High ionic conductivity and dendrite-resistant NASICON solid electrolyte for all-solid-state sodium batteries. (June 2021)

• Record Type: Journal Article
• Authors: Shen, L.; Yang, J.; Liu, G.; Avdeev, M.; Yao, X.
• Is Part Of: Materials today energy. Volume 20(2021)
• Publication Date: 2021-06
• Subjects: NASICON -- Structure -- Ionic conductivity -- Dendrite -- All-solid-state sodium batteries; Energy development -- Periodicals; Energy industries -- Periodicals; Power resources -- Periodicals; Energy policy -- Periodicals; Energy development; Energy industries; Energy policy; Power resources; Electronic journals; Periodicals; 621.042
• DOI: 10.1016/j.mtener.2021.100691
• Languages: English
• ISSNs: 2468-6069

Abstract

Abstract: The low ionic conductivity and poor dendrites suppression capability of Na3 Zr2 Si2 PO12 solid electrolyte limit the practical application of all-solid-state sodium batteries. Herein, the optimized Na3.4 Mg0.1 Zr1.9 Si2.2 P0.8 O12 electrolyte is obtained by simultaneously substituting the Zr 4+ with Mg 2+ and P 5+ with Si 4+ through solid-state reaction. The Na3.4 Mg0.1 Zr1.9 Si2.2 P0.8 O12 electrolyte has superior room temperature ionic conductivity of 3.6 × 10 −3 S cm −1, which is 17 times higher than that of pristine Na3 Zr2 Si2 PO12 . No short circuit of the Na/Na3.4 Mg0.1 Zr1.9 Si2.2 P0.8 O12 /Na symmetric battery is observed up to 2.0 mA cm −2, and the symmetric battery displays stable sodium plating/stripping cycles for over 2000 h at 0.1 mA cm −2 and 300 h at 1.0 mA cm −2 . The resultant Na3.4 Mg0.1 Zr1.9 Si2.2 P0.8 O12 electrolyte is further employed in two all-solid-state sodium batteries. The Na3 V2 (PO4 )3 /Na3.4 Mg0.1 Zr1.9 Si2.2 P0.8 O12 /Na all-solid-state sodium battery maintains a discharge capacity of 93.3 mAh g −1 at 0.1C after 50 cycles, and the FeS2 /Na3.4 Mg0.1 Zr1.9 Si2.2 P0.8 O12 /Na all-solid-state sodium battery delivers a discharge capacity of 173.1 mAh g −1 at 0.1C after 20 cycles, which are significantly enhanced compared with those based on pristine Na3 Zr2 Si2 PO12 . This strategy provides an efficient method to prepare optimized NASICON solid electrolytes with high ionic conductivity and excellent dendrites suppression capability and promotes the practical application of all-solid-state sodium batteries. Graphical abstract: Image 1 Highlights: The Na3.4 Mg0.1 Zr1.9 Si2.2 P0.8 O12 electrolyte is synthesized by dual substitution of Zr 4+ and P 5+ by Mg 2+ and Si 4+ . The highest ionic conductivity of 3.6 × 10 −3 S cm −1 is realized for Na3.4 Mg0.1 Zr1.9 Si2.2 P0.8 O12 . The optimized electrolyte delivers outstanding dendrite resistance capability. All-solid-state sodium batteries show superior electrochemical performances.