Efficient lithium recovery from industrial lithium iron phosphate (LFP) blackmass using formic acid-enabled hydrometallurgy
Ayesha Tasawar, Daniel Dotto München, Alexander Birich, Rungsima Yeetsorn, Walter Sebastian Scheld, Waritnan Wanchan, Benjamin Butz, Bernd Friedrich
Abstract
As millions of LFP batteries reach their end of life, the challenge of selectively extracting lithium from industrial blackmass, loaded with impurities, has become a focal point for sustainable innovation in battery recycling. However, industrial-scale LFP recycling remains technically challenging due to the complex composition of real battery waste, including high graphite content, binders, and metallic inclusions that undermine conventional leaching processes. In this research study, a selective, green hydrometallurgical approach tailored for impurity-rich LFP blackmass is presented. Using only trace (“hint of acid”) amounts of formic acid with hydrogen peroxide and two-step leaching, achieving ∼94.5% lithium extraction in the two-step formic acid route, whereas the trace sulfuric acid + H₂O₂ condition delivers the highest selectivity, reaching >95% lithium recovery with negligible iron co-leaching, and producing lithium carbonate as an end product (confirmed by XRD and SEM) without the environmental burden of aggressive reagents or high-temperature treatment. Key to this process is careful control of solution pH and oxidation conditions, allowing a scalable, cost‑effective route to close the loop on LFP materials, and proving that the high‑yield lithium recovery and environmental responsibility can be achieved in the same process.