The effects of the gravity on transient responses and cathode flooding in a proton exchange membrane fuel cell

The work presented in this paper includes contributions that provide insight into liquid water transport in the proton exchange membrane fuel cell (PEMFC).The purpose of the present study is to investigate the influence of gravity on the cathode flooding by accumulated liquid water at the interface between catalyst layer and gas diffusion layer (CL–GDL interface) in a PEMFC. We introduce a one-dimensional and transient model based on numerical resolution of mass transport of liquid water and oxygen in the porous GDL domain. Obtained results indicate that gravity has significant effects on the transient time and on the cell voltage at the steady regime. In this work, both opposing and aiding gravity cases, as reference to capillary actions, are considered.

► We model liquid water and oxygen transports in the porous GDL domain of a PEMFC.
► The evolution of the cell voltage is explored at fixed working current density.
► Gravity forces can not be neglected when studying the performance of a PEMFC.