Department of Physics, Virginia Commonwealth University, Richmond, VA 23284.
Department of Physics, Virginia Commonwealth University, Richmond, VA 23284
Proc Natl Acad Sci U S A. 2017 Oct 17;114(42):11046-11051. doi: 10.1073/pnas.1704086114. Epub 2017 Oct 2.
Enjoying great safety, high power, and high energy densities, all-solid-state batteries play a key role in the next generation energy storage devices. However, their development is limited by the lack of solid electrolyte materials that can reach the practically useful conductivities of 10 S/cm at room temperature (RT). Here, by exploring a set of lithium-rich antiperovskites composed of cluster ions, we report a lithium superionic conductor, LiSBF, that has an estimated 3D RT conductivity of 10 S/cm, a low activation energy of 0.210 eV, a giant band gap of 8.5 eV, a small formation energy, a high melting point, and desired mechanical properties. A mixed phase of the material, LiS(BF)Cl, with the same simple crystal structure exhibits an RT conductivity as high as 10 S/cm and a low activation energy of 0.176 eV. The high ionic conductivity of the crystals is enabled by the thermal-excited vibrational modes of the cluster ions and the large channel size created by mixing the large cluster ion with the small elementary ion.
全固态电池具有极高的安全性、功率和能量密度，是下一代储能设备的关键组成部分。然而，其发展受到缺乏室温下实际有用电导率达到 10 S/cm 的固体电解质材料的限制。在这里，我们通过探索一组由簇离子组成的富锂反钙钛矿，报告了一种锂离子超导体 LiSBF，其估计的 3D RT 电导率为 10 S/cm，具有低的激活能 0.210 eV、巨大的带隙 8.5 eV、小的形成能、高的熔点和理想的机械性能。具有相同简单晶体结构的材料的混合相 LiS(BF)Cl 在 RT 电导率高达 10 S/cm 和低激活能 0.176 eV。晶体的高离子电导率是由簇离子的热激发振动模式和大簇离子与小单元离子混合所产生的大通道尺寸所实现的。
