Technologies for recycling and disposal of lithium power sources

Researchers at the Institute of Transport Systems and Technologies of the National Academy of Sciences of Ukraine are actively conducting scientific studies to improve methods and technologies for processing lithium power sources. In particular, they have proposed a preliminary battery recycling technology based on acoustic (ultrasound) and/or hydrodynamic cavitation methods, which enables the separation of active materials from current collectors. Further processing of the liquid mixture containing active materials is carried out using active magnetic separation with supermagnets arranged in a Halbach array, allowing the separation of metal fractions containing lithium, cobalt, nickel, manganese, and iron from non-metallic compounds. This preliminary processing of spent lithium batteries increases the efficiency of technological processes and recovers valuable metal materials with minimal energy consumption and environmental risks.

Scheme of preliminary processing and magnetic separation
of lithium batteries

Based on the research conducted to enhance lithium power source recycling methods, new preliminary processing and magnetic separation technologies have been proposed, with their general scheme illustrated in the figure.

The key idea is that the preliminary processing of lithium batteries is performed by exposing their electrodes to ultrasound or hydrodynamic cavitation. As a result, the active materials separate from the current collectors and, in the form of a liquid mixture, undergo magnetic separation using powerful supermagnets arranged in a Halbach array. The figure highlights the main processing operations:

• Ultrasound cavitation of the liquid (electrolyte) is carried out in an ultrasonic reactor where lithium batteries (denoted as Ak) are placed.
• Alternatively, hydrodynamic cavitation of the liquid is performed using Venturi tubes directed into battery cells (Ak-battery).
• A magnetic separator extracts materials containing cobalt, nickel, manganese, iron, and lithium (Me) from non-metallic substances.

Since lithium is found in compounds with ferromagnetic metals, it is also captured within the Me fraction. The use of powerful NdFeB supermagnets (with polarity indicated by arrows), arranged in a Halbach array, significantly enhances the efficiency of magnetic separation. The width of the material stream subjected to magnetic separation should not exceed 2-3 times the average size of the supermagnets, as this determines the region of maximum magnetic field intensity.

This preliminary recycling process for spent lithium batteries improves technological efficiency while recovering valuable metal materials with minimal energy costs and environmental impact.