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Elestor’s CEO Guido Dalessi to depart by year-end
Guido Dalessi, chief executive officer (CEO) of Dutch long-duration electricity storage company Elestor, will step down from his role as CEO at the end of 2024. “I am leaving Elestor in the knowledge that the company I helped create is in safe hands. I will stay on as shareholder but will hand over the reins to my colleague Hylke van Bennekom, then maximise my contribution to the energy transition as a non-executive supervisory board member and active advisor to small and large companies.”
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Between hydrogen pipelines and electrolyzers
"Flow batteries are considered one of the most economical options for long-duration energy storage. In an interview with Guido Dalessi, CEO of Elestor, we will find out how the Dutch company uses innovative technologies to benefit from the synergy of electricity and hydrogen for its flow batteries."
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One year since winning Offshore Wind Innovators Awards
Elestor covered by TKI Offshore Energy: "How's Elestor faring, one year after winning both the Offshore Wind Innovators Jury and Audience Awards? We have a look at the innovators of renewable energy storage and the progress they made. Elestor offers an important element for a successful energy transition."
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Sustainable Electrical Energy Centre of Expertise
Join Elestor CEO Guido Dalessi’s exploration of the power of innovative technologies.
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ReCharge Earth, Conference & Expo
See Elestor’s exhibit and hear our CEO Guido Dalessi explain the link between innovation and growth.
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Wind Energy Technology Summit
Hear from Elestor during day two: Production of green electrons & molecules at sea.
Read moreLong-term performance of hydrogen-bromine flow batteries using single-layered and multi-layered wire-electrospun SPEEK/PFSA/PVDF membranes
Sanaz Abbasiab, Yohanes Antonius Hugob, Zandrie Bornemanac, Wiebrand Koutb and Kitty Nijmeijer*ac
aMembrane Materials and Processes, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands. E-mail: D.C.Nijmijer@tue.nl
bElestor BV P.O. Box 882, 6800 AW Arnhem, The Netherlands
cDutch Institute for Fundamental Energy Research (DIFFER), P.O. Box 6336, 5600 HH Eindhoven, The Netherlands
Abstract
Sulfonated poly (ether ketone) (SPEEK), perfluorosulfonic acid (PFSA), and polyvinylidene fluoride (PVDF) were wire-electrospun. Subsequently, multiple electrospun layers in different arrangements were hot-pressed into sustainable membranes for use in hydrogen-bromine flow batteries (HBFBs). The relationship between the electrospun layer composition and arrangement, membrane properties, and battery performance was explored. Wire-electrospinning and hot-pressing improved SPEEK and PFSA/PVDF compatibility, yielding dense membranes. Higher SPEEK contents lead to rougher morphologies, while the insulating nature of PVDF decreases the ion exchange capacity (IEC) and HBr uptake compared to commercial PFSA. The multi-layer assembly negatively impacted the membrane transport properties compared to the single-layer arrangement. Although wire-electrospinning improves the polymer dispersion and fixed charge density, SPEEK-rich regions of the blend membranes lack the high selectivity of PFSA, thus reducing the ionic conductivity. This is especially clear in the multi-layer membranes with accumulated SPEEK in the intermediate layer in the through-plane direction. Following initial property comparisons, thinner wire-electrospun SPEEK membranes were prepared with area resistance in the PFSA-comparable range. Among the wire-electrospun SPEEK/PFSA/PVDF membranes, the single-layered membrane with 8 wt% SPEEK (SPF1-8; 62 μm) displayed stable HBFB performance at 200 mA cm−2 over 100 cycles (64 cm2 active area). Based on the ex-situ measurements and cell performance results, a total of ∼10.5 wt% SPEEK is suggested as the limit for both single and multi-layered wire-electrospun membranes, combined with a maximum membrane thickness of ∼50 μm. This ensures robust HBFB performance, positioning wire-electrospun SPEEK/PFSA/PVDF membranes as a PFSA alternative in energy storage.
Wire based electrospun composite short side chain perfluorosulfonic acid/ polyvinylidene fluoride membranes for hydrogen-bromine flow batteries
Yohanes Antonius Hugo a, b, Wiebrand Kout b, Antoni Forner-Cuenca a, Zandrie Borneman a, c, Kitty Nijmeijer a, c, *
a Membrane Materials and Processes, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, PO Box 513, 5600MB Eindhoven, the Netherlands
b Elestor B.V., 6827 AV Arnhem, the Netherlands
c Dutch Institute for Fundamental Energy Research (DIFFER), P.O. Box 6336, 5600 HH Eindhoven, the Netherlands
⁎ Corresponding author. E-mail address: d.c.nijmeijer@tue.nl (K. Nijmeijer).
Abstract
A main component of a hydrogen-bromine flow battery (HBFB) is the ion exchange membrane. Available membranes have a trade-off between the major requirements: high proton conductivity, low bromine species crossover, and high mechanical and chemical stability. To overcome this, electrospinning of a highly proton conductive polymer (short side chain perfluorosulfonic acid (SSC PFSA)) and a hydrophobic inert polymer (polyvinylidene fluoride (PVDF)) was used to electrospin composite polymer fiber mats. Piles of multiple mats were hot pressed resulting in dense ion exchange membranes. Membranes with three different SSC PFSA/PVDF ratios were prepared, characterized, and subjected to short and long term (1500 h) HBFB testing. The electrospun membranes have performances very comparable to those of commercial membranes. For the SSC PFSA/PVDF electrospun membrane, a higher SSC PFSA loading gives a higher membrane proton conductivity compared to a lower loading, but at the expense of a higher bromine species crossover. The SSC PFSA/PVDF (50/50 wt%) membrane shows a coulombic efficiency of 98%, a voltaic efficiency of 80% and an initial available capacity of 105 Ah L− 1 at a current density of 150 mA cm− 2, which equals that of the current benchmark long side chain PFSA membrane. This performance is constant over 200 cycles during 2 months of continuous HBFB operation.
High selectivity-conductivity reinforced perfluorosulfonic acid membranes for hydrogen-bromine flow batteries.
Yohanes Hugo1, 2, Wiebrand Kout1, Friso Sikkema1, Zandrie Borneman2, Kitty Nijmeijer2
1Elestor B.V., 6812 AR Arnhem, the Netherlands
2Membrane Materials and Processes, Eindhoven University of Technology, Department of Chemical Engineering and Chemistry, PO box 513, 5600 MB Eindhoven, The Netherlands
Abstract
Reinforced proton exchange membrane (PEM) were developed to increase the mechanical strength of thin membranes (≤30 µm) for PEM fuel cell applications. In hydrogen-bromine flow batteries (HBFBs), Br2 and Br– crossover through the membrane may affect the lifetime of HBFBs as a result of dissolution or passivation of the platinum catalyst. One study suggested that the reinforcement reduces the bulk Br2 and Br– transport and x-y (in-plane) swelling [1].