Induction/Inhibition Effect on Lithium Dendrite Growth by a Binary Modification Layer on a Separator.

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Lithium metal batteries (LMBs) face challenges from lithium dendrite growth, which can cause internal short circuits and battery failure.
• Separator integrity is crucial for preventing dendrite penetration and ensuring safe operation of LMBs.

Purpose of the Study:

• To design and evaluate a modified separator for lithium metal batteries that inhibits lithium dendrite growth.
• To investigate the in situ conversion of an InN thin layer into a protective composite layer during battery cycling.

Main Methods:

• Fabrication of a separator modified with an indium nitride (InN) thin layer.
• Electrochemical testing of the modified separator in lithium metal cells to assess lithium plating/stripping behavior.
• Analysis of the separator's surface and composition after cycling to identify the formed protective layers.

Main Results:

• The InN thin layer in situ converted into a dual-phase layer composed of lithium-indium (Li-In) alloy and lithium nitride (Li3N).
• Li-In alloy promoted lateral lithium growth, preventing dendrite penetration, while Li3N improved ion distribution at the anode/separator interface.
• The synergistic effect of the Li-In alloy and Li3N significantly improved the electrochemical performance and cycling stability of LMBs.

Conclusions:

• The InN-modified separator effectively suppresses lithium dendrite growth and enhances the safety and performance of lithium metal batteries.
• The facile and scalable nature of the separator modification process, suitable for roll-to-roll manufacturing, makes it promising for practical applications.