Department of Applied Physics, Stanford University, Stanford, California 94305, United States.
Department of Materials Science & Engineering, Stanford University, Stanford, California 94305, United States.
Aionics, Inc., Evanston, Wyoming 82930, United States.
Department of Chemistry, Stanford University, Stanford, California 94305, United States.
Google Brain, Mountain View, California 94043, United States.
Solid Power, Inc., Louisville, Colorado 80027, United States.
我们报告了一种固态锂离子电解质，该电解质有望同时展现出快速的离子电导率，宽的电化学稳定性，低成本和低质量密度。我们报告了基于出色的密度泛函理论（DFT）的室温单晶锂-硼-硫（Li-BS）体系中两相的室温离子电导率值：62（+9，-2）mS cm
-1
在李
5
乙
7
小号
13
和80（-56，-41）。MS厘米
-1
的Li
9
乙
19
š
33
。我们报告了两个附加相的重要离子电导率值：在Li
2
B
2
S中为0.0056至0.16 mS / cm
–1
之间
Li
3
BS
3中为
5
和0.0031至9.7 mS cm
–1之间
，具体取决于所使用的室温外推方案。据我们所知，我们的预测使Li
9
B
19
S
33
和Li
5
B
7
S
13
成为任何晶体材料的DFT计算的单晶离子电导率的第二和第三高。我们计算出这些材料的热力学电化学稳定性窗口宽度对于Li
5
B
7
S
13
为0.50 V，对于Li
2
B
2
S
5
为0.16 V，对于Li为0.45 V
3
BS
3
和0.60 V的Li
9
B
19
S
33
。与包括Li
10
GeP
2
S
12
（LGPS）在内的最著名的基于硫化物的固态锂离子电解质材料相比，这些材料分别具有相似或更好的离子电导率和电化学稳定性。但是，我们预测，由Li–B–S系统中的各种成分合成的电解质材料可能会显示出更宽的0.63 V的热力学电化学稳定性窗口，并可能高达3 V或更高。Li–B–S系统的基本成本也很低，约为0.05 USD / m
2
每10μm厚度，明显低于含锗LGPS的厚度，并且质量密度低于2 g / cm
3
。这些快速传导阶段最初是通过基于机器学习的方法来筛选12,000多种固体电解质候选物而引起我们注意的，此处提供的证据表明该模型取得了令人鼓舞的成功。
We report a solid-state Li-ion electrolyte predicted to exhibit simultaneously fast ionic conductivity, wide electrochemical stability, low cost, and low mass density. We report exceptional density functional theory (DFT)-based room-temperature single-crystal ionic conductivity values for two phases within the crystalline lithium–boron–sulfur (Li–B–S) system: 62 (+9, −2) mS cm
–1
in Li
5
B
7
S
13
and 80 (−56, −41) mS cm
–1
in Li
9
B
19
S
33
. We report significant ionic conductivity values for two additional phases: between 0.0056 and 0.16 mS/cm
–1
in Li
2
B
2
S
5
and between 0.0031 and 9.7 mS cm
–1
in Li
3
BS
3
depending on the room-temperature extrapolation scheme used. To our knowledge, our prediction gives Li
9
B
19
S
33
and Li
5
B
7
S
13
the second and third highest reported DFT-computed single-crystal ionic conductivities of any crystalline material. We compute the thermodynamic electrochemical stability window widths of these materials to be 0.50 V for Li
5
B
7
S
13
, 0.16 V for Li
2
B
2
S
5
, 0.45 V for Li
3
BS
3
, and 0.60 V for Li
9
B
19
S
33
. Individually, these materials exhibit similar or better ionic conductivity and electrochemical stability than the best-known sulfide-based solid-state Li-ion electrolyte materials, including Li
10
GeP
2
S
12
(LGPS). However, we predict that electrolyte materials synthesized from a range of compositions in the Li–B–S system may exhibit even wider thermodynamic electrochemical stability windows of 0.63 V and possibly as high as 3 V or greater. The Li–B–S system also has a low elemental cost of approximately 0.05 USD/m
2
per 10 μm thickness, which is significantly lower than that of germanium-containing LGPS, and a comparable mass density below 2 g/cm
3
. These fast-conducting phases were initially brought to our attention by a machine learning-based approach to screen over 12,000 solid electrolyte candidates, and the evidence provided here represents an inspiring success for this model.
