Mathematical modelling and performance analysis of an AEM electrolyzer

Abstract

In this study, an analytical model including electrochemical reactions and mass transfer in an anion-exchange membrane electrolyzer (AEMEL) has been developed by considering water sorption/desorption in electrodes. The model developed was used to investigate the performance of the AEMEL in terms of efficiency, transport phenomena and operating parameters. The numerical results revealed that the voltage losses in the AEMEL are mainly due to activation losses. The effects of important parameters such as membrane thickness, operating pressure on cell performance, and species transport were also investigated. The results also revealed that the AEMEL performance improves with decreasing membrane thickness, but the membrane thickness should be considered together with hydrogen permeability and differential operating pressure to operate the electrolyzer safely.

Keywords

• Anion exchange membrane
• transport phenomena
• water electrolyzer
• membrane thickness
• mathematical modelling

References

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