Removal of Aluminum Foil from Lithium-ion Battery Cathode in the Recycling Process
Session Number
Project ID: ENGN 01
Advisor(s)
Dr. Mark Carlson; Illinois Mathematics and Science Academy
Discipline
Engineering
Start Date
19-4-2023 10:35 AM
End Date
19-4-2023 10:50 AM
Abstract
Lithium-ion batteries (LIBs) are instrumental to a renewable future, but environmentally friendly methods of recycling must be developed. Aluminum foil is used as the current collector, and it must be removed prior to hydrometallurgical recycling to ensure the recovery of valuable metals. Current methods use organic solvents to remove the organic binder, which serves as an adhesive link between the aluminum foil and cathode material; alkaline leaching of aluminum foil; and thermal separation. We used 2.5 M NaOH leaching to determine the mass percentage of aluminum present in 18650 battery cathodes and looked to replace NaOH with compounds of lower toxicity. Reagent solutions were poured to barely immerse the cathode samples, which were often folded to reduce volume. Our results found that the mass percentage of aluminum in the cathode strip was 2.55% and reactions only happen under high pH conditions (pH > 13). The reaction is indicated by the release of hydrogen gas, and the duration is upwards of 20 minutes. Future studies should focus on finding new reagents that would be lower in toxicity, price, and time to ensure the efficient removal of aluminum.
Removal of Aluminum Foil from Lithium-ion Battery Cathode in the Recycling Process
Lithium-ion batteries (LIBs) are instrumental to a renewable future, but environmentally friendly methods of recycling must be developed. Aluminum foil is used as the current collector, and it must be removed prior to hydrometallurgical recycling to ensure the recovery of valuable metals. Current methods use organic solvents to remove the organic binder, which serves as an adhesive link between the aluminum foil and cathode material; alkaline leaching of aluminum foil; and thermal separation. We used 2.5 M NaOH leaching to determine the mass percentage of aluminum present in 18650 battery cathodes and looked to replace NaOH with compounds of lower toxicity. Reagent solutions were poured to barely immerse the cathode samples, which were often folded to reduce volume. Our results found that the mass percentage of aluminum in the cathode strip was 2.55% and reactions only happen under high pH conditions (pH > 13). The reaction is indicated by the release of hydrogen gas, and the duration is upwards of 20 minutes. Future studies should focus on finding new reagents that would be lower in toxicity, price, and time to ensure the efficient removal of aluminum.