Circular production of cathode active materials from spent batteries via large-scale CO2-and NH3-assisted waste-to-resource integration

Abstract

The rising demand for lithium-ion batteries (LIBs) has raised concerns about lithium resource depletion and environmental impacts. While conventional recycling focuses on lithium recovery, this study presents a more sustainable pathway by producing sodium carbonate, a key reagent in lithium recovery, through industrial byproduct utilization. An integrated system combining an integrated gasification combined cycle (IGCC), ammonia recovery, the Solvay process, and hydrometallurgy is proposed. CO2 captured from IGCC and NH3 recovered from biogas digestate are used to synthesize sodium carbonate, which is then applied in the hydrometallurgical recovery of cathode active materials (CAMs) from spent LIBs. A case study based on a South Korean IGCC facility demonstrates both economic and environmental benefits. The estimated CAM production cost lies (23 US$/kg CAM) within the typical literature range (19 to 30 US$/kg CAM), while greenhouse gas emissions are reduced by 33% compared to virgin CAM production. Additionally, surplus electricity from a nearby solar farm can supply up to 47% of the process's electricity demand, contributing to a cleaner energy mix. This study highlights the potential of integrating waste recovery with LIB recycling to promote circularity and reduce environmental burdens. The proposed system offers a scalable and eco-efficient solution for sustainable battery material production.