Lithium metal batteries are regarded as promising alternatives to lithium ion batteries due to their high specific capacity. However, lithium dendrite growth during cycling causes safety problem and rapid capacity loss. Here, we report a composite Li anode composed (LYF) of metallic Li and trace amounts (1–2 wt%) of two-dimensional YF_δ. The lithiophilic nature of YF_δ enables its homogeneous dispersion in metallic lithium. The LYF electrode exhibits lower resistance, higher chemical and mechanical stability, and longer cycle life compared to bare Li electrode due to uniform Li stripping and plating with YF_δ incorporation, which was confirmed by in-situ optical microscope observation. X-ray photoelectron spectroscopy reveals that LiF can in-situ form on the LYF electrode with reactions between Li and YF_δ during cycling. The spontaneous reactions are clarified by density functional theory calculations. A quasi-solid-state cell with LYF anode, LiFePO₄ cathode and cathode-supported solid electrolyte layer has been constructed with a soft interface constructed between Li anode and solid electrolyte by in-situ thermal polymerization. The cell shows a high initial discharge capacity of 147 mAh g⁻¹ at 0.5 C at 60 °C and sustains a stable cycling over 50 cycles with the in-situ formed LiF-rich layer and soft interface.

锂金属电池由于其高比容量而被认为是锂离子电池的有前途的替代品。但是，锂枝晶在循环过程中的生长会导致安全问题和容量快速下降。这里，我们报告的复合Li阳极的二维YF的金属Li和痕量（1-2重量％）组成（LYF）_δ。YF的lithiophilic性质_δ使得能够在金属锂其均匀分散。所述LYF电极表现出低电阻，较高的化学和机械稳定性，以及更长的循环寿命相比裸Li电极由于均匀栗汽提并用YF电镀_δ掺入，这通过原位光学显微镜观察证实。X射线光电子能谱显示，可以的LiF与Li和YF之间的反应的LYF电极原位形式_δ循环期间。自发反应通过密度泛函理论计算得以阐明。通过原位热聚合，构建了具有LYF阳极，LiFePO ₄阴极和阴极支撑的固体电解质层的准固态电池，并在Li阳极和固体电解质之间构建了软界面。该电池在60°C的0.5 C下显示出147 mAh g ^-1的高初始放电容量，并通过原位形成的富LiF层和软界面在50个循环中保持稳定的循环。