L.F. Wang, N.Q. Ren, Y. Yao, H. Yang, W. Jiang, Z.X. He, Y. Jiang, S.H. Jiao, L. Song, X.J. Wu, Z.-S. Wu* and Y. Yu*
Angewandte Chemie International Edition, 2022, e202214372.
DOI: 10.1002/anie.202214372 [PDF]
Metallic Na is a promising metal anode for large-scale energy storage.Nevertheless, unstable solid electrolyte interphase (SEI) and uncontrollable Na dendrite growth lead to disastrous short circuit and poor cycle life.Throughphase field andab initiomolecular dynamics simulation, we first predict that thesodium bromide (NaBr) withthe lowestNa iondiffusion energy barrieramong sodium halogen compounds (NaX, X = F, Cl, Br, I)is the ideal SEI composition to induce the spherical Na deposition for suppressing dendrite growth.Then, 1,2-dibromobenzene (1,2-DBB) additive is introduced into the common fluoroethylene carbonate-basedcarbonateelectrolyte (the corresponding SEI has high mechanical stability)to construct a desirableNaBr-rich stable SEI layer. When the Na||Na3V2(PO4)3cell utilizes the electrolyte with 1,2-DBB additive, an extraordinary capacity retention of 94% is achieved after 2000 cycles at a high rate of 10 C. This study provides a design philosophy for dendrite-free Na metal anode and can be expanded to other metal anodes.
