Transient Removal in Electrochemical Impedance Spectroscopy for Battery Testing

This paper proposes a technique for the joint estimation of the transient and periodic components in the voltage signal associated with the injection of a multisine current into a rechargeable battery. Removal of the transient component is needed to avoid the effect of voltage variations occurring during the battery relaxation time when measuring the battery internal impedance, through electrochemical impedance spectroscopy. Both simulation and experimental results are provided to validate the proposed approach. It is shown that the technique is effective in removing the transient component in the battery voltage signal to allow estimation of the periodic component needed to measure the battery internal impedance, without having to wait for the expiration of the relaxation time.