The cycling stability of high-energy-density lithium (Li) metal batteries is severely hindered by uneven Li deposition, which is caused by the heterogeneous transport of Li ions in solid electrolyte interphase (SEI) on the surface of Li metal anodes. LiF-rich SEI emerges as a promising solution to improve homogeneous transport of Li ions. Herein, constructing LiF-rich SEI by regulating the interaction between the polymer coating on Li metal anode and fluoroethylene carbonate (FEC) in electrolytes was demonstrated. The polymer coating with uniformly distributed polar functional groups can interact with intermediate decomposition products of FEC, promoting the formation of LiF. LiF-rich SEI ensures improved uniformity of Li deposition, which promises stable operation of Li metal batteries under practical conditions for 143 cycles in comparison with 89 cycles of control group. Moreover, a prototype pouch cell of 1.0 Ah maintains a capacity retention of 90% after 180 cycles. This work provides a fresh attempt to construct LiF-rich SEI by regulating the interaction between solvent and polymer for long-cycling Li metal batteries.

高能量密度锂 (Li) 金属电池的循环稳定性受到不均匀的锂沉积的严重阻碍，这是由锂离子在锂金属负极表面的固体电解质界面 (SEI) 中的非均匀传输引起的。富含 LiF 的 SEI 作为改善锂离子均匀传输的有前途的解决方案而出现。在此，证明了通过调节锂金属负极上的聚合物涂层与电解质中的氟代碳酸亚乙酯 (FEC) 之间的相互作用来构建富含 LiF 的 SEI。具有均匀分布的极性官能团的聚合物涂层可以与FEC的中间分解产物相互作用，促进LiF的形成。富含 LiF 的 SEI 可确保提高 Li 沉积的均匀性，与对照组的 89 个循环相比，这保证了锂金属电池在实际条件下稳定运行 143 个循环。此外，1.0 Ah 的原型软包电池在 180 次循环后仍保持 90% 的容量保持率。这项工作通过调节长循环锂金属电池中溶剂和聚合物之间的相互作用，为构建富含 LiF 的 SEI 提供了一种新的尝试。