Battery recycling process are many and varied depending on many factors. However, in all of these the key aim is to recover high quality materials at the lowest possible cost/impact. We should also note that for a battery pack this is the last step in the 4R’s (Repair, Reman, Repurpose, Recycle) as we should first of all extract as much economic use from the pack as possible.
The fundamental steps are:
- Sorting: batteries are categorized by type and chemistry.
- Dismantling: where possible parts are separated, eg busbars
- Shredding: batteries are broken down into smaller pieces to make it easier to separate the different components. This could include mechanically peeling the anode and cathode layers apart.
- Material Recovery: at this stage a number of alternative methods are used:
- Hydrometallurgical: Batteries are ground up and dissolved in acid, then chemicals are used to extract recyclable elements.
- Pyrometallurgical: Batteries are melted at high temperatures to extract recyclable materials.
- Direct recycling: Batteries are taken apart, ground up, and materials are recovered from the ground waste.
- Electro-hydrometallurgy: An electric current is applied to a leaching solution to extract valuable metals. This method is more efficient and sustainable than traditional methods.
- Purification: depending on the above process the metals are further purified to remove impurities.
- Disposal: The remaining materials, such as toxic substances and acid, are disposed of in accordance with local, state, and federal regulations.
- Reuse: The pure metals are sold to manufacturers to make new batteries and other products.
References
- ReLiB: Recycling and Reuse of EV Lithium-ion Batteries, The Faraday Institution
See also: Recycling Companies, Urban Mining, Automated Robotic Pack Disassembly, Direct Cathode Recycling, Battery Recycling: A Need of the hour, Electric Vehicles Forecasting – Part 1, Black Mass
Related: For process temperatures, recovery-route trade-offs, and how chemistry choice sets black mass value, see the deeper engineering companion, Recycling Process Engineering.