Optimisation of a Li-ion batteries recycling process: Electrodes Separation

Abstract

Li-ion (LIB) batteries are a type of battery widely used in electric vehicles due to their specific characteristics. Their manufacture requires the use of critical raw materials such as cobalt, lithium, and nickel. Thus, the need to integrate the recycling of batteries at the end of their life is essential not only from an environmental point of view but also for the economic importance of these elements. The objective of the work is the study of anode and cathode separation technologies in a Li-ion battery in the upstream part of the process, by physical separation technologies, before entering the heat treatment. Two main technologies of mechanical separation were studied in this thesis including: A dry separation route by a pneumatic classifier with a vertical gas flow of the ZigZag type. The density separation tests handled in a lab and pilot scale proved that 34% of the total stream mass could be discarded in losing only 8% of the cathode. Electrostatic separation is another potential technique that uses the conductivity properties of the battery components to achieve a good separation between anode and cathode, by concentrating anodes in the conductive bin. It allows to recover up to 75% of copper in the conductive fraction for a total yield of 36% and an anode grade of 17% with only 4% cathode loss.