Magnetic Separation Techniques in Recycling of Lithium-Ion Batteries

摘要

The need to decarbonise personal transportation has lead to a growth in the number of electric vehicles being used around the world, with the global EV fleet exceeding 5.1 million in 2018. Lithium-ion batteries from an end of life EV pack may serve well in second life applications such as stationary storage, others are more suited for recycling. LIB recycling facilities in the UK are limited to collection and comminution. The ReLiB project is attempting to address this. In order for recycling of lithium-ion cells to be cost-effective, physical processing techniques are necessary to separate the active material from the current collectors, casings and plastics. Improvements in physical processing techniques can help reduce hydrometallurgical processing costs, or assist in the direct recycling of lithium-ion battery cathode materials, without having to resort to hydrometallurgical processing. In this work, lithium ion pouch cells have been stabilised, shredded, and dried to remove solvents. This dry material was then separated into plastics, cathode, and an anode and casing stream. Electrostatic separation was used to remove the separator. A rare earth roll magnetic separator was used to recover shredded cathode material from the mixed anode, cathode and casings stream. These anode and cathode streams were treated separately to remove the active material from the foil. The recovered fine powders were put through a wet high intensity magnetic separation to further improve the purity of the materials, which were then characterised. We discuss the yields and purity of the waste streams separated through the high intensity magnetic separation process.