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

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 — Na-based 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.