Compressible and Elastic Reduced Graphene Oxide Sponge for Stable and Dendrite-Free Lithium Metal Anodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium metal batteries face challenges including dendritic lithium deposition, unstable solid-electrolyte interphase (SEI) formation, and significant volume changes during cycling.
• These issues hinder the practical application and long-term stability of high-energy-density lithium metal batteries.

Purpose of the Study:

• To develop a novel anode material that addresses the key limitations of lithium metal batteries.
• To enhance the safety, stability, and performance of lithium metal batteries through structural engineering of the anode.

Main Methods:

• Introduction of a compressible and elastic reduced graphene oxide sponge (rGO-S) as a host for lithium metal anodes.
• Electrochemical characterization of Li@rGO-S half-cells and symmetric cells, including cycling stability and overpotential measurements.
• Assembly and testing of Li@rGO-S||LiFePO4 (LFP) full cells to evaluate practical performance.

Main Results:

• The rGO-S anode effectively suppressed lithium dendrite growth and stabilized the SEI layer.
• Li@rGO-S symmetric cells demonstrated excellent cycling stability for over 1200 cycles with low overpotential.
• Full cells using Li@rGO-S anodes exhibited high specific capacity (150.3 mAh g⁻¹ at 1C), superior rate performance, and good capacity retention.

Conclusions:

• The compressible rGO-S structure accommodates volume changes, releases plating-induced stress, and preserves the SEI.
• This approach significantly improves the Coulombic efficiency, cycling stability, and overall performance of lithium metal batteries.
• The developed Li@rGO-S anode offers a promising strategy for advancing next-generation high-energy-density energy storage systems.