Accounting for stray capacitances in impedance measuring cells — A mandatory step in the investigation of solid ion conductors

• Published in: Solid state ionics Vol. 393; p. 116169
• Main Authors: Komar, Alexander, Wilmer, Dirk, Wilkening, H. Martin R., Hanzu, Ilie
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2023
• Subjects: Dielectric materials; Electrical relaxation; Impedance conductivity; Measuring methods; Solid electrolytes; Stray capacitance; Measuring methods; Electrical relaxation; Solid electrolytes; Dielectric materials; Stray capacitance; Impedance conductivity
• ISSN: 0167-2738; 1872-7689
• DOI: 10.1016/j.ssi.2023.116169

The determination of the dielectric response properties is essential to the investigation of solid ion conductors. The stray capacitance contributions of the measuring cell must be systematically determined and subtracted from the acquired data. Hereby, we report and discuss a general method that can be used for the accurate determination of stray capacitance in impedance measuring cells. Our method can be applied to all commercial or custom-made impedance cells or sample holders used for variable temperature conductivity measurements of fast ion conductors. After the description of the method, we present the experimental calibration done for a 2032-type coin cell sample holder. The 2032-type coin cell is a highly reliable sample holder for impedance measurements of air sensitive materials. We tested the method on a known sample and we validated it by comparing with the results obtained in a simple reference configuration. Our simple, efficient and robust method for the determination of parasitic capacitive contributions may serve as an example of good practice in the field of solid electrolytes, solid state batteries and dielectric materials investigations. •A general method for the determination of stray capacitances in impedance cells.•Coin cells as reliable sample holders for impedance on air sensitive samples.•Better than 0.1 pF accuracy of capacitance measurements in coin cells.