The widespread consumption of electronic devices has made spent batteries an ongoing economic and ecological concern with a compound annual growth rate of up to 8% during 2018, and expected to reach betwe. The growth of e-waste streams brought by accelerated consumption trends and shortened. 2.1. Metal nanostructuresOver the past decade, primary and secondary batteries have migrated from bulk materials into nanostructures derived from transition m. 3.1. Risk assessment of battery nanomaterialsGiven the emerging nature of nanomaterials applied for battery enhancement, th. The regulatory action of the USA, Germany, Japan and China on spent batteries is summarized by Fan et al. Most of these policies are constrained to the responsibility. This review briefly summarizes the main emerging materials reported to enhance battery performance and their potential environmental impact towards the onset of large-scale manu.