Room temperature demonstration of a sodium superionic conductor with grain conductivity in excess of 0.01 S cm⁻¹ and its primary applications in symmetric battery cells

Abstract

The lack of suitable candidate electrolyte materials for practical application limits the development of all-solid-state Na-ion batteries.

Polyanionic Lattice Modifications Leading to High‐Entropy Sodium Ion Conductors: Mathematical Solution of Accessible Compositions

“…x Zr 2 (SiO 4 ) x (PO 4 ) 3-x ends with Na 4 Zr 2 (SiO 4 ) 3 and compositions with 2 < x < 2.5 have shown the highest ionic conductivity of all NaSICON materials. [17,20] The variation of the phosphate groups can theoretically be extended by many polyanions starting from (LiO 4 ) 7À to (WO 4 ) 2À with central tetrahedral elements such as Li, Mg, Ti, V, W, Fe, Cr, Mn, Zn, B, Al, Ga, Si, Ge, Sn, P, As, Sb, S, Se, similar to the wide chemical variability of garnets [21] or glaserites. [22] For the sake of simplicity, we restrict the selection of polyanions to those which a) do not belong to transition elements excluding compositions that might act as electrode materials instead of solid electrolytes, b) are fairly cheap and abundant leading to the exclusion of polyanions such as (GaO 4 ) 5À and (GeO 4 ) 4À and c) have unrealistically large ionic radii or unusual valencies, which presumably do not fit into the NaSICON structure.…”

Preparation and electrical conductivity of (Cu0.5Ag0.5)7SiS5I-based superionic ceramics

“…Since the e ciency of batteries directly depends on the properties of the working material, so the search for and improvement of new materials is relevant. Sulfur-containing solid electrolytes attract considerable attention due to the high ionic conductivity, which is provided by the peculiarities of their crystal structure [5,6,[9][10][11][12], among which it is worth noting complex phosphorus sul des with Li + and Na + . Usually sulfur-containing superionic compounds with ionic conductivity of Li + and Na + are di cult to obtain in the crystalline state [11], so they are obtained in glass-ceramic form [10,11,13,14].…”

Stepwise Hollow Prussian Blue Nanoframes/Carbon Nanotubes Composite Film as Ultrahigh Rate Sodium Ion Cathode

“…In order to meet the greatly increased energy consumption demand, the development of sodium ion batteries (SIBs) technologies with low cost, long life, and high electrochemical performance are imminent. [ 1–5 ] In the last decade, researchers have explored many cathode materials used in SIBs, [ 6–8 ] including sodium superionic conductor materials, [ 9–11 ] sodium‐based layered oxides, [ 12–15 ] fluorophosphates, [ 16–18 ] and organic materials. [ 19 ] However, the restricted space of layered oxide for sodium ions diffusing due to the close‐packed oxygen ion array connected to transition metal elements severely hinders the improvement of SIBs performance.…”