Impedance of a thin-film lithium-ion battery Si@O@Al|LiPON|LiCoO-=SUB=-2-=/SUB=- at temperatures from -20-=SUP=-o-=/SUP=-C to +50-=SUP=-o-=/SUP=-C

Abstract

The results on measuring the impedance of a solid-state thin-film lithium-ion battery of the Si@O@Al-LiPON-LiCoO2 electrochemical system in the temperature range from -20oC to +50oC are presented. A structural model is proposed and the parameters of its elements, providing the best fit for the experimental Nyquist diagrams, are calculated. It is shown that the main contribution to the internal resistance is made by the LiPON-LiCoO2 interface. Based on the temperature dependence of the LiPON solid electrolyte conductivity the activation energy of lithium is determined, which is in good agreement with the literature data. Keywords: Nanocomposite, lithium-ion battery, impedance spectroscopy, structural model, ionic conductivity.