Lithium ion batteries (LIBs) have been widely applied in consumer electronic devices and are currently expanding their applications in electric vehicles (EVs). However, the increasing concern about the limitation of Li resources has stimulated the development of alternative energy storage systems. In this regard, sodium (Na) ion batteries (SIBs) are now emerging as a promising alternative to LIBs, due to the natural abundance of Na resources. In recent years, a lot of researches have been focused on the identification of non-graphitic carbonaceous anode materials as anodes for SIBs, but the working voltage of those anodes is mostly well above that of the Na/Na⁺ couple, leading to a lower battery operating voltage and hence a much lower energy density in comparison with LIBs. The direct use of Na metal as a battery anode would therefore be highly advantageous as it exhibits the highest specific capacity (1165 mAh g^-1) and the lowest redox potential (-2.714 V vs. standard hydrogen electrode) in SIB system. However, a critical challenge that still hinders direct use of Na metal as anode for sodium metal batteries (SMBs) is the high reactivity of Na metal with electrolytes, which primarily leads to the low coulombic efficiency (CE) of Na depostion/stripping and the poor cycling of SMBs. Here, we report the high rate, high efficiency operation of SMBs using a novel electrolyte using sodium bis(fluorosulfonyl)imide (NaFSI) salt. The electrolyte with 1.5 M NaFSI has been demonstrated to ensure the dendrite-free Na deposition with high CE of > 99%, and fast-charging (20C) and long cycle life (95% retention after 10,000 cycles) of SMBs. More details about this investigation will be provided and discussed in this presentation.