A novel three-step approach to separate cathode components for lithium-ion battery recycling

Lithium-ion batteries (LIBs) represent efficient energy storage technology that can help to alleviate fossil fuel-based CO2 emissions. Presently, LIBs are being applied extensively in consumer electronics and electric vehicles, but because of limited resources, there is an urgent need for spent LIB recycling technologies. The complexity of LIBs, especially the electrode part, makes it difficult to achieve precision separations for each single component from the used electrode with low emissions. Herein, we propose a three-step treatment for the separation of cathode components. In detail, detaching of the current collector from the cathode is accomplished by the solvent method, which was found to be an ideal strategy compared with previous reports. Then, a thermal treatment is used to remove the polymer binder in the second step because we demonstrated that it is challenging to separate polyvinylidene fluoride (PVDF) from other cathode components by dissolution with N-methylpyrrolidone. The separation efficiency between the active material and conductive carbon by the polymer solution in the third step showed reasonably good results. We anticipate this work will serve as an important reference for the separation of each single electrode component in both laboratory- and industrial-scale applications. Separation of binder and development of novel binders, which can be easily recycled for sustainable LIBs, are fruitful areas for further research.