A Differential Impedance Method for Investigation of Porous Lithium- and Metal Hydride- Battery Electrodes

摘要

A method, denoted differential impedance, is presented. The aim is to improve the use of electrochemical impedance spectroscopy (eis) in the study of porous electrodes. This is accomplished by using two references, one at each side of the porous electrode. The eis-measurement is run as usual and the additional reference at the back acquires a second impedance. This is advantageous, for example, when porous behaviour is strong or if there are solid phase conductivity limitations. The method is illustrated using a physio-chemical model for a battery electrode and is thereafter tested on metal hydride-and LiMn{sub}2O{sub}4-electrodes.