This thesis discusses the basics of operation of lithium-ion technologies used in electric vehicles. Due to increasing demands for transition to greener technologies, the number of electric vehicles is expected to rise in the future, and as a result the amount of battery waste will also increase.
After ceasing the operation of cells in the form of a vehicle battery, they can be used to store surplus electricity from the grid, thus prolonging their life expectancy and using them more effectively. Each product once ends up in the form of waste that needs to be handled properly so that its harmful effects are diminished as much as possible. At the same time, after recycling, they can also present a source of valuable raw materials. This thesis also includes the current legal framework in the field of collection and recycling of waste batteries in Europe and Slovenia with forecasts of changes in future periods.
Li-Ion batteries and their components can pose certain dangers in different stages of their life cycle. In extreme cases, overheating, appearance of sparks, flames and even explosions can occur, but with proper handling and inclusion of multiple safety measures that probability is extremely low.
Disassembly of battery cells is one of the initial steps of recycling. It presents a certain deviation from proper handling since it includes taking the battery apart. Therefore, recycling should be done by a professional who takes additional safety measures and is qualified for such work. The recycling process also includes the collection of waste lithium-ion batteries, which is followed by sorting and mechanical separation of the components. Recycling is concluded by using various pyrometallurgical and hydrometallurgical processes to separate and extract critical metals, which are an integral part of modern-technology batteries.
The experimental part of this thesis was performed on a Li-Ion battery with a NMC cathode. To choose the recycling process properly, it is crucial to know the exact composition of the examined battery, therefore I performed various analyses of the components. Using SEM-EDS analysis, I determined the basic materials present in anode and cathode powder. Since the emphasis is mainly on effectively recycling the cathode materials, I confirmed the composition of the active cathode material with FAAS and conducted a TGA-MS analysis. In the final stage I also performed an extraction of cathode powder elements Li, Ni, Mn, and Co by employing various hydrometallurgical processes.
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