Swift Michael W, Swift James W, Qi Yue
Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, USA.
Department of Mathematics and Statistics, Northern Arizona University, Flagstaff, AZ, USA.
Nat Comput Sci. 2021 Mar;1(3):212-220. doi: 10.1038/s43588-021-00041-y. Epub 2021 Mar 25.
Models of the electrical double layer (EDL) at electrode/liquid-electrolyte interfaces no longer hold for all-solid-state electrochemistry. Here we show a more general model for the EDL at a solid-state electrochemical interface based on the Poisson-Fermi-Dirac equation. By combining this model with density functional theory predictions, the interconnected electronic and ionic degrees of freedom in all-solid-state batteries, including the electronic band bending and defect concentration variation in the space-charge layer, are captured self-consistently. Along with a general mathematical solution, the EDL structure is presented in various materials that are thermodynamically stable in contact with a lithium metal anode: the solid electrolyte LiLaZrO (LLZO) and the solid interlayer materials LiF, LiO and LiCO. The model further allows design of the optimum interlayer thicknesses to minimize the electrostatic barrier for lithium ion transport at relevant solid-state battery interfaces.
电极/液体电解质界面处的双电层（EDL）模型不再适用于全固态电化学。在此，我们基于泊松-费米-狄拉克方程展示了一种用于固态电化学界面处双电层的更通用模型。通过将该模型与密度泛函理论预测相结合，全固态电池中相互关联的电子和离子自由度，包括空间电荷层中的电子能带弯曲和缺陷浓度变化，得以自洽地捕捉。连同一般数学解一起，在与锂金属阳极接触时热力学稳定的各种材料中呈现了双电层结构：固体电解质LiLaZrO（LLZO）以及固体中间层材料LiF、LiO和LiCO。该模型还允许设计最佳中间层厚度，以最小化相关固态电池界面处锂离子传输的静电势垒。
