by Minghao Zhang, Karnpiwat Tantratian, So-Yeon Ham, Zhuo Wang, Mehdi Chouchane, Ryosuke Shimizu, Shuang Bai, Hedi Yang, Zhao Liu, Letian Li, Amir Avishai, Lei Chen, Ying Shirley Meng
The use of alkali metal anode in all-solid-state batteries has been very challenging, particularly under low stack pressures. While tremendous efforts have been made to investigate the morphology of alkali metals, such as lithium plating and dendrites, the texture remains rarely explored. The term “texture” refers to the grain orientation that is oriented in a particular direction instead of random distribution. Plasma-focused ion beam-electron backscatter diffraction (PFIB-EBSD) enables the characterization of the metal texture under various electrochemical plating and stripping conditions. The experimental observations are complemented with phase-field modeling built from the thermodynamic theory. This study highlights the competition of surface energy and strain energy for texture formation of alkali metals. Understanding how the atomic diffusion and surface energy of alkali metals dominate grain selection growth during electrochemical processes can explain the kinetic constraints of solid-state batteries using metal anodes, particularly at room temperature. Leveraging this mechanistic understanding, desirable textures can be achieved through interface engineering to improve the plating/stripping efficiency at high current densities.