Optimizing the Na metal/solid electrolyte interface through a grain boundary design

Abstract

Poor compatibility between alkaline metal electrode and solid electrolyte at interfaces is the critical issue of solid-state metal batteries. We propose a grain boundary sealing (GBS) design of Na3Zr2Si2PO12 (denoted...

Uniform Na Metal Plating/Stripping Design for Highly Reversible Solid‐State Na Metal Batteries at Room Temperature

“…The intercept is considered as the resistance of the solid electrolyte ( R SE ) and the semicircle is related with the charge transfer resistance ( R inter ) at the Na metal/solid electrolyte interface. [ 18,47 ] The R SE and R inter of the fresh Na|CuO@NZSPO|Na cell are determined to be 117.5 and 461.3 Ω cm 2 , respectively. Then, the R inter sharply decreases from the second day and reaches a stable value of 191.5 Ω cm 2 , which is retained even until the 15th day.…”

“…Furthermore, as shown in Figure 4h, the excellent performance of the CuO@NZSPO solid electrolyte surpasses those of the previously reported NZSPO‐based solid electrolytes, [ 20,21,30,31,48–51 ] such as the Na‐deficient NZSPO, [ 50 ] TiO 2 coated NZSPO, [ 22 ] SnO 2 modified NZSPO, [ 30,31 ] and GBS‐NZSPO. [ 47 ]…”

“…Furthermore, as shown in Figure 4h, the excellent performance of the CuO@NZSPO solid electrolyte surpasses those of the previously reported NZSPO-based solid electrolytes, [20,21,30,31,[48][49][50][51] such as the Na-deficient NZSPO, [50] TiO 2 coated NZSPO, [22] SnO 2 modified NZSPO, [30,31] and GBS-NZSPO. [47] A solid-state Na metal full battery was assembled to examine the practical application of CuO@NZSPO as an advanced solid electrolyte. The battery configuration is illustrated in Figure 5a, where Na metal foil acts as the anode and CuO@NZSPO as the solid electrolyte to couple with a succinonitrile-NaClO 4 plastic crystal electrolyte (PCE) composite cathode.…”

NaSICON: A promising solid electrolyte for solid‐state sodium batteries

“…[ 98 ] The optimum ionic conductivity was observed with 5 wt% ATO additive, owing to increased grain boundary conductivity, which is attributed to the highly dense structure, and improved purity. Other additives such as the addition of Bi 2 O 3 , [ 99 ] Na 3 BO 3 , [ 100 ] Na 2 SiO 3 , [ 101 ] Na 2 B 4 O 7 , [ 102 ] and (ZnO) 2 –(B 2 O 3 ) 3 [ 103 ] have also been reported facilitated Na + ‐ion transport owing to the same reasons, indicating the broad effectiveness of this strategy. The as‐formed second phase in the studied range of these dopants and the corresponding conductivities of these systems are summarized in Figure 1F,G, respectively.…”

Solid electrolytes for solid-state Li/Na–metal batteries: inorganic, composite and polymeric materials

“…Also, sintering aids, i.e. La 2 O 3 , 71 Na 2 B 4 O 7 , 72 and ZnO–B 2 O 3 , 73 were used to densify the grain boundaries and promote the ion conduction along the grain boundaries, thus reducing the Na–NASICON interface impedance. Accordingly, exploring NASICON-type electrolytes with nanoscale grains is an opening for applying nano-ceramics in solid-state batteries.…”