Anode-less sodium–metal batteries (SMBs) with high theoretical capacity and low cost are promising candidates for next-generation rechargeable batteries. However, the poor cyclability resulting from uneven Na deposition with unstable solid electrolyte interphase (SEI) and accumulative dead sodium has severely impeded their practical use. This work proposed a simple strategy, that is, coating current collector with Ketjenblack, which could maintain good cycling stability in anode-less SMBs. Moreover, in situ EPR (electron paramagnetic resonance) imaging reveals that the Ketjenblack coating can not only facilitate the homogeneous Na deposition but also eliminate nonuniformity of Na deposits exhibiting progressive self-leveling behavior during repeated sodium plating/stripping.

中文翻译：

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原位 EPR 成像揭示渐进式自流平沉积可提高无阳极钠金属电池的循环性能

具有高理论容量和低成本的无阳极钠金属电池（SMB）是下一代可充电电池的有希望的候选者。然而，钠沉积不均匀、不稳定的固体电解质界面（SEI）和累积的死钠导致循环性能差，严重阻碍了其实际应用。这项工作提出了一个简单的策略，即用 Ketjenblack 涂覆集流体，这可以在无阳极 SMB 中保持良好的循环稳定性。此外，原位 EPR（电子顺磁共振）成像表明，Ketjenblack 涂层不仅可以促进均匀的 Na 沉积，还可以消除 Na 沉积的不均匀性，在重复镀钠/剥离过程中表现出渐进的自流平行为。