Smart sorting systems of spent lithium batteries: Challenges and pathways to industrial adoption

The rapid growth of lithium-ion batteries poses significant challenges for end-of-life (EoL) management, driven by diverse form factors, complex chemistries, and safety risks. Global EoL volumes are projected to exceed 1.2 million tonnes per year by 2030. Efficient, scalable sorting is therefore a critical bottleneck for a sustainable battery circular economy. This review synthesises academic and industrial evidence on battery sorting technologies using a system-level framework that integrates technical performance, economic scalability, safety, regulatory compliance, and traceability. Sorting technologies should not be treated as competing one-size-fits-all solutions. Instead, the sector is stratifying into operator segments with distinct optimisation priorities. Large-scale recyclers (LsR) favour high-throughput sensing to protect material purity and compliance. Small and medium-sized enterprises adopt cost-effective vision-based systems to balance automation and capital constraints. EV-focused operations deploy diagnostic-driven and robotic platforms to prioritise safety and residual value. This segmentation reflects durable economic and regulatory asymmetries rather than temporary technical limits. Key gaps remain in traceability integration and standardisation. A policy-aligned roadmap is proposed to support implementation of Regulation (EU) 2023/1542. • System-level framework linking sorting technologies to performance, safety, traceability, and regulatory compliance in EoL Li-ion chains. • Recycling sector is structurally segmented into large-scale recyclers, SMEs, and EV-focused operators. • Smart sorting systems achieve >90% accuracy vs 60-80% for manual methods.