Characterization of lithium-thionyl chloride cells by impedance techniques

The main contributor to voltage drop observed on initial discharge of lithi um-thionyl chloride cells is the resistance of the passive layer an the lit hium anode, as can be determined from the Nyquist plot of a lithium-thionyl chloride cell. At extremely low discharge currents, initial voltage drop c orresponds to the value found from the impedance measurements; at higher cu rrent, an empirical correction based on the experimental results is require d. The dispersion in the values of the impedance parameters and thus in ini tial voltage drop of individual cells was analyzed. The condition of the li thium surface after assembly was shown not to be the only reason for high d ispersion in impedance parameter values. (C) 2001 Elsevier Science B.V. All rights reserved.