Enhancing Lithium Metal Anode Stability through Surface Modification and Heat Treatment for 3D Current Collectors.

Lithium (Li) metal anodes (LMAs) offer the promise of achieving realistic high-energy-density batteries capable of meeting consumer demands for electric vehicles with a long driving range per charge. However, dendrite formation during Li plating is one of the main challenges that prevents the practical deployment of LMAs. Here, we focus on the Cu current collector (CC)-Li interface and mainly on the modification of the CC surfaces with a lithiophilic coating that has high affinity toward Li deposition. Previous research showed that indium is a potential candidate for preventing lithium dendrite growth. We propose a simple, cost-effective, and scalable solution to enhance the lithiophilicity of Cu current collectors. Indium films were grown electrochemically on Cu three-dimensional CC (3DCC) surfaces and then annealed at 450 °C for 2 h. The unannealed and annealed In coatings both showed a dendrite-free Li morphology and low surface area Li deposits. The electrochemical performances of unannealed and annealed coatings were studied in both symmetric and anode-free cells, all of which exhibited longer cycling stability compared with LMAs utilizing bare Cu 3DCCs.