Sub-project 4.2

Design and synthesis of high Ni-containing NCM cathode materials by using the recovered and refined Li/Co/Ni/Mn salts.

Theme 3 + 4

To further increase the value of recovered materials, we will use these recovered and refined Li/Co/Ni/Mn salts to synthesise new cathode materials. Considering the high cost of Co and low capacity/voltage of LiCoO2, the battery industry will adopt the high Ni-containing NCM cathode materials such as the NCM811 or NCM92 to increase the energy density and sustainability of current Li-ion batteries. Therefore, NCM811 or NCM92 will be synthesised by using the recovered and refined Li/Co/Ni/Mn salts as the precursors. Strategies such as elemental doping, surface coating, and microstructural modifications will be used to make that the recovered cathode material has equal or, in some instances, better electrochemical performance compared with commercial cathode materials.

Sub-project 4.3

Separate and regenerate the single cathode materials from black mass with high electrochemical performance.

Theme 3 + 4

Direct recycling is an ideal recycling process that seeks to reconstitute or repair deficient components of materials without destroying them, which could maximize recycling efficiency while minimizing adverse environmental impacts. But direct recycling is mainly conducted in the laboratory due to the multiplicity of battery chemistries, and because single-cathode input is preferred to recover high-quality cathode powder. The black mass may contain mixed cathode materials with multiplicity of chemistries, making it difficult to be regenerated via direct recycling method.

In this project, we will harness and advance scalable froth flotation to efficiently separate the different cathodes from each other in black mass. It is expected that the separation of different cathode materials from each other can be separated by froth flotation because of their difference in surface hydrophilicity. A systematic investigation will be performed to tune the surface properties of the electrode materials to enhance separation. Furthermore, the separated individual cathode will be further regenerated to achieve high electrochemical performance. Upgrading a cathode material by chemically redesigning its composition to reflect the stoichiometry of more desirable cathode formulations will be also explored to increase the economic value.