Incorporation of Embedded Protective Layers to Circumvent the Low LiNO3 Solubility Problem and Enhance Li Metal Anode Cycling Performance

Lithium nitrate (LiNO3) is attracting attention as a promising additive for dendrite suppression owing to its formation of Li3N during electrochemical decomposition and the formation of a spherical-like Li deposition morphology. However, LiNO3 has very low solubility in carbonate electrolytes, and it is continuously decomposed during cycling; thus, we infuse it into a ceramic composite protective layer coated on a thin Li metal surface (thickness: 20 mu m) to act as a reservoir during battery cycling. This allows for a slow release of LiNO3 into the electrolyte during cycling, the formation of a Li3N-infused solid electrolyte interface layer, and dendrite suppression. Here, this results in enhanced Li/ Li symmetric cell cycling performance for similar to 345 h at 0.5 mA cm-2 (0.25 mAh cm-2) and similar to 250 cycles, with similar to 96% initial discharge capacity retention and similar to 99% Coulombic efficiency for Li/LMO cells. Because of the facile nature and effectiveness of the process, the LiNO3 embedded protective layer has the potential to enhance the performance of thin Li metal anodes in Li metal batteries.

Automated summary

Lithium nitrate (LiNO3) is used as an additive for dendrite suppression. However, it has low solubility in carbonate electrolytes and is continuously decomposed during cycling. To address this, LiNO3 is infused into a ceramic composite protective layer to act as a reservoir, allowing for slow release during cycling and enhanced performance of thin Li metal anodes in Li metal batteries.