Designing gradient solid electrolyte interphase for stable lithium metal batteries

The practical application of lithium metal batteries (LMBs) has been impeded by the unstable electrolyte interphase and uncontrollable Li dendrites growth. The structures and components of solid electrolyte interphase (SEI) are extremely important to affect the electrochemical performance of LMBs, but it is hard to regulate them due to the complicated reaction mechanisms. Therein, a gradient SEI layer was designed by adding bisfluoroacetamide into electrolyte, which could guide the uniform deposition of Li ions and suppress the growth of Li dendrites. In addition, this additive also could improve the stability of cathode, resulting in a stable LMBs.