Method of separation of active material from current collectors using ultrasonication

Abstract

The growing demand for batteries has strained the supply chain and emphasised the need for effective recycling methods. This thesis explores the use of ultrasonication as an efficient preprocessing technique for material removal in lithium-ion battery recycling. Ultrasonication utilises sound waves to create microbubbles that induce cavitation near the electrode surface, resulting in shear forces that aid in material removal. The study investigates various parameters to optimise the efficiency of ultrasonication, utilising laboratory-made electrodes. These electrodes are carefully produced through a meticulous process involving slurry mixing, spreading, drying, and calendaring. The optimised parameters for ultrasonication are determined through systematic variations of frequency, power, water level, temperature, and time. The effects on the electrode sheet are analysed to evaluate the outcome. By thoroughly examining the results of 32 iterations based on parameter variations, the study compiles the optimised parameters to minimise damage to the current collectors while maximising material removal efficiency. Additionally, the thesis addresses the industrial adaptability of ultrasonication for battery recycling, discussing two different approaches and considering challenges and scalability issues. Through these discussions, the study offers insights into the feasibility of implementing ultrasonication in large-scale recycling facilities, highlighting potential concerns and areas that require further development. Moreover, the method demonstrates its capability to produce higher-purity materials compared to conventional shredding processes, thereby increasing the value of the recovered materials.