Promoting Mechanistic Understanding of Lithium Deposition and Solid-Electrolyte Interphase (SEI) Formation Using Advanced Characterization and Simulation Methods: Recent Progress, Limitations, and Future Perspectives

In recent years, due to its great promise in boosting the energy density of lithium batteries for future energy storage, research on the Li metal anode, as an alternative to the graphite anode in Li-ion batteries, has gained significant momentum. However, the practical use of Li metal anodes has been plagued by unstable Li (re)deposition and poor cyclability. Although tremendous efforts have been devoted to the stabilization of Li metal anodes, the mechanisms of electrochemical (re-)deposition/dissolution of Li and solid-electrolyte-interphase (SEI) formation remain elusive. This article highlights the recent mechanistic understandings and observations of Li deposition/dissolution and SEI formation achieved from advanced characterization techniques and simulation methods, and discusses major limitations and open questions in these processes. In particular, the authors provide their perspectives on advanced and emerging/potential methods for obtaining new insights into these questions. In addition, they give an outlook into cutting-edge interdisciplinary research topics for Li metal anodes. It pushes beyond the current knowledge and is expected to accelerate development toward a more in-depth and comprehensive understanding, in order to guide future research on Li metal anodes toward practical application.

Automated summary

In recent years, research on Li metal anodes as an alternative to graphite anodes in Li-ion batteries has gained significant attention due to its potential in boosting the energy density of lithium batteries. However, the practical use of Li metal anodes has been hindered by issues of unstable Li deposition and poor cyclability. This article discusses recent advances in understanding the mechanisms of Li deposition/dissolution and solid-electrolyte-interphase (SEI) formation through advanced characterization techniques and simulation methods. The limitations and open questions in these processes are also addressed, along with perspectives on future research and potential methods for obtaining new insights.