Semi-Embedded Structured Bi Nanospheres for Boosted Self-Heating-Induced Healing of Li-Dendrites

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium metal anodes (LMAs) are crucial for high-energy-density batteries.
• Lithium dendrite growth remains a major safety and performance challenge.
• Self-heating-induced healing is a promising strategy to suppress dendrites.

Purpose of the Study:

• To develop a novel lithium-host material that promotes self-heating-induced healing of lithium dendrites.
• To investigate the mechanism of dendrite suppression using a bismuth nanosphere semi-buried carbon cloth (Bi-NS-CC).
• To evaluate the electrochemical performance of the developed composite anode.

Main Methods:

• Fabrication of a 3D flexible carbon cloth host decorated with ultrasmall bismuth nanospheres (Bi-NS-CC).
• Formation of a Li$_{3}$Bi alloy with molten lithium within the 3D host structure.
• Electrochemical testing of symmetric cells under high current densities and cycling conditions.

Main Results:

• The Bi-NS-CC material effectively guides uniform lithium deposition and forms a self-supporting composite anode.
• Self-heating of lithium dendrites at 10 mA cm$^{-2}$ is uniformly managed by the carbon cloth host and Bi nanospheres.
• Achieved ultra-long cycling of 1500 hours and ultra-low overpotential of 15 mV at 10 mA cm$^{-2}$/10 mAh cm$^{-2}$.

Conclusions:

• The Bi-NS-CC composite anode demonstrates superior mechanical properties and interfacial stability.
• The proposed material effectively suppresses lithium dendrites through self-heating-induced healing under harsh conditions.
• This work presents a viable strategy for designing robust lithium metal anodes for next-generation batteries.