Himanshu Gupta, N. Raveendran Shiju
The rapid expansion of lithium-ion battery (LIB) applications over the past decade—driven by the rise in portable electronics and electric vehicles—has led to a significant increase in battery waste. While the recovery of valuable metals such as lithium and cobalt from spent LIBs has received considerable attention, the recycling of separator materials remains largely neglected. These separators, typically made from polyethylene (PE) and polypropylene (PP), are critical to battery function yet are often discarded through landfilling, raising environmental concerns due to their non-biodegradable nature. This mini-review highlights the emerging need to address the end-of-life management of LIB separators, discusses recent advances in their reuse and recycling, and outlines potential pathways to incorporate these materials into circular economy models. Greater focus on separator recovery could enhance the overall sustainability and resource efficiency of LIB recycling processes.