Deciphering the Dynamic Processes at the Electrode-Electrolyte Interface for Stable Deposition of Lithium

Area of Science:

• Electrochemistry
• Materials Science
• Battery Technology

Background:

• Lithium-metal (Li) batteries face challenges with Li dendrite formation, causing short circuits and reduced efficiency.
• The solid electrolyte interphase (SEI) layer and electrolyte properties significantly impact Li deposition behavior.

Purpose of the Study:

• To precisely delineate the dynamic processes and interfacial properties of Li-metal electrodes in ether electrolytes.
• To understand the interplay between SEI characteristics and deposition kinetics in controlling Li growth.

Main Methods:

• Investigated Li-metal electrodes in representative ether electrolytes.
• Analyzed the influence of SEI homogeneity and deposition kinetics on Li morphology.
• Explored strategies for kinetic tuning and SEI design to control Li deposition.

Main Results:

• Homogeneous SEI with slow kinetics promotes layer-by-layer Li growth.
• Inhomogeneous SEI and fast kinetics lead to dendritic Li growth.
• Homogeneous SEI is not essential if kinetics are tuned; stable interfaces can be achieved with designed SEI.

Conclusions:

• The study clarifies the distinct roles of SEI and deposition kinetics in Li deposition.
• Findings provide crucial insights for designing advanced electrolytes to suppress Li dendrites and enhance battery performance.