UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Investigation of Mass Transport Phenomena in Polymer Electrolyte Membrane Water Electrolysers

Majasan, Jude Olaoluwa; (2019) Investigation of Mass Transport Phenomena in Polymer Electrolyte Membrane Water Electrolysers. Doctoral thesis (Ph.D), UCL (University College London). Green open access

[thumbnail of Majasan_PhD Thesis_Final.pdf]
Preview
Text
Majasan_PhD Thesis_Final.pdf

Download (6MB) | Preview

Abstract

Polymer Electrolyte Membrane Water Electrolysers (PEMWEs) are considered a promising candidate for large-scale renewable energy storage and green hydrogen production. To improve efficiency and minimize cost for large-scale deployment, operation at high current densities is necessary. However, a consequence of high current density operation is increased mass transport hindrance which degrades performance. Two components are critical to mass transport in PEMWEs, namely the porous transport layer (PTL) and the flow-field plates. Both are expected to transport liquid water, product gases, electrons, and heat with minimal fluidic, thermal and voltage losses. However, the influence of morphology and configuration of both these components and operating conditions on cell performance are not well understood. This research investigates the mass transport phenomena in the PTL and in the flow-field channels in relation to performance in PEMWEs. The influence of flow-field configuration and two-phase flow characteristics in the flow channels on performance was studied by combined high-speed optical imaging and electrochemical characterization at various operating conditions. Results showed a strong correlation of performance with the flow path length and flow regime. Further, a correlative ex-situ X-ray tomography and in-situ electrochemical characterization approach was used to investigate the influence of PTL microstructural parameters such as mean pore diameter, pore size distribution, porosity, tortuosity, and porosity distribution on performance. Results indicated that minimizing contact resistance is most beneficial for improved performance over the range of current density studied. The influence of flow channel depth on performance was investigated by electrochemical impedance spectroscopy and a design of experiment (DoE) approach was employed to investigate the relative importance and interaction effects of mass transport factors on cell performance. Results showed the water feed rate and two-way interaction between the flow-field and PTL are most significant. This study provides enhanced understanding of the mass transport characteristics in PEMWEs for optimized design and improved performance.

Type: Thesis (Doctoral)
Qualification: Ph.D
Title: Investigation of Mass Transport Phenomena in Polymer Electrolyte Membrane Water Electrolysers
Event: UCL
Open access status: An open access version is available from UCL Discovery
Language: English
Additional information: Copyright © The Author 2019. Original content in this thesis is licensed under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) Licence (https://creativecommons.org/licenses/by/4.0/). Any third-party copyright material present remains the property of its respective owner(s) and is licensed under its existing terms. Access may initially be restricted at the author’s request.
UCL classification: UCL
UCL > Provost and Vice Provost Offices
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Chemical Engineering
URI: https://discovery.ucl.ac.uk/id/eprint/10084272
Downloads since deposit
112Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item