Improving the safety features of traditional Li-ion batteries having a flammable liquid electrolyte is one of the current challenges that scientists have been trying to overcome. Inorganic solid ionic conductors are promising option to replace the liquid electrolytes in Li-ion batteries because of their high temperature stability. But their poor ionic conductivity is one bottleneck that prevents them in a widespread use. In order to increase the ion conduction, the electrolytes should be as dense as possible since pores have no contribution to ionic conductivity. For densification assessments during sintering of Li₇La₃Zr₂O₁₂, one of the popular inorganic solid ion conductors in the field of all solid-state Li-ion batteries, the Archimedes density measurement technique has been widely used. However, the Archimedes density itself is not sufficient enough to enlighten the densification behavior of Li₇La₃Zr₂O₁₂ since closed porosities that are very common in Li₇La₃Zr₂O₁₂ microstructures cannot be wetted by the immersed liquid. In this study, a densification model which combines Archimedes density with radial shrinkage, dilatometer, and microstructure for more accurate assessment of Li₇La₃Zr₂O₁₂ densification was offered. Optical dilatometer results showed shrinkage initiation after 980 °C. Archimedes densities were initially increased from 4.24 to 4.76 g/cm³ at the early stages of sintering and then stayed constant at 4.76 g/cm³. On the other hand, radial shrinkage showed continual increase from 7.33 to 13.20% pointing out the linking of closed porosities and grain separation.

中文翻译：

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用于烧结所有固态锂离子电池的Li 7 La 3 Zr 2 O 12基固体电解质的新型致密化模型

改善具有可燃液体电解质的传统锂离子电池的安全性是科学家一直试图克服的当前挑战之一。无机固体离子导体因其高温稳定性而有望替代锂离子电池中的液体电解质。但是它们差的离子电导率是阻止其广泛使用的一个瓶颈。为了增加离子传导，电解质应该尽可能稠密，因为孔对离子传导性没有贡献。用于Li ₇ La ₃ Zr ₂ O ₁₂烧结过程中的致密化评估作为一种在所有固态锂离子电池领域中最受欢迎的无机固态离子导体，阿基米德密度测量技术已被广泛使用。然而，阿基米德密度本身不足以启发Li ₇ La ₃ Zr ₂ O ₁₂的致密化行为，因为在Li ₇ La ₃ Zr ₂ O ₁₂微结构中非常普遍的封闭孔隙不能被浸没液体润湿。在这项研究中，将阿基米德密度与径向收缩，膨胀计和微观结构相结合的致密化模型，可以更准确地评估Li ₇ La ₃ Zr ₂提供了O ₁₂致密化。光学膨胀​​仪的结果表明，在980°C后开始收缩。在烧结的早期阶段，阿基米德密度最初从4.24 g / cm ³增加到4.76 g / cm ³，然后保持恒定在4.76 g / cm ³。另一方面，径向收缩率显示出从7.33％到13.20％的连续增加，指出了封闭孔隙和晶粒分离的联系。