Recycling of Waste Secondary Battery Materials to Recovery of Lithium Carbonate By Using Eco-Friendly Pyro-Metallurgical Electrolysis Process

Abstract

Recently, many types of vehicles that has been used fossil fuels energy are being replaced with EVs (Electric Vehicles) uses electrical energy. Since secondary batteries that use as the main power device of electric vehicles have a constant lifespan of 7 to 8 years, accordingly, many operating countries are constructing various plans and policies to handle with this issue. Various valuable rare metals such as nickel, cobalt, lithium, and manganese that all has limited resource, are contained in the wasted cathode material, and it could be used as a useful high-quality source if those materials can be recovered in recycle process. Thus, in this study, recover existing resources from waste cathode materials through the eco-friendly Molten Carbonate Electrolysis (MCE) process was performed. Through the process, the lithium, the main recovery target element could be recovered in the form of a compound as lithium carbonate while valuable metals such as nickel and manganese were separated and precipitated. Even though this process does not require any of acidic or organic solvent, it showed high recovery results with more environmentally friendly than the commercial hydrometallurgical recovery method while the sequence was also relatively simple. Various analysis was performed in Xray diffraction, X-ray fluorescence and FE-SEM to confirming characteristics status in recovered lithium carbonate and other precipitated powder, and thermodynamical calculation was accompanied by HSC chemistry to estimate the proper process conditions and electrode materials. In addition, through electrochemical analysis such as chronoamperometry (CA) and cyclic-voltammetry (CV), the correlation between electrode reaction tendency and lithium compound recovery rate was identified.