Dendrite‐Free Sodium Metal Anodes Enabled by a Sodium Benzenedithiolate‐Rich Protection Layer
Ming Zhu, Guanyao Wang, Xing Liu, Bingkun Guo, Gang Xu, Zhongyi Huang, Minghong Wu, Huan Liu, Shi Xue Dou, Chao Wu
Abstract
Abstract Sodium metal is an ideal anode material for metal rechargeable batteries, owing to its high theoretical capacity (1166 mAh g −1 ), low cost, and earth‐abundance. However, the dendritic growth upon Na plating, stemming from unstable solid electrolyte interphase (SEI) film, is a major and most notable problem. Here, a sodium benzenedithiolate (PhS 2 Na 2 )‐rich protection layer is synthesized in situ on sodium by a facile method that effectively prevents dendrite growth in the carbonate electrolyte, leading to stabilized sodium metal electrodeposition for 400 cycles (800 h) of repeated plating/stripping at a current density of 1 mA cm −2 . The organic salt, PhS 2 Na 2 , is found to be a critical component in the protection layer. This finding opens up a new and promising avenue, based on organic sodium slats, to stabilize sodium metals with a protection layer.