Characterization of different electrolyte composition Lithium Thionyl Chloride reserve battery by Electrochemical Impedance Spectroscopy

Electrochemical Impedance Spectroscopy (EIS) characterization for electrochemical processes in Lithium Thionyl Chloride reserve primary battery is shown. Two different electrolyte compositions are used to distinguish the changes in the EIS response. Galvanostatic EIS at discharge technique is used to obtain Kramers-Kronig compatible data for the reserve primary battery. The EIS data is analyzed by means of Equivalent Circuit models. The analysis shows the presence of five time-constants belonging to the electrochemical processes at Lithium anode, Solid Electrolyte Interface and the porous Carbon cathode. The change in the electrolyte composition causes the variation in the Solid Electrolyte Interface configuration and the kinetics of the Li anode processes. No variation in the cathode electrochemical processes observed by changing the electrolyte. The obtained results show the power of the non-destructive and in situ EIS technique to reveal the parameters for the electrochemical processes inside energy storage systems.