Lopes, Vitor V.Rangel, C. M.Novais, Augusto Q.2013-09-232013-09-232013Lopes, V. Vitor; Rangel, C.M.; Novais, Augusto Q. Electrochemical impedance spectroscopy modeling using the dis-tribution of relaxation times and error analysis for fuel cells. In: HYCELTEC'2013 - IV Iberian Symposium on Hydrogen, Fuel Cells and Advanced Batteries, Book of Abstracts, Estoril, 26-28 June, 2013http://hdl.handle.net/10400.9/1995This paper proposes a new approach to determine the distribution of relaxation times (DRT) directly from the electro-chemical impedance spectroscopy (EIS) data, i.e. without the use of an equivalent electrical circuit model. The method uses a generalized fractional-order Laguerre basis to represent EIS where both the parameters of the basis and their co-efficients are estimated by solving a nonconvex minimization problem. Furthermore, the DRT confidence region is de-termined to assess the accuracy and precision of the DRT estimate. The approach is applied to analyze the dominant dynamic properties of an open-cathode hydrogen fuel-cell under different current and air-flow conditions. Results showed that the estimated DRT closely reconstructs EIS data even when there is a higher variance at smaller relaxation times.engFuel cellsImpedance spectroscopyDistribution relaxation timesParameter estimationResiduals bootstrapconference object