrodite electrolytes, a high initial coulombic efficiency and cycle life can be maintained when combined with a full Li/NCM cell. This approach to improving halide-based SSBs can provide a fairly simple and efficient strategy.

Acknowledgements

This project has received funding from the European Union's Horizon Europe programme for research and innovation under grant agreement No. 101069681 (HELENA project).

References

[1] Y. Meesala, A. Jena, H. Chang, R.-S. Liu, Recent Advancements in Li-Ion Conductors for All-Solid-State Li-Ion Batteries, ACS Energy Letters 2 (12) (2017) 2734-2751.

[2] Z. Zhang, Y. Shao, B. Lotsch, Y.-S. Hu, H. Li, J. Janek, L. F. Nazar, C.-W. Nan, J. Maier, M. Armand, L. Chen, New horizons for inorganic solid state ion conductors. Energy & Environmental Science 2018, 11, 1945-1976.

[3] C. Wang, J. Liang, J. Luo, J. Liu, X. Li, F. Zhao, R. Li, H. Huang, S. Zhao, L. Zhang, J. Wang, X. Sun, A universal wet-chemistry synthesis of solid-state halide electrolytes for all-solid-state lithium-metal batteries, Sci. Adv. 7 (2021) eabh189 1-9.
High Temperature Corrosion of Inconel 625 and Pure Nickel in Contact with Fluoride Melts
Authors: Nikbakht Aida , Bahramian Behnam , Geers Christine
Published: February 2024

Considering the fact that fossil fuels are not inexhaustible, and they pollute the environment, the automotive industry is transitioning from internal combustion to electric engines. As a result, batteries are becoming a strategic component of cars and thus battery ingredients are considered as important raw materials. Therefore, these batteries need to be recycled as well, since the natural resources for producing them are limited and some of the elements like nickel which are used in these batteries can be hazardous if left in the environment. In order to recycle electric batteries, furnaces with high temperature corrosion resistance are necessary. Maintaining these furnaces for longer periods is of great interest and necessitates it for the challenges to be dealt with, especially in case of high temperature corrosion.

In the present study, high temperature corrosion behavior of Inconel 625 is compared with pure nickel. Both metals have been exposed to fluoride melts (to mimic the recycling process) for different durations of time. The performances of these two bulk metals are investigated mainly through scanning electron microscope and X-ray diffraction. Element leaching, oxidation, depth of internal attack and depletion profile are among the main parameters studied here. Experiments are carried out both in dry and humid condition to see how humidity changes the reactions. Since there are different alloying elements in Inconel 625, and humidity is involved, pure nickel is used as the baseline to see the effect of different parameters involved. Filtered air is used as the main environment in this study and lithium fluoride is used as the main salt.
Cyclic and Isothermal Oxidation Behavior of a Directionally Solidified Ni-Al-Ti-Co-Cr Superalloy
Authors: Fazeli Tehrani Alimohammad , Farhangi Hassan , Orlov Dmytro , Pirmohammadi Mohsen
Published: February 2024

Nickel based superalloys are widely used in such applications as gas turbine blades due to their excellent mechanical properties at elevated temperatures. Oxidation is one of the life limiting factors at such temperatures since it accelerates failure mechanisms, e.g. fatigue and creep. In this project, oxidation behavior of Ni-3Al-4.8Ti-9.5Co-14Cr (wt.%) superalloy was investigated under various testing conditions. The alloy was investment-cast with preferential crystal growth direction [100]. Isothermal oxidation tests were carried out at 800°C for 150h. Cyclic oxidation tests were then conducted between 100-800°C for 150 one-hour cycles. An additional one-hour cycle was tested to replicate real-life working condition of the alloy, which consisted of heating the samples up to 800°C followed by slow cooling to 400°C. During the testing, samples were periodically taken from the furnace and weighted with an accuracy of 10-4 g to calculate the weight gain and to analyze the microstructure of formed oxide. Scanning electron microscopy (SEM) combined with energy-dispersive spectroscopy (EDS) and X-ray diffraction were used to study the microstructure of oxidation products. The results reveal that the highest amount of weight gain is obtained in isothermal testing, while the lowest in cyclic. Diffusion of Ti and Ni to the free surface results in the early-stage formation of needle-shaped oxide phases followed by severe oxidation of Cr and Al. The layer of chromium oxide is continuous while aluminum oxide is blocky at the deepest position from the free surface. Cracks form at the interface of carbide particles and gamma phase near the free surface of cyclic oxidation samples due to concentration gradient of Ni and Al. Precipitate-free zone are observed near the free surface of all the samples at the end of the tests, but internal oxidation does not occur significantly in all the samples. It is found that temperature fluctuation increases oxide spallation, which causes crack formation. At the same time, in isothermal testing, dense, crack-free layer of oxide form on the surface of superalloy.
Potential of Knudsen Effusion Mass Spectrometry (KEMS) for Energy Materials Science
Authors: Markus Torsten , Henriques D.
Published: February 2024

The determination of valuable thermodynamic data for materials at elevated temperatures is a very important issue in Materials Science. This can be achieved by the elucidation of vaporization processes with mass spectrometric techniques.

Knudsen Effusion Mass Spectrometry provides the identification of gaseous species present above condensed phases and permits the determination of their partial pressures up to a total pressure of 200 Pa.

The key for establishing model calculations using DG minimization tools like among others FactSage, Pandat or Thermocalc is the knowledge of the thermodynamic data of molecules and compounds. This includes the partial pressures of gaseous species, the standard enthalpies and entropies of formation of gaseous and condensed phases as well as their enthalpies and entropies of mixing and the knowledge of phases and chemical compounds which are formed upon reactions.

The method will be described and examples and an insight will be given how basic thermodynamic data are derived with the above mentioned method for the incorporation into thermodynamic databases. Examples of investigations carried out in our lab will be given.

The number of groups worldwide using this advanced technology has been shrinking during the last decades. Therefore, we are pleased to announce the setup of a completely new designed instrument in our laboratory which can determine data with higher precision and better resolution.

The new set up will be presented as well.
(Invited) Exploiting Organic Materials for Next Generation Batteries
Authors: Meabe Leire , Aldalur Itziar , Arrese-Igor Mikel , Boaretto Nicola , Armand Michel , Sanchez-Diez Eduardo , Martinez-Ibañez María , Ortiz-Vitoriano Nagore
Published: February 2024

Energy storage plays, undoubtedly, a fundamental role in the process of total decarbonization of the global economy that is expected to take place in the coming decades. The energy transition to a renewable and sustainable generation will be the solution to reduce greenhouse gas emissions and thus achieve the European Commission´s goal of becoming the world´s first decarbonized economy. Our mission is therefore aligned with this goal by improving the industry competitiveness and sustainable development, from a benchmark position in energy research, generating disruptive knowledge in materials and high-tech solutions. Within the electrochemical storage area, and in particular organic hybrid materials group, we work from the synthesis and design of organic molecules and polymeric materials to the understanding of their properties and interfaces with the ultimate goal of developing next generation battery systems.

In this talk, a general overview of our core research will be given with a special focus on the design of polymer electrolytes. In recent years we have explored various strategies to meet the requirements of electrolytes: high lithium cation conductivity and stability against high voltage and towards lithium metal (LiM). In this scenario we have synthesized new polymers and lithium salts. Inspired by poly(ethylene oxide), polymers containing ethylene oxide units will be presented, with decreased crystallinity to improve ionic conductivity.1 This improvement generally compromises the mechanical properties. In this respect, different strategies will be shown.2,3 However, it is difficult to design a polymer that meets all properties. In this scope, a bi-layer concept will be described and how salt migration can be addressed using a single-ion conducting polymer electrolyte (SLIC).4,5 Motivated by the bi-layer strategy, within SAFELiMOVE EU project a new solid-state-based technology have been proposed.6 The most relevant work carried out in the framework of the project will be presented.

References

I. Aldalur et al., J Power Sources, 347, 37–46 (2017).

I. Aldalur et al., J Power Sources, 448, 227424 (2020)

I. Aldalur, M. Martinez-Ibañez, M. Piszcz, H. Zhang, and M. Armand, Batter Supercaps, 1, 149–159 (2018)

M. Arrese-Igor et al., ACS Energy Lett, 7, 1473–1480 (2022)

M. Arrese-Igor et al., Energy Storage Mater, 45, 578–585 (2022)

https://safelimove.eu/
Metal Doping in 2D Co3O4 for Enhanced ORR/OER Electrocatalytic Performance
Authors: Ghufron Muhammad , Sari Fitri Nur Indah , Saputro Brahmanu Wisnu , Ting Jyh-Ming
Published: February 2024

Spinel cobalt oxide or Co3O4, has been proven to be a promising material as bifunctional electrocatalyst for ORR/OER. In this study, we show further improvement of the electrocatalytic activity via metal doping. Metal-doped Co3O4 was synthesized using a simple hydrothermal method at 120° C for 24 h, followed by calcination at 400° C for 1 h. A surfactant was used to control the morphology of the sample such that either 1D or 2D structure was obtained. The 2D structure shows better electrical conductivity with Rct of 70 Ohm vs. 86 Ohm for the 1D structure. Electrochemical test show that the 2D structure gives a ∆E of 870 mV vs. 949 mV for the 1D structure, due to primarily the excellent ORR activity of the 2D structure, i.e., E-3 = 711 mV for the 2D structure vs. E-3 = 667 mV for the 1D structure. The use of the 2D structure in zinc air battery is also demonstrated.
(Invited) Stress and Surface Engineering for Dendrites-Suppressing Solid-State Electrolytes
Authors: Ban Chunmei
Published: February 2024

This presentation will discuss a new and general paradigm via stress engineering for enabling all-solid-state batteries that use lithium or sodium (Li or Na) metal anodes. It is well known that all solid-state batteries that replace the highly flammable liquid electrolytes that are presently used will dramatically reduce the incidence of battery fires and enable using metallic anodes. Unfortunately, solid-state electrolytes (SEs) face significant technical challenges, in large part because Li dendrites readily penetrate through SEs, leading to short circuits and cell failure. Completely different from the existing approaches, which either apply high stack pressures or add a buffer layer between Li and the SEs, this approach will suppress dendrites and cracks in SEs by putting the SE surfaces into a state of residual compressive stress via ion implantation. In addition, this talk will present the understanding of surface/grain boundary science and its impact on electrochemistry, as well the future strategies to improve electrodeposition efficiency via surface and stress engineering. Combining the results from spectroscopic and structural characterization, this invited talk will highlight the impact of stress and surface engineering on reversible electrochemistry of the Garnet solid-state electrolytes and provide insights in designing all-solid-state batteries for cycling at room temperature and low stack pressure.
Elucidating the Role of Anion Groups in Lithium-Ion Diffusion
Authors: Jun KyuJung , Lee Byungju , Ceder Gerbrand
Published: February 2024

Since the 1960s, the paddlewheel effect has been proposed as a way to enhance lithium-ion diffusion in inorganic materials by using rotor-like anion groups to assist lithium-ion movement(1–5). However, so far the physical mechanism behind how anion-group dynamics affect lithium-ion diffusion has not been clearly understood. In this talk, we clearly define various types of rotational motions of anion-groups. Based on such definition, we detect and differentiate such distinct anion-group rotational motions throughout a total of 10’s of ns ab-initio molecular dynamics trajectories. By performing rigorous statistical analysis of various rotational events as well as lithium-ion diffusion events, we reveal how each type of anion rotational motions are related to lithium-ion diffusion. Our research has finally resolved the ongoing debate about the existence of the paddlewheel effect and provide a clear physical understanding of how anion-group rotations are related to fast ionic diffusion in inorganic materials.

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A. Kvist, A. Lundén, Electrical Conductivity of Solid and Molten Lithium Sulfate. Zeitschrift Für Naturforschung. 20, 235–238 (1965).

Z. Zhang, L. F. Nazar, Exploiting the paddle-wheel mechanism for the design of fast ion conductors. Nat Rev Mater, 1–17 (2022).

J. G. Smith, D. J. Siegel, Low-temperature paddlewheel effect in glassy solid electrolytes. Nat Commun. 11, 1483 (2020).

M. Jansen, Volume Effect or Paddle‐Wheel Mechanism—Fast Alkali‐Metal Ionic Conduction in Solids with Rotationally Disordered Complex Anions. Angewandte Chemie Int Ed Engl. 30, 1547–1558 (1991).
Ionic Transport in Solid Poly(trimethylene carbonate)-Li6.7Al0.3La3Zr2O12 Composite Electrolytes
Authors: Elbouazzaoui Kenza - , Nkosi Funeka , Brandell Daniel , Mindemark Jonas , Edström Kristina
Published: February 2024

Speeding up solid-state batteries commercialization requires deeper understanding of fundamentals behind the ionic transport mechanism in solid electrolytes. PEO has been widely investigated as a polymer host for both polymer and composite electrolytes. Nevertheless, there has been several confusions about its conduction mechanism being dependent on different factors. One crucial factor is the ceramic filler, garnet-type Li6.7Al0.3La3Zr2O12
"LLZO" has been considered as the most favorable ceramic material to be used for composite electrolytes thanks to its high ionic conductivity and electrochemical stability. For this work, a fully-amorphous polycarbonate-based poly(trimethylene carbonate) "PTMC" is chosen to investigate the ionic transport in a composite system composed of PTMC:LiTFSI as a polymer matrix with LLZO as an active ceramic filler according to both "ceramic-in-polymer" and "polymer-in-ceramic" approaches. The study focuses on understanding Li+-conduction depending on two properties: The ceramic particle loading and the LLZO surface chemistry. The study outputs suggest that there is an interplay between the surface chemistry and the particles loading controlling the Li-ion transport.

Figure 1
Effect of Particle Size Ratio on Microstructure and Active Material Utilization in Argyrodyte All-Solid-State Composite Cathodes
Authors: Steckermeier Dominik , Gerstenberg Jessica , Hartmann Elisa , Michalowski Peter , Kwade Arno
Published: February 2024

Among next-generation batteries, all-solid-state batteries (ASSB) promise increased energy densities, fast charging properties, and higher safety compared to traditional liquid-based systems. To achieve the demanded high energy densities high mass loadings of the composite cathodes are necessary. These consist of active material (AM), solid electrolyte (SE), and conductive additive as well as binder. Volume changes of intercalation AM and insufficient ionic percolation at low SE contents lead to an increased interfacial resistance and capacity loss. In order to promote cathode AM utilization the particle size ratio of the AM and the SE within the composite cathode needs to be optimized.

Theoretical calculations have shown that for high AM utilization at high AM loadings particle size ratio is a crucial parameter [1, 2]. Experimentally, the influence of particle size ratio has so far only been studied at laboratory scale. However, scalable process routes have not considered this important aspect. In this work, we present a solvent-based process route for the preparation of sulfide-based solid-state composite cathodes with NCM622 as AM, starting from the adjustment of the particle size of a commercially available Li6PS5Cl SE by planetary ball mill. Further process steps include the dispersion of SE with AM and conductive additive and doctor blade coating of cathode films. We analyzed the composite cathodes with regard to their internal resistance as well as their microstructure and conducted electrochemical tests in lab-scale test cells. Optimization of the particle size ratio results in an increase of AM utilization by a factor of 5 as well as an enhanced AM-SE-particle contact area and lower porosity.

References

[1] Shi T, Tu Q, Tian Y, et al. High Active Material Loading in All‐Solid‐State Battery Electrode via Particle Size Optimization. Adv. Energy Mater. 2020; 10(1): 1902881

[https://doi.org/10.1002/aenm.201902881]

[2] Bielefeld A, Weber DA, Janek J. Microstructural Modeling of Composite Cathodes for All-Solid-State Batteries. J. Phys. Chem. C 2019; 123(3): 1626–34

[https://doi.org/10.1021/acs.jpcc.8b11043]
Contribution of Anode and Cathode Potentials during Charging to the Performance of Aluminium-Ion Battery with Triethylamine-AlCl3 Electrolyte
Authors: Mukundan Charan , Drillet Jean-Francois
Published: February 2024

Aluminium ion batteries (AIBs) are a promising emerging battery technology, thanks to the high theoretical gravimetric and volumetric energy density of Aluminium as well as its very large abundancy and recycling capability.[1] In aprotic graphite-Al cell, however, practical energy density is limited by both electrochemical stability window of the electrolyte (2.4-2.6V) and specific capacity of graphite for long-term reversible storage of large AlCl4
- anions (radius 530 pm vs. 68 pm for Al3+). This works aims at studying the influence of cut-off voltage value during charging step in 1:1.5 triethylamine hydrochloride / aluminium tetrachloride (TEA:AlCl3) electrolyte on Al and graphite electrode potential under half-cell and full-cell conditions.

In Aluminium symmetric cell, potentials during Al deposition on an Al foil at 1 mA cm-2 were 60-70 mV higher in TEA-AlCl3 electrolytecompared to the cell measured with EMIMCl-AlCl3 electrolyte as reference system. Because of higher electrochemical stability of TEA-AlCl3 solution than EMIMCl-AlCl3 electrolyte, cut-off voltage of charging step in AIB full-cell was set to 2.45 V compared to 2.40 V for the reference cell. During long-term cycling at 1 A g-1, the specific capacity of the AIB cell employing TEA-AlCl3 increased from 60to 94 mAh g-1 (57%) after 1000 cycles while that of cell with EMIMCl-AlCl3 was quite constant at about 60 mAh g-1. This behaviour was explained by continuous decreasing in Al electrode potential at End-of-Charge state (EOC) during deposition reaction (charging step) in TEA-AlCl3 allowing an increase in graphite electrode potential and consequently in AIB cell capacity over the whole experiment. This increase in capacity was also accompanied by a raise of defect sites in graphite material which was revealed using Raman spectroscopy.
(Invited) Potassium-Ion Batteries
Authors: Pasta Mauro
Published: February 2024

Potassium-ion batteries (KIBs) are emerging as a promising complementary technology to lithium-ion batteries due to their potential low cost and high-rate capability [1].

In my talk, I will discuss the progress our group has made in understanding the structure-electrochemistry relationship of Prussian Blue analog cathodes [2–5]; the electrochemomechanical properties of red phosphorous (RP) [6] and their application in RP-graphite composite anodes [7] , and the transport and thermodynamic properties of K-ion electrolytes [8]. I will then highlight the critical research challenges that need to be addressed for KIBs to be commercialised[1].

References

[1] S. Dhir, S. Wheeler, I. Capone, M. Pasta, Chem
2020, 6, 2442–2460.

[2] J. Cattermull, M. Pasta, A. L. Goodwin, Materials Horizons
2021, 8, 3178–3186.

[3] J. Cattermull, K. Sada, K. Hurlbutt, S. J. Cassidy, M. Pasta, A. L. Goodwin, Chem. Mater.
2022, 34, 5000–5008.

[4] K. Hurlbutt, S. Wheeler, I. Capone, M. Pasta, Joule
2018, 2, 1950–1960.

[5] M. Fiore, S. Wheeler, K. Hurlbutt, I. Capone, J. Fawdon, R. Ruffo, M. Pasta, Chem. Mater.
2020, 32, 7653–7661.

[6] I. Capone, J. Aspinall, E. Darnbrough, Y. Zhao, T.-U. Wi, H.-W. Lee, M. Pasta, Matter
2020, 3, 2012–2028.

[7] I. Capone, J. Aspinall, H. J. Lee, A. W. Xiao, J. Ihli, M. Pasta, Materials Today Energy
2021, 21, 100840.

[8] S. Dhir, B. Jagger, A. Maguire, M. Pasta, Research Square
2022.

Figure 1