Spent lithium-ion batteries (LIBs) pose various environmental risks due to hazardous materials like heavy metals and toxic gases. Improper disposal or recycling can lead to soil, water, and air contamination through leaching, fire, and explosions, posing a threat to both ecosystems and human health. The review highlights the need for improved recycling infrastructure, stricter regulations, and further research to address these challenges.

The authors disclose funding from the Faraday Institution (ReLIB and SafeBatt projects) and EPSRC. While not necessarily a direct conflict, this funding source has a clear interest in promoting battery research and development, which might subtly influence the framing of the challenges associated with battery waste.

This review provides a comprehensive and up-to-date overview of the environmental impacts of spent LIBs. It effectively categorizes sources, pathways, and hazards, drawing attention to important issues. The lack of primary research and limited guidance for future studies hold it back from a top rating. The disclosed funding sources, while not directly conflicting, could represent a subtle bias.