The use of solid-state electrolytes (SSEs) within batteries is a promising strategy to safely access the high capacity of lithium metal anodes. However, most SSEs with practical ionic conductivity are chemically unstable in contact with lithium metal, which is detrimental to battery performance. Lithium aluminum germanium phosphate (LAGP) is an SSE with high ionic conductivity (10⁻⁴-10⁻³ S cm⁻¹) and good environmental stability, but it forms an amorphous interphase region that continuously grows in contact with Li, leading to chemo-mechanical failure within solid-state batteries. Here, we find that thin (∼30 nm) chromium interlayers deposited between the lithium electrode and LAGP extend cycle life to over 1000 h at moderate current densities (0.1–0.2 mA cm⁻²), compared to ∼30 h without protection. This significantly improved stability occurs because the metallic interlayer alters the trajectory of interphase formation and the nature of the electrochemical reaction at the interface. This work shows the promise of interface engineering for a variety of SSE materials within solid-state batteries, while emphasizing the necessity of understanding how protection layers affect dynamic evolution of interfaces.

中文翻译：

---

金属保护层如何延长基于NASICON的固态锂电池的寿命

在电池中使用固态电解质（SSE）是一种有前景的策略，可以安全地使用高容量的锂金属阳极。但是，大多数具有实用离子导电性的SSE在与锂金属接触时在化学上不稳定，这对电池性能有害。磷酸锂铝锗（LAGP）是具有高离子电导率（10 ^-4 -10 ^-3 S cm ^-1）和良好的环境稳定性的SSE ，但它形成无定形的中间区域，与Li接触连续生长，导致化学反应-固态电池内的机械故障。在这里，我们发现在中等电流密度（0.1–0.2 mA cm^-2），相比之下，没有保护的〜30 h。由于金属夹层改变了相形成的轨迹和界面处的电化学反应的性质，因此显着提高了稳定性。这项工作显示了固态电池中各种SSE材料的界面工程的前景，同时强调了了解保护层如何影响界面动态演变的必要性。