Gombotz Maria, Rettenwander Daniel, Wilkening H Martin R
Institute for Chemistry and Technology of Materials, Technical University of Graz, Graz, Austria.
ALISTORE-European Research Institute, CNRS FR3104, Hub de l'Energie, Amiens, France.
Front Chem. 2020 Feb 25;8:100. doi: 10.3389/fchem.2020.00100. eCollection 2020.
Currently, a variety of solid Li conductors are being discussed that could potentially serve as electrolytes in all-solid-state Li-ion batteries and batteries using metallic Li as the anode. Besides oxides, sulfides and thioposphates, and also halogenides, such as LiYBr, belong to the group of such promising materials. Here, we report on the mechanosynthesis of ternary, nanocrystalline (defect-rich) Li[In Li ]Br, which crystallizes with a spinel structure. We took advantage of a soft mechanochemical synthesis route that overcomes the limitations of classical solid-state routes, which usually require high temperatures to prepare the product. X-ray powder diffraction, combined with Rietveld analysis, was used to collect initial information about the crystal structure; it turned out that the lithium indium bromide prepared adopts cubic symmetry ( ). The overall and electronic conductivity were examined via broadband conductivity spectroscopy and electrical polarization measurements. While electric modulus spectroscopy yielded information on long-range ion transport, Li nuclear magnetic resonance (NMR) spin-lattice relaxation measurements revealed rapid, localized ionic hopping processes in the ternary bromide. Finally, we studied the influence of thermal treatment on overall conductivity, as the indium bromide might find applications in cells that are operated at high temperatures (330 K and above).
目前，人们正在讨论各种固态锂导体，它们有可能在全固态锂离子电池以及以金属锂为阳极的电池中用作电解质。除了氧化物、硫化物和硫代磷酸盐之外，卤化物，如LiYBr，也属于这类有前景的材料。在此，我们报道了具有尖晶石结构的三元纳米晶（富含缺陷）Li[In Li ]Br的机械合成。我们利用了一种软机械化学合成路线，该路线克服了传统固态路线的局限性，传统固态路线通常需要高温来制备产物。结合Rietveld分析的X射线粉末衍射被用于收集有关晶体结构的初始信息；结果表明，所制备的锂铟溴化物具有立方对称性（ ）。通过宽带电导率光谱和电极化测量来研究整体电导率和电子电导率。虽然电模量光谱提供了关于长程离子传输的信息，但锂核磁共振（NMR）自旋晶格弛豫测量揭示了三元溴化物中快速的局域离子跳跃过程。最后，我们研究了热处理对整体电导率的影响，因为溴化铟可能会应用于在高温（330 K及以上）下运行的电池中。
