Accelerating Interfacial Desolvation Kinetic by NaF-Rich Composite Sodium for High-Performance All-Climate Sodium-Metal Batteries

Abstract

Sodium-metal batteries (SMBs) are considered as the ideal candidates for the next-generation large-scale energy storage batteries. However, achieving all-climate SMBs operating at a wide temperature remains a huge challenge because of the instability of the Na/electrolyte interphases and sluggish reaction kinetics, particularly at ultra-low temperature (−40 °C). Herein, we develop a novel NaF-rich composite sodium anode by impregnating NaF into metallic Na (NaF@Na) for the first time. By this design, NaF-rich SEI can be embedded into the anode homogeneously, which can endow the Na/electrolyte interface a good thermal stability at 60 °C and accelerate the desolvation of Na+-solvent molecular clusters at −40 °C. In light of these collective advancements, the NaF@Na||NVP full cell realized stable all-climate operation from −40 to 60 °C with commercial ester-based electrolyte, displaying a high-capacity retention of 90% after 400 cycles (0.2 C) even at −40 °C together with an outstanding electrochemical performance at 60 °C (106.1 mAh g−1, and 76% capacity retention over 2400 cycles at 10 C), which has rarely been achieved in previous reports. This unique composite Na anode designed offers new insights and prospects for all-climate operating, and lays the basis for practical SMBs later.