The synergistic effect of lithium bis(fluorosulfonyl)imide and lithium nitrate for high-performance lithium metal anode

Commercialization of the LMBs is subject to two formidable technical challenges, the instability of Li metal against all the organic solvents , and the short circuit caused by the dendritic lithium deposits. Lithium Bis(fluorosulfonyl)imide salt has exhibited an impressive performance for lithium-dendrite suppression and cycling efficiency improving at low current densities. Here, we use LiNO 3 as the film-forming additive for further passivation of the Li metal anodes . Following the addition of LiNO 3 , the cycling performance of the cells with 2.5 M LiFSI-0.75 M LiNO 3 /DOL as electrolyte at high currents is improved obviously. The symmetrical lithium–metal cells can be cycled for 1000 cycles with more than 1000 h at 5 mA cm −2 with a stripping/plating capacity of 2 mAh cm −2 . Moreover, the Li/Cu cell could be cycled for 400 cycles with a stable and high average Coulombic efficiency (CE) of 98.8% at 3 mA cm −2 with a capacity of 2 mAh cm −2 . Besides, the electrolyte contains an well adaptability to the electrode of LiFePO 4 and improves the cycling stability of the lithium metal. Consequently, LiNO 3 demonstrates an excellent performance as a film-forming additive in the LiFSI/DOL electrolyte for further passivation of the Li metal anodes.