Deep eutectic solvents in battery recycling: A sustainable path forward

The recycling of various energy storage materials, including but not limited to lithium-based batteries, has become increasingly important due to the rapid growth of the battery sector and its potential to strain global material supply chains. Recycling not only helps recover valuable metals and minerals but also reduces reliance on environmentally harmful mining practices and creates local economic opportunities. However, current recycling methods often involve chemical processes that are not entirely environmentally friendly. As a greener alternative, deep eutectic solvents (DESs) are drawing attention for their potential in battery recycling technologies. This review explores the progress on DESs in this field. It also examines the recycling of polymer components, often overlooked but crucial for a complete recycling strategy. Furthermore, a brief life-cycle-assessment (LCA) is included to evaluate the environmental benefits and limitations of DES-based recycling. Early integration of LCA can guide sustainable process development, identify environmental trade-offs, and support sound decision-making, aligning emerging recycling technologies with sustainability targets and regulatory frameworks. While energy storage represents the bottleneck to a successful energy transition, the recycling of materials used in storage devices constitutes the foundation of a true circular economy, in which DES systems possess the potential to play a pivotal role.