Transferring the internal processes of the lead–acid battery to the lithium–sulfur battery by verification with electrochemical impedance spectroscopy

Daniel Martin Brieske, Alexander Warnecke, Dirk Uwe Sauer, Journal of Energy Storage, Vol. 43, November 2021.

Abstract

As one of the next generations of lithium–ion technology, the lithium–sulfur battery is considered a promising rechargeable energy system. Compared to the current lithium–ion technology, the lithium–sulfur battery has advantages such as high energy density as well as reducing the usage of rare earths such as nickel, manganese or cobalt because abundant sulfur is being used as a low cost alternative. Therefore, the attention to this energy storage has increased, both from a scientific and industrial point of view. In order to better understand the internal electrochemical processes of this technology, impedance-based models have been developed in various publications. However, these models differ in how they interpret the individual concentrated elements of the electrical equivalent circuit diagrams. In this paper, the internal process steps of a similar conversion reaction known from the lead–acid battery are compared and investigated with the process steps of a lithium–sulfur cell. The resulting equivalent circuit diagram is verified by electrochemical impedance spectroscopy of a prototype pouch cell. This demonstrates the transferability of selected process steps of the lead–acid battery to the lithium–sulfur technology.