All-solid-state batteries (ASSB) are considered promising candidates for future energy storage and advanced electric mobility. When compared to conventional Li-ion batteries, the substitution of Li-ion conductive, flammable liquids by a solid electrolyte and the application of Li-metal anodes substantially increase safety and energy density. The solid electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) provides high Li-ion conductivity of about 10⁻³ S/cm and is considered a highly promising candidate for both the solid electrolyte-separator and the ionically conductive part of the all-solid state composite cathode, consisting of the cathode material, the solid electrolyte, and an electron conductor. Co-sintering of the composite cathode is a sophisticated challenge, because temperatures above 1000 °C are typically required to achieve the maximum ionic conductivity of LATP but provoke reactions with the cathode material, inhibiting proper electrochemical functioning in the ASSB. In the present study, the application of sintering aids with different melting points and their impact on the sinterability and the conductivity of LATP were investigated by means of optical dilatometry and impedance spectroscopy. The microstructure of the samples was analyzed by SEM. The results indicate that the sintering temperature can be reduced below 800 °C while maintaining high ionic conductivity of up to 3.6 × 10⁻⁴ S/cm. These insights can be considered a crucial step forward towards enable LATP-based composite cathodes for future ASSB.

中文翻译：

---

降低Li +导电Li1.3Al0.3Ti1.7（PO4）3陶瓷的烧结温度

全固态电池（ASSB）被认为是未来储能和先进电动交通的有希望的候选者。与常规锂离子电池相比，用固体电解质代替锂离子导电易燃液体，以及使用锂金属阳极大大提高了安全性和能量密度。固态电解质Li _1.3 Al _0.3 Ti _1.7（PO ₄）₃（LATP）提供约10 ^-3的高锂离子电导率S / cm，被认为是固体电解质分离器和全固态复合阴极的离子导电部分的极有希望的候选者，它由阴极材料，固体电解质和电子导体组成。复合阴极的共烧结是一项艰巨的挑战，因为通常需要高于1000°C的温度才能获得LATP的最大离子电导率，但会引起与阴极材料的反应，从而抑制了ASSB中的适当电化学功能。在本研究中，通过光学膨胀法和阻抗谱研究了不同熔点的烧结助剂的应用及其对LATP的可烧结性和电导率的影响。通过SEM分析样品的微观结构。^-4 S / cm。这些见解可以被认为是迈向为未来的ASSB启用基于LATP的复合阴极的关键一步。