An EIS based study of a Ni–MH battery prototype. Modeling and identification analysis

E. B. CASTRO; D. J. CUSCUETA; R. H. MILOCCO; A. A. GHILARDUCCI; H. SALVA

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2009

0360-3199

Modeling and simulation of the dynamics of batteries is a useful method to improve designand predict their performance. This paper outlines the development of a simple physicochemicalmodel to simulate the impedance response of the Ni–MH battery system. Themodel describes the individual electrodes as porous flooded structures where the electrochemicalprocesses take place at the active material/electrolyte interface. The physicochemicalsystem parameters are grouped in such a way that the derived simple modelcan be experimentally identifiable. Experimental electrochemical impedance spectroscopy(EIS) data, recorded with a laboratory built prototype, are used to identify the modelparameters by fitting the theoretical impedance function derived from the model. Ananalysis of the predicted dependence of the impedance function with the battery SOC andthe identifiability of different system parameters are presented.