Inorganic solid‐state electrolytes (SSEs) play a vital role in high‐energy all‐solid‐state batteries (ASSBs). However, the current method of SSE preparation usually involves high‐energy mechanical ball milling and/or a high‐temperature annealing process, which is not suitable for practical application. Here, a facile strategy is developed to realize the scalable synthesis of cost‐effective aluminum‐based oxyhalide SSEs, which involves a self‐propagating method by the exothermic reaction of the raw materials. This strategy enables the synthesis of various aluminum‐based oxyhalide SSEs with tunable components and high ionic conductivities (over 10‐3 S cm‐1 at 25 °C) for different cations (Li+, Na+, Ag+). It is elucidated that the amorphous matrix, which mainly consists of various oxidized chloroaluminate species that provide numerous sites for smooth ion migration, is actually the key factor for the achieved high conductivities. The application of these aluminum‐based oxyhalide SSEs synthesized by our approach further pushes forward their practical application considering their easy synthesis, low cost, and low weight that ensures high‐energy‐density ASSBs.

中文翻译：

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铝基卤氧化物固态电解质的通用自蔓延合成

无机固态电解质（SSE）在高能全固态电池（ASSB）中发挥着至关重要的作用。然而，目前的SSE制备方法通常涉及高能机械球磨和/或高温退火过程，不适合实际应用。在这里，开发了一种简单的策略来实现经济高效的铝基卤氧化物SSE的可扩展合成，其中涉及通过原材料放热反应的自蔓延方法。该策略能够合成各种铝基卤氧化物 SSE，其成分可调，并且对不同阳离子（Li+、Na+、Ag+）具有高离子电导率（25°C 时超过 10-3 S cm-1）。研究表明，非晶态基质主要由各种氧化氯铝酸盐物质组成，为离子的顺利迁移提供了大量的位点，实际上是实现高电导率的关键因素。通过我们的方法合成的这些铝基卤氧化物SSE的应用进一步推动了它们的实际应用，因为它们易于合成、低成本和低重量，确保了高能量密度ASSB。