Fundamental research on recycling spent lithium-ion batteries for environmental pollutant control

With the proposal of global carbon neutrality goals, lithium-ion batteries (LIBs) are extensively employed in portable electronic devices and new energy electric vehicles due to their unique advantages. However, their limited service life inevitably leads to the generation of a substantial amount of spent lithium-ion batteries (SLIBs) after decommissioning. If not handled appropriately, those SLIBs can severely harm the environment owing to their leachable potentially toxic metals (PTMs) and toxic electrolytes. SLIBs contains abundant metals (e.g., Fe, Co, Ni, Mn), which can be recovered through appropriate methods to synthesize functional catalysts. Repurposing SLIBs as functional catalysts to remove harmful pollutants represents a win-win strategy that not only mitigates the environmental challenges posed by SLIBs but also addresses the removal of pollutants. Environmental pollutants (e.g., organic pollutants, PTMs, and gas-phase pollutants) pose severe threats to both ecosystems and human health. Developing effective technologies for their removal has emerged as a critical priority. This review primarily discusses the latest research on recycling methods for SLIBs and their repurposing as functional catalysts for applications in organic pollutants removal, PTMs elimination, gas-phase pollutants degradation, and salt ions removal. Furthermore, the current challenges and future research directions of recycling SLIBs for environmental contaminant control applications are also proposed.