Performance comparison of mono-polar and bi-polar configurations of alkaline electrolysis stack through 3-D modelling and experimental fabrication

Abstract Generation of hydrogen using electrolysis process with integrated renewable energy sources is highly important especially in environmental aspects. In this paper, we demonstrate that the enhancement of electrolysis performance of alkaline electrolysis stacks by diminishing the distance between electrodes, while changing the properties of the Membrane Electrode Assembly (MEA). Prior to that, the performances of mono-polar and bi-polar configurations of alkaline electrolysis stack are compared through 3-D modelling and experimental fabrication. At first, two different single cell alkaline electrolysers are designed using SolidWorks as a design software and the designed cell has been fabricated using an in-house 3D printer, to avoid post machining processes. Thereafter, the best performing cell is selected by considering the performance of both designs through different experiments. Finally, the performance of the selected cell is enhanced by changing the distance between electrodes and properties of MEA. Thus, the best performing cell has been selected for the fabrication process of mono-polar and bi-polar electrolysis stacks. At last, both mono-polar and bi-polar configurations of alkaline electrolysis stacks are designed and implemented to compare the electrolysis performance of both configurations by maintaining minimum electrode distance. The results imply that the electrolysis performance of the cell can be enhanced by reducing the distance between electrodes, and the designed bi-polar stack has a better performance in terms of the efficiency, power and flow rates than the mono-polar equivalent.