Workshop on Ion Exchange Membranes for Energy Applications - EMEA2019
25 – 27 June 2019 in Bad Zwischenahn (Germany)
73 participants from 17 countries made the last EMEA-workshop in June 2018 a success. The coming EMEA2019 Workshop will be the 7th workshop in this series. Material developments and ion exchange membrane based systems for energy applications will be discussed by representatives from research and industry with the focus set on anion exchange membranes and AEM based systems, like fuel cells, electrolysers and redox flow batteries.
In addition to invited and contributed talks, the workshop features a panel discussion, in which experts from academia and industry will discuss the development of the field. A poster exhibition offers scientists and especially young researchers and students the opportunity to present their work. A price for the best poster will be awarded. A guided tour through the DLR Institute of Networked Energy Systems (former NEXT ENERGY) research laboratories, coffee breaks, Lunch breaks, a get-together and a conference dinner will provide many opportunities for lively scientific exchange in a familiar atmosphere.
- David Aili (Technical University of Denmark)
- Karel Bouzek (University of Chemistry and Technology Prague, Czech Republic)
- Matthias Breitwieser (IMTEK – University of Freiburg, Germany)
- Ruiyong Chen (Saarland University, Germany)
- Hyeongrae Cho (University of Stuttgart, Germany)
- Dario Dekel (Technion/Israel Institute of Technology)
- Lorenz Gubler (Paul Scherrer Institute, Switzerland)
- Daniel Herranz (Universidad Autonoma de Madrid, Spain)
- Steven Holdcroft (Simon Fraser University, Canada)
- Patric Jannasch (Lund University, Sweden)
- Klaus-Dieter Kreuer (MPI for Solid State Research, Germany)
- Artjom Maljusch (Evonik Creavis GmbH, Germany)
- Bruno Ribeiro de Matos (IPEN Nuclear and Energy Research Institute, Brazil)
- Kenji Miyatake (University of Yamanashi, Japan)
- Miles Page (PO-CellTech, Israel)
- Jan-Justus Schmidt (Enapter srl, Italy)
- John Varcoe (University of Surrey, UK)
- Li Wang (German Aerospace Center, Germany)
- Tom Zawodzinski (UT-Knoxville and ORNL, USA)
Tuesday June 25th
18:00 | Accompanied Walk to the Train Station Bad Zwischenahn
Meeting at the Reception Desk of the Hotel Haus am Meer
18:19 | Arrival of the Hydrogen Powered Train at Platform 1
18:19 | Departure for the Ride on a Hydrogen Powered Train of ALSTOM
Accompanied by Stefan Schrank, ALSTOM, and Dr. Alexander Dyck,
DLR Institute of Networked Energy Systems
19:20 | Arrival Bad Zwischenahn, Platform 1
20:00 | Get-together
Opening speech by Stefan Schrank, ALSTOM
Wednesday June 26th
8:30 | Opening Reception Desk
9:00 | Welcome
Dr. Alexander Dyck, DLR Institute of Networked Energy Systems, Germany
9:15 | Session 1
About Performance Stability of Anion Exchange Membrane Fuel Cells
Dario R. Dekel
The Wolfson Department of Chemical Engineering
Technion – Israel Institute of Technology
(312) 340-0584 (USA)
+972 (54) 252-6370 (Israel)
A decade of intensive research work on Anion Exchange Membrane Fuel Cells (AEMFCs) has finally yielded a high cell performance that is suitable for automotive applications. This achievement is mainly a result of the successful development of new anion-exchange membranes (AEMs) with high hydroxide conductivity (100 mS cm-1 and above). Thanks to these high-performance membranes, AEMFCs with power densities higher than 1 W cm-2 and limiting current densities above 4 A cm-2 have been reached [1-2], which seemed far from possible only a couple of years ago. In spite of this remarkable progress on cell performance, it is the low performance stability during cell operation what hampers further development and implementation of AEMFCs. As it has been recently reviewed, most of the AEMFC performance stability data are still limited to <1000 h .
One of the key reasons in the reduction of cell performance is the presence of CO2. If ambient air is used instead of pure oxygen, carbonation processes occur resulting in a significant decrease in the effective anion conductivity in the AEM and, in turn, a reduction of the AEMFC power output [4-5]. While the carbonation process seems to be reversible [6-7], and so it could be mitigated, it may affect the chemical stability of the membrane, and in turn the cell performance stability . Furthermore, the hydroxide anions transported from the cathode to the anode may attack the positively charged functional groups of the polymeric membrane (and ionomer), neutralizing part of it and suppressing its anion-conducting capability. This process may actually cause irreversible performance losses during cell operation. Although cation chemistry dictates the intrinsic chemical stability of the anion-conducting ionomeric materials, it was recently shown that the hydration level at which the fuel cell operates significantly affects the chemical degradation [9-10]. This relationship between local cell hydration and ionomeric material degradation has been analyzed in modelling studies, providing further insights about the critical role of water on the performance stability . By using membranes with achievable targeted properties, the model predicts an AEMFC life-time higher than 8000 h [11-12], suitable for automotive applications.
 “Beyond 1.0 W cm-2 performance without platinum – the beginning of a new era in anion exchange membrane fuel cells”; T. J. Omasta, X. Peng, H. A. Miller, F. Vizza, L. Wang, J. R. Varcoe, D. R. Dekel, and W. E. Mustain; J. Electrochem. Soc. 165(15), J3039, 2018.
 “An optimised synthesis of high performance radiation-grafted anion-exchange membranes”; L. Q. Wang, E. Magliocca, E. L. Cunningham, W. E. Mustain, S. D. Poynton, R. Escudero-Cid, M. M. Nasef, J. Ponce-Gonzalez, R. Bance-Souahli, R. C. T. Slade, D. K. Whelligan, and J. R. Varcoe; Green Chem. 19, 831, 2017.
 “Review of cell performance in anion exchange membrane fuel cells”; D. R. Dekel; J. Power Sources 375, 158, 2018.
Polyimidazolium Ionenes as Solid Polymer Electrolytes
S. Holdcroft, T. Skalski, D. Novitski, B. Frisken, E. Shibli, W. Li, A. Wright, S. Cao, J. Fan
Department of Chemistry, Simon Fraser University, Burnaby, Greater Vancouver British Columbia, Canada
Cationic polyelectrolytes possess cationic groups that are usually tethered as a pendent functionality. In recent years, the study of cationic polymers possessing cations integral to the main chain have gained attention. However, organic-based polymer cations are prone to nucleophilic attack by hydroxide ions, destroying the anion-exchange capacity, hydroxide ion conductivity, and mechanical properties. In this presentation, we report a systematic investigation of novel arylimidazolium and bis-arylimidazolium compounds that lead to the rationale design of robust, sterically-protected poly(arylimidazolium) hydroxide anion exchange polymers that possess a combination of high ion exchange capacity and exceptional stability.
- J. Fan, S. Willdorf-Cohen, E.M. Schibli, Z. Paula, W. Li, T.J.G. Skalski, A. Tersakian Sergeenko, Hohenadel, B.J. Frisken, E. Magliocca, W.E. Mustain, C. E. Diesendruck, D.R. Dekel, S.
Holdcroft, “Poly(bis-arylimidazoliums) Possessing High Hydroxide Ion Exchange Capacity and High Alkaline Stability” Nature Comm. May 2019.
- E. Schibli, A. Wright, S. Holdcroft, B. Frisken*, “Morphology of Anion-Conducting Ionenes Investigated by X-ray Scattering and Simulation” The Journal of Physical Chemistry, Part B: Biophysical Chemistry, Biomaterials, Liquids, and Soft Matter, J. Phys. Chem. B, 122 (2018) 1730–1737.
- J. Fan, A.G. Wright, T. Weissbach, T. J. G. Skalski, J. Ward, T.J. Peckham, S. Holdcroft, Cationic Polyelectrolytes, Stable in 10 M KOHaq at 100 oC. ACS Macro Letters, 6 (2017) 1089-1093.
10:15 | Postersession with Coffee and Snacks
10:45 | Session 2
HDPE-based radiation-grafted anion-exchange membranes perform much better than LDPE-based versions in fuel cells.
Lianqin Wang,a Xiong Peng,b Marco Bellini,c Bill Mustain,b Hamish Miller,c and John Varcoea
a Department of Chemistry, University of Surrey Guildford, GU2 7XH (United Kingdom)
bDepartment of Chemical Engineering, University of South Carolina (USA)
cIstituto di Chimica dei Composti OrganoMetallici (ICCOM), CNR (Italy)
This talk will describe the latest state-of-the-art in developing radiation-grafted anion-exchange membranes (RG-AEM) and ionomer powders (RG-AEI) for use in alkaline membrane fuel cells (AEMFC). A recent finding is that the switch from using low-density polyethylene (LDPE)1 as a precursor film to using high-density polyethylene (HDPE) film2 leads to RG-AEMs that perform better in AEMFCs (better power output and in situ durability). When used in combination with partially fluorinated ETFE-based RG-AEI powders3 in the electrodes, peak power densities of 2.5 W cm-2 can be achieved in H2/O2 AEMFCs 70 – 80°C (with no gas back-pressures). Less than 8% degradation in cell voltage was achieved in a H2/air(CO2-free) AEMFC at 70°C over a 440 h constant current discharge of 600 mA cm-2 [in situ testing conducted at University of South Carolina by Mustain and Peng].2
The combination of polyethylene-based RG-AEMs and ETFE-based RG-AEI powders allows for good peak power performances when using non-precious metal cathode electrocatalysts.4 Pd-based catalysts can also be used at both the anodes [Pd-CeO2 anode catalysts supplied by Miller et al.].5
- Wang, M. Bellini, H. A. Miller, J. R. Varcoe, J. Mater. Chem. A, 6, 15404 (2018).
- Wang, X. Peng, W. E. Mustain, J. R. Varcoe, submitted (in peer review).
- L. Gonçalves Biancolli, D. Herranz, L. Wang, G. Stehlikova, R. Bance-Soualhi, J. Ponce-Gonzalez, P. Ocon, E. A. Ticianelli, D. K. Whelligan, J. R. Varcoe, E. I. Santiago, J. Mater. Chem. A, 6, 24330 (2018).
- Peng, T. J. Omasta, E. Magliocca, L. Wang, J. R. Varcoe, W. E. Mustain, Angew. Chem. Intl. Ed., 58, 1046 (2019); X. Peng, V. Kashyap, B. Ng, S. Kurungot, L. Wang, J. R. Varcoe, W. E. Mustain, Catalysts, 9, 264 (2019).
- Un-published results with Surrey’s AEMs [Pd-CeOx anodes were first reported by Miller and Dekel et in Angew. Chem. Intl. Ed., 55,6004 (2016)]. This Surrey-ICCOM collaboration is funded by Royal Society International Exchange Scheme grant IES\R3\170134.
Anion Exchange Membranes Containing Quinquephenylene Groups
Clean Energy Research Center & Fuel Cell Nanomaterials Center
4 Takeda, Kofu, Yamanashi 4008510, Japan
In the last decade, there have been a considerable effort to develop high-performance and durable anion exchange membranes (AEMs) for the applications to alkaline fuel cells, electrolyzers, and redox flow batteries. In particular, the chemical stability of AEMs in alkaline media is an issue for long-term, reliable operation of those devices. In the pursuit of chemically stable AEMs, we have recently reported some insightful results on the polymer structures. Combination of lack of heteroatom linkages such as ether, sulfide, and sulfone in the main chain and employing pendant ammonium groups contributed to the alkaline stability of AEMs. One of the typical examples is QPAF-4 copolymers composed of perfluoroalkylene/phenylene main chain and hexylammonium head groups, which exhibited high hydroxide ion conductivity (> 80 mS cm-1) and alkaline stability (> 1000 h in 1 M KOH at 80 ºC).1 For proton exchange membranes (PEMs), we recently found that quinquephenylene groups with controlled m-/p- composition functioned well in sulfonated polyphenlene to provide highly oxidative stability and good membrane forming capability.2,3 The objective of the present research is to combine the structures of QPAF-4 and SPP-QP into a single polymer (QP-QAF) for better performing AEMs and evaluate the effect of the five consecutive phenylene groups as hydrophobic component on the membrane properties.4 Synthesis and characterization of QP-QAF polymer membranes are reported.
- Ono, T. Kimura, A. Takano, K. Asazawa, J. Miyake, J. Inukai, K. Miyatake, J. Mater. Chem. A, 5, 24804−24812 (2017).
- Miyake, R. Taki, T. Mochizuki, R. Shimizu, R. Akiyama, M. Uchida, K. Miyatake, Sci. Adv., 3, eaao0476 (2017).
- Shiino, J. Miyake, K. Miyatake, Chem. Commun., 55, 7073-7076 (2019).
- Akiyama, N. Yokota, K. Miyatake, Macromolecules, 52, 2131-2138 (2019).
Selective transport of ionic species in membranes
Effects of specific interactions and nano-morphology
Max-Planck-Institute for Solid State Research Heisenbergstrasse 1, 70569 Stuttgart, Germany
Selective transport of specific ions is not only the key to certain chemical and electrochemical applications, it also raises a number of interesting fundamental questions. For example, in a redox-flow battery, a membrane has to efficiently separate the electrochemically active ionic species (e.g. the different vanadium species present in anolyte and catholyte of a VRB) while conducting other ionic species for mediating the electrochemical reactions. Fundamentally, selective transport is related to issues of ion uptake and ion mobility. There may be preferred uptake of certain ionic species while others may dominate ionic transport; under certain conditions, an anion exchange membrane (AEM) may even turn into a proton conductor.
This presentation provides insight into the effects membrane morphology and chemical interactions have on selective ion transport. Common thermodynamic considerations have been modified by including effects of ion solvation and the influence acid/base properties of the fixed ions have on counter-ion condensation. In addition, insights into the membrane’s nano-morphology allowed to identify sterical effects on ionic transport (ion-sieving) .
With these sophistications, transport data are described in a quantitative way and guidelines are provided which may help to select or tailor membranes for particular applications requiring selective ion transport.
A. Münchinger and K.D.Kreuer J. Membrane Science, submitted (2019)
K. D. Kreuer: Ion Conducting Membranes for Fuel Cells and other Electrochemical Devices
Chemistry of Materials, 25th anniversary issue 26 (1), 361–380 (2014)
12:15 | Lunch
13:45 | Guided Tour through the Laboratories of the DLR Institute Oldenburg
16:00 | Session 3
High-Performance Hydroxide Exchange Membrane Fuel Cell Stacks
Hatochen 2, Caesaria Industrial Park North, Israel
The performance demanded of Hydroxide Exchange Membrane (HEM) Fuel Cells, especially for automotive applications, has been significantly raised in the past 2-3 years, both due to impressive advances in alkaline Membrane-Electrode Assemblies (MEA’s), as well as significant improvements in proton exchange membrane fuel cell technology.
Low-resistance alkaline MEA’s, that crucially also provide very high water mobility, have recently[1,2] achieved power densities well over 2.5 W/cm2 when supplying pure O2 to the cathode of an H2-fueled, alkaline exchange membrane fuel cell. Meanwhile, careful balance of water supply to – and extraction from – the operating fuel cell was a key factor in achieving high durability, even with ionomer chemistry not specially designed for chemical stability, by assuring that cationic functional groups remain well-hydrated.
Thus the role of device water management – that is to say, control over the distribution of water throughout the membrane-electrode assembly under operation – is increasingly recognized as a key consideration, equally if not more important than isolated material properties such as catalytic activity, ion conductivity etc.
The transition away from idealized conditions to real-world device water management remains, however, a critical challenge: Replacing O2 with air (albeit CO2-free), scaling MEA’s from typically 5cm2 active area up to well over 100 cm2, maintaining effective fuel and oxygen utilization, and substituting precise mass flow controllers and humidifiers with passive humidification and the relatively imprecise flow-control of a field-deployed stack system. Water management takes center stage in all aspects of device architecture, from the nanoscale (within MEA’s) to GDLs, flow fields, stack operation parameters and control systems.
This reduction-to-practice problem has been a focus for some years at PO-CellTech, allowing us to achieve high performance in a large active-area, low-PGM hydroxide exchange membrane fuel cell stack. This talk will review the water management problem from a device perspective, as well as addressing outstanding challenges faced in readying HEM fuel cell systems for commercial mobile applications.
- Omasta, T. et al., J. Electrochem. Soc. 2018, 165, F710.
- Wang, L. et al., Energy Environ. Sci. 2019, 12, 1575.
- Marino, M.G. & Kreuer, K. D., ChemSusChem 2015, 8, 513.
- Dekel, D. R. et al., J. Power Sources 2017, 375, 351.
Enapter’s AEM electrolysers: modular, scalable onsite H2
Via di Lavoria 56G, Crespina Lorenzana (PI), Italy
Enapter (www.enapter.com) was started in 2017 with the vision of a carbon-free energy systems fuelled and powered by sustainable renewable energy sources only. In such a scenario, hydrogen as an energy carrier is key to providing independence, reliability and security for all sectors (power, heat and transport) in any energy system. We aim to provide green, affordable onsite hydrogen for any use case. That may sound ambitious, but we are approaching hydrogen electrolysis with a completely new approach than what is currently the case in the marketplace. To do this, we continue to develop our unique AEM (anion exchange membrane) technology and begin scaling our manufacturing to industry standards. We want to produce cost-efficient hydrogen generators that are environmentally friendly and recyclable.
Enapter’s unique approach can be well understood by drawing an analogy between the electrolyser industry today and the IT industry in 1980. Today’s manufacturers of large-scale electrolysers are developing systems comparable to the IT Industry’s early “Mainframes”. Each system is designed as an individual project, demanding highly sophisticated engineers and planning processes. Enapter is mimicking the introduction of the PC: a product that is small, modular and scalable. The new Enapter Electrolyser 2.0 has unique characteristics and capabilities poised to disrupt the storage and fuel markets.
Cost-efficient and easy-to-install hydrogen generators can be used by farmers, commercial enterprises or housing estates; they can be used off-grid in mini grids or in inaccessible telecommunication towers; they can supply hydrogen refuelling stations but we also sell systems to businesses that have grey hydrogen delivered in bottles for their industrial processes.
In addition to the core AEM electrolyser R&D, we focus on the development of unique and user-friendly energy management software. This enables integrators and installers to experience a simple and intuitive integration of our product into all imaginable energy system constellations. We believe that with an easy-to-install (scalable to any size) hydrogen generator in combination with plug-and-play software, we will play an important role in the widespread adoption of hydrogen energy technologies.
Polybenzimidazole-c-PVBC membranes for fuel cell and electrolyser applications
D.Herranz1, R. Coppola2, K. Ochoa1, R. Escudero1, C. Palacio3, G. C. Abuin2, P. Ocón1
1Applied Chemical-Physical Department, Universidad Autónoma de Madrid. Tomás y Valiente nº 7, 28049-Madrid, Spain. 2National Institute of Technological Industry, Av. General Paz 5445, San Martín, Buenos Aires, Argentina. 3Applied Physics Department, Universidad Autónoma de Madrid. Tomás y Valiente nº 7, 28049-Madrid, Spain.
Anion exchange polymer membranes with enhanced properties are needed for further development of alkaline fuel cells (AEMFCs) and zero-gap liquid alkaline water electrolysers (LAWEs). There are different strategies to synthesize highly stable membranes with good anionic conductivity. Based on the procedure described by Lu et al.  we have prepared series of crosslinked polybenzimidazole-c- poly vinyl benzyl chloride (PVBC) membranes with different composition and then quaternized with 1,4-Diazabicyclo[2.2.2.] octane (DABCO) to form the quaternary ammonium groups. That allowed good OH– conductivity values, higher than 20 mS cm-1. Two polybenzimidazoles have been studied: poly[2-2’-(m-fenylene)-5-5’ bibenzimidazole] (PBI) and poly(2,5-benzimidazole) (ABPBI). Both have excellent thermal and mechanical stability and the crosslinking process with PVBC forms highly stable networks. The membranes structure has been studied by IR, SEM/EDX and XPS and various properties of the membranes were determined: gel fraction, thermal stability, KOH and water uptake, swelling behavior and IEC. Degradation in alkaline and oxidative media as well as the ionic conductivity were also measured. The best membranes were tested in final application devices: For the fuel cell, a single cell with EtOH 2M/KOH 2M and pure oxygen at different temperatures and pressures was evaluated. For the electrolyser a single cell with zero gap configuration and recirculated KOH 1M at 50 ºC was studied. The obtained results are very satisfactory, in the fuel cell some membranes surpassed the peak power density of commercial PBI and in the electrolyser the ABPBI-c-PVBC 1:2 membrane showed the best performance, reaching 450 mA cm−2 at cell voltage 2 V. From the obtained results we consider these membranes are good candidates for AEMFCs and zero gap LAWEs.
- J. R. Varcoe et al., “Anion-exchange membranes in electrochemical energy systems,” Energy Environ. Sci., vol. 7, pp. 3135–3191, 2014.
- W. Lu et al., “Polybenzimidazole-crosslinked poly(vinylbenzyl chloride) with quaternary 1,4-diazabicyclo (2.2.2) octane groups as highperformance
anion exchange membrane for fuel cells,” J. Power Sources, vol. 296, pp. 204–214, 2015.
To Spanish Ministry of Economy Industry and Competitiveness (MINECO) project ENE2016-77055-C3-1-R, to Madrid Regional Research Council (CAM) project P2018/EMT-4344 (BIOTRES-CM) and the financial support from INTI (Argentina).
17:10 | Postersession with Coffee and Snacks
17:40 | Session 4
New Electrolytes for Redox Flow Batteries and Compatible PBI Anion Exchange Membrane
Ruiyong Chen,a Dirk Henkensmeierb
aTransfercenter Sustainable Electrochemistry, Saarland University
66125 Saarbrücken, Germany
bFuel Cell Research Center, Korea Institute of Science and Technology (KIST)
02792 Seoul, Korea
e-mail: firstname.lastname@example.org, email@example.com
Redox flow batteries (RFBs) are regarded as technique-of-choice for load levelling and peak shaving for the utilization of renewable energy sources, and are key component in smart grid network.[1,2] Electrolyte chemistry is a key consideration for the performance enhancement.[3-10] The conventional RFBs using non-organic redox species in aqueous H2SO4, KOH and NaCl, with limited operating voltage and volumetric energy density. Development of new high-performance electrolytes is highly important for speeding up the market penetration of RFBs. Herein, we explore the feasibility of using hydrophilic ionic liquids (such as imidazolium chloride) for tailoring the properties of electrolytes, including the electrochemical stability window of water-based electrolytes,[3,4] temperature adaptability,[5,6] solubility of redox-active organics and chemical/electrochemical stability and reversibility of active materials. Meanwhile, we report the successful application of crosslinked and methylated polybenzimidazole (PBI)-based anion exchange membranes in these systems.[2,6,8-10]
- R. Chen, ChemElectroChem 6 (2019) 603-612.
- R. Ye, D. Henkensmeier, S. J. Yoon, Z. Huang, D. K. Kim, Z. Chang, S. Kim, R. Chen, J. Electrochem. En. Conv. Stor. 15 (2018) 010801.
- R. Chen, R. Hempelmann, Electrochem. Commun. 70 (2016) 56-59.
- Y. Zhang, R. Ye, D. Henkensmeier, R. Hempelmann, R. Chen, Electrochim. Acta 263 (2018) 47-52.
- A. Tatlisu, Z. Huang, R. Chen, ChemSusChem 11 (2018) 3899-3904.
- Z. Huang, P. Zhang, X. Gao, D. Henkensmeier, S. Passerini, R. Chen, ACS Appl. Energy Mater. 2 (2019) 3773-3779.
- R. Chen, R. Ye, R. Hempelmann, S. Kim, A. Möller, J. Hartwig, N. Krawczyk, P. Geigle, Patent application: PCT/EP2018/056087, 2018.
- Z. Chang, D. Henkensmeier, R. Chen, ChemSusChem 10 (2017) 3193-3197.
- Z. Chang, D. Henkensmeier, R. Chen, J. Power Sources 418 (2019) 11-16.
- R. Chen, D. Henkensmeier, S. Kim, S. J. Yoon, T. Zinkevich, S. Indris, ACS Appl. Energy Mater. 1 (2018) 6047-6055.
An Accelerated Stress Test for Flow Battery Membranes
Lorenz Gubler1, Fabio J. Oldenburg1, Ayoub Ouarga1,2, Thomas J. Schmidt1,3
1 Electrochemistry Laboratory, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
2 academic guest from: Materials Science and Nano-Engineering Department, Mohammed VI Polytechnic University, 43150 Ben Guerir, Morocco
3 Laboratory of Physical Chemistry, ETH Zürich, 8093 Zürich, Switzerland
Vanadium redox flow batteries are well suited to provide grid-scale energy storage solutions, for instance to support power generation from wind and solar farms. The target lifetime of flow batteries is 15 to 20 years. Especially for the polymer electrolyte membrane this can pose significant challenges. Since the testing of components under target operating conditions over several years is not practical, there is a strong desire to use accelerated aging protocols to assess membrane stability. A systematic approach for this has largely been lacking in the community. An approach described in the literature is to expose the membrane to vanadium(V) solution (=VO +), the charged species in the positive electrolyte. However, the acceleration factor for degradation is modest.rium(IV) as an oxidant instead of VO +, as it has a higher oxidative strength. We performed a systematic study of ex situ membrane degradation using model radiation grafted membranes in solutions of 2 M H2SO4 containing 0.2 M Ce(IV) or V(V) in a temperature range from 30 to 80°C (Figure 1). The correlation to the stability measured in situ is presented and discussed. Prospects of using this method for screening the stability of membranes for the use in vanadium redox flow batteries are discussed and limitations highlighted.
18:20 | Break
19:00 | Conference Dinner
Thursday June 27th
9:00 | Session 5
Anion Conducting Membranes for Water Electrolysis: Translating ex-situ Properties into in-situ Performance
Dr. Artjom Maljusch, Patrick Borowski, Oliver Conradi
Evonik Creavis GmbH
Paul-Baumann-Str. 1, 45772 Marl, Germany
With the transformation from fossil-based energy generation to renewables, electrolytic hydrogen will play a key role. One limiting factor to widespread adoption of electrolysis for hydrogen production and energy storage are high specific investment costs of PEM-based systems. However, membrane electrolysis under alkaline operation enables elimination of expensive components while keeping many operational advantages of PEM systems. Even though the research efforts on OH- ion- conducting polymers and membranes have been increased significantly in recent years there is still no concept with commercial maturity available.
This presentation will provide an overview of some generic design rules & performance indicators which are important for development of high performing anion conducting membranes as well it will give some hints how to translate intrinsic membrane properties into reasonable in-situ performance. This holistic approach can provide a guideline for both academics and industry to better synchronize materials development with system requirements and vice versa. Additionally, it will reveal first insights into the development progress in the field of anion conducting membranes done by Evonik over last few years.
Aryl ether-free hydroxide ion exchange membranes carrying alicyclic quaternary ammonium cations
Thanh Huong Pham, Joel S. Olsson, Andrit Allushi and Patric Jannasch
Department of Chemistry, Lund University
P.O. Box 124, SE-22100 Lund
Considerable research efforts are now made to synthesize and characterize durable hydroxide exchange membranes (HEMs) with the ultimate aim to develop efficient and environmentally benign alkaline fuel cells and electrolyzers . A central challenge is to identify and synthesize polymeric HEM materials that possess the required thermochemical and mechanical stability. Previous studies have shown that some aliphatic mono- and bicyclic quaternary ammonium (QA) cations possess a very high alkaline stability . At the same time, aryl ether-free aromatic polymer backbones have emerged as very stable under alkaline conditions .
We have recently reported on the preparation and properties of poly(arylene piperidinium)s as a new class of high-performance HEMs directly accessible from commercially available and quite inexpensive starting materials . In an extension of this work, corresponding HEMs functionalized with spirocyclic cations through cyclo-quaternizations were also studied . In order to systematically investigate the influence of polymer and alicyclic cation structure on, e.g., the hydroxide conductivity and alkaline stability, we have studied a series of terphenyl-based polymers functionalized with dimethylpiperidinium and spirocyclic 6-azonia-spiro[5,5]undecane-6-ium cations, respectively (Scheme 1). The results demonstrated that the type of cation, its position in the polymer structure and the configuration of the backbone terphenyl units (para or meta) had a profound influence on HEM properties. In the current presentation we will discuss molecular design principles, synthetic procedures and important structure-property relationships of aryl ether-free hydroxide ion exchange polymers and membranes functionalized with alicyclic quaternary ammonium cations.
- M. A. Hickner, Electrochem. Soc. Interface 26 (2017) 69–73.
- M. G. Marino, K. D. Kreuer, ChemSusChem 8 (2015) 513–523. E. J. Park, Y. S. Kim, J. Mater Chem. A 6 (2018) 15456–15477.
- J. S. Olsson, T. H. Pham, P. Jannasch, Adv. Funct. Mater. 28 (2018) 1702758.
- T. H. Pham, J. S. Olsson, P. Jannasch, J. Mater Chem. A 6 (2018) 16537–16547.
Electrochemical Applications of Alkaline Membranes
Thomas Zawodzinski1, Shane Foister1, Reed Wittman1, Ming Qi2, Alan Pezeshki2, Asa Roy1,2 and Gabriel Goenaga1
1University of Tennessee-Knoxville and Oak Ridge National Laboratory
1512 Middle Drive, Knoxville, TN 37996
2Peroxygen Systems Inc.
We have developed a membrane material consisting of a cross-linked PPO-based polymer functionalized with anion exchange groups and loaded with KOH or NaOH. We have scaled these materials up by a roll-to-roll coating and are using them in several applications. The membranes, which are best considered to be hydrated gels, can be highly conductive, seem to be unaffected by CO2 and exhibit reasonable stability over the course of several months at 60oC. In this talk we will introduce several applications of the membranes in alkaline electrochemical cells.
We have used these membranes in a number of studies. Several years ago, we discovered a catalyst that allows reversible oxygen reduction selectively via a 2e– process, i.e. to peroxide. The first discovery was carried out on a rotating disk electrode and involved the adsorption of an active compound. After significant effort, we successfully synthesized a high surface area analogue of this catalyst. We then transitioned this catalyst into a membrane electrode assembly and demonstrated reversible cycling of the oxygen electrode in symmetric cells, with oxygen evolution occurring at or below 1V with ~95% unidirectional efficiency. We applied this approach to the production of peroxide and to Zn-peroxide batteries and are in the process of developing a high efficiency reversible fuel cell system for long-term energy storage.
10:30 | Postersession with Coffee and Snacks
11:00 | Panel Discussion
Dr. Alexander Dyck (DLR Institute of Networked Energy Systems, Germany)
Prof. Dario Dekel, Technion – Israel Institute of Technology, Israel
Jan-Justus Schmidt, Enapter, Italy
Dr. Miles Page, PO-CellTech, Israel
Dr. Tom Zawodzinski, UT-Knoxville and ORNL, USA
12:15 | Lunch
13:45 | Session 6
High performing and economic platinum group metal free anode catalysts for AEM electrolysers – Opportunities and Challenges
Li Wanga, Marta P. Panaderob, Simon Geigera, Seyed S. Hosseinya, Aldo S. Gagoa, Hermenegildo Garciab and K. Andreas Friedricha,c
aInstitute of Engineering Thermodynamics, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569 Stuttgart, Germany
bInstituto mixto de tecnología química (CSIC-UPV), Universitat Politècnica de València, , 46022 Valencia, Spain
cUniversity of Stuttgart, Institute of Building Energetics, Thermal Engineering and Energy Storage (IGTE), Pfaffenwaldring 31, 70569 Stuttgart, Germany
e-mail of corresponding author: firstname.lastname@example.org
Global warming associated with anthropogenic emissions of CO2 caused by the use of fossil fuels as energy carriers has become a severe problem for the modern society. To mitigate this issue, alternative sources of energy carrier have to be evaluated and implemented into our everyday life. One promising and ubiquitous energy carrier is hydrogen, which can be generated by splitting water via water electrolysis. This technology is not only an excellent way to create hydrogen but can also be modified to create other fuels or valuable chemicals such as ammonia and methanol from nitrogen and carbon dioxide, respectively . Yet although electrolysis has a great potential to be the technology for a greener future the challenges to be overcome certainly dampen the optimism and prevent its breakthrough as the leading technology for a more sustainable and green energy economy. One of the major drawbacks of the electrolysis technology is the high energy consumption to split the water at the anode side for the oxygen evolution reaction (OER), for which platinum group metals (PGM) are employed to mitigate this circumstance . The use of PGMs as OER enhancing catalysts in electrolysis however, especially in the polymer exchange membrane (PEM) electrolysis is, if not the major but one of the flaws of the technology. This can be mitigated by employing a slightly other approach in the upcoming sibling technology, the anion exchange membrane (AEM) electrolysis. Yet, the stability and performance  of the catalysts to drive the OER in the AEM electrolysis are as much as a drawback as using PGMs in the PEM electrolysis. The present work is devoted to developing PGM free and high performing OER catalysts for AEM electrolysis.
In this talk, the layered double hydroxide (LDH) NiFe and NiMn were developed and evaluated via various electrochemical characterization techniques in a lab scale AEM electrolyser under realistic conditions. We will discuss electrochemical characterisation results of these materials and their performances as OER catalyst in AEM electrolyzer and discuss the difference between realistic testing conditions and techniques which are less suited for evaluating the performance of catalysts in real electrolysis systems. In addition various physical analysis methods such as SEM, EDX, BET, XPS, TEM, and ICP-MS were employed to deepen our understanding of the reaction and aging mechanism of the OER catalysts, which will be also discussed.
- A. Olah, G. K. Surya Prakash and A. Goeppert, J. Am. Chem. Soc., 2011, 133, 12881-12898.
- Wang, V. A. Saveleva, S. Zafeiratos, et al., Nano Energy, 2017, 34, 385-391.
- Fabbri, M. Nachtegaal, T. Binninger, et al., Nature Materials, 2017, 16, 925-931.
Ion-solvating membranes for high-rate alkaline water electrolysis
David Aili, Mikkel Rykær Kraglund, Joe Tavacoli, Christodoulos Chatzichristodoulou and Jens Oluf Jensen
Technical University of Denmark, Department of Energy Conversion and Storage,
Elektrovej 375, 2800 Lyngby, Denmark
Water electrolyzers constructed based on alkaline ion-solvating membranes in combination with non-noble electrodes support hydrogen generation at high current densities without compromising energy efficiency.1 The high conductivity of electrolyte systems based on polybenzimidazole membranes in 20-25 wt.% aqueous KOH at 20-80 °C allows for excellent cell performance, but improving the long term stability remains a challenge.2, 3
In this contribution, blends of polysulfone (PSU) and poly(vinylpyrrolidone) (PVP) are explored as ion- solvating polymer electrolyte membrane systems in alkaline water electrolysis. Transparent and homogeneous membranes were obtained in the full composition range. Increasing the PVP content in the blend drastically increased electrolyte uptake, and at PVP contents higher than 45 wt.% the membrane showed ion conductivity in a technologically relevant range of 10-100 mS cm-1 or even higher in 20 wt.% aqueous KOH. The membrane system was extensively characterized throughout the full composition range and the down-selected membrane composed of 25% PSU and 75% PVP was employed in a single cell lab-scale water electrolyzer, showing excellent performance and stability during the course of one week at 500 mA cm-2 at 60 °C in 20 wt.% KOH.
- M.R. Kraglund, M. Carmo, G. Schiller, D. Aili, E. Christensen, J.O. Jensen, 2019, Submitted.
- M.R. Kraglund, D. Aili, K. Jankova, E. Christensen, Q. Li, J.O. Jensen, J. Electrochem. Soc. 2016, 163, F3125-F3131.
- D. Aili, A.G. Wright, M.R. Kraglund, K. Jankova, S. Holdcroft, J.O. Jensen, J. Mater. Chem. A 2017, 5, 5055-5066.
Progress in development of alkaline water electrolysis stack based on “zero-gap” approach
Karel Bouzek, Jaromír Hnát, Martin Paidar, Karel Denk, Michaela Plevová, Roman Kodým and Jan Žitka
University of Chemistry and Technology, Prague Technická 5, 166 28 Prague 6, Czech Republic
Traditional approach to design of the industrial scale alkaline water electrolysis cells and stacks is based on utilization of porous separators of the anode and cathode compartments. Main role of the separator is to prevent mixing of the produced gases and thus to (i) avoid formation of explosive mixture of hydrogen and oxygen and (ii) minimize faradayic efficiency losses. Utilisation of this type of separator has severe impact on the design of the cell and corresponding operational conditions. This concerns mainly significant distance between electrodes and separator, utilization of the concentrated KOH as an electrolyte solution and necessity to keep equal pressure in both electrode compartments.
Within the last years significant advancement was reached in development of the new anion selective polymer electrolytes. The modern materials show nowadays satisfactory performance under certain conditions, especially at operational temperature lower than 50 °C. Novel polymer electrolytes partly reported during previous EMEA meetings also allow to fix efficiently catalytic layer not only on top of the electrode surface (CCE), but also directly on the surface of the membrane (CCM). Utilizing membranes based on these polymers allows designing electrolysis cell based on the so-called zero gap approach, i.e. with the electrodes attached directly to the membrane surface.
Present contribution reports on development of two generations of the laboratory scale alkaline water electrolysis stack together with its selected components. Strategies for operating the stack in mode with zero pressure gradient on the membrane are discussed as well. The experimental study was accompanied by mathematical modelling on different levels of complexity representing solid background for the future stack scaling up.
The financial support of this research received from the Ministry of Industry and Trade of the Czech Republic under project No. FV10529 is gratefully acknowledged.
Anion Exchange Blend Membranes for Vanadium Redox Flow Battery Applications
Hyeongrae Cho1, Vladimir Atanasov 1, Henning M Krieg2 and Jochen A Kerres1, 2
1 Institute of Chemical Process Engineering, University of Stuttgart, 70199 Stuttgart, Germany
2 Faculty of Natural Science, North-West University, Focus Area: Chemical Resource Beneficiation, Potchefstroom 2520, South Africa
To be applied in Vanadium Redox Flow Batteries (VRFBs), Anion Exchange Blend Membranes (AEBMs) were prepared and characterized. Bromomethylated poly(2,6-dimethyl-1,4-phenylene oxide) (Br-PPO), poly[(1-(4,4’-diphenylether)- 5-oxybenzimidazole)-benzimidazole] (PBI-OO) and sulfonated polyether sulfone polymer were combined to prepare 3-component AEBMs with 1,2,4,5- tetramethylimidazole (TMIm) used for quaternization. The compositions of the anion-exchange polymers in 3-component AEBMs were systematically varied for optimization of the AEBMs to be applied in VRFBs. While the 3-component AEBMs showed comparable efficiencies with a Nafion® 212 membrane, it displayed improved vanadium ions cross-over confirmed by open circuit voltage tests and capacity fade tests conducted in VRFBs. 
Furthermore, 3-component AEMBs were prepared using different combinations of blend polymers. A Br-PPO as an anion exchange precursor polymer, two polybenzimidazoles (non-fluorinated PBI-OO or partially-fluorinated F6-PBI) as a matrix polymer, two sulfonated polymers (a partially-fluorinated polyether or non-fluorinated poly(ethersulfone)) and TMIm as a tertiary amine for quaternization were used for AEMBs preparation. One of the blend membranes based on fluorinated polymers showed improved performance, compared to that of non-fluorinated blend membranes. 
A novel anion exchange polymer was synthesized via a 3 steps process based on poly(pentafluorostyrene) (PPFSt). First, 1-(2-dimethylaminoethyl)-5-mercaptotetrazole was grafted onto PPFSt by nucleophilic F/S exchange. In the second step, tertiary amino groups were quaternized with iodomethane to provide anion exchange sites. Finally, the synthesized polymer was blended with F6-PBI so that it could be applied in VRFB. The blend membranes exhibited better single cell battery performance in terms of efficiencies, open circuit voltage test and charge-discharge cycling test, compared to that of a Nafion® 212 membrane. 
- H. Cho, H. M Krieg, J. A Kerres, Membranes 2018, 8(2), 33
- H. Cho, H. M Krieg, J. A Kerres, Membranes 2019, 9(2), 31
- H. Cho, V. Atanasov, H. M Krieg, J. A Kerres, Materials, Submitted
15:15 | Postersession with Coffee and Snacks
15:45 | Session 7
Identification of the Polymer and Electrode Polarizations of Nafion Dielectric Spectrum
R. Matos1, J. S. da Silva1, U. Schade2, L. Puskar2, F. C. Fonseca1
1 Instituto de Pesquisas Energéticas e Nucleares – IPEN-CNEN/SP, São Paulo, SP, 05508000, Brasil
2 Methods for Material Development, Helmholtz-Zentrum für Materialien und Energie GmbH , Berlin, 12489, Germany
In order to understand the dynamic properties of amorphous ionic solids, which are related to ion motion as well as to network motion, it is important to study such materials over a wide range of frequencies . The dielectric spectroscopy (DS) measurements cover the frequency range (~10-2-107 Hz range) that is not available by most traditional techniques and the behavior of the observed dielectric dispersions provides a method for directly probing the polarization of ions along the a broad range of length scales in amorphous materials . The main aspects of the polymer relaxations at the fundamental level are needed for the advancement of the ionomer technology. In this context, ideally both the dynamics of electrode polarization, ion-hopping and polymer relaxations should be identified. However, the ion-hopping and polymer relaxations characteristic frequencies are commonly overlapped with electrode polarization, hindering the investigation of the dynamics of the dielectric dispersions observed in Nafion spectrum . For around 40 years the origins of the α- and β-relaxations in Nafion have been in debate [3,4,5]. In this work, a comprehensive set of DS data of Nafion membranes and solutions in a broad range of temperature, relative humidity and frequency were analyzed in different spectral representations in order to pinpoint the frequency ranges of the dielectric relaxations, ion-hopping and the electrode polarization. In addition, the separation of the electrode from the polymer polarizations was obtained by testing different variables, namely: i) different membrane thickness; ii) distinct electrode materials and area; and iii) in-plane and through-plane DS configurations. Such characterizations were confronted with small angle-X-ray scattering (SAXS), dynamic mechanical analysis (DMA) and infrared spectroscopy (FTIR). Such techniques contributed for the determination of the nature of the each relaxation process of Nafion’s dielectric spectra advancing the understanding the relationship between the ionic network and proton conductivity, which is crucial for tailoring new high-performance ionomers.
- A. Kusoglu, A. Z. Weber, Chem. Rev. 2017, 117, 987-1104.
- Schönhals, A.; Kremer, F. in Broadband Dielectric Spectroscopy. F. Kremer, A. Schönhals, Editors, p. 59, Springer Verlag, Berlin (2003).
- Osborn, S. J.; Hassan, M. K.; Divoux, G. M.; Rhoades, D. W.; Mauritz, K. A.; Moore, R. B. Macromolecules, 2007, 40, 3886.
- V. Di Noto, E. Negro, J-Y. Sanchez, C. Iojoiu, J. Am. Chem. Soc., 132, 2183 (2010).
- Matos, B. R.; Goulart, C. A.; Santiago, E. I.; Muccillo, R.; Fonseca, F. C. Appl. Phys. Lett., 2014, 109, 091904.
Confocal Raman microscopy as non-destructive tool to resolve structure and properties in ionomer composite membranes
S. Vierratha,b, T. Böhma, B. Shanahana, M. S. Mu’mina, P. Veha, B. Brittonc, S. Holdcroftc and M. Breitwiesera,b
a Laboratory for MEMS Applications, IMTEK Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg, Germany
b Hahn-Schickard Gesellschaft für angewandte Forschung e.V., Georges-Koehler-Allee 103, 79110 Freiburg, Germany
c Department of Chemistry, Simon Fraser University, Burnaby, Canada
The structure and properties of ionomer composite membranes are the key for the performance and stability of various electrochemical energy applications. Confocal Raman microscopy is an established tool for the investigation of polymers. However, this technology was so far only applied scarcely in the field of electrochemical energy applications. In this work, we report an in-depth study of ionomer equivalent weight quantification in fuel cell membranes during accelerated stress testing as well as the chemical 2D imaging of a typical Nafion composite membrane (Nafion XL), shown in the left Figure . In addition, the local hydration in the surrounding of single nanofibers embedded in Nafion ionomer was resolved by a confocal Raman microscope: in the middle Figure, a confocal through- plane image through a single PVDF-HFP/PVP nanofiber embedded in Nafion is shown . In comparison to the surrounding Nafion, the water uptake in the hydrophilic fiber is locally increased. As a third example, an anion exchange membrane (AEM) for vanadium redox flow batteries based on HMT-PMBI  was investigated with Raman. The employed AEM substantially reduced vanadium crossover and thus improved the coulombic efficiency (CE) compared to Nafion XL (right Figure). The AEM proved to be stable over the test, and Raman spectroscopy was employed to investigate possible chemical changes of the ionomer structure upon an accelerated degradation test .
- T. Böhm, R. Moroni, M. Breitwieser, S. Thiele, S. Vierrath, J. Electrochem. Soc. 166 (2019) F3044-F3051.
- M.S, Mu’min, T. Böhm, R. Moroni, R. Zengerle, S. Thiele, S. Vierrath, M. Breitwieser, J Memb Sci, (submitted)
- A.G. Wright, J. Fan, B. Britton, T. Weissbach, H.-F. Lee, E.A. Kitching, T.J. Peckham, S. Holdcroft, Energy Environ. Sci. 9 (2016) 2130–2142.
- B. Shanahan, T. Böhm, B. Britton, S. Holdcroft, R. Zengerle, S. Vierrath, S. Thiele and M. Breitwieser, Electrochemsitry Comm. (2019)
16:25 | Closing Words
17:30 | Sightseeing
Call for Papers
Participants are invited to submit abstracts for contributed talks until March 31st 2019 and for poster presentations not later than May 5th 2019 to email@example.com. Please use the provided template. A confirmation if the abstract has been accepted and whether it will be an oral or poster presentation at the EMEA2019 workshop will be issued after May 5th. A price will be granted for the best poster.
Dr Alexander Dyck – DLR Institute of Networked Energy Systems (Germany)
Prof Dirk Henkensmeier – Korea Institute of Science and Technology (KIST, South Korea)
Prof Artur Michalak – Jagiellonian University in Krakow (Poland)
The participation fee of €395 is payable after receipt of invoice. For registration please complete the “Workshop Registration Form” and submit it by fax or email to DLR Institute of Networked Energy Systems by June 1st 2019.
Because the number of participants is limited to 75, registrations are considered in order of receipt.
DLR Institute of Networked Energy Systems
Carl-von-Ossietzky-Str. 15 | 26129 Oldenburg | Germany
Phone: +49 441 99906-362
Fax: +49 441 99906-109
The spa town Bad Zwischenahn is located in the north-west of Germany and is a famous recreational area because of its colorful flowering rhododendron shrubs and park-like landscape. The city can be reached conveniently by train or by car. Airports are Amsterdam, Bremen and Hamburg, the nearest airport is Bremen Airport.
The Workshop will be held at the conference and golfing hotel “Hansens Haus am Meer“, which is located directly in the spa gardens at the lake “Zwischenahner Meer”, the third largest lake in Lower Saxony.
Bad Zwischenahn has a range of hotels in a variety of price categories. Rooms can also be booked at the conference hotel „Hansens Haus am Meer“.
If you are interested in booking a room in the conference hotel for your overnight stay in Bad Zwischenahn, you can do so by writing an email directly to the hotel (firstname.lastname@example.org). Rooms are 99.00 € per night. Please refer to the workshop when booking.
The nearest international airport is Bremen, which is 60 km from Bad Zwischenahn.
Bad Zwischenahn has a train station that is served by trains from the rail transport providers “Deutsche Bahn” (www.bahn.de) and “Regio-S-Bahn” (www.regiosbahn.de).
The “Hansens Haus am Meer” hotel offers a free shuttle service from the train station to the hotel on request.
Coming from Bremen (A28):
Follow the A28 autobahn in the directions for Oldenburg / Emden / Leer. In Oldenburg, at the interchange “Oldenburg West“ continue to Emden / Leer on the A28. Leave the autobahn at the exit ramp No. 9 “Neuenkruge” and follow the road signposts to Bad Zwischenahn.
Coming from Leer / Netherlands (A31):
Change to the A31 autobahn at the “Leer” junction and follow the A28 in the direction for Oldenburg. Leave the autobahn at the exit ramp No. 8 “Zwischenahner Meer” and follow the road signs to Bad Zwischenahn.
The conference fee of €395 includes the lab tour, lunch and coffee breaks on both days as well as the get-together on Tuesday evening and the conference dinner on Wednesday evening and the VAT. Also covered is the bus tour to the DLR Institute of Networked Energy Systems.
DLR Institute of Networked Energy Systems may charge an administration fee of EUR 70.00 for any change or cancellation of registration. Cancellation must be received by DLR Institute of Networked Energy Systems in writing up until seven days prior to the event. Cancellations received after this date will be charged the full fee.
The program is subject to amendment. In the unlikely event of it being cancelled, registration fees already paid will be refunded.
If you have any further questions, please do not hesitate to contact us.
Phone: +49 441 99906-362