A solution for three-electrode measurements on pre-sintered samples
Some solid-state battery components, like those based on Li7La3Zr2O12 (LLZO) electrolytes, must be sintered at elevated temperatures, making the use of three-electrode setups difficult. In these cases, we employ a wire-ring reference electrode that can be pressed against the sides of the pre-sintered electrolyte pellet, enabling a three-electrode configuration.
In a new application note, we used a platinum wire-ring that was plated with lithium in situ to form a stable, well-known reference potential. The experiments were performed with the CompreCell12DP-3e (equipped with a PEEK Sleeve Set for Wire Ring Reference) in the CompreDrive.
In collaboration with FZ Jülich
In this application note, charge/discharge cycling and electrochemical impedance spectroscopy (EIS) in three-electrode mode were performed on a fully inorganic all-solid-state cell consisting of a lithium metal anode, an LLZO separator, and a LiNi0.8Mn0.1Co0.1O2 (NMC811) based composite cathode. The sample was prepared at Forschungszentrum Jülich as described in an earlier publication.
The three-electrode measurements revealed that the lithium metal anode is not limiting for the cell performance, having a charge-transfer resistance two orders of magnitude smaller than the cathode, as clearly visible above: The NMC and full cell spectra are almost overlapping, while the Li impedance (shown enlarged in the inset) is much smaller.
To cite this application note, please use: “Folkers-Karlsson et al., rhd instruments GmbH & Co. KG, Application Note: A Wire Ring Reference Electrode for Sintered Oxide Ceramic Solid-State Battery Samples, November 2025, https://docs.rhd-instruments.de/appnotes/application-note_CC12DP3e-Wire-Ring.pdf”.