Free-standing Li_1.5Al_0.5Ti_1.5P₃O₁₂ electrolyte sheets with a thickness of 50–150 μm were prepared by tape casting followed by sintering at 850–1000 °C in air. While a sintering temperature of 850 °C was too low to achieve appreciable densification and grain growth, a peak relative density of 95% was obtained at 920 °C. At higher sintering temperatures, the microstructure changed from a bimodal grain size distribution towards exclusively large grains (> 10 μm), accompanied by a decrease in relative density (down to 86% at 1000 °C). In contrast, ionic conductivity increased with increasing sintering temperature, from 0.1 mS/cm at 920 °C to 0.3 mS/cm at 1000 °C. Sintering behavior was improved by adding 1.5% of amorphous silica to the slurry. In this way, almost full densification (99.8%) and an ionic conductivity of 0.2 mS/cm was achieved at 920 °C.

Mechanical characterization was carried out on the almost fully densified material, yielding elastic modulus and hardness values of 109 and 8.7 GPa, respectively. The fracture strength and Weibull modulus were also characterized. The results confirm that densification and reduction of grain size improve the mechanical properties.

独立的Li _1.5 Al _0.5 Ti _1.5 P ₃ O ₁₂通过流延铸造，然后在空气中在850-1000°C的温度下烧结，制备厚度为50-150μm的电解质片。虽然850°C的烧结温度太低，无法实现明显的致密化和晶粒长大，但在920°C时却获得了95％的峰值相对密度。在较高的烧结温度下，微观结构从双峰粒度分布变为仅大晶粒（> 10μm），同时相对密度降低（在1000°C时降至86％）。相反，离子电导率随烧结温度的升高而增加，从920°C的0.1 mS / cm到1000°C的0.3 mS / cm。通过向浆料中添加1.5％的无定形二氧化硅，可以改善烧结性能。以此方式，在920℃下实现了几乎完全的致密化（99.8％）和0.2mS / cm的离子电导率。

在几乎完全致密化的材料上进行了机械表征，得出的弹性模量和硬度值分别为109和8.7 GPa。还表征了断裂强度和威布尔模量。结果证实，致密化和减小晶粒尺寸改善了机械性能。