Recycling Valuable Metals from All Species of Spent Lithium-Ion Batteries using Non-Organic Solvents System

Lithium-ion batteries have become the mainstream energy storage material in various industries due to their high energy density, high operating voltage, wide temperature range, and long lifespan. In recent years, the electric vehicle industry has flourished in an effort to reduce environmental pollution. Lithium-ion batteries, with their aforementioned advantages, have replaced traditional nickel-hydrogen batteries as the dominant power source for electric vehicles. This surge in demand for lithium-ion batteries is expected to generate a significant amount of waste batteries. Improper handling of these discarded batteries can pose serious risks to the environment and human health. Moreover, lithium batteries contain valuable metals such as lithium, cobalt, nickel, and manganese, which are vital and strategic resources. Developing suitable technologies to recycle and reuse these waste lithium-ion batteries can not only reduce environmental pollution but also enhance control over critical valuable metal resources, particularly since these metals are not domestically available and currently rely on imports. Mastering recycling techniques offers the opportunity to treat a large quantity of waste batteries as a valuable mineral deposit through urban mining. Therefore, lithium-ion battery recycling is poised to become a highly promising and profitable industry.<br/>With the objectives of low cost, continuous operation, and scalability, we have developed an efficient, non-organic solvent recycling process for all species of lithium-ion batteries. Initially, we simulated the recycling scenario using simulated materials. The target elements including iron, phosphorus, and lithium, can be easily separated using pH control and therefore precipitants. However, the separation of nickel, cobalt, and manganese, which are closely positioned in the periodic table with similar physical and chemical properties, presents challenges in non-organic solvents system. To overcome this, we identified two aqueous phase precipitants, KMnO₄ and NaClO, combining with pH control, successfully separate these three elements without mutual interference. Ultimately, this method achieves high purity of recovered materials of all elements, with individual product purities reaching 98.72 wt% for iron phosphate, 92.97 wt% for manganese oxide, 98.06 wt% for cobalt oxide, 95.86 wt% for nickel hydroxide, and 96.76 wt% for lithium carbonate. This proposed process also provides high recovery yields which recovery yield reaching above 99% for valuable elements. To ensure the applicability of this technique to the industry, the real industrial black powder from a battery recycling plant was also applied for this research. Under the same process, we collected all the recycling products of above 90 wt% purity and the recovery yields reaching above 96% for valuable elements. Compared to existing lithium battery recycling technologies, this process offers a broader range of target products and provides an efficient recycling process with mass production potential.