A mild and efficient closed-loop recycling strategy for spent lithium-ion battery

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Rising demand for lithium-ion batteries necessitates efficient recycling of spent materials.
• Current methods for recovering lithium and other valuable metals from ternary cathodes face challenges in efficiency and cost.

Purpose of the Study:

• To develop a closed-loop recovery process for spent ternary cathode materials.
• To achieve efficient lithium extraction and direct regeneration of valuable metals.

Main Methods:

• Sulfur-assisted roasting of spent LiNi_xCo_yMn_1-x-yO₂ (NCM) cathode materials at 500 °C.
• Selective transformation of lithium to Li₂SO₄.
• Regeneration of ternary leaching residues into R-NCM cathode materials.

Main Results:

• Achieved 98.91% lithium leaching extraction rate.
• Preserved the morphology and purity of NiCoMn-based oxide residue.
• Regenerated R-NCM material demonstrated good discharge capacity (144.3 mA·h/g at 1 C) and 80% capacity retention after 150 cycles.

Conclusions:

• The sulfur-assisted roasting method provides an efficient and environmentally friendly pyrometallurgical pathway for closed-loop recovery of spent lithium-ion batteries.
• This process facilitates the direct regeneration of high-value NCM cathode materials from ternary leaching residues.