The transition to a sustainable society is vital and requires electrification. Sodium and potassium ion-based electrolytes will likely play an important role in energy storage as these elements are very abundant. The latter cations and chloride are especially interesting since life on the planet is somehow based on biological transfers of these ions through cell membranes. K⁺ is the key charge carrier in plants. Here, we characterize electrochemically, electrostatically, and structurally novel electrolytes, K₃ClO and K_2.99Ba_0.005ClO, and compare their performance with Na₃ClO and Na_2.99Ba_0.005ClO in symmetric and asymmetric structural electrode-less cells, such as K/K_2.99Ba_0.005ClO in a cellulose membrane/K, Na/Na_2.99Ba_0.005ClO in a cellulose membrane/Na, Al/K_2.99Ba_0.005ClO composite/Cu, and Al/Na_2.99Ba_0.005ClO composite/Cu, at temperatures that range from −45 to 65 °C. An ab initio molecular dynamics structural study followed by band structure determination using density functional theory and hybrid simulations allowed us to compare the amorphous character of the structures, bandgap, and electron localization function for both K₃ClO at 25 °C and Na₃ClO at 37 °C, temperatures at which preliminary studies indicate that these compounds are already amorphous. As in Na⁺-based electrolytes, the ferroelectric character of the K⁺-based electrolytes is well recognizable, especially at −45 °C, where the relative real permittivity achieves 10¹³ in K/K_2.99Ba_0.005ClO in cellulose membrane/K symmetric cells for an ionic conductivity of ∼120 mS/cm. As in Na⁺-based electrodes-less structural battery cells, self-charge and self-cycling phenomena are also demonstrated reinforcing the ferroelectric nature of the A₃ClO (A = Li, Na, and K) family of electrolytes. These studies may contribute to understanding the K⁺ and Na⁺ transfer behavior in energy harvesting and storage as well as the biologic world.

The wetting behavior of liquid magnesium drop on pure tungsten substrates was investigated, for the first time, with the sessile drop method combined with non-contact heating and capillary purification of a Mg drop from a native oxide film. A specially designed apparatus dedicated to the investigation of the high-temperature interaction of dissimilar materials was used. The comparative experiments were performed under isothermal conditions at temperatures of 700 °C and 740 °C using two atmospheres: Ar + 5 wt.% H₂ and pure Ar, respectively. During high-temperature tests for 180 s, the images of the Mg/W couples were recorded with CCD cameras (57 fps) from two directions of observation. The solidified drop/substrate couples were subjected to structural characterization using scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). Under the applied measurement conditions, liquid Mg revealed non-wetting behavior on W substrates (a contact angle θ > 90°). The average value of the contact angle under the flowing Ar atmosphere at 740 °C was θ_av = 115°, whereas it was higher under the flowing Ar + 5 wt.%. H₂ atmosphere at a lower temperature of 700 °C, showing θ_av = 122°. Independently on employed atmosphere and temperature, SEM + EDS analysis of solidified sessile drop couples did not display any new phases and mass transfer between the Mg drop and the W substrate, whereas the presence of discontinuities at the Mg/W interface of cross-sectioned couples were well-distinguished. Non-wetting and a lack of permanent bonding between the Mg drop and W substrates have a good agreement with the Mg–W phase diagram calculated with the help of FactSage software and FTlite database, i.e., the non-reactive nature of the Mg/W couple because W does not dissolve in liquid Mg and it does not form any compounds with Mg. These findings allow for the recommendation of tungsten as a suitable refractory material for long-time contact with liquid Mg in different container-assisted methods of materials characterization as well as in liquid-assisted processing of Mg components.