Garnet-type Li₇La₃Zr₂O₁₂ (LLZO) is among the most attractive candidates for achieving solid-state lithium batteries. LLZO pellets with high density are preferred because of their potential to prevent dendritic Li growth and penetration. However, the presence of pores inside the LLZO electrolyte is inevitable if it is prepared by a traditional solid-state reaction. Large numbers of pores have an adverse influence on both the ionic conductivity and density of the LLZO pellets. In this work, we studied the origin of pore formation in Li_6.4La₃Zr_1.4Ta_0.6O₁₂ (LLZTO) and introduced a fast oxygen-assisted sintering method to eliminate the pores. All of the basic physical properties of the LLZTO sintered in oxygen for only 1 h are better than those of the LLZTO sintered in air. The conductivity and Vickers hardness of the LLZTO increased to 6.13 × 10^–4 S cm^–1 and 9.82 GPa, corresponding to 12.3% and 62.8% enhancement, respectively, even at a low precalcined temperature of 600 °C. A Li||Li symmetric cell with the LLZTO sintered in oxygen also showed more stable and longer cycling at a higher current density (0.4 mA cm^–2).

中文翻译：

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一种简单高效的高密度石榴石型LLZTO固态电解质的方法。

石榴石型Li ₇ La ₃ Zr ₂ O ₁₂（LLZO）是实现固态锂电池最有吸引力的候选材料之一。优选具有高密度的LLZO粒料，因为它们具有防止树枝状锂生长和渗透的潜力。但是，如果通过传统的固态反应制备，则LLZO电解质内部不可避免地存在孔。大量的孔对LLZO颗粒的离子电导率和密度都有不利影响。在这项工作中，我们研究了Li _6.4 La ₃ Zr _1.4 Ta _0.6 O ₁₂中孔形成的起源。（LLZTO）并引入了一种快速的氧气辅助烧结方法来消除气孔。在氧气中烧结仅1小时的LLZTO的所有基本物理性能都比在空气中烧结的LLZTO的所有基本物理性能都要好。LLZTO的电导率和维氏硬度分别增加到6.13×10 ^–4 S cm ^–1和9.82 GPa，即使在600°C的低预煅烧温度下也分别增加了12.3％和62.8％。LLZTO在氧气中烧结的Li || Li对称电池在更高的电流密度（0.4 mA cm ^–2）下也显示出更稳定和更长的循环。