Multiphase flow in PEM water electrolyzers: a mini-review

In comparison to alternative water electrolysis technologies, polymer electrolyte membrane water electrolysis (PEMWE) has several advantages, such as high-voltage efficiency, pure gas production, short response time, and the capability to operate under high pressure and current density. A thorough comprehension of the multiphase flow characteristics within the porous transport layer (PTL) and flow channels is vital to enhance the efficiency of PEMWE. This paper presents an overview of current knowledge on multiphase flow in PEMWE and relevant modeling methods, highlighting the significance of regulating the microstructure of PTL and distinguishing the effects of multiphase flow in the flow channel from those in PTL. Moreover, to simulate PEMWE accurately, it is crucial to consider comprehensive physical and electrochemical processes and develop dependable closure models.