Towards a sustainable approach using mineral or carboxylic acid to recover lithium from lithium iron phosphate batteries

Abstract

Lithium‑iron phosphate (LFP) batteries are commonly used in electric vehicles and stationary energy storage systems due to their high energy density, long cycle life, and safety. Processing of LiFePO4 batteries is difficult due to the complex battery chemistry and the lack of effective recycling options. The information currently available on recycling LFP batteries points to a low recycling efficiency and material recovery rate, which causes significant losses of valuable metals and environmental discharges of hazardous materials. Given the rising need for batteries and the detrimental environmental impact of their disposal, this is a critical concern. Therefore, it is essential to create effective and sustainable battery recycling methods in order to reduce waste and lower the impact on the environment. The goal of this publication is to outline a viable alternate strategy for recycling LFP batteries. Lowest acid concentrations are utilized in this method in order to enable the selective leaching of lithium. Both inorganic acids (e.g., H3PO4 and H2SO4) and organic alternatives (such as citric acid and oxalic acid) are tested at low concentrations (0.01–0.1 mol/l), in order to integrate sustainability aspects at this early stage of development and to directly compare the outcomes. Based on thermodynamic calculations, it was possible to recover lithium with a high efficiency (> 90%) using a subsequent precipitation sequence, thus returning this high-quality material to the raw material cycle with an appropriate morphology and purity.