Electrothermal Impedance Spectroscopy as a Cost Efficient Method for Determining Thermal Parameters of Lithium Ion Batteries: Prospects, Measurement Methods and State of Knowledge

Current lithium-ion battery research aims in not only increasing their energy density but also power density. Emerging applications of lithium-ion batteries (HEV, PHEV, grid support) are becoming more and more power demanding.
The increasing charging and discharging power capability rates of lithium-ion batteries raises safety concerns and requires thermal management of the entire battery system. Moreover, lithium-ion battery’s temperature influences both battery short term (capacity, efficiency, self-discharge) and long-term (lifetime) behaviour. Thus, thermal modelling of lithium-ion battery cells and battery packs is gaining importance.
Equivalent thermal circuits’ models have proven to be relatively accurate with low computational burden for the price of low spatial resolution; nevertheless, they usually require expensive equipment for parametrization.
Recent research initiated by Barsoukov et al. proposed electrothermal impedance spectroscopy (ETIS) as a novel and non-destructive method of characterizing the thermal properties of batteries by defining frequency dependent thermal impedance.
This paper aims to systematize the state of knowledge about ETIS, presents measurement methods on the example of a high-power LiMO2/Li4Ti5O12 battery cell and discusses the prospect.