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Lithium phosphorus sulfuric oxide nitride (LiPSON) is prepared by radio frequency (RF) sputtering using a sputter target with compositions of 50 wt% Li3PO4 and 50 wt% Li2SO4. Knowledge about the present phases at the solid electrolyte–lithium anode interface, the so‐called solid electrolyte interphase (SEI), is achieved by performing an in situ sputtering of metallic lithium on the electrolyte and subsequently measuring the chemical bonding by X‐ray photoelectron spectroscopy (XPS). Information about the SEI is of essential interest to understand the process of lithium‐ion conduction in the half cell. Therefore, the information about the formation of lithium phases in the SEI is crucial. [ABSTRACT FROM AUTHOR]

Herein, the proof of concept of a sodium polysulfide battery consisting of two electrode chambers being separated by a solid electrolyte is described. The concept is suited for dissolved polysulfide cathodes and has the advantage that both half reactions can be optimized separately. The formation of solid sulfide discharge products is identified as the major limiting factor for cell cycling. This issue can be alleviated by adding solid P2S5. Further improvement can be achieved by replacing diglyme (2G) as the cathode compartment solvent with tetramethylurea (TMU). Using TMU, the cell cycles with Coulombic efficiencies >99% and capacities of 800 mAh g−1 are maintained for at least 30 cycles. Viscosity, density, conductivity, and the electrochemical stability window values of the 2G‐ and TMU‐based electrolytes are compared. The latter shows higher viscosity (2.806 vs 1.603 mPa s), higher density (1.016 vs 0.996 g cc−1), and higher conductivity (4.27 vs 1.45 mS cm−1). The oxidative stability limit of the TMU electrolyte is 3.2 V versus Na+/Na, which is sufficient for polysulfide redox reactions. Vis spectroscopy is used to follow the electrode reaction. In case of TMU, the reaction is based on the redox activity of S3−• radicals (blue coloration of the catholyte solution). [ABSTRACT FROM AUTHOR]

Lithium phosphorous sulfuric oxynitrides (LiPSON) with different compositions have been prepared by rf‐sputtering using sputter targets with various mixtures of Li3PO4 and Li2SO4. Morphology, composition, and electrochromic properties of the fabricated thin films were investigated using solid state analysis methods like scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), optical transmission spectroscopy, and electrochemical impedance spectroscopy. The composition of the thin films changes due to the varying fractions of process gases. The highest fraction of sulfur is about 1.3 at% validated using XPS. The optical bandgap shifts in the range of 3.7 eV up to 5.3 eV for the different fractions of process gases. Transmission in the UV range is above 60% for most of the sputtered solid electrolyte thin films whereas in the visible range of the electromagnetic spectrum a transmission above 80% is observed. The highest ionic conductivity is identified for the thin films with 4 sccm nitrogen and no additional argon as process gas. However, ionic conductivity is expected to increase with increasing sulfur content and with change of the ratio between different nitrogen coordinations. [ABSTRACT FROM AUTHOR]

In the light of a more detailed view into the conduction paths of the Li7P3S11 structure, a hot press setup is described which facilitates both the preparation of the solid electrolyte and impedance spectroscopic investigations under simultaneous temperature- and pressure-monitoring. [ABSTRACT FROM AUTHOR]

α-LiZr2(PO4)3 is prepared by a sol-gel approach from a stoichiometric solution of Li(OAc) and ZrO(NO3)2 in HNO3 to which EDTA and citric acid is given at pH <7. [ABSTRACT FROM AUTHOR]