Leung Kevin
Sandia National Laboratories, MS 1415, Albuquerque, NM 87185, USA.
Phys Chem Chem Phys. 2020 May 20;22(19):10412-10425. doi: 10.1039/c9cp06485k.
Density Functional Theory (DFT) calculations of electrode material properties in high energy density storage devices like lithium batteries have been standard practice for decades. In contrast, DFT modelling of explicit interfaces in batteries arguably lacks universally adopted methodology and needs further conceptual development. In this paper, we focus on solid-solid interfaces, which are ubiquitous not just in all-solid state batteries; liquid-electrolyte-based batteries often rely on thin, solid passivating films on electrode surfaces to function. We use metal anode calculations to illustrate that explicit interface models are critical for elucidating contact potentials, electric fields at interfaces, and kinetic stability with respect to parasitic reactions. The examples emphasize three key challenges: (1) the "dirty" nature of most battery electrode surfaces; (2) voltage calibration and control; and (3) the fact that interfacial structures are governed by kinetics, not thermodynamics. To meet these challenges, developing new computational techniques and importing insights from other electrochemical disciplines will be beneficial.
几十年来，在诸如锂电池等高能量密度存储设备中，对电极材料特性进行密度泛函理论（DFT）计算一直是标准做法。相比之下，电池中明确界面的DFT建模可以说缺乏普遍采用的方法，需要进一步的概念发展。在本文中，我们关注固-固界面，这种界面不仅在全固态电池中普遍存在；基于液体电解质的电池通常依赖电极表面的薄固态钝化膜来发挥作用。我们通过金属阳极计算来说明，明确的界面模型对于阐明接触电势、界面电场以及相对于寄生反应的动力学稳定性至关重要。这些例子强调了三个关键挑战：（1）大多数电池电极表面的“脏污”性质；（2）电压校准和控制；（3）界面结构受动力学而非热力学支配这一事实。为应对这些挑战，开发新的计算技术并引入其他电化学学科的见解将是有益的。
