Life cycle assessment of recycling lithium-ion battery related mineral processing by-products: A review

The increasing demand for lithium-ion batteries (LIBs) has accelerated the extraction and processing of numerous critical minerals embedding lithium, cobalt, manganese, nickel, and graphite. Extracting these elements from the earth's crust is inevitably associated with the generation of by-products, leading to various environmental impacts that need to be carefully considered. It is essential to integrate these by-products into sustainable value chains and demonstrate their environmental benefits. Life cycle assessment (LCA) provides a systematic approach for analysing the integration of by-products in a circular economy and assessing their environmental impact throughout the product's life cycle. Although LCA enables decision-makers to evaluate the potential benefits and trade-offs associated with using by-products in the circular economy, its acceptance by the mining and processing community is limited. This literature survey shows that increasing attention is being directed towards LCA-based research in order to foster the circular economy of mineral processing by-products related to LIBs. While more authoritative and effective information channels are opening up for researchers and end-users to learn about LCA in this context, two main issues are present in current research, namely the lack of equilibrium (i.e. focus on small and isolated areas that may not represent the whole market) and the lack of systematic criteria of assessment (i.e. environmental impacts are difficult to compare). Through the analysis of 79 relevant LCA papers, we realized that the current research on mineral processing by-product recycling is limited to specific areas, such as by-product selection, recycling method qualification, and assessment of environmental impact categories. These areas are often studied in isolation, leading to a fragmented understanding of the broader environmental impacts of recycling by-products in the context of lithium-ion battery production. Furthermore, comparing LCA results across different studies on the same research topic can be challenging. To improve future LCA research on mineral processing by-product recycling, greater attention should be paid to non-hotspot fields, and systematic criteria of sustainability evaluation specifically cast for critical minerals should be established to improve decision-making.