Ion conductivity of ceramic electrolytes sets a limit to their use in batteries; correct analysis of this parameter opens a gate for further material optimization. Electrochemical impedance spectroscopy (EIS) is the only way to characterize ionic conductivity, but the data obtained could vary from researcher to researcher for a number of reasons. Our goal was to propose a unified approach on the basis of both the published data and our own experience. We synthesized pure Li1.3Al0.3Ti1.7(PO4)3 and analyzed it using EIS, powder X-ray diffraction analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. We show how to (1) obtain reliable EIS spectra; (2) verify the equivalent circuit by adjusting the temperature; and (3) estimate the error of measurement via three approaches highlighting their use for special research aims. Finally, we summarized parameters that should be checked when describing results and benchmarking the results with literature. The article will be useful for those who work with ion-conducting ceramics.

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The interest in alternative energy sources grows rapidly and demands improved materials. The cutting-edge investigations focus attention on the development and optimization of solid electrolytes for advanced energy storage. Their chemical and structural stability defines both battery performance and lifetime, yet it is studied poorly even for well-known superionic conductors such as NASICON-based compounds. In this work, we studied the Li1.3Al0.3Ti1.7(PO4)3 (LATP) stability toward water. Corresponding ceramics were synthesized in pellet form through the solid-state reaction and had been immersed in deionized water for different periods of time with subsequent electrochemical (electrochemical impedance spectroscopy), structural (powder X-ray diffraction analysis, Raman spectroscopy, computational modeling), chemical (ceramicsenergy-dispersive X-ray spectroscopy; mother-solutionsinductively coupled plasma mass spectrometry), and morphological (scanning and transmission electron microscopy) analyses. Water exposure triggers drastic conductivity losses (64% for σt) with accompanying lithium elution (exceeds 13 atomic%) and unit cell shrinkage. All these changes reach a plateau after 2 h of water exposure.

Manual cell assembly confounds with research digitalization and reproducibility. Both are however needed for data-driven optimization of cell chemistries and charging protocols. Therefore, we present herein an automatic battery assembly...