The performance of the lithium (Li) metal anode in rechargeable batteries has been hampered by the formation of unstable solid-electrolyte interphase layers, which compromise cycle life and pose significant safety concerns. Herein, for the first time, the anodizing oxidation of pure Li in a liquid electrolyte is developed by using tetrahydrofuran with LiNO₃. With this novel process, thickness-controllable Li oxide films with in situ nitrogen doping during the anodizing process can be obtained. The resulting nitrogen-doped Li oxide film (NLO) exhibits a uniform surface of the Li metal anode, effectively suppressing Li dendrite growth and simultaneously improving Li ionic conductivity. In addition, the Li metal full cells with Li/NLO anodes perform a long stable life of 1100 cycles at 5C. More importantly, this work demonstrates the great potential of NLO films as a solid-state electrolyte in solid-state Li metal batteries. The symmetric Li cells with NLO films perform excellent cycling stability for 300 h at 2 mA cm⁻² current density and high Li⁺ ion conductivity of ≈3 ×10⁻⁴ S cm⁻¹ at room temperature. This research not only provides a novel Li anodizing process and a stable Li metal anode but also opens up new possibilities for new solid-state Li metal battery technologies.

中文翻译：

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氮掺杂阳极氧化锂薄膜作为坚固的锂金属阳极和固态电解质

可充电电池中锂（Li）金属阳极的性能因不稳定的固体电解质中间相层的形成而受到阻碍，这会损害循环寿命并带来重大的安全问题。在此，首次通过使用四氢呋喃和LiNO ₃开发了液体电解质中纯Li的阳极氧化。通过这种新颖的工艺，可以在阳极氧化过程中获得具有原位氮掺杂的厚度可控的氧化锂薄膜。所得的氮掺杂氧化锂薄膜（NLO）呈现出均匀的锂金属负极表面，有效抑制了锂枝晶的生长，同时提高了锂离子电导率。此外，采用Li/NLO阳极的锂金属全电池在5C下具有1100次循环的长稳定寿命。更重要的是，这项工作展示了NLO薄膜作为固态锂金属电池中固态电解质的巨大潜力。具有NLO薄膜的对称Li电池在2 mA cm ^-2电流密度下表现出优异的300小时循环稳定性，并且在室温下表现出约3×10 ^-4 S cm ^{-1的高Li +}离子电导率。这项研究不仅提供了一种新颖的锂阳极氧化工艺和稳定的锂金属负极，而且为新型固态锂金属电池技术开辟了新的可能性。