Preparation of single-crystal ternary cathode materials via recycling spent cathodes for high performance lithium-ion batteries

With the rapid consumption of lithium-ion batteries (LIBs), the recycling of spent LIBs is becoming imperative. However, the development of effective and environmentally friendly methods towards the recycling of spent LIBs, especially waste electrode materials, still remains a great challenge. Herein, on the basis of a Li-based molten salt, we have developed a facile and effective strategy to recycle spent polycrystalline ternary cathode materials into single-crystal cathodes. The regenerated plate-like single-crystal LiNi0.6Co0.2Mn0.2O2 material with exposed {010} planes achieves an excellent rate performance and outstanding cycling stability. In particular, a high capacity of 155.1 mA h g(-1) and a superior capacity retention of 94.3% can be achieved by the recycled cathode material even after 240 cycles at 1 C. Meanwhile the single-crystal structure can be well reserved without any cracks or pulverization being observed. Moreover, this recycling method can be expanded to recycle other waste Ni-Co-Mn ternary cathode materials (NCM) or their mixtures for producing high-performance single-crystal cathode materials, demonstrating its versatility and flexibility in practical applications. Therefore, the strategy of converting spent NCM cathodes into single-crystal ones with satisfactory electrochemical performance may open up a cost-effective pathway for resolving the issues caused by the large amounts of spent LIBs, thus facilitating the sustainable development of LIBs.

Automated summary

This study proposes a facile and effective strategy to recycle spent electrode materials into single-crystal cathodes using a Li-based molten salt. The regenerated single-crystal cathode material exhibits excellent electrochemical performance and cycling stability, making it suitable for producing high-performance cathode materials. The versatility and flexibility of this strategy are demonstrated by its ability to recycle various waste Ni-Co-Mn ternary cathode materials. This approach contributes to the sustainable development of lithium-ion batteries by addressing the issues caused by the large amounts of spent batteries.