Xia Xianming, Chen Kaizhi, Xu Shitan, Yao Yu, Liu Lin, Xu Chen, Rui Xianhong, Yu Yan
Guangdong Provincial Key Laboratory on Functional Soft Condensed Matter School of Materials and Energy Guangdong University of Technology Guangzhou 510006 China.
Hefei National Research Center for Physical Sciences at the Microscale Department of Materials Science and Engineering CAS Key Laboratory of Materials for Energy Conversion University of Science and Technology of China Hefei Anhui 230026 China.
Small Sci. 2023 Jun 7;3(7):2300038. doi: 10.1002/smsc.202300038. eCollection 2023 Jul.
Sodium metal, benefiting from its high theoretical capacity and natural abundance, is regarded as a promising anode for sodium-metal batteries (SMBs). Unfortunately, the uncontrollable sodium dendrites formation caused from the sluggish ion-transport kinetics and fragile solid electrolyte interphase (SEI) interlayer induces a low Coulombic efficiency and poor cycling stability. Constructing an artificial SEI interlayer with high ionic conductivity, stability, and mechanical toughness is an effective strategy for Na-metal anode, yet it still presents major challenge for high current density and long cycling life. Herein, an artificial SEI interlayer composed of Na-Sn alloy, Sn, and NaTe (denoted as NST) is designed via in-situ conversion/alloying reaction of tin telluride (SnTe) with Na. Such artificial interlayer possesses rapid Na-transport kinetics and high Young's modulus (5.3 GPa), benefitting to even Na plating/stripping and suppressing Na dendrite growth. Owing to these merits, the symmetrical Na/NST cell presents an ultralong cycle life span over 1390 h with a small voltage hysteresis at 1 mA cm with 1 mAh cm. And the NaV(PO) (NVP)||Na/NST full cell exhibits a prolonged life of 1000 cycles with a high-capacity retention of 88% at 5C. Herein, a promising strategy is provided to construct a high-performance artificial interlayer for SMBs.
金属钠因其高理论容量和天然丰度，被视为钠金属电池（SMBs）的一种有前景的负极材料。不幸的是，离子传输动力学迟缓以及固态电解质界面（SEI）层脆弱导致钠枝晶形成不可控，从而引发低库仑效率和较差的循环稳定性。构建具有高离子导电性、稳定性和机械韧性的人工SEI层是钠金属负极的有效策略，但对于高电流密度和长循环寿命而言，这仍然面临重大挑战。在此，通过碲化锡（SnTe）与钠的原位转化/合金化反应，设计了一种由Na-Sn合金、Sn和NaTe组成的人工SEI层（表示为NST）。这种人工层具有快速的钠传输动力学和高杨氏模量（5.3 GPa），有利于实现均匀的钠电镀/剥离并抑制钠枝晶生长。由于这些优点，对称的Na/NST电池在1 mA cm²、1 mAh cm²条件下呈现出超过1390小时的超长循环寿命以及小电压滞后。并且NaV(PO₄)₃（NVP）||Na/NST全电池在5C下表现出1000次循环的延长寿命和88%的高容量保持率。在此，提供了一种有前景的策略来构建用于钠金属电池的高性能人工层。
