PROGNOSEMODEL FOR EN BRÆNDSTOFCELLE BASERET PÅ ET TILSVARENDE KREDSLØBSDIAGRAM

Method for diagnosing and/or forecasting the service life of a fuel cell, comprising: applying an excitation signal to the cell at the first time, recording the impedance at frequencies of the excitation signal at the first time, determining a function for recorded impedances which contains functional components of a predetermined equivalent circuit diagram of the cell, wherein each functional component contains at least one equivalent circuit diagram component, the values of which can be parameterized, determining a parameter of an equivalent circuit diagram component of a functional component on the basis of the determined function suitable for the impedances recorded at the first time; applying an excitation signal to the cell at the second time; recording the impedance at frequencies of the excitation signal at the second time; determining the parameter of the equivalent circuit diagram component of the functional component on the basis of the determined function suitable for the impedances recorded at the second time; determining a temporal dependence for the parameter on the basis of the parameters determined for the first and second times; determining at least one sign of degradation of a part of the cell, which is assigned to the functional component of the equivalent circuit diagram, on the basis of the temporal dependence of the parameter for the functional component.