Identification of solid oxygen‐containing Na‐electrolytes: An assessment based on crystallographic and economic parameters

Abstract

We have scanned the inorganic crystal structure database using Voronoi-Dirichlet methodology for inorganic, crystalline, solid Na electrolytes and applied a total of nine different crystallographic and economic parameters in order to evaluate the potential of each material. Especially for stationary electrochemical energy storage -used to counteract the capricious nature of renewable energy sources and momentary variations of energy consumption -Nabased chemistries have a considerable market share. They rely on solid Na electrolytes separating the Na and S electrode compartments. We used data generated from the currently widest-spread Na electrolytes to lay a foundation for the crystallographic data mining and Voronoi-Dirichlet partitioning of the database. The structural data is the basis for the calculation of the above-mentioned parameters. We introduced an evaluation and scoring scheme to systematise the results and -depending on the weighting scheme -point towards the most promising materials. Aluminosilicates and transition metal oxides seem especially interesting but, depending on the weighting, any of the more than 400 candidates could be the next-generation solid Na electrolyte.

Empirical Electronic Polarizabilities: Deviations from the Additivity Rule. II. Structures Exhibiting Ion Conductivity

“…resulted in continuous migration paths noted in Table in column 2 for the confirmed Li‐ion conductors LiFePO 4 and Li 3 VO 4 and for the potential Li‐ion conductors LiGeBO 4 , CsLiB 6 O 10 , Li 2 Ti 3 O 7 , LiMn 0.88 Fe 0.17 PO 4 (lithiophilite), Li 2 NaPO 4 , and LiNaSO 4 . Similarly, using the procedure of Meutzner et al . resulted in continuous migration paths for the confirmed Na‐ion conductors Na 4 P 2 O 7 , and Na 2 SO 4 (thenardite), Na 6 Mg(SO 4 ) 4 (vanthoffite), and for the potential Na‐ion conductors Na 6 Mg 2 (CO 3 ) 4 SO 4 (tychite), Na 2 TiSiO 5 (natisite), NaPO 3 (Kurrol A), Na 3 SO 4 F (kogarkoite), Na 6 (SO 4 ) 2 FCl (sulfohalite), Na 15 (SO 4 ) 5 F 4 Cl (galeite), Na 21 (SO 4 ) 7 F 6 Cl (schairerite), Na 22 K(CO 3 ) 2 (SO 4 ) 9 Cl (hanksite), and Na 2 SeO 4 .…”

“…A later publication describes the search for compounds with infinite migration paths in 822 ternary Li a X b O z compounds and 1349 quaternary Li a X1 b X2 c O z compounds where they find a total of 251 identified as solid electrolytes out of 2171 Li compounds, and note conductive paths in LiAlSiO 4 (β‐eucryptite) and 3D conductivity in Li 4 P 2 O 7 . In addition, Meutzner et al . identified 52 and 402, respectively, high‐potential candidates for Na ion conductors.…”

“…In the previous section, we noted published 1D, 2D, and 3D migration paths in many Li and Na ion conductors . Now we use the VDP approach to examine the dimensionality of the remaining compounds exhibiting negative polarizability deviations.…”

Separators and electrolytes for rechargeable batteries: Fundamentals and perspectives

“…For solid electrolytes for Li and other monovalent and divalent ions, numerous works and reviews have been published discussing favourable crystal structure motifs for ion migration and how doping is used to improve the ion diffusivity in inorganic solids (e.g. [75,76,[81][82][83][84][85][86][87][88]). From all these studies as well as heuristic considerations, several factors can be extracted that provide high ion mobility in solids:…”

Sulfur‐ and Selenium‐Containing Compounds Potentially Exhibiting Al Ion Conductivity

“…Eventually, all VDP for all atoms, excluding Al, were constructed. As the minimum distance under which VDP are joined together, a value of 1 Å was chosen . All of these steps were carried out by using ToposPro.…”