Membrane Assemblies with Soft Protective Layers : Dense and Gel-Type Polybenzimidazole Membranes and Their Use in Vanadium Redox Flow Batteries
(2022) In Small 18(50).- Abstract
Polybenzimidazole (PBI) membranes show excellent chemical stability and low vanadium crossover in vanadium redox flow batteries (VRFBs), but their high resistance is challenging. This work introduces a concept, membrane assemblies of a highly selective 2 µm thin PBI membrane between two 60 µm thick highly conductive PBI gel membranes, which act as soft protective layers against external mechanical forces and astray carbon fibers from the electrode. The soft layers are produced by casting phosphoric acid solutions of commercial PBI powder into membranes and exchanging the absorbed acid into sulfuric acid. A conductivity of 565 mS cm−1 is achieved. A stability test indicates that gel mPBI and dense PBI-OO have higher stability... (More)
Polybenzimidazole (PBI) membranes show excellent chemical stability and low vanadium crossover in vanadium redox flow batteries (VRFBs), but their high resistance is challenging. This work introduces a concept, membrane assemblies of a highly selective 2 µm thin PBI membrane between two 60 µm thick highly conductive PBI gel membranes, which act as soft protective layers against external mechanical forces and astray carbon fibers from the electrode. The soft layers are produced by casting phosphoric acid solutions of commercial PBI powder into membranes and exchanging the absorbed acid into sulfuric acid. A conductivity of 565 mS cm−1 is achieved. A stability test indicates that gel mPBI and dense PBI-OO have higher stability than dense mPBI and dense py-PBI, and gel/PBI-OO/gel is successfully tested for 1070 cycles (ca. 1000 h) at 100 mA cm−2 in the VRFB. The initial energy efficiency (EE) for the first 50 cycles is 90.5 ± 0.2%, and after a power outage stabilized at 86.3 ± 0.5% for the following 500 cycles. The initial EE is one of the highest published so far, and the materials cost for a membrane assembly is 12.35 U.S. dollars at a production volume of 5000 m2, which makes these membranes very attractive for commercialization.
(Less)
- author
- Do, Xuan Huy ; Abbas, Saleem ; Ikhsan, Muhammad Mara ; Choi, Seung Young LU ; Ha, Heung Yong ; Azizi, Kobra ; Hjuler, Hans Aage and Henkensmeier, Dirk
- organization
- publishing date
- 2022
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- gel polybenzimidazole membranes, layered membrane assemblies, phosphoric acid casting, soft protective layers, vanadium redox flow batteries
- in
- Small
- volume
- 18
- issue
- 50
- article number
- 2206284
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- pmid:36319463
- scopus:85141409320
- ISSN
- 1613-6810
- DOI
- 10.1002/smll.202206284
- language
- English
- LU publication?
- yes
- id
- ddf561c8-0dac-4667-881f-9b8e030bc8f3
- date added to LUP
- 2022-12-21 08:39:05
- date last changed
- 2024-04-18 18:53:50
@article{ddf561c8-0dac-4667-881f-9b8e030bc8f3,
abstract = {{<p>Polybenzimidazole (PBI) membranes show excellent chemical stability and low vanadium crossover in vanadium redox flow batteries (VRFBs), but their high resistance is challenging. This work introduces a concept, membrane assemblies of a highly selective 2 µm thin PBI membrane between two 60 µm thick highly conductive PBI gel membranes, which act as soft protective layers against external mechanical forces and astray carbon fibers from the electrode. The soft layers are produced by casting phosphoric acid solutions of commercial PBI powder into membranes and exchanging the absorbed acid into sulfuric acid. A conductivity of 565 mS cm<sup>−1</sup> is achieved. A stability test indicates that gel mPBI and dense PBI-OO have higher stability than dense mPBI and dense py-PBI, and gel/PBI-OO/gel is successfully tested for 1070 cycles (ca. 1000 h) at 100 mA cm<sup>−2</sup> in the VRFB. The initial energy efficiency (EE) for the first 50 cycles is 90.5 ± 0.2%, and after a power outage stabilized at 86.3 ± 0.5% for the following 500 cycles. The initial EE is one of the highest published so far, and the materials cost for a membrane assembly is 12.35 U.S. dollars at a production volume of 5000 m<sup>2</sup>, which makes these membranes very attractive for commercialization.</p>}},
author = {{Do, Xuan Huy and Abbas, Saleem and Ikhsan, Muhammad Mara and Choi, Seung Young and Ha, Heung Yong and Azizi, Kobra and Hjuler, Hans Aage and Henkensmeier, Dirk}},
issn = {{1613-6810}},
keywords = {{gel polybenzimidazole membranes; layered membrane assemblies; phosphoric acid casting; soft protective layers; vanadium redox flow batteries}},
language = {{eng}},
number = {{50}},
publisher = {{John Wiley & Sons Inc.}},
series = {{Small}},
title = {{Membrane Assemblies with Soft Protective Layers : Dense and Gel-Type Polybenzimidazole Membranes and Their Use in Vanadium Redox Flow Batteries}},
url = {{http://dx.doi.org/10.1002/smll.202206284}},
doi = {{10.1002/smll.202206284}},
volume = {{18}},
year = {{2022}},
}