Traditional recycling of lithium-ion battery cathode materials draws the most attention currently due to the valuable metal elements contained, especially cobalt. There are three dominate recycling approaches that may be used to recover useful materials from the aged cathode powders: pyrometallurgical, hydrometallurgical and direct physical.(1-3) The former two methods are already operating at scale. However, they suffer from significant energy input and complex chemical process respectively, which makes the recycled products less environmental-friendly and economically competitive. Recently, processing methods have been developed with less energy and cost input by making directly recycling the cathode material for reuse in a new battery. This is appealing in cases where there is a large amount of identical or very similar cathode materials in use. (2, 4)

In this work, we show “direct recycled” products of differently cycled Li(Ni_xCo_yAl_z)O₂ cathode via a solid-state processing method with different parameters. We assess the materials product performance in terms of electrochemical specific capacity, phase purity and consistency. Furthermore, we correlated interaction among aged conditions of cathode, solid-state process parameters and recycled product performance. Figure 1 shows that when treated with the same solid-state process parameters, the recycled cathode materials show different electrochemical performance depending on conditions of the aged cathode materials.

In this talk, we will discuss our approach and results, as well as suggest a technical path forward for the implementation of large-scale direct recycling of cathode materials from aged lithium-ion batteries.

Reference:

1. L. Gaines, Sustain Mater Techno, 17 (2018).
2. H. Wang, S. Frisco, E. Gottlieb, R. Yuan and J. F. Whitacre, J Power Sources, 426, 67 (2019).
3. R. E. Ciez and J. F. Whitacre, Nat Sustain, 2, 148 (2019).
4. H. Wang and J. F. Whitacre, Energy Technol-Ger, 6, 2429 (2018).