Energy-economy-environment assessment of key feedstock production for ternary lithium-ion batteries via hydrometallurgical recycling and natural exploitation

Abstract

The rapid increase in lithium-ion battery (LIB) production has intensified the demand for critical metals such as lithium, cobalt, and nickel, highlighting the urgent need for sustainable practices in LIB lifecycle management. Recycling LIBs is an effective measure generating feedstocks for refabrication in order to address resource strain, mitigate environmental impacts, aligning with the goals of cleaner production and sustainability. This study aims to provide a comprehensive energy-economy-environment assessment framework for feedstock production (Li2CO3, NiSO4·6H2O, CoSO4·7H2O) via hydrometallurgical recycling and natural exploitation. We compare recycling 1t of spent ternary LIBs to traditional natural exploitation methods by considering energy consumption, economic costs, and environmental impacts. Recycling routes incur 2.9-9.3×104 MJ energy consumptions, 3.8-4.4×104 CNY economic costs and 1.5-4.2×103 kg CO2 eq. emissions, while natural exploitation routes result in 4.6-8.6×104 MJ, 1.1-2.0×104 CNY and 2.7-3.9×103 kg CO2 eq, respectively. This study reveals that, in most environmental impact categories, natural exploitation routes fall between pyrolysis and non-pyrolysis recycling routes. Furthermore, significant difference in environmental and energy impacts per unit feedstock production are observed when utilizing mass-based and value-based allocation methods. When adopting mass-based, carbon emissions of Recycling route1 (based on full-component pyrolysis) is 41% of that using Li2CO3 from brine route for 1 kg of Li2CO3 production. This value increases to 112% when adopting value-based. Similarly, energy consumptions of Recycling route 1 are 65% and 175% of those using Li2CO3 from brine route, for mass-based and value-based methods, respectively. Our findings provide insights supporting sustainable battery recycling processes, which could further contribute to the broader field of cleaner production by promoting resource efficiency, reducing environmental impacts, and fostering sustainable industrial practices.