Hydrogen Polymer Electrolyte Fuel Cell Degradation Simulation In Automotive Application

Fuel cell powered vehicles usually employ a fuel cell stack plus Lithium battery hybrid power train.To develop such systems,calibrate the sizing of their components and creating the control algorithms,models are needed that perform close to the real system.One of the key issues of such models is the degradation behaviour of the fuel cell since it is very complex and depends on a vast variety of impact factors.Existing models that combine in detail chemical models with the overall vehicle simulation are unnecessarily extensive.In this thesis an existing soft-run simulation model is used and improved through including a more refined degradation model.This is done by reviewing the existing research on fuel cell degradation and voltage decay rates first and then choosing suitable values for the model.Eventually the degradation function is implemented into the model that provides degradation rates based on the single cell voltage.This should be a simple and quick tool for engineers to evaluate their system designs and energy management control algorithms.Finally an end-of-life prediction is given for the system using the voltage degradation over the course of the NEDC and including the shut-down and start-up process of the vehicle.The influences of outside temperatures,fuel purity or fuel cell operating temperature are neglected.A commonly desired lifetime above 5,000 hours is not yet reached in this thesis.