Modeling and validation of fuel cell water dynamics using neutron imaging

Using neutron imaging, the mass of liquid water within the gas diffusion layer and flow channels of an operating polymer electrolyte membrane fuel cell (PEMFC) is measured under a range of operating conditions. Between anode purge events, it is demonstrated that liquid water accumulates and is periodically removed from the anode gas channels; this event is well correlated with the dynamic cell voltage response. The estimation of flooding and cell performance is achieved by a spatially distributed (through-membrane plane), temporally-resolved, and two-phase (liquid and vapor) water model. Neutron imaging techniques have never before been applied to characterize flooding with a dead-ended anode and elucidate important issues in water management as well as provide a means for calibrating and validating a dynamic lumped parameter fuel cell model.