Highlights

• Korean researchers have developed an acid-free, closed-loop process that achieves over 80% lithium recovery and more than 99% lithium-carbonate purity.
• The solvent used in this process can be reused for 8 cycles, resulting in a 71% cost reduction.
• Fluorine impurity from LiPF₆ electrolyte and PVDF binder is critical, with 3.5 wt% F causing an 85% capacity loss while 0.1 wt% F provides performance similar to new commercial cathodes.
• This innovation indicates a potential rebalancing of battery-material refining in East Asia.
• However, real-world scaling challenges remain, especially regarding heterogeneous waste streams and industrial throughput.

---

Dr. Jong-Won Choi (opens in a new tab) and colleagues at the Korea Institute of Geoscience and Mineral Resources (opens in a new tab) (KIGAM), in collaboration with Jeonbuk National University and Huazhong University of Science and Technology, have developed an acid-free, closed-loop hydrometallurgical process that could redefine how the world recycles lithium-ion batteries.

Their paper, _“Closed-loop lithium recovery via antisolvent crystallization and the critical role of fluorine impurity control in regenerated NMC cathodes,”_now accepted in Separation and Purification Technology, reports> 80 % lithium recovery using simple water leaching, followed by > 99 % lithium-carbonate crystallization through an isopropanol-based antisolvent step. The recovered solvent is reused for eight consecutive cycles, cutting reagent cost by over 70 %.

Inside the Beaker—Methods in Motion

The process dissolves lithium ions from spent nickel-cobalt-manganese (NCM) cathodes while leaving transition metals intact. By introducing isopropanol (C₃H₈O) as an antisolvent, lithium carbonate precipitates selectively, allowing near-closed-loop recycling of both lithium and solvent. The team then re-fabricated NCM 622 cathodes from the recovered materials and systematically studied one overlooked impurity—fluorine (F)—originating from the electrolyte salt LiPF₆ and the polymer binder PVDF.

The F-Factor — When Trace Elements Turn Tragic

Performance tests revealed a sobering reality: fluorine contamination can make or break recycled-battery quality. Cathodes with 3.5 wt% % F lost 85 % of capacity, while those with only 0.1 wt% % F performed almost identically to new commercial NCM 622. In short, reclaiming lithium isn’t enough—purity engineering is mandatory. The work shows that even sustainable chemistry demands precision manufacturing discipline.

What It Means Beyond the Lab

For the broader rare-earth and critical-minerals ecosystem, this study underlines how Asia continues to dominate not only mining and refining but also process innovation. China controls roughly 90 % of global rare-earth and battery-material refining, yet this Korean-led advance hints at a regional rebalancing within East Asia itself. For Western supply-chain planners, it’s a reminder: without scalable, low-cost hydrometallurgy and impuritycontrol, “battery recycling” remains a slogan, not asector.

Caution Before Celebration

The paper’s limitations are pragmatic. Results were achieved at laboratory scale, using controlled waste streams. Real-world feedstocks—heterogeneous, contaminated, and carbon-rich—may challenge the process. Long-term solvent stability and industrial water management also need proof at ton-per-day throughput. Nevertheless, the economic modeling—71.6 % cost reduction—is compelling enough to justify pilot demonstrations.

A Quiet Revolution in a Beaker

Dr. Choi’s team did not invent alchemy, but something closer to industrial realism: a cleaner, closed-loop path to lithium recovery that could make future electric mobility both cheaper and greener. If scaled responsibly, it may narrowthe gap between policy ambition and chemical reality—and loosen,ever so slightly, the world’s dependence on Chinese refining lines.

Citation: Tran D. T., Vu T. T. P., Tran N. T. T., Ling L., Yoo B.-R., Lin X., Lee H., Choi J.-W., Ahn J., and Yun Y.-S.* (2025). Closed-loop lithium recovery via antisolvent crystallization and the critical role of fluorine impurity control in regenerated NMC cathodes. Separation and Purification Technology.

© 2025 Rare Earth Exchanges™ – Accelerating Transparency, Accuracy, and Insight Across the Rare Earth & Critical Minerals Supply Chain.