Na₃SbS₄: A Solution Processable Sodium Superionic Conductor for All‐Solid‐State Sodium‐Ion Batteries

Abstract

All-solid-state sodium-ion batteries that operate at room temperature are attractive candidates for use in largescale energy storage systems.However,materials innovation in solid electrolytes is imperative to fulfill multiple requirements, including high conductivity,functional synthesis protocols for achieving intimate ionic contact with active materials,a nd air stability.Anew,h ighly conductive (1.1 mS cm À1 at 25 8 8C, E a = 0.20 eV) and dry air stable sodium superionic conductor, tetragonal Na 3 SbS 4 ,isdescribed. Importantly,Na 3 SbS 4 can be prepared by scalable solution processes using methanol or water,a nd it exhibits high conductivities of 0.1-0.3 mS cm À1 . The solution-processed, highly conductive solidified Na 3 SbS 4 electrolyte coated on an active material (NaCrO 2 ) demonstrates dramatically improved electrochemical performance in all-solid-state batteries.

Room-Temperature All-solid-state Rechargeable Sodium-ion Batteries with a Cl-doped Na3PS4 Superionic Conductor

“…This overall conductivity is higher than that of Si-doped c-Na 3 PS 4 (0.74 mS cm −1 )29 and is the highest value for sodium thiophosphates achieved thus far. Although the recently reported Na 3 PSe 4 and Na 3 SbS 4 have higher conductivities, the more expensive and less stable Se 2− anion is utilized in Na 3 PSe 4 14, while Na 3 SbS 4 requires a more complicated electrolyte bilayer approach using c-Na 3 PS 4 to stabilize the interface at the Na anode20.…”

“…Chalcogenide-based (S, Se) chemistries offer the potential for higher ionic conductivities than oxides11121314151617181920. Though it is likely that sulfide and selenide-based solid electrolytes may exhibit lower intrinsic electrochemical stability, the formation of passivating phases at the electrode-solid electrolyte interface can potentially mitigate further reactions212223.…”

Reactivity-Guided Interface Design in Na Metal Solid-State Batteries

“…Using the first-principles methodology developed previously, 22,25 the decomposition products of a conductor can be predicted under different Li or Na chemical potentials. Taking Na 3 SbS 4 , a recently reported superionic Na conductor, 19,33 and Na metal as an example, the most thermodynamically favorable reactions (if any) occurring between the Na-ion conductor and Na metal reservoir is calculated to be 8 Na + Na 3 SbS 4 / 4 Na 2 S + Na 3 Sb:…”

“…To date, various highly conductive inorganic solid conductors have been discovered, such as perovskite-type, 3 sodium superionic conductor (NASICON)-like, [4][5][6] garnettype, [7][8][9] and sulfide-type materials. [10][11][12][13][14][15][16][17][18][19] In addition, general design principles have been developed to achieve high ionic mobility. 20 It is now generally accepted that solid-state batteries will have to use metallic Li/Na anodes to be able to surpass traditional Li-ion cells in energy density.…”

Ionic Conductivity of the NASICON‐Related Thiophosphate Na1+xTi2−xGax(PS4)3

“…[36][37][38] In addition to the Li 10 GeP 2 S 12 derived structures, recent work has also focusedo nN a-Sb-Sc ompounds for ionic conductors. [39] Herein, in an effort to further widen the materials space of sodium ion conductors,t he Na + ionic conductivity of the thio-NASICON analogue NaTi 2 (PS 4 ) 3 (NTPS) and the effects of Gasubstitution in Na 1 + x Ti 2Àx Ga x (PS 4 ) 3 are explored. The aliovalent substituent of gallium was chosen for the substitution of titanium to enable the successful incorporation, due to the comparable ionic radii( r(Ga 3 + ) = 0.62 and r(Ti 4 + ) = 0.605 for octahedral coordination), [40 ] whilea lso increasing the carrier concentration towardenhancing the ionic conductivity.Impedance spectroscopy shows an ionic conductivity of approximately 10 À6 Scm À1 that can further be increased using aliovalent substitutionw ith Ga.…”