Direct Recycling of Nickel-manganese-cobalt Cathode Materials from Lithium Batteries Using an All-in-one Rotary Kiln Reactor

The Department of Energy (DoE) has identified the important need to recycle, recover, and reuse the critical materials involved in lithium battery (LiB) technology. It is reported that in 2018 the world consumed over 50,000 tons of various lithium and transition metal salts to meet the production of LiBs needed for the worldwide energy storage needs. The market forecast for LiBs suggest that the demand for these metal salts will increase significantly due to proliferation of electric vehicles requiring increased mining and metallurgical processes to source these materials. A sustainable alternative toincreased mining for these metals is to recycle the end of life LiBs. Conventional hydrometallurgical and pyrometallurgical processing has been demonstrated for the LiB recycling. These methods, however, involve several energy intensive processing steps including complex chemical reactions and purification steps for leaching and separating metals components individually, which also produces significant amounts of chemical waste. To address this opportunity, Hazen Research in partnership with Argonne National Laboratory (ANL) proposes to develop and demonstrate the technical feasibility for the direct recyclingofNMC-622 cathode materials from the end-of-life lithium batteries (LiBs) using an all-in-one rotary kiln (RK)reactor. Our RK reactor is designed to treat the black mass (NMC-622 + PVDF binder + conductive carbon) in sequential steps of binder and carbon burn-out, re-lithiation, and re-crystallization to restore the NMC-622 cathode powders to their original composition, structure, and properties. Our proposal forusing an all-in-one RK reactor is a new direction towards a low-cost, energy efficient, and chemical waste-free method for the direct recycling of LIB cathodes. If successful, our proposal will facilitate the growth of a globally competitive direct recycling industry in the US, thereby reducing our reliance on foreign sources for materials and reducing the cost of LiBs. During this Phase-I effort, the Hazen Research-ANL team will perform the following tasks: design, fabricate, and test the proposed RK reactor with an attached ultrasonic nebulizer for an in-situ re-lithiation step and with auxiliary attachments for the burn-out and recrystallization, conduct process development for sequential burn-out (to remove more than 99.75% of the total carbon), re-lithiation (to the original stoichiometry) and re-crystallization (to the layeredstructure) using the RK reactor, demonstrate direct recycling technologies to reproduce NMC-622 cathode powders with similar electrochemical performance as the pristine sample. The global LiB market reached $28.5 Bn in 2018 and is projected to grow at an 11% compound annual growth rate through 2024. Large amounts of LiBs are expected to reach their end-of-life within the next decade. Some estimates suggest that more than one million tons of such LiBs is projected to enter the recycling market by 2025. The US currently recycles less than 5% of LiBs. Since more than 30% of the LiB cost account for cathode materials and their processing, its recovery, reprocessing, and reuse can significantly reduce the production cost of LiBs. We are targeting direct recycling methods at reduced energy consumption and yielding reusable battery-grade cathode materials. The technology is expected to contribute to the DOE’s goal of accelerating the growth of a profitable LiB recycling market. Of particular interest is use of directly recycled cathode powders in electric vehicles. The main benefit of our proposal is to help grow a globally competitive direct recycling industry in theUS that will reduce our reliance on foreign sources for materials and decrease the cost of LiBs. Accelerating and advancing direct recycling of LiBs will help meet the DoE-Vehicle Technology Office goal of less than $100/kWh through the increased use of domestically recycled sources of battery materials.