Electrolytic material with NASICON structure for solid sodium ion batteries and process for their preparation

摘要

The invention relates to a method for the production of electrolyte material with a NASCION structure based on a Na 2 + xSc x Zr 2 -x (SiO 4) 2 (PO 4) compound with 0 ≦ x 2, wherein initially an acidic, aqueous solution is provided the sodium, scandium and zirconium in the form of water-soluble nitrates, acetates or carbonates, and soluble silicates or orthosilicic acids or organic silicon compounds are dissolved in dissolved form according to the desired stoichiometry. Subsequently, phosphoric acid or ammonium dihydrogen phosphate or other soluble phosphates are added according to the desired stoichiometry, with complex zirconium dioxide phosphates forming as colloidal precipitates. The mixture with the precipitates is then dried and calcined. The sodium ion-conducting powder thus produced with a NASCION structure comprising a Na 2 + x Sc x Zr 2 -x (SiO 4) 2 (PO 4) compound with 0 ≦ x ≦ 0.6 has a particle size of less than 0.1 μm and advantageously an ionic one Conductivity of more than 1 · 10-3 S / cm at 25 ° C. For sodium ion-conducting powder with 0.3 ≤ x ≤ 0.6 even ionic conductivities of more than 3 · 10-3 S / cm at 25 ° C could be determined. The powder thus produced can be advantageously subsequently ground and pressed. As a dense membrane, this material is particularly advantageous for use with solid sodium ion batteries.