Cubic Li₇La₃Zr₂O₁₂ (c-LLZO) is considered as one of the promising electrolytes for all-solid-state lithium-ion batteries, owing to its high Li ionic conductivity and chemical stability against Li anode. The c-LLZO/Li interface, as a Li-ion transport structure which affects the charge-discharge cycle of Li metal batteries, remains to be fully understood at present, especially on the atomic-level. Here, we present a first-principles study to explore the stability of the c-LLZO/Li interface and Li transport across the c-LLZO/Li interface. The interaction between Li slab and c-LLZO slab is attractive, which is confirmed to be physical adsorption by the density of state. Some vacancies are introduced into the Li layer to release the local strain at the interface. There is negligible change in the interface energy with the introduction of vacancies, meaning the local strain has little effect on the stability of the interface. The diffusion energy barriers of Li across the c-LLZO/Li interface are in the range of 0.17 to 0.36 eV, which are greatly influenced by the local strain. Such low diffusion energy barriers indicate the c-LLZO/Li interface is in favor of fast lithium ion conduction.

立方Li ₇ La ₃ Zr ₂ O ₁₂（c-LLZO）由于其高的Li离子电导率和对Li阳极的化学稳定性而被认为是全固态锂离子电池的有前途的电解质之一。作为影响锂金属电池的充放电循环的锂离子传输结构，c-LLZO / Li界面目前尚待充分了解，尤其是在原子水平上。在这里，我们提出了一项第一性原理研究，以探索c-LLZO / Li界面的稳定性以及Li跨c-LLZO / Li界面的传输。Li平板和c-LLZO平板之间的相互作用是有吸引力的，这通过状态密度被证实是物理吸附。在Li层中引入了一些空位以释放界面处的局部应变。随着空位的引入，界面能的变化可忽略不计，意味着局部应变对界面的稳定性影响很小。Li在c-LLZO / Li界面上的扩散能垒在0.17至0.36 eV的范围内，这受局部应变的影响很大。这种低扩散能垒表明c-LLZO / Li界面有利于快速锂离子传导。