Yao Yu-Xing, Wan Jing, Liang Ning-Yan, Yan Chong, Wen Rui, Zhang Qiang
Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
Key Laboratory of Molecular Nanostructure and Nanotechnology, Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
J Am Chem Soc. 2023 Apr 12;145(14):8001-8006. doi: 10.1021/jacs.2c13878. Epub 2023 Mar 29.
The solid electrolyte interphase (SEI) is regarded as the most important yet least understood component in Li-ion batteries. Considerable effort has been devoted to unravelling its chemistry, structure, and ion-transport mechanism; however, the nucleation and growth mode of SEI, which underlies all these properties, remains the missing piece. We quantify the growth mode of two representative SEIs on carbonaceous anodes based on classical nucleation theories and atomic force microscopy imaging. The formation of inorganic SEI obeys the mixed 2D/3D growth model and is highly dependent on overpotential, whereby large overpotential favors 2D growth. Organic SEI strictly follows the 2D instantaneous nucleation and growth model regardless of overpotential and enables perfect epitaxial passivation of electrodes. We further demonstrate the use of large current pulses during battery formation to promote 2D inorganic SEI growth and improve capacity retention. These insights offer the potential to tailor desired interphases at the nanoscale for future electrochemical devices.
固态电解质界面（SEI）被认为是锂离子电池中最重要但却最不为人所了解的组件。人们已经投入了大量精力来揭示其化学性质、结构和离子传输机制；然而，作为所有这些性质基础的SEI的成核和生长模式，仍然是缺失的一环。我们基于经典成核理论和原子力显微镜成像，对碳质阳极上两种代表性SEI的生长模式进行了量化。无机SEI的形成遵循二维/三维混合生长模型，并且高度依赖于过电位，即大过电位有利于二维生长。有机SEI无论过电位如何，都严格遵循二维瞬时成核和生长模型，并能够实现电极的完美外延钝化。我们进一步证明了在电池形成过程中使用大电流脉冲来促进二维无机SEI生长并提高容量保持率。这些见解为未来的电化学器件在纳米尺度上定制所需的界面提供了可能性。
