An Electrochemical Impedance Spectroscopy Method Applied to Porous LiMn[sub 2]O[sub 4] and Metal Hydride Battery Electrodes

Abstract

An electrochemical impedance spectroscopy method utilizing the signals from reference electrodes positioned in front of and behind a porous electrode is investigated. The basis for the method is illustrated theoretically, and limiting values under different assumptions are presented. The method was applied to a porous metal hydride and a battery electrode. It was concluded that the method facilitates the separation of local impedance effects from the effects of the potential distribution in the porous electrode. Consequently, a more accurate determination of local kinetic parameters and the effective conductivity in the pore electrolyte could be obtained. © 2003 The Electrochemical Society. All rights reserved.