Architecture-Controlled Hierarchical Carbon-Based Current Collector for Mitigating Interfacial Instabilities in...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium metal batteries are crucial for high-energy-density storage but face challenges like lithium dendrite growth and interfacial reactions.
• Commercialization of lithium metal batteries is hindered by safety and stability issues related to lithium metal anodes.

Purpose of the Study:

• To develop an architecture-controlled, hierarchically porous carbon-based current collector for lithium metal batteries.
• To suppress dendritic lithium growth and interfacial instabilities at the lithium metal anode.
• To enhance the safety and performance of high-energy-density rechargeable batteries.

Main Methods:

• Fabrication of a carbon current collector using carbon nanotubes and activated carbon black with controlled defects.
• Utilizing scanning electron microscopy (SEM) for analyzing lithium nucleation sites.
• Conducting electrochemical characterization, including capacity retention and Coulombic efficiency measurements at 2C.

Main Results:

• The carbon current collector exhibits a lightweight architecture (0.69 mg cm⁻²) with controlled defects acting as lithiophilic nucleation sites.
• The collector ensures efficient electron transport and uniform Li-ion flux, confining lithium nucleation within the porous matrix.
• Electrochemical tests showed capacity retention of 50.4% at 2C, 77.6% over extended cycling, and an average Coulombic efficiency of 96.2%.

Conclusions:

• The proposed architecture-controlled carbon current collector effectively suppresses dendrite formation and interfacial instabilities in lithium metal anodes.
• This scalable strategy enhances the stability of lithium metal anodes, paving the way for safer, high-energy-density batteries.
• The developed current collector is suitable for demanding applications such as electric mobility and aerospace systems.